release 0.9.4

- delete oauth clients for servers when they shutdown
- avoid deleting oauth clients for servers still running across an 0.8 -> 0.9 upgrade, when the oauth client ids changed from `user-NAME` to `jupyterhub-user-NAME`

.circleci/config.yml

@@ -0,0 +1,21 @@
+# Python CircleCI 2.0 configuration file
+# Updating CircleCI configuration from v1 to v2
+# Check https://circleci.com/docs/2.0/language-python/ for more details
+#
+version: 2
+jobs:
+  build:
+    machine: true
+    steps:
+      - checkout
+      - run:
+          name: build images
+          command: |
+            docker build -t jupyterhub/jupyterhub .
+            docker build -t jupyterhub/jupyterhub-onbuild onbuild
+            docker build -t jupyterhub/jupyterhub:alpine -f dockerfiles/Dockerfile.alpine .
+            docker build -t jupyterhub/singleuser singleuser
+      - run:
+          name: smoke test jupyterhub
+          command: |
+            docker run --rm -it jupyterhub/jupyterhub jupyterhub --help

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,37 @@
+---
+name: Bug report
+about: Create a report to help us improve
+
+---
+
+Hi! Thanks for using JupyterHub.
+
+If you are reporting an issue with JupyterHub, please use the [GitHub issue](https://github.com/jupyterhub/jupyterhub/issues) search feature to check if your issue has been asked already. If it has, please add your comments to the existing issue.
+
+**Describe the bug**
+A clear and concise description of what the bug is.
+
+**To Reproduce**
+Steps to reproduce the behavior:
+1. Go to '...'
+2. Click on '....'
+3. Scroll down to '....'
+4. See error
+
+**Expected behavior**
+A clear and concise description of what you expected to happen.
+
+**Screenshots**
+If applicable, add screenshots to help explain your problem.
+
+**Desktop (please complete the following information):**
+ - OS: [e.g. iOS]
+ - Browser [e.g. chrome, safari]
+ - Version [e.g. 22]
+
+**Additional context**
+Add any other context about the problem here.
+
+- Running `jupyter troubleshoot` from the command line, if possible, and posting
+its output would also be helpful.
+- Running in `--debug` mode can also be helpful for troubleshooting.

.github/ISSUE_TEMPLATE/installation-and-configuration-issues.md

@@ -0,0 +1,7 @@
+---
+name: Installation and configuration issues
+about: Installation and configuration assistance
+
+---
+
+If you are having issues with installation or configuration, you may ask for help on the JupyterHub gitter channel or file an issue here.

.github/issue_template.md

@@ -1,29 +0,0 @@
-Hi! Thanks for using JupyterHub.
-
-If you are reporting an issue with JupyterHub:
-
-- Please use the [GitHub issue](https://github.com/jupyterhub/jupyterhub/issues)
-  search feature to check if your issue has been asked already. If it has,
-  please add your comments to the existing issue.
-
-- Where applicable, please fill out the details below to help us troubleshoot
-  the issue that you are facing. Please be as thorough as you are able to
-  provide details on the issue.
-
-**How to reproduce the issue**
-
-**What you expected to happen**
-
-**What actually happens**
-
-**Share what version of JupyterHub you are using**
-
-Running `jupyter troubleshoot` from the command line, if possible, and posting
-its output would also be helpful.
-
-```
-
-Insert jupyter troubleshoot output here
-
-
-```

.gitignore

@@ -14,11 +14,13 @@ docs/source/_static/rest-api
 /jupyterhub_config.py
 jupyterhub_cookie_secret
 jupyterhub.sqlite
-share/jupyter/hub/static/components
+package-lock.json
-share/jupyter/hub/static/css/style.min.css
+share/jupyterhub/static/components
-share/jupyter/hub/static/css/style.min.css.map
+share/jupyterhub/static/css/style.min.css
+share/jupyterhub/static/css/style.min.css.map
 *.egg-info
 MANIFEST
 .coverage
 htmlcov
-
+.idea/
+.pytest_cache

.travis.yml

@@ -3,13 +3,14 @@ sudo: false
 cache:
   - pip
 python:
-  - nightly
   - 3.6
   - 3.5
-  - 3.4
+  - nightly
 env:
   global:
     - ASYNC_TEST_TIMEOUT=15
+    - MYSQL_HOST=127.0.0.1
+    - MYSQL_TCP_PORT=13306
 services:
   - postgres
   - docker
@@ -20,6 +21,7 @@ before_install:
   - npm install
   - npm install -g configurable-http-proxy
   - |
+    # setup database
     if [[ $JUPYTERHUB_TEST_DB_URL == mysql* ]]; then
       unset MYSQL_UNIX_PORT
       DB=mysql bash ci/docker-db.sh
@@ -27,30 +29,25 @@ before_install:
       pip install 'mysql-connector<2.2'
     elif [[ $JUPYTERHUB_TEST_DB_URL == postgresql* ]]; then
       DB=postgres bash ci/init-db.sh
-      pip install psycopg2
+      pip install psycopg2-binary
     fi
 install:
-  - pip install -U pip
+  - pip install --upgrade pip
   - pip install --pre -r dev-requirements.txt .
   - pip freeze
 
 # running tests
 script:
   - |
-    if [[ ! -z "$JUPYTERHUB_TEST_DB_URL" ]]; then
+    # run tests
-      # if testing upgrade-db, run `jupyterhub token` with 0.7
+    set -e
-      # to initialize an old db. Used in upgrade-tests
+    pytest -v --maxfail=2 --cov=jupyterhub jupyterhub/tests
-      export JUPYTERHUB_TEST_UPGRADE_DB_URL=${JUPYTERHUB_TEST_DB_URL}_upgrade
+  - |
-      # use virtualenv instead of venv because venv doesn't work here
+    # build docs
-      python -m pip install virtualenv
+    pushd docs
-      python -m virtualenv old-hub-env
+    pip install -r requirements.txt
-      ./old-hub-env/bin/python -m pip install jupyterhub==0.7.2 psycopg2 'mysql-connector<2.2'
+    make html
-      ./old-hub-env/bin/jupyterhub token kaylee \
+    popd
-        --JupyterHub.db_url=$JUPYTERHUB_TEST_UPGRADE_DB_URL \
-        --Authenticator.whitelist="{'kaylee'}" \
-        --JupyterHub.authenticator_class=jupyterhub.auth.Authenticator
-    fi
-  - pytest -v --maxfail=2 --cov=jupyterhub jupyterhub/tests
 after_success:
   - codecov
 
@@ -61,11 +58,11 @@ matrix:
       env: JUPYTERHUB_TEST_SUBDOMAIN_HOST=http://localhost.jovyan.org:8000
     - python: 3.6
       env:
-        - MYSQL_HOST=127.0.0.1
-        - MYSQL_TCP_PORT=13306
         - JUPYTERHUB_TEST_DB_URL=mysql+mysqlconnector://root@127.0.0.1:$MYSQL_TCP_PORT/jupyterhub
     - python: 3.6
       env:
         - JUPYTERHUB_TEST_DB_URL=postgresql://postgres@127.0.0.1/jupyterhub
+    - python: 3.7
+      dist: xenial
   allow_failures:
     - python: nightly

CODE_OF_CONDUCT.md

@@ -0,0 +1 @@
+Please refer to [Project Jupyter's Code of Conduct](https://github.com/jupyter/governance/blob/master/conduct/code_of_conduct.md).

CONTRIBUTING.md

@@ -1,3 +1,98 @@
 # Contributing
 
 Welcome! As a [Jupyter](https://jupyter.org) project, we follow the [Jupyter contributor guide](https://jupyter.readthedocs.io/en/latest/contributor/content-contributor.html).
+
+
+## Set up your development system
+
+For a development install, clone the [repository](https://github.com/jupyterhub/jupyterhub)
+and then install from source:
+
+```bash
+git clone https://github.com/jupyterhub/jupyterhub
+cd jupyterhub
+npm install -g configurable-http-proxy
+pip3 install -r dev-requirements.txt -e .
+```
+
+### Troubleshooting a development install
+
+If the `pip3 install` command fails and complains about `lessc` being
+unavailable, you may need to explicitly install some additional JavaScript
+dependencies:
+
+    npm install
+
+This will fetch client-side JavaScript dependencies necessary to compile CSS.
+
+You may also need to manually update JavaScript and CSS after some development
+updates, with:
+
+```bash
+python3 setup.py js    # fetch updated client-side js
+python3 setup.py css   # recompile CSS from LESS sources
+```
+
+## Running the test suite
+
+We use [pytest](http://doc.pytest.org/en/latest/) for running tests. 
+
+1. Set up a development install as described above. 
+
+2. Set environment variable for `ASYNC_TEST_TIMEOUT` to 15 seconds:
+
+```bash
+export ASYNC_TEST_TIMEOUT=15
+```
+
+3. Run tests.
+
+To run all the tests:
+
+```bash
+pytest -v jupyterhub/tests
+```
+
+To run an individual test file (i.e. `test_api.py`):
+
+```bash
+pytest -v jupyterhub/tests/test_api.py
+```
+
+### Troubleshooting tests
+
+If you see test failures because of timeouts, you may wish to increase the
+`ASYNC_TEST_TIMEOUT` used by the
+[pytest-tornado-plugin](https://github.com/eugeniy/pytest-tornado/blob/c79f68de2222eb7cf84edcfe28650ebf309a4d0c/README.rst#markers)
+from the default of 5 seconds:
+
+```bash
+export ASYNC_TEST_TIMEOUT=15
+```
+
+If you see many test errors and failures, double check that you have installed
+`configurable-http-proxy`.
+
+## Building the Docs locally
+
+1. Install the development system as described above.
+
+2. Install the dependencies for documentation:
+
+```bash
+python3 -m pip install -r docs/requirements.txt
+```
+
+3. Build the docs:
+
+```bash
+cd docs
+make clean
+make html
+```
+
+4. View the docs:
+
+```bash
+open build/html/index.html
+```

Dockerfile

@@ -21,29 +21,25 @@
 # your jupyterhub_config.py will be added automatically
 # from your docker directory.
 
-FROM debian:jessie
+FROM ubuntu:18.04
-MAINTAINER Jupyter Project <jupyter@googlegroups.com>
+LABEL maintainer="Jupyter Project <jupyter@googlegroups.com>"
 
 # install nodejs, utf8 locale, set CDN because default httpredir is unreliable
 ENV DEBIAN_FRONTEND noninteractive
-RUN REPO=http://cdn-fastly.deb.debian.org && \
+RUN apt-get -y update && \
-    echo "deb $REPO/debian jessie main\ndeb $REPO/debian-security jessie/updates main" > /etc/apt/sources.list && \
-    apt-get -y update && \
     apt-get -y upgrade && \
-    apt-get -y install wget locales git bzip2 &&\
+    apt-get -y install wget git bzip2 && \
-    /usr/sbin/update-locale LANG=C.UTF-8 && \
+    apt-get purge && \
-    locale-gen C.UTF-8 && \
-    apt-get remove -y locales && \
     apt-get clean && \
     rm -rf /var/lib/apt/lists/*
 ENV LANG C.UTF-8
 
 # install Python + NodeJS with conda
-RUN wget -q https://repo.continuum.io/miniconda/Miniconda3-4.2.12-Linux-x86_64.sh -O /tmp/miniconda.sh  && \
+RUN wget -q https://repo.continuum.io/miniconda/Miniconda3-4.5.1-Linux-x86_64.sh -O /tmp/miniconda.sh  && \
-    echo 'd0c7c71cc5659e54ab51f2005a8d96f3 */tmp/miniconda.sh' | md5sum -c - && \
+    echo '0c28787e3126238df24c5d4858bd0744 */tmp/miniconda.sh' | md5sum -c - && \
     bash /tmp/miniconda.sh -f -b -p /opt/conda && \
     /opt/conda/bin/conda install --yes -c conda-forge \
-      python=3.5 sqlalchemy tornado jinja2 traitlets requests pip pycurl \
+      python=3.6 sqlalchemy tornado jinja2 traitlets requests pip pycurl \
       nodejs configurable-http-proxy && \
     /opt/conda/bin/pip install --upgrade pip && \
     rm /tmp/miniconda.sh
@@ -52,8 +48,7 @@ ENV PATH=/opt/conda/bin:$PATH
 ADD . /src/jupyterhub
 WORKDIR /src/jupyterhub
 
-RUN npm install --unsafe-perm && \
+RUN pip install . && \
-    pip install . && \
     rm -rf $PWD ~/.cache ~/.npm
 
 RUN mkdir -p /srv/jupyterhub/

MANIFEST.in

@@ -3,6 +3,7 @@ include COPYING.md
 include setupegg.py
 include bower-lite
 include package.json
+include package-lock.json
 include *requirements.txt
 include Dockerfile
 
@@ -18,15 +19,15 @@ graft docs
 prune docs/node_modules
 
 # prune some large unused files from components
-prune share/jupyter/hub/static/components/bootstrap/dist/css
+prune share/jupyterhub/static/components/bootstrap/dist/css
-exclude share/jupyter/hub/static/components/bootstrap/dist/fonts/*.svg
+exclude share/jupyterhub/static/components/bootstrap/dist/fonts/*.svg
-prune share/jupyter/hub/static/components/font-awesome/css
+prune share/jupyterhub/static/components/font-awesome/css
-prune share/jupyter/hub/static/components/font-awesome/scss
+prune share/jupyterhub/static/components/font-awesome/scss
-exclude share/jupyter/hub/static/components/font-awesome/fonts/*.svg
+exclude share/jupyterhub/static/components/font-awesome/fonts/*.svg
-prune share/jupyter/hub/static/components/jquery/external
+prune share/jupyterhub/static/components/jquery/external
-prune share/jupyter/hub/static/components/jquery/src
+prune share/jupyterhub/static/components/jquery/src
-prune share/jupyter/hub/static/components/moment/lang
+prune share/jupyterhub/static/components/moment/lang
-prune share/jupyter/hub/static/components/moment/min
+prune share/jupyterhub/static/components/moment/min
 
 # Patterns to exclude from any directory
 global-exclude *~

PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1 @@
+

README.md

@@ -11,8 +11,8 @@
 
 
 [![PyPI](https://img.shields.io/pypi/v/jupyterhub.svg)](https://pypi.python.org/pypi/jupyterhub)
-[![Documentation Status](https://readthedocs.org/projects/jupyterhub/badge/?version=latest)](http://jupyterhub.readthedocs.org/en/latest/?badge=latest)
+[![Documentation Status](https://readthedocs.org/projects/jupyterhub/badge/?version=latest)](https://jupyterhub.readthedocs.org/en/latest/?badge=latest)
-[![Documentation Status](http://readthedocs.org/projects/jupyterhub/badge/?version=0.7.2)](http://jupyterhub.readthedocs.io/en/0.7.2/?badge=0.7.2)
+[![Documentation Status](http://readthedocs.org/projects/jupyterhub/badge/?version=0.7.2)](https://jupyterhub.readthedocs.io/en/0.7.2/?badge=0.7.2)
 [![Build Status](https://travis-ci.org/jupyterhub/jupyterhub.svg?branch=master)](https://travis-ci.org/jupyterhub/jupyterhub)
 [![Circle CI](https://circleci.com/gh/jupyterhub/jupyterhub.svg?style=shield&circle-token=b5b65862eb2617b9a8d39e79340b0a6b816da8cc)](https://circleci.com/gh/jupyterhub/jupyterhub)
 [![codecov.io](https://codecov.io/github/jupyterhub/jupyterhub/coverage.svg?branch=master)](https://codecov.io/github/jupyterhub/jupyterhub?branch=master)
@@ -20,7 +20,7 @@
 
 With [JupyterHub](https://jupyterhub.readthedocs.io) you can create a
 **multi-user Hub** which spawns, manages, and proxies multiple instances of the
-single-user [Jupyter notebook (IPython notebook)](https://jupyter-notebook.readthedocs.io)
+single-user [Jupyter notebook](https://jupyter-notebook.readthedocs.io)
 server.
 
 [Project Jupyter](https://jupyter.org) created JupyterHub to support many
@@ -34,11 +34,11 @@ Three main actors make up JupyterHub:
 
 - multi-user **Hub** (tornado process)
 - configurable http **proxy** (node-http-proxy)
-- multiple **single-user Jupyter notebook servers** (Python/IPython/tornado)
+- multiple **single-user Jupyter notebook servers** (Python/Jupyter/tornado)
 
 Basic principles for operation are:
 
-- Hub spawns a proxy.
+- Hub launches a proxy.
 - Proxy forwards all requests to Hub by default.
 - Hub handles login, and spawns single-user servers on demand.
 - Hub configures proxy to forward url prefixes to the single-user notebook
@@ -50,37 +50,62 @@ for administration of the Hub and its users.
 
 ## Installation
 
+
 ### Check prerequisites
 
-A Linux/Unix based system with the following:
+- A Linux/Unix based system
+- [Python](https://www.python.org/downloads/) 3.5 or greater
+- [nodejs/npm](https://www.npmjs.com/)
 
-- [Python](https://www.python.org/downloads/) 3.4 or greater
+  * If you are using **`conda`**, the nodejs and npm dependencies will be installed for
-- [nodejs/npm](https://www.npmjs.com/) Install a recent version of
+    you by conda.
-  [nodejs/npm](https://docs.npmjs.com/getting-started/installing-node)
-  For example, install it on Linux (Debian/Ubuntu) using:
 
-      sudo apt-get install npm nodejs-legacy
+  * If you are using **`pip`**, install a recent version of
+    [nodejs/npm](https://docs.npmjs.com/getting-started/installing-node).
+    For example, install it on Linux (Debian/Ubuntu) using:
 
-  The `nodejs-legacy` package installs the `node` executable and is currently
+    ```
-  required for npm to work on Debian/Ubuntu.
+    sudo apt-get install npm nodejs-legacy
+    ```
+
+    The `nodejs-legacy` package installs the `node` executable and is currently
+    required for npm to work on Debian/Ubuntu.
 
 - TLS certificate and key for HTTPS communication
 - Domain name
 
 ### Install packages
 
+#### Using `conda`
+
+To install JupyterHub along with its dependencies including nodejs/npm:
+
+```bash
+conda install -c conda-forge jupyterhub
+```
+
+If you plan to run notebook servers locally, install the Jupyter notebook
+or JupyterLab:
+
+```bash
+conda install notebook
+conda install jupyterlab
+```
+
+#### Using `pip`
+
 JupyterHub can be installed with `pip`, and the proxy with `npm`:
 
 ```bash
 npm install -g configurable-http-proxy
-pip3 install jupyterhub    
+python3 -m pip install jupyterhub    
 ```
 
 If you plan to run notebook servers locally, you will need to install the
 [Jupyter notebook](https://jupyter.readthedocs.io/en/latest/install.html)
 package:
 
-    pip3 install --upgrade notebook
+    python3 -m pip install --upgrade notebook
 
 ### Run the Hub server
 
@@ -99,7 +124,7 @@ more configuration of the system.
 
 ## Configuration
 
-The [Getting Started](http://jupyterhub.readthedocs.io/en/latest/getting-started/index.html) section of the
+The [Getting Started](https://jupyterhub.readthedocs.io/en/latest/getting-started/index.html) section of the
 documentation explains the common steps in setting up JupyterHub.
 
 The [**JupyterHub tutorial**](https://github.com/jupyterhub/jupyterhub-tutorial)
@@ -151,7 +176,7 @@ not, Jupyter Notebook version 4 or greater must be installed.
 
 The JupyterHub docker image can be started with the following command:
 
-    docker run -d --name jupyterhub jupyterhub/jupyterhub jupyterhub
+    docker run -p 8000:8000 -d --name jupyterhub jupyterhub/jupyterhub jupyterhub
 
 This command will create a container named `jupyterhub` that you can
 **stop and resume** with `docker stop/start`.
@@ -163,7 +188,7 @@ If you want to run docker on a computer that has a public IP then you should
 (as in MUST) **secure it with ssl** by adding ssl options to your docker
 configuration or by using a ssl enabled proxy.
 
-[Mounting volumes](https://docs.docker.com/engine/userguide/containers/dockervolumes/) will
+[Mounting volumes](https://docs.docker.com/engine/admin/volumes/volumes/) will
 allow you to **store data outside the docker image (host system) so it will be persistent**, even when you start
 a new image.
 
@@ -175,38 +200,9 @@ These accounts will be used for authentication in JupyterHub's default configura
 
 If you would like to contribute to the project, please read our
 [contributor documentation](http://jupyter.readthedocs.io/en/latest/contributor/content-contributor.html)
-and the [`CONTRIBUTING.md`](CONTRIBUTING.md).
+and the [`CONTRIBUTING.md`](CONTRIBUTING.md). The `CONTRIBUTING.md` file
-
+explains how to set up a development installation, how to run the test suite,
-For a **development install**, clone the [repository](https://github.com/jupyterhub/jupyterhub)
+and how to contribute to documentation.
-and then install from source:
-
-```bash
-git clone https://github.com/jupyterhub/jupyterhub
-cd jupyterhub
-pip3 install -r dev-requirements.txt -e .
-```
-
-If the `pip3 install` command fails and complains about `lessc` being
-unavailable, you may need to explicitly install some additional JavaScript
-dependencies:
-
-    npm install
-
-This will fetch client-side JavaScript dependencies necessary to compile CSS.
-
-You may also need to manually update JavaScript and CSS after some development
-updates, with:
-
-```bash
-python3 setup.py js    # fetch updated client-side js
-python3 setup.py css   # recompile CSS from LESS sources
-```
-
-We use [pytest](http://doc.pytest.org/en/latest/) for **running tests**:
-
-```bash
-pytest jupyterhub/tests
-```
 
 ### A note about platform support
 
@@ -237,7 +233,7 @@ our JupyterHub [Gitter](https://gitter.im/jupyterhub/jupyterhub) channel.
 
 - [Reporting Issues](https://github.com/jupyterhub/jupyterhub/issues)
 - [JupyterHub tutorial](https://github.com/jupyterhub/jupyterhub-tutorial)
-- [Documentation for JupyterHub](http://jupyterhub.readthedocs.io/en/latest/) | [PDF (latest)](https://media.readthedocs.org/pdf/jupyterhub/latest/jupyterhub.pdf) | [PDF (stable)](https://media.readthedocs.org/pdf/jupyterhub/stable/jupyterhub.pdf)
+- [Documentation for JupyterHub](https://jupyterhub.readthedocs.io/en/latest/) | [PDF (latest)](https://media.readthedocs.org/pdf/jupyterhub/latest/jupyterhub.pdf) | [PDF (stable)](https://media.readthedocs.org/pdf/jupyterhub/stable/jupyterhub.pdf)
 - [Documentation for JupyterHub's REST API](http://petstore.swagger.io/?url=https://raw.githubusercontent.com/jupyter/jupyterhub/master/docs/rest-api.yml#/default)
 - [Documentation for Project Jupyter](http://jupyter.readthedocs.io/en/latest/index.html) | [PDF](https://media.readthedocs.org/pdf/jupyter/latest/jupyter.pdf)
 - [Project Jupyter website](https://jupyter.org)

bower-lite

@@ -18,7 +18,7 @@ import shutil
 HERE = os.path.abspath(os.path.dirname(__file__))
 
 
-components = join(HERE, "share", "jupyter", "hub", "static", "components")
+components = join(HERE, "share", "jupyterhub", "static", "components")
 node_modules = join(HERE, "node_modules")
 
 if os.path.exists(components):

ci/docker-db.sh

@@ -8,7 +8,7 @@ export MYSQL_HOST=127.0.0.1
 export MYSQL_TCP_PORT=${MYSQL_TCP_PORT:-13306}
 export PGHOST=127.0.0.1
 NAME="hub-test-$DB"
-DOCKER_RUN="docker run --rm -d --name $NAME"
+DOCKER_RUN="docker run -d --name $NAME"
 
 docker rm -f "$NAME" 2>/dev/null || true
 

ci/init-db.sh

@@ -21,7 +21,7 @@ esac
 
 set -x
 
-$SQL 'DROP DATABASE jupyterhub;' 2>/dev/null || true
+for SUFFIX in '' _upgrade_072 _upgrade_081; do
-$SQL "CREATE DATABASE jupyterhub ${EXTRA_CREATE};"
+    $SQL "DROP DATABASE jupyterhub${SUFFIX};" 2>/dev/null || true
-$SQL 'DROP DATABASE jupyterhub_upgrade;' 2>/dev/null || true
+    $SQL "CREATE DATABASE jupyterhub${SUFFIX} ${EXTRA_CREATE};"
-$SQL "CREATE DATABASE jupyterhub_upgrade ${EXTRA_CREATE};"
+done

circle.yml

@@ -1,24 +0,0 @@
-machine:
-  services:
-    - docker
-
-dependencies:
-  override:
-    - ls
-
-test:
-  override:
-    - docker build -t jupyterhub/jupyterhub .
-    - docker build -t jupyterhub/jupyterhub-onbuild:${CIRCLE_TAG:-latest} onbuild
-
-deployment:
-  hub:
-    branch: master
-    commands:
-      - docker login -u $DOCKER_USER -p $DOCKER_PASS -e unused@example.com
-      - docker push jupyterhub/jupyterhub-onbuild
-  release:
-    tag: /.*/
-    commands:
-      - docker login -u $DOCKER_USER -p $DOCKER_PASS -e unused@example.com
-      - docker push jupyterhub/jupyterhub-onbuild:$CIRCLE_TAG

dev-requirements.txt

@@ -1,9 +1,14 @@
 -r requirements.txt
 mock
+beautifulsoup4
 codecov
 cryptography
 pytest-cov
 pytest-tornado
-pytest>=2.8
+pytest>=3.3
 notebook
 requests-mock
+virtualenv
+# temporary pin of attrs for jsonschema 0.3.0a1
+# seems to be a pip bug
+attrs>=17.4.0

dockerfiles/Dockerfile.alpine

@@ -0,0 +1,11 @@
+FROM python:3.6.3-alpine3.6
+
+ARG JUPYTERHUB_VERSION=0.8.1
+
+RUN pip3 install --no-cache jupyterhub==${JUPYTERHUB_VERSION}
+ENV LANG=en_US.UTF-8
+
+USER nobody
+CMD ["jupyterhub"]
+
+

dockerfiles/README.md

@@ -0,0 +1,21 @@
+## What is Dockerfile.alpine
+Dockerfile.alpine  contains base image for jupyterhub. It does not work independently, but only as part of a full jupyterhub cluster
+
+## How to use it?
+
+1. A running configurable-http-proxy, whose API is accessible. 
+2. A jupyterhub_config file.
+3. Authentication and other libraries required by the specific jupyterhub_config file.
+
+
+## Steps to test it outside a cluster
+
+* start configurable-http-proxy in another container
+* specify CONFIGPROXY_AUTH_TOKEN env in both containers
+* put both containers on the same network (e.g. docker create network jupyterhub; docker run ... --net jupyterhub)
+* tell jupyterhub where CHP is (e.g. c.ConfigurableHTTPProxy.api_url = 'http://chp:8001')
+* tell jupyterhub not to start the proxy itself (c.ConfigurableHTTPProxy.should_start = False)
+* Use dummy authenticator for ease of testing. Update following in jupyterhub_config file
+    - c.JupyterHub.authenticator_class = 'dummyauthenticator.DummyAuthenticator'
+    - c.DummyAuthenticator.password = "your strong password"
+

docs/Makefile

@@ -2,7 +2,7 @@
 #
 
 # You can set these variables from the command line.
-SPHINXOPTS    =
+SPHINXOPTS    = "-W"
 SPHINXBUILD   = sphinx-build
 PAPER         =
 BUILDDIR      = build

docs/environment.yml

@@ -1,19 +1,22 @@
+# ReadTheDocs uses the `environment.yaml` so make sure to update that as well
+# if you change the dependencies of JupyterHub in the various `requirements.txt`
 name: jhub_docs
 channels:
   - conda-forge
 dependencies:
 - nodejs
-- python=3.5
+- python=3.6
 - alembic
 - jinja2
 - pamela
 - requests
 - sqlalchemy>=1
-- tornado>=4.1
+- tornado>=5.0
 - traitlets>=4.1
-- sphinx>=1.4, !=1.5.4
+- sphinx>=1.7
-- sphinx_rtd_theme
 - pip:
-  - jupyter_alabaster_theme
   - python-oauth2
   - recommonmark==0.4.0
+  - async_generator
+  - prometheus_client
+  - attrs>=17.4.0

docs/requirements.txt

@@ -1,3 +1,5 @@
+# ReadTheDocs uses the `environment.yaml` so make sure to update that as well
+# if you change this file
 -r ../requirements.txt
-sphinx>=1.4
+sphinx>=1.7
 recommonmark==0.4.0

docs/rest-api.yml

@@ -3,7 +3,7 @@ swagger: '2.0'
 info:
   title: JupyterHub
   description: The REST API for JupyterHub
-  version: 0.8.0dev
+  version: 0.9.4
   license:
     name: BSD-3-Clause
 schemes:
@@ -240,18 +240,47 @@ paths:
           description: The user's notebook named-server has stopped
         '202':
           description: The user's notebook named-server has not yet stopped as it is taking a while to stop
-  /users/{name}/admin-access:
+  /users/{name}/tokens:
-    post:
+    get:
-      summary: Grant admin access to this user's notebook server
+      summary: List tokens for the user
-      parameters:
-        - name: name
-          description: username
-          in: path
-          required: true
-          type: string
       responses:
         '200':
-          description: Sets a cookie granting the requesting administrator access to the user's notebook server
+          description: The list of tokens
+          schema:
+            type: array
+            items:
+              $ref: '#/definitions/Token'
+    post:
+      summary: Create a new token for the user
+      parameters:
+        - name: expires_in
+          type: number
+          required: false
+          in: body
+          description: lifetime (in seconds) after which the requested token will expire.
+        - name: note
+          type: string
+          required: false
+          in: body
+          description: A note attached to the token for future bookkeeping
+      responses:
+        '201':
+          description: The newly created token
+          schema:
+            $ref: '#/definitions/Token'
+  /users/{name}/tokens/{token_id}:
+    get:
+      summary: Get the model for a token by id
+      responses:
+        '200':
+          description: The info for the new token
+          schema:
+            $ref: '#/definitions/Token'
+    delete:
+      summary: Delete (revoke) a token by id
+      responses:
+        '204':
+          description: The token has been deleted
   /user:
     summary: Return authenticated user's model
     description:
@@ -588,12 +617,55 @@ definitions:
         description: The user's notebook server's base URL, if running; null if not.
       pending:
         type: string
-        enum: ["spawn", "stop"]
+        enum: ["spawn", "stop", null]
         description: The currently pending action, if any
       last_activity:
         type: string
         format: date-time
         description: Timestamp of last-seen activity from the user
+      servers:
+        type: object
+        description: The active servers for this user.
+        items:
+          schema:
+            $ref: '#/definitions/Server'
+  Server:
+    type: object
+    properties:
+      name:
+        type: string
+        description: The server's name. The user's default server has an empty name ('')
+      ready:
+        type: boolean
+        description: |
+          Whether the server is ready for traffic.
+          Will always be false when any transition is pending.
+      pending:
+        type: string
+        enum: ["spawn", "stop", null]
+        description: |
+          The currently pending action, if any.
+          A server is not ready if an action is pending.
+      url:
+        type: string
+        description: |
+          The URL where the server can be accessed
+          (typically /user/:name/:server.name/).
+      progress_url:
+        type: string
+        description: |
+          The URL for an event-stream to retrieve events during a spawn.
+      started:
+        type: string
+        format: date-time
+        description: UTC timestamp when the server was last started.
+      last_activity:
+        type: string
+        format: date-time
+        description: UTC timestamp last-seen activity on this server.
+      state:
+        type: object
+        description: Arbitrary internal state from this server's spawner.  Only available on the hub's users list or get-user-by-name method, and only if a hub admin.  None otherwise.
   Group:
     type: object
     properties:
@@ -628,3 +700,40 @@ definitions:
         description: The command used to start the service (if managed)
         items:
           type: string
+      info:
+        type: object
+        description: |
+          Additional information a deployment can attach to a service.
+          JupyterHub does not use this field.
+  Token:
+    type: object
+    properties:
+      token:
+        type: string
+        description: The token itself. Only present in responses to requests for a new token.
+      id:
+        type: string
+        description: The id of the API token. Used for modifying or deleting the token.
+      user:
+        type: string
+        description: The user that owns a token (undefined if owned by a service)
+      service:
+        type: string
+        description: The service that owns the token (undefined of owned by a user)
+      note:
+        type: string
+        description: A note about the token, typically describing what it was created for.
+      created:
+        type: string
+        format: date-time
+        description: Timestamp when this token was created
+      expires_at:
+        type: string
+        format: date-time
+        description: Timestamp when this token expires. Null if there is no expiry.
+      last_activity:
+        type: string
+        format: date-time
+        description: |
+          Timestamp of last-seen activity using this token.
+          Can be null if token has never been used.

docs/source/_static/custom.css

@@ -0,0 +1,106 @@
+div#helm-chart-schema h2,
+div#helm-chart-schema h3,
+div#helm-chart-schema h4,
+div#helm-chart-schema h5,
+div#helm-chart-schema h6 {
+    font-family: courier new;
+}
+
+h3, h3 ~ * {
+  margin-left: 3% !important;
+}
+
+h4, h4 ~ * {
+  margin-left: 6% !important;
+}
+
+h5, h5 ~ * {
+  margin-left: 9% !important;
+}
+
+h6, h6 ~ * {
+  margin-left: 12% !important;
+}
+
+h7, h7 ~ * {
+  margin-left: 15% !important;
+}
+
+img.logo {
+  width:100%
+}
+
+.right-next {
+    float: right;
+    max-width: 45%;
+    overflow: auto;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+}
+
+.right-next::after{
+    content: ' »';
+}
+
+.left-prev {
+    float: left;
+    max-width: 45%;
+    overflow: auto;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+}
+
+.left-prev::before{
+    content: '« ';
+}
+
+.prev-next-bottom {
+  margin-top: 3em;
+}
+
+.prev-next-top {
+  margin-bottom: 1em;
+}
+
+/* Sidebar TOC and headers */
+
+div.sphinxsidebarwrapper div {
+    margin-bottom: .8em;
+}
+div.sphinxsidebar h3 {
+    font-size: 1.3em;
+    padding-top: 0px;
+    font-weight: 800;
+    margin-left: 0px !important;
+}
+
+div.sphinxsidebar p.caption {
+    font-size: 1.2em;
+    margin-bottom: 0px;
+    margin-left: 0px !important;
+    font-weight: 900;
+    color: #767676;
+}
+
+div.sphinxsidebar ul {
+    font-size: .8em;
+    margin-top: 0px;
+    padding-left: 3%;
+    margin-left: 0px !important;
+}
+
+div.relations ul {
+    font-size: 1em;
+    margin-left: 0px !important;
+}
+
+div#searchbox form {
+    margin-left: 0px !important;
+}
+
+/* body elements */
+.toctree-wrapper span.caption-text {
+    color: #767676;
+    font-style: italic;
+    font-weight: 300;
+}

docs/source/_templates/navigation.html

@@ -0,0 +1,16 @@
+{# Custom template for navigation.html
+
+   alabaster theme does not provide blocks for titles to
+   be overridden so this custom theme handles title and
+   toctree for sidebar
+#}
+<h3>{{ _('Table of Contents') }}</h3>
+{{ toctree(includehidden=theme_sidebar_includehidden, collapse=theme_sidebar_collapse) }}
+{% if theme_extra_nav_links %}
+<hr />
+<ul>
+    {% for text, uri in theme_extra_nav_links.items() %}
+    <li class="toctree-l1"><a href="{{ uri }}">{{ text }}</a></li>
+    {% endfor %}
+</ul>
+{% endif %}

docs/source/_templates/page.html

@@ -0,0 +1,30 @@
+{% extends '!page.html' %}
+
+{# Custom template for page.html
+
+   Alabaster theme does not provide blocks for prev/next at bottom of each page.
+   This is _in addition_ to the prev/next in the  sidebar. The "Prev/Next" text
+   or symbols are handled by CSS classes in _static/custom.css
+#}
+
+{% macro prev_next(prev, next, prev_title='', next_title='') %}
+  {%- if prev %}
+     <a class='left-prev' href="{{ prev.link|e }}" title="{{ _('previous chapter')}}">{{ prev_title or prev.title }}</a>
+  {%- endif %}
+  {%- if next %}
+     <a class='right-next' href="{{ next.link|e }}" title="{{ _('next chapter')}}">{{ next_title or next.title }}</a>
+  {%- endif %}
+  <div style='clear:both;'></div>
+{% endmacro %}
+
+
+{% block body %}
+  <div class='prev-next-top'>
+    {{ prev_next(prev, next, 'Previous', 'Next') }}
+  </div>
+
+  {{super()}}
+  <div class='prev-next-bottom'>
+    {{ prev_next(prev, next) }}
+  </div>
+{% endblock %}

docs/source/_templates/relations.html

@@ -0,0 +1,17 @@
+{# Custom template for relations.html
+
+   alabaster theme does not provide previous/next page by default
+#}
+<div class="relations">
+<h3>Navigation</h3>
+<ul>
+  <li><a href="{{ pathto(master_doc) }}">Documentation Home</a><ul>
+  {%- if prev %}
+  <li><a href="{{ prev.link|e }}" title="Previous">Previous topic</a></li>
+  {%- endif %}
+  {%- if next %}
+  <li><a href="{{ next.link|e }}" title="Next">Next topic</a></li>
+  {%- endif %}
+  </ul>
+</ul>
+</div>

docs/source/changelog.md

@@ -7,6 +7,172 @@ command line for details.
 
 ## [Unreleased]
 
+## 0.9
+
+### [0.9.4] 2018-09-24
+
+JupyterHub 0.9.4 is a small bugfix release.
+
+- Fixes an  issue that required all running user servers to be restarted
+  when performing an upgrade from 0.8 to 0.9.
+- Fixes content-type for API endpoints back to `application/json`.
+  It was `text/html` in 0.9.0-0.9.3.
+
+### [0.9.3] 2018-09-12
+
+JupyterHub 0.9.3 contains small bugfixes and improvements
+
+- Fix token page and model handling of `expires_at`.
+  This field was missing from the REST API model for tokens
+  and could cause the token page to not render
+- Add keep-alive to progress event stream to avoid proxies dropping
+  the connection due to inactivity
+- Documentation and example improvements
+- Disable quit button when using notebook 5.6
+- Prototype new feature (may change prior to 1.0):
+  pass requesting Handler to Spawners during start,
+  accessible as `self.handler`
+
+### [0.9.2] 2018-08-10
+
+JupyterHub 0.9.2 contains small bugfixes and improvements.
+
+- Documentation and example improvements
+- Add `Spawner.consecutive_failure_limit` config for aborting the Hub if too many spawns fail in a row.
+- Fix for handling SIGTERM when run with asyncio (tornado 5)
+- Windows compatibility fixes
+
+
+### [0.9.1] 2018-07-04
+
+JupyterHub 0.9.1 contains a number of small bugfixes on top of 0.9.
+
+- Use a PID file for the proxy to decrease the likelihood that a leftover proxy process will prevent JupyterHub from restarting
+- `c.LocalProcessSpawner.shell_cmd` is now configurable
+- API requests to stopped servers (requests to the hub for `/user/:name/api/...`) fail with 404 rather than triggering a restart of the server
+- Compatibility fix for notebook 5.6.0 which will introduce further
+  security checks for local connections
+- Managed services always use localhost to talk to the Hub if the Hub listening on all interfaces
+- When using a URL prefix, the Hub route will be `JupyterHub.base_url` instead of unconditionally `/`
+- additional fixes and improvements
+
+### [0.9.0] 2018-06-15
+
+JupyterHub 0.9 is a major upgrade of JupyterHub.
+There are several changes to the database schema,
+so make sure to backup your database and run:
+
+    jupyterhub upgrade-db
+
+after upgrading jupyterhub.
+
+The biggest change for 0.9 is the switch to asyncio coroutines everywhere
+instead of tornado coroutines. Custom Spawners and Authenticators are still
+free to use tornado coroutines for async methods, as they will continue to
+work. As part of this upgrade, JupyterHub 0.9 drops support for Python < 3.5
+and tornado < 5.0.
+
+
+#### Changed
+
+- Require Python >= 3.5
+- Require tornado >= 5.0
+- Use asyncio coroutines throughout
+- Set status 409 for conflicting actions instead of 400,
+  e.g. creating users or groups that already exist.
+- timestamps in REST API continue to be UTC, but now include 'Z' suffix
+  to identify them as such.
+- REST API User model always includes `servers` dict,
+  not just when named servers are enabled.
+- `server` info is no longer available to oauth identification endpoints,
+  only user info and group membership.
+- `User.last_activity` may be None if a user has not been seen,
+  rather than starting with the user creation time
+  which is now separately stored as `User.created`.
+- static resources are now found in `$PREFIX/share/jupyterhub` instead of `share/jupyter/hub` for improved consistency.
+- Deprecate `.extra_log_file` config. Use pipe redirection instead:
+
+      jupyterhub &>> /var/log/jupyterhub.log
+
+- Add `JupyterHub.bind_url` config for setting the full bind URL of the proxy.
+  Sets ip, port, base_url all at once.
+- Add `JupyterHub.hub_bind_url` for setting the full host+port of the Hub.
+  `hub_bind_url` supports unix domain sockets, e.g.
+  `unix+http://%2Fsrv%2Fjupyterhub.sock`
+- Deprecate `JupyterHub.hub_connect_port` config in favor of `JupyterHub.hub_connect_url`. `hub_connect_ip` is not deprecated
+  and can still be used in the common case where only the ip address of the hub differs from the bind ip.
+
+#### Added
+
+- Spawners can define a `.progress` method which should be an async generator.
+  The generator should yield events of the form:
+  ```python
+  {
+    "message": "some-state-message",
+    "progress": 50,
+  }
+  ```
+  These messages will be shown with a progress bar on the spawn-pending page.
+  The `async_generator` package can be used to make async generators
+  compatible with Python 3.5.
+- track activity of individual API tokens
+- new REST API for managing API tokens at `/hub/api/user/tokens[/token-id]`
+- allow viewing/revoking tokens via token page
+- User creation time is available in the REST API as `User.created`
+- Server start time is stored as `Server.started`
+- `Spawner.start` may return a URL for connecting to a notebook instead of `(ip, port)`. This enables Spawners to launch servers that setup their own HTTPS.
+- Optimize database performance by disabling sqlalchemy expire_on_commit by default.
+- Add `python -m jupyterhub.dbutil shell` entrypoint for quickly
+  launching an IPython session connected to your JupyterHub database.
+- Include `User.auth_state` in user model on single-user REST endpoints for admins only.
+- Include `Server.state` in server model on REST endpoints for admins only.
+- Add `Authenticator.blacklist` for blacklisting users instead of whitelisting.
+- Pass `c.JupyterHub.tornado_settings['cookie_options']` down to Spawners
+  so that cookie options (e.g. `expires_days`) can be set globally for the whole application.
+- SIGINFO (`ctrl-t`) handler showing the current status of all running threads,
+  coroutines, and CPU/memory/FD consumption.
+- Add async `Spawner.get_options_form` alternative to `.options_form`, so it can be a coroutine.
+- Add `JupyterHub.redirect_to_server` config to govern whether
+  users should be sent to their server on login or the JuptyerHub home page.
+- html page templates can be more easily customized and extended.
+- Allow registering external OAuth clients for using the Hub as an OAuth provider.
+- Add basic prometheus metrics at `/hub/metrics` endpoint.
+- Add session-id cookie, enabling immediate revocation of login tokens.
+- Authenticators may specify that users are admins by specifying the `admin` key when return the user model as a dict.
+- Added "Start All" button to admin page for launching all user servers at once.
+- Services have an `info` field which is a dictionary.
+  This is accessible via the REST API.
+- `JupyterHub.extra_handlers` allows defining additional tornado RequestHandlers attached to the Hub.
+- API tokens may now expire.
+  Expiry is available in the REST model as `expires_at`,
+  and settable when creating API tokens by specifying `expires_in`.
+
+
+#### Fixed
+
+- Remove green from theme to improve accessibility
+- Fix error when proxy deletion fails due to route already being deleted
+- clear `?redirects` from URL on successful launch
+- disable send2trash by default, which is rarely desirable for jupyterhub
+- Put PAM calls in a thread so they don't block the main application
+  in cases where PAM is slow (e.g. LDAP).
+- Remove implicit spawn from login handler,
+  instead relying on subsequent request for `/user/:name` to trigger spawn.
+- Fixed several inconsistencies for initial redirects,
+  depending on whether server is running or not and whether the user is logged in or not.
+- Admin requests for  `/user/:name` (when admin-access is enabled) launch the right server if it's not running instead of redirecting to their own.
+- Major performance improvement starting up JupyterHub with many users,
+  especially when most are inactive.
+- Various fixes in race conditions and performance improvements with the default proxy.
+- Fixes for CORS headers
+- Stop setting `.form-control` on spawner form inputs unconditionally.
+- Better recovery from database errors and database connection issues
+  without having to restart the Hub.
+- Fix handling of `~` character in usernames.
+- Fix jupyterhub startup when `getpass.getuser()` would fail,
+  e.g. due to missing entry in passwd file in containers.
+
+
 ## 0.8
 
 ### [0.8.1] 2017-11-07
@@ -63,7 +229,7 @@ in your Dockerfile is sufficient.
 
   ```python
   {
-      'username': 'name'
+      'username': 'name',
       'state': {}
   }
   ```
@@ -260,7 +426,12 @@ Fix removal of `/login` page in 0.4.0, breaking some OAuth providers.
 First preview release
 
 
-[Unreleased]: https://github.com/jupyterhub/jupyterhub/compare/0.8.1...HEAD
+[Unreleased]: https://github.com/jupyterhub/jupyterhub/compare/0.9.4...HEAD
+[0.9.4]: https://github.com/jupyterhub/jupyterhub/compare/0.9.3...0.9.4
+[0.9.3]: https://github.com/jupyterhub/jupyterhub/compare/0.9.2...0.9.3
+[0.9.2]: https://github.com/jupyterhub/jupyterhub/compare/0.9.1...0.9.2
+[0.9.1]: https://github.com/jupyterhub/jupyterhub/compare/0.9.0...0.9.1
+[0.9.0]: https://github.com/jupyterhub/jupyterhub/compare/0.8.1...0.9.0
 [0.8.1]: https://github.com/jupyterhub/jupyterhub/compare/0.8.0...0.8.1
 [0.8.0]: https://github.com/jupyterhub/jupyterhub/compare/0.7.2...0.8.0
 [0.7.2]: https://github.com/jupyterhub/jupyterhub/compare/0.7.1...0.7.2

docs/source/conf.py

@@ -21,7 +21,6 @@ extensions = [
     'sphinx.ext.intersphinx',
     'sphinx.ext.napoleon',
     'autodoc_traits',
-    'jupyter_alabaster_theme',
 ]
 
 templates_path = ['_templates']
@@ -36,12 +35,14 @@ author = u'Project Jupyter team'
 
 # Autopopulate version
 from os.path import dirname
+
 docs = dirname(dirname(__file__))
 root = dirname(docs)
 sys.path.insert(0, root)
 sys.path.insert(0, os.path.join(docs, 'sphinxext'))
 
 import jupyterhub
+
 # The short X.Y version.
 version = '%i.%i' % jupyterhub.version_info[:2]
 # The full version, including alpha/beta/rc tags.
@@ -57,81 +58,86 @@ default_role = 'literal'
 
 # -- Source -------------------------------------------------------------
 
-source_parsers = {
+source_parsers = {'.md': 'recommonmark.parser.CommonMarkParser'}
-    '.md': 'recommonmark.parser.CommonMarkParser',
-}
 
 source_suffix = ['.rst', '.md']
-#source_encoding = 'utf-8-sig'
+# source_encoding = 'utf-8-sig'
 
 # -- Options for HTML output ----------------------------------------------
 
 # The theme to use for HTML and HTML Help pages.
-html_theme = 'jupyter_alabaster_theme'
+html_theme = 'alabaster'
 
-#html_theme_options = {}
+html_logo = '_static/images/logo/logo.png'
-#html_theme_path = []
+html_favicon = '_static/images/logo/favicon.ico'
-#html_title = None
-#html_short_title = None
-#html_logo = None
-#html_favicon = None
 
 # Paths that contain custom static files (such as style sheets)
 html_static_path = ['_static']
 
-#html_extra_path = []
+html_theme_options = {
-#html_last_updated_fmt = '%b %d, %Y'
+    'show_related': True,
-#html_use_smartypants = True
+    'description': 'Documentation for JupyterHub',
-#html_sidebars = {}
+    'github_user': 'jupyterhub',
-#html_additional_pages = {}
+    'github_repo': 'jupyterhub',
-#html_domain_indices = True
+    'github_banner': False,
-#html_use_index = True
+    'github_button': True,
-#html_split_index = False
+    'github_type': 'star',
-#html_show_sourcelink = True
+    'show_powered_by': False,
-#html_show_sphinx = True
+    'extra_nav_links': {
-#html_show_copyright = True
+        'GitHub Repo': 'http://github.com/jupyterhub/jupyterhub',
-#html_use_opensearch = ''
+        'Issue Tracker': 'http://github.com/jupyterhub/jupyterhub/issues',
-#html_file_suffix = None
+    },
-#html_search_language = 'en'
+}
-#html_search_options = {'type': 'default'}
+
-#html_search_scorer = 'scorer.js'
+html_sidebars = {
+    '**': [
+        'about.html',
+        'searchbox.html',
+        'navigation.html',
+        'relations.html',
+        'sourcelink.html',
+    ]
+}
+
 htmlhelp_basename = 'JupyterHubdoc'
 
 # -- Options for LaTeX output ---------------------------------------------
 
 latex_elements = {
-#'papersize': 'letterpaper',
+    # 'papersize': 'letterpaper',
-#'pointsize': '10pt',
+    # 'pointsize': '10pt',
-#'preamble': '',
+    # 'preamble': '',
-#'figure_align': 'htbp',
+    # 'figure_align': 'htbp',
 }
 
 # Grouping the document tree into LaTeX files. List of tuples
 # (source start file, target name, title,
 #  author, documentclass [howto, manual, or own class]).
 latex_documents = [
-  (master_doc, 'JupyterHub.tex', u'JupyterHub Documentation',
+    (
-   u'Project Jupyter team', 'manual'),
+        master_doc,
+        'JupyterHub.tex',
+        u'JupyterHub Documentation',
+        u'Project Jupyter team',
+        'manual',
+    )
 ]
 
-#latex_logo = None
+# latex_logo = None
-#latex_use_parts = False
+# latex_use_parts = False
-#latex_show_pagerefs = False
+# latex_show_pagerefs = False
-#latex_show_urls = False
+# latex_show_urls = False
-#latex_appendices = []
+# latex_appendices = []
-#latex_domain_indices = True
+# latex_domain_indices = True
 
 
 # -- manual page output -------------------------------------------------
 
 # One entry per manual page. List of tuples
 # (source start file, name, description, authors, manual section).
-man_pages = [
+man_pages = [(master_doc, 'jupyterhub', u'JupyterHub Documentation', [author], 1)]
-    (master_doc, 'jupyterhub', u'JupyterHub Documentation',
-     [author], 1)
-]
 
-#man_show_urls = False
+# man_show_urls = False
 
 
 # -- Texinfo output -----------------------------------------------------
@@ -140,15 +146,21 @@ man_pages = [
 # (source start file, target name, title, author,
 #  dir menu entry, description, category)
 texinfo_documents = [
-  (master_doc, 'JupyterHub', u'JupyterHub Documentation',
+    (
-   author, 'JupyterHub', 'One line description of project.',
+        master_doc,
-   'Miscellaneous'),
+        'JupyterHub',
+        u'JupyterHub Documentation',
+        author,
+        'JupyterHub',
+        'One line description of project.',
+        'Miscellaneous',
+    )
 ]
 
-#texinfo_appendices = []
+# texinfo_appendices = []
-#texinfo_domain_indices = True
+# texinfo_domain_indices = True
-#texinfo_show_urls = 'footnote'
+# texinfo_show_urls = 'footnote'
-#texinfo_no_detailmenu = False
+# texinfo_no_detailmenu = False
 
 
 # -- Epub output --------------------------------------------------------
@@ -170,13 +182,12 @@ intersphinx_mapping = {'https://docs.python.org/3/': None}
 
 on_rtd = os.environ.get('READTHEDOCS', None) == 'True'
 if not on_rtd:
-    import jupyter_alabaster_theme
+    html_theme = 'alabaster'
-    html_theme = 'jupyter_alabaster_theme'
-    html_theme_path = [jupyter_alabaster_theme.get_path()]
 else:
     # readthedocs.org uses their theme by default, so no need to specify it
     # build rest-api, since RTD doesn't run make
     from subprocess import check_call as sh
+
     sh(['make', 'rest-api'], cwd=docs)
 
 # -- Spell checking -------------------------------------------------------
@@ -188,4 +199,4 @@ except ImportError:
 else:
     extensions.append("sphinxcontrib.spelling")
 
-spelling_word_list_filename='spelling_wordlist.txt'
+spelling_word_list_filename = 'spelling_wordlist.txt'

docs/source/contributor-list.md

@@ -3,38 +3,65 @@
 Project Jupyter thanks the following people for their help and
 contribution on JupyterHub:
 
+- adelcast
 - Analect
 - anderbubble
+- anikitml
+- ankitksharma
 - apetresc
+- athornton
 - barrachri
+- BerserkerTroll
 - betatim
 - Carreau
+- cfournie
 - charnpreetsingh
+- chicovenancio
+- cikao
 - ckald
+- cmoscardi
+- consideRatio
+- cqzlxl
 - CRegenschein
 - cwaldbieser
 - danielballen
 - danoventa
 - daradib
+- darky2004
 - datapolitan
 - dblockow-d2dcrc
 - DeepHorizons
+- DerekHeldtWerle
 - dhirschfeld
 - dietmarw
+- dingc3
 - dmartzol
 - DominicFollettSmith
 - dsblank
+- dtaniwaki
+- echarles
 - ellisonbg
+- emmanuel
 - evanlinde
 - Fokko
 - fperez
+- franga2000
+- GladysNalvarte
+- glenak1911
+- gweis
 - iamed18
+- jamescurtin
 - JamiesHQ
+- JasonJWilliamsNY
 - jbweston
 - jdavidheiser
 - jencabral
 - jhamrick
+- jkinkead
+- johnkpark
 - josephtate
+- jzf2101
+- karfai
 - kinuax
 - KrishnaPG
 - kroq-gar78
@@ -44,27 +71,44 @@ contribution on JupyterHub:
 - minrk
 - mistercrunch
 - Mistobaan
+- mpacer
 - mwmarkland
+- ndly
 - nthiery
+- nxg
 - ObiWahn
 - ozancaglayan
+- paccorsi
 - parente
 - PeterDaveHello
 - peterruppel
+- phill84
 - pjamason
 - prasadkatti
 - rafael-ladislau
+- rcthomas
 - rgbkrk
+- rkdarst
 - robnagler
+- rschroll
 - ryanlovett
+- sangramga
 - Scrypy
+- schon
 - shreddd
+- Siecje
+- smiller5678
 - spoorthyv
 - ssanderson
+- summerswallow
+- syutbai
 - takluyver
 - temogen
 - ThomasMChen
+- Thoralf Gutierrez
+- timfreund
 - TimShawver
+- tklever
 - Todd-Z-Li
 - toobaz
 - tsaeger

docs/source/gallery-jhub-deployments.md

@@ -151,9 +151,9 @@ easy to do with RStudio too.
 - https://getcarina.com/blog/learning-how-to-whale/
 - http://carolynvanslyck.com/talk/carina/jupyterhub/#/
 
-### Red Hat
+### jcloud.io
-
+- Open to public JupyterHub server
-
+    - https://jcloud.io
 ## Miscellaneous
 
 - https://medium.com/@ybarraud/setting-up-jupyterhub-with-sudospawner-and-anaconda-844628c0dbee#.rm3yt87e1

docs/source/getting-started/networking-basics.md

@@ -35,6 +35,10 @@ Configuring only the main IP and port of JupyterHub should be sufficient for
 most deployments of JupyterHub. However, more customized scenarios may need
 additional networking details to be configured.
 
+Note that `c.JupyterHub.ip` and `c.JupyterHub.port` are single values,
+not tuples or lists – JupyterHub listens to only a single IP address and
+port.
+
 ## Set the Proxy's REST API communication URL (optional)
 
 By default, this REST API listens on port 8081 of `localhost` only.
@@ -86,3 +90,12 @@ configuration for, e.g. docker, is:
 c.JupyterHub.hub_ip = '0.0.0.0'  # listen on all interfaces
 c.JupyterHub.hub_connect_ip = '10.0.1.4'  # ip as seen on the docker network. Can also be a hostname.
 ```
+
+## Adjusting the hub's URL
+
+The hub will most commonly be running on a hostname of its own.  If it
+is not – for example, if the hub is being reverse-proxied and being
+exposed at a URL such as `https://proxy.example.org/jupyter/` – then
+you will need to tell JupyterHub the base URL of the service.  In such
+a case, it is both necessary and sufficient to set
+`c.JupyterHub.base_url = '/jupyter/'` in the configuration.

docs/source/getting-started/security-basics.rst

@@ -45,7 +45,7 @@ is important that these files be put in a secure location on your server, where
 they are not readable by regular users.
 
 If you are using a **chain certificate**, see also chained certificate for SSL
-in the JupyterHub `troubleshooting FAQ <troubleshooting>`_.
+in the JupyterHub `Troubleshooting FAQ <../troubleshooting.html>`_.
 
 Using letsencrypt
 ~~~~~~~~~~~~~~~~~
@@ -72,8 +72,13 @@ would be the needed configuration:
 If SSL termination happens outside of the Hub
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-In certain cases, e.g. behind `SSL termination in NGINX <https://www.nginx.com/resources/admin-guide/nginx-ssl-termination/>`_,
+In certain cases, for example if the hub is running behind a reverse proxy, and
-allowing no SSL running on the hub may be the desired configuration option.
+`SSL termination is being provided by NGINX <https://www.nginx.com/resources/admin-guide/nginx-ssl-termination/>`_,
+it is reasonable to run the hub without SSL.
+
+To achieve this, simply omit the configuration settings
+``c.JupyterHub.ssl_key`` and ``c.JupyterHub.ssl_cert``
+(setting them to ``None`` does not have the same effect, and is an error).
 
 .. _cookie-secret:
 

docs/source/getting-started/services-basics.md

@@ -88,7 +88,7 @@ c.JupyterHub.services = [
     {
         'name': 'cull-idle',
         'admin': True,
-        'command': 'python cull_idle_servers.py --timeout=3600'.split(),
+        'command': 'python3 cull_idle_servers.py --timeout=3600'.split(),
     }
 ]
 ```
@@ -115,7 +115,7 @@ variable. Run `cull_idle_servers.py` manually.
 
 ```bash
     export JUPYTERHUB_API_TOKEN='token'
-    python cull_idle_servers.py [--timeout=900] [--url=http://127.0.0.1:8081/hub/api]
+    python3 cull_idle_servers.py [--timeout=900] [--url=http://127.0.0.1:8081/hub/api]
 ```
 
 [cull_idle_servers]: https://github.com/jupyterhub/jupyterhub/blob/master/examples/cull-idle/cull_idle_servers.py

docs/source/index.rst

@@ -19,7 +19,7 @@ Three subsystems make up JupyterHub:
 
 JupyterHub performs the following functions:
 
-- The Hub spawns a proxy
+- The Hub launches a proxy
 - The proxy forwards all requests to the Hub by default
 - The Hub handles user login and spawns single-user servers on demand
 - The Hub configures the proxy to forward URL prefixes to the single-user
@@ -58,7 +58,12 @@ Contents
 * :doc:`reference/services`
 * :doc:`reference/rest`
 * :doc:`reference/upgrading`
+* :doc:`reference/templates`
+* :doc:`reference/config-user-env`
 * :doc:`reference/config-examples`
+* :doc:`reference/config-ghoauth`
+* :doc:`reference/config-proxy`
+* :doc:`reference/config-sudo`
 
 **API Reference**
 

docs/source/quickstart-docker.rst

@@ -37,7 +37,7 @@ If you want to run docker on a computer that has a public IP then you should
 (as in MUST) **secure it with ssl** by adding ssl options to your docker
 configuration or using a ssl enabled proxy.
 
-`Mounting volumes <https://docs.docker.com/engine/userguide/containers/dockervolumes/>`_
+`Mounting volumes <https://docs.docker.com/engine/admin/volumes/volumes/>`_
 will allow you to store data outside the docker image (host system) so it will
 be persistent, even when you start a new image.
 

docs/source/quickstart.md

@@ -5,20 +5,27 @@
 Before installing JupyterHub, you will need:
 
 - a Linux/Unix based system
-- [Python](https://www.python.org/downloads/) 3.4 or greater. An understanding
+- [Python](https://www.python.org/downloads/) 3.5 or greater. An understanding
   of using [`pip`](https://pip.pypa.io/en/stable/) or
   [`conda`](https://conda.io/docs/get-started.html) for
   installing Python packages is helpful.
 - [nodejs/npm](https://www.npmjs.com/). [Install nodejs/npm](https://docs.npmjs.com/getting-started/installing-node),
-  using your operating system's package manager. For example, install on Linux
+  using your operating system's package manager.
-  Debian/Ubuntu using:
 
-  ```bash
+  * If you are using **`conda`**, the nodejs and npm dependencies will be installed for
-  sudo apt-get install npm nodejs-legacy
+    you by conda.
-  ```
+
+  * If you are using **`pip`**, install a recent version of
+    [nodejs/npm](https://docs.npmjs.com/getting-started/installing-node).
+    For example, install it on Linux (Debian/Ubuntu) using:
+
+    ```
+    sudo apt-get install npm nodejs-legacy
+    ```
+          
+    The `nodejs-legacy` package installs the `node` executable and is currently
+    required for npm to work on Debian/Ubuntu.
 
-  The `nodejs-legacy` package installs the `node` executable and is currently
-  required for `npm` to work on Debian/Ubuntu.
 - TLS certificate and key for HTTPS communication
 - Domain name
 

docs/source/reference/authenticators.md

@@ -38,6 +38,8 @@ with any provider, is also available.
 
 - ldapauthenticator for LDAP
 - tmpauthenticator for temporary accounts
+- For Shibboleth, [jhub_shibboleth_auth](https://github.com/gesiscss/jhub_shibboleth_auth)
+  and [jhub_remote_user_authenticator](https://github.com/cwaldbieser/jhub_remote_user_authenticator)
 
 ## Technical Overview of Authentication
 
@@ -145,7 +147,7 @@ If such state should be persisted, `.authenticate()` should return a dictionary
 
 ```python
 {
-  'username': 'name',
+  'name': username,
   'auth_state': {
     'key': 'value',
   }
@@ -206,7 +208,13 @@ class MyAuthenticator(Authenticator):
         spawner.environment['UPSTREAM_TOKEN'] = auth_state['upstream_token']
 ```
 
+## pre_spawn_start and post_spawn_stop hooks
 
+Authenticators uses two hooks, [pre_spawn_start(user, spawner)][] and
+[post_spawn_stop(user, spawner)][] to add pass additional state information
+between the authenticator and a spawner. These hooks are typically used auth-related
+startup, i.e. opening a PAM session, and auth-related cleanup, i.e. closing a
+PAM session.
 
 ## JupyterHub as an OAuth provider
 
@@ -218,5 +226,5 @@ Beginning with version 0.8, JupyterHub is an OAuth provider.
 [OAuth]: https://en.wikipedia.org/wiki/OAuth
 [GitHub OAuth]: https://developer.github.com/v3/oauth/
 [OAuthenticator]: https://github.com/jupyterhub/oauthenticator
-[pre_spawn_start(user, spawner)]: http://jupyterhub.readthedocs.io/en/latest/api/auth.html#jupyterhub.auth.Authenticator.pre_spawn_start
+[pre_spawn_start(user, spawner)]: https://jupyterhub.readthedocs.io/en/latest/api/auth.html#jupyterhub.auth.Authenticator.pre_spawn_start
-[post_spawn_stop(user, spawner)]: http://jupyterhub.readthedocs.io/en/latest/api/auth.html#jupyterhub.auth.Authenticator.post_spawn_stop
+[post_spawn_stop(user, spawner)]: https://jupyterhub.readthedocs.io/en/latest/api/auth.html#jupyterhub.auth.Authenticator.post_spawn_stop

docs/source/reference/config-examples.md

@@ -1,272 +1,8 @@
 # Configuration examples
 
-This section provides examples, including configuration files and tips, for the
+The following sections provide examples, including configuration files and tips, for the
-following configurations:
+following:
 
-- Using GitHub OAuth
+- Configuring GitHub OAuth
-- Using nginx reverse proxy
+- Using reverse proxy (nginx and Apache)
-
+- Run JupyterHub without root privileges using `sudo`
-## Using GitHub OAuth
-
-In this example, we show a configuration file for a fairly standard JupyterHub
-deployment with the following assumptions:
-
-* Running JupyterHub on a single cloud server
-* Using SSL on the standard HTTPS port 443
-* Using GitHub OAuth (using oauthenticator) for login
-* Users exist locally on the server
-* Users' notebooks to be served from `~/assignments` to allow users to browse
-  for notebooks within other users' home directories
-* You want the landing page for each user to be a `Welcome.ipynb` notebook in
-  their assignments directory.
-* All runtime files are put into `/srv/jupyterhub` and log files in `/var/log`.
-
-The `jupyterhub_config.py` file would have these settings:
-
-```python
-# jupyterhub_config.py file
-c = get_config()
-
-import os
-pjoin = os.path.join
-
-runtime_dir = os.path.join('/srv/jupyterhub')
-ssl_dir = pjoin(runtime_dir, 'ssl')
-if not os.path.exists(ssl_dir):
-    os.makedirs(ssl_dir)
-
-# Allows multiple single-server per user
-c.JupyterHub.allow_named_servers = True
-
-# https on :443
-c.JupyterHub.port = 443
-c.JupyterHub.ssl_key = pjoin(ssl_dir, 'ssl.key')
-c.JupyterHub.ssl_cert = pjoin(ssl_dir, 'ssl.cert')
-
-# put the JupyterHub cookie secret and state db
-# in /var/run/jupyterhub
-c.JupyterHub.cookie_secret_file = pjoin(runtime_dir, 'cookie_secret')
-c.JupyterHub.db_url = pjoin(runtime_dir, 'jupyterhub.sqlite')
-# or `--db=/path/to/jupyterhub.sqlite` on the command-line
-
-# use GitHub OAuthenticator for local users
-c.JupyterHub.authenticator_class = 'oauthenticator.LocalGitHubOAuthenticator'
-c.GitHubOAuthenticator.oauth_callback_url = os.environ['OAUTH_CALLBACK_URL']
-
-# create system users that don't exist yet
-c.LocalAuthenticator.create_system_users = True
-
-# specify users and admin
-c.Authenticator.whitelist = {'rgbkrk', 'minrk', 'jhamrick'}
-c.Authenticator.admin_users = {'jhamrick', 'rgbkrk'}
-
-# start single-user notebook servers in ~/assignments,
-# with ~/assignments/Welcome.ipynb as the default landing page
-# this config could also be put in
-# /etc/jupyter/jupyter_notebook_config.py
-c.Spawner.notebook_dir = '~/assignments'
-c.Spawner.args = ['--NotebookApp.default_url=/notebooks/Welcome.ipynb']
-```
-
-Using the GitHub Authenticator requires a few additional
-environment variable to be set prior to launching JupyterHub:
-
-```bash
-export GITHUB_CLIENT_ID=github_id
-export GITHUB_CLIENT_SECRET=github_secret
-export OAUTH_CALLBACK_URL=https://example.com/hub/oauth_callback
-export CONFIGPROXY_AUTH_TOKEN=super-secret
-# append log output to log file /var/log/jupyterhub.log
-jupyterhub -f /etc/jupyterhub/jupyterhub_config.py &>> /var/log/jupyterhub.log
-```
-
-## Using a reverse proxy
-
-In the following example, we show configuration files for a JupyterHub server
-running locally on port `8000` but accessible from the outside on the standard
-SSL port `443`. This could be useful if the JupyterHub server machine is also
-hosting other domains or content on `443`. The goal in this example is to
-satisfy the following:
-
-* JupyterHub is running on a server, accessed *only* via `HUB.DOMAIN.TLD:443`
-* On the same machine, `NO_HUB.DOMAIN.TLD` strictly serves different content,
-  also on port `443`
-* `nginx` or `apache` is used as the public access point (which means that
-  only nginx/apache will bind  to `443`)
-* After testing, the server in question should be able to score at least an A on the
-  Qualys SSL Labs [SSL Server Test](https://www.ssllabs.com/ssltest/)
-
-Let's start out with needed JupyterHub configuration in `jupyterhub_config.py`:
-
-```python
-# Force the proxy to only listen to connections to 127.0.0.1
-c.JupyterHub.ip = '127.0.0.1'
-```
-
-For high-quality SSL configuration, we also generate Diffie-Helman parameters.
-This can take a few minutes:
-
-```bash
-openssl dhparam -out /etc/ssl/certs/dhparam.pem 4096
-```
-
-### nginx
-
-The **`nginx` server config file** is fairly standard fare except for the two
-`location` blocks within the `HUB.DOMAIN.TLD` config file:
-
-```bash
-# top-level http config for websocket headers
-# If Upgrade is defined, Connection = upgrade
-# If Upgrade is empty, Connection = close
-map $http_upgrade $connection_upgrade {
-    default upgrade;
-    ''      close;
-}
-
-# HTTP server to redirect all 80 traffic to SSL/HTTPS
-server {
-    listen 80;
-    server_name HUB.DOMAIN.TLD;
-
-    # Tell all requests to port 80 to be 302 redirected to HTTPS
-    return 302 https://$host$request_uri;
-}
-
-# HTTPS server to handle JupyterHub
-server {
-    listen 443;
-    ssl on;
-
-    server_name HUB.DOMAIN.TLD;
-
-    ssl_certificate /etc/letsencrypt/live/HUB.DOMAIN.TLD/fullchain.pem;
-    ssl_certificate_key /etc/letsencrypt/live/HUB.DOMAIN.TLD/privkey.pem;
-
-    ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
-    ssl_prefer_server_ciphers on;
-    ssl_dhparam /etc/ssl/certs/dhparam.pem;
-    ssl_ciphers 'ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:kEDH+AESGCM:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA:DHE-RSA-AES256-SHA:AES128-GCM-SHA256:AES256-GCM-SHA384:AES128-SHA256:AES256-SHA256:AES128-SHA:AES256-SHA:AES:CAMELLIA:DES-CBC3-SHA:!aNULL:!eNULL:!EXPORT:!DES:!RC4:!MD5:!PSK:!aECDH:!EDH-DSS-DES-CBC3-SHA:!EDH-RSA-DES-CBC3-SHA:!KRB5-DES-CBC3-SHA';
-    ssl_session_timeout 1d;
-    ssl_session_cache shared:SSL:50m;
-    ssl_stapling on;
-    ssl_stapling_verify on;
-    add_header Strict-Transport-Security max-age=15768000;
-
-    # Managing literal requests to the JupyterHub front end
-    location / {
-        proxy_pass http://127.0.0.1:8000;
-        proxy_set_header X-Real-IP $remote_addr;
-        proxy_set_header Host $host;
-        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
-
-        # websocket headers
-        proxy_set_header Upgrade $http_upgrade;
-        proxy_set_header Connection $connection_upgrade;
-    }
-
-    # Managing requests to verify letsencrypt host
-    location ~ /.well-known {
-        allow all;
-    }
-}
-```
-
-If `nginx` is not running on port 443, substitute `$http_host` for `$host` on
-the lines setting the `Host` header.
-
-`nginx` will now be the front facing element of JupyterHub on `443` which means
-it is also free to bind other servers, like `NO_HUB.DOMAIN.TLD` to the same port
-on the same machine and network interface. In fact, one can simply use the same
-server blocks as above for `NO_HUB` and simply add line for the root directory
-of the site as well as the applicable location call:
-
-```bash
-server {
-    listen 80;
-    server_name NO_HUB.DOMAIN.TLD;
-
-    # Tell all requests to port 80 to be 302 redirected to HTTPS
-    return 302 https://$host$request_uri;
-}
-
-server {
-    listen 443;
-    ssl on;
-
-    # INSERT OTHER SSL PARAMETERS HERE AS ABOVE
-    # SSL cert may differ
-
-    # Set the appropriate root directory
-    root /var/www/html
-
-    # Set URI handling
-    location / {
-        try_files $uri $uri/ =404;
-    }
-
-    # Managing requests to verify letsencrypt host
-    location ~ /.well-known {
-        allow all;
-    }
-
-}
-```
-
-Now restart `nginx`, restart the JupyterHub, and enjoy accessing
-`https://HUB.DOMAIN.TLD` while serving other content securely on
-`https://NO_HUB.DOMAIN.TLD`.
-
-
-### Apache
-
-As with nginx above, you can use [Apache](https://httpd.apache.org) as the reverse proxy.
-First, we will need to enable the apache modules that we are going to need:
-
-```bash
-a2enmod ssl rewrite proxy proxy_http proxy_wstunnel
-```
-
-Our Apache configuration is equivalent to the nginx configuration above:
-
-- Redirect HTTP to HTTPS
-- Good SSL Configuration
-- Support for websockets on any proxied URL
-- JupyterHub is running locally at http://127.0.0.1:8000
-
-```bash
-# redirect HTTP to HTTPS
-Listen 80
-<VirtualHost HUB.DOMAIN.TLD:80>
-  ServerName HUB.DOMAIN.TLD
-  Redirect / https://HUB.DOMAIN.TLD/
-</VirtualHost>
-
-Listen 443
-<VirtualHost HUB.DOMAIN.TLD:443>
-
-  ServerName HUB.DOMAIN.TLD
-
-  # configure SSL
-  SSLEngine on
-  SSLCertificateFile /etc/letsencrypt/live/HUB.DOMAIN.TLD/fullchain.pem
-  SSLCertificateKeyFile /etc/letsencrypt/live/HUB.DOMAIN.TLD/privkey.pem
-  SSLProtocol All -SSLv2 -SSLv3
-  SSLOpenSSLConfCmd DHParameters /etc/ssl/certs/dhparam.pem
-  SSLCipherSuite EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH
-
-  # Use RewriteEngine to handle websocket connection upgrades
-  RewriteEngine On
-  RewriteCond %{HTTP:Connection} Upgrade [NC]
-  RewriteCond %{HTTP:Upgrade} websocket [NC]
-  RewriteRule /(.*) ws://127.0.0.1:8000/$1 [P,L]
-
-  <Location "/">
-    # preserve Host header to avoid cross-origin problems
-    ProxyPreserveHost on
-    # proxy to JupyterHub
-    ProxyPass         http://127.0.0.1:8000/
-    ProxyPassReverse  http://127.0.0.1:8000/
-  </Location>
-</VirtualHost>
-```

docs/source/reference/config-ghoauth.md

@@ -0,0 +1,82 @@
+# Configure GitHub OAuth
+
+In this example, we show a configuration file for a fairly standard JupyterHub
+deployment with the following assumptions:
+
+* Running JupyterHub on a single cloud server
+* Using SSL on the standard HTTPS port 443
+* Using GitHub OAuth (using oauthenticator) for login
+* Using the default spawner (to configure other spawners, uncomment and edit
+  `spawner_class` as well as follow the instructions for your desired spawner)
+* Users exist locally on the server
+* Users' notebooks to be served from `~/assignments` to allow users to browse
+  for notebooks within other users' home directories
+* You want the landing page for each user to be a `Welcome.ipynb` notebook in
+  their assignments directory.
+* All runtime files are put into `/srv/jupyterhub` and log files in `/var/log`.
+
+
+The `jupyterhub_config.py` file would have these settings:
+
+```python
+# jupyterhub_config.py file
+c = get_config()
+
+import os
+pjoin = os.path.join
+
+runtime_dir = os.path.join('/srv/jupyterhub')
+ssl_dir = pjoin(runtime_dir, 'ssl')
+if not os.path.exists(ssl_dir):
+    os.makedirs(ssl_dir)
+
+# Allows multiple single-server per user
+c.JupyterHub.allow_named_servers = True
+
+# https on :443
+c.JupyterHub.port = 443
+c.JupyterHub.ssl_key = pjoin(ssl_dir, 'ssl.key')
+c.JupyterHub.ssl_cert = pjoin(ssl_dir, 'ssl.cert')
+
+# put the JupyterHub cookie secret and state db
+# in /var/run/jupyterhub
+c.JupyterHub.cookie_secret_file = pjoin(runtime_dir, 'cookie_secret')
+c.JupyterHub.db_url = pjoin(runtime_dir, 'jupyterhub.sqlite')
+# or `--db=/path/to/jupyterhub.sqlite` on the command-line
+
+# use GitHub OAuthenticator for local users
+c.JupyterHub.authenticator_class = 'oauthenticator.LocalGitHubOAuthenticator'
+c.GitHubOAuthenticator.oauth_callback_url = os.environ['OAUTH_CALLBACK_URL']
+
+# create system users that don't exist yet
+c.LocalAuthenticator.create_system_users = True
+
+# specify users and admin
+c.Authenticator.whitelist = {'rgbkrk', 'minrk', 'jhamrick'}
+c.Authenticator.admin_users = {'jhamrick', 'rgbkrk'}
+
+# uses the default spawner
+# To use a different spawner, uncomment `spawner_class` and set to desired
+# spawner (e.g. SudoSpawner). Follow instructions for desired spawner
+# configuration.
+# c.JupyterHub.spawner_class = 'sudospawner.SudoSpawner'
+
+# start single-user notebook servers in ~/assignments,
+# with ~/assignments/Welcome.ipynb as the default landing page
+# this config could also be put in
+# /etc/jupyter/jupyter_notebook_config.py
+c.Spawner.notebook_dir = '~/assignments'
+c.Spawner.args = ['--NotebookApp.default_url=/notebooks/Welcome.ipynb']
+```
+
+Using the GitHub Authenticator requires a few additional
+environment variable to be set prior to launching JupyterHub:
+
+```bash
+export GITHUB_CLIENT_ID=github_id
+export GITHUB_CLIENT_SECRET=github_secret
+export OAUTH_CALLBACK_URL=https://example.com/hub/oauth_callback
+export CONFIGPROXY_AUTH_TOKEN=super-secret
+# append log output to log file /var/log/jupyterhub.log
+jupyterhub -f /etc/jupyterhub/jupyterhub_config.py &>> /var/log/jupyterhub.log
+```

docs/source/reference/config-proxy.md

@@ -0,0 +1,192 @@
+# Using a reverse proxy
+
+In the following example, we show configuration files for a JupyterHub server
+running locally on port `8000` but accessible from the outside on the standard
+SSL port `443`. This could be useful if the JupyterHub server machine is also
+hosting other domains or content on `443`. The goal in this example is to
+satisfy the following:
+
+* JupyterHub is running on a server, accessed *only* via `HUB.DOMAIN.TLD:443`
+* On the same machine, `NO_HUB.DOMAIN.TLD` strictly serves different content,
+  also on port `443`
+* `nginx` or `apache` is used as the public access point (which means that
+  only nginx/apache will bind  to `443`)
+* After testing, the server in question should be able to score at least an A on the
+  Qualys SSL Labs [SSL Server Test](https://www.ssllabs.com/ssltest/)
+
+Let's start out with needed JupyterHub configuration in `jupyterhub_config.py`:
+
+```python
+# Force the proxy to only listen to connections to 127.0.0.1
+c.JupyterHub.ip = '127.0.0.1'
+```
+
+For high-quality SSL configuration, we also generate Diffie-Helman parameters.
+This can take a few minutes:
+
+```bash
+openssl dhparam -out /etc/ssl/certs/dhparam.pem 4096
+```
+
+## nginx
+
+This **`nginx` config file** is fairly standard fare except for the two
+`location` blocks within the main section for HUB.DOMAIN.tld.
+To create a new site for jupyterhub in your nginx config, make a new file
+in `sites.enabled`, e.g. `/etc/nginx/sites.enabled/jupyterhub.conf`:
+
+```bash
+# top-level http config for websocket headers
+# If Upgrade is defined, Connection = upgrade
+# If Upgrade is empty, Connection = close
+map $http_upgrade $connection_upgrade {
+    default upgrade;
+    ''      close;
+}
+
+# HTTP server to redirect all 80 traffic to SSL/HTTPS
+server {
+    listen 80;
+    server_name HUB.DOMAIN.TLD;
+
+    # Tell all requests to port 80 to be 302 redirected to HTTPS
+    return 302 https://$host$request_uri;
+}
+
+# HTTPS server to handle JupyterHub
+server {
+    listen 443;
+    ssl on;
+
+    server_name HUB.DOMAIN.TLD;
+
+    ssl_certificate /etc/letsencrypt/live/HUB.DOMAIN.TLD/fullchain.pem;
+    ssl_certificate_key /etc/letsencrypt/live/HUB.DOMAIN.TLD/privkey.pem;
+
+    ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
+    ssl_prefer_server_ciphers on;
+    ssl_dhparam /etc/ssl/certs/dhparam.pem;
+    ssl_ciphers 'ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:kEDH+AESGCM:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA:DHE-RSA-AES256-SHA:AES128-GCM-SHA256:AES256-GCM-SHA384:AES128-SHA256:AES256-SHA256:AES128-SHA:AES256-SHA:AES:CAMELLIA:DES-CBC3-SHA:!aNULL:!eNULL:!EXPORT:!DES:!RC4:!MD5:!PSK:!aECDH:!EDH-DSS-DES-CBC3-SHA:!EDH-RSA-DES-CBC3-SHA:!KRB5-DES-CBC3-SHA';
+    ssl_session_timeout 1d;
+    ssl_session_cache shared:SSL:50m;
+    ssl_stapling on;
+    ssl_stapling_verify on;
+    add_header Strict-Transport-Security max-age=15768000;
+
+    # Managing literal requests to the JupyterHub front end
+    location / {
+        proxy_pass http://127.0.0.1:8000;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header Host $host;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+
+        # websocket headers
+        proxy_set_header Upgrade $http_upgrade;
+        proxy_set_header Connection $connection_upgrade;
+    }
+
+    # Managing requests to verify letsencrypt host
+    location ~ /.well-known {
+        allow all;
+    }
+}
+```
+
+If `nginx` is not running on port 443, substitute `$http_host` for `$host` on
+the lines setting the `Host` header.
+
+`nginx` will now be the front facing element of JupyterHub on `443` which means
+it is also free to bind other servers, like `NO_HUB.DOMAIN.TLD` to the same port
+on the same machine and network interface. In fact, one can simply use the same
+server blocks as above for `NO_HUB` and simply add line for the root directory
+of the site as well as the applicable location call:
+
+```bash
+server {
+    listen 80;
+    server_name NO_HUB.DOMAIN.TLD;
+
+    # Tell all requests to port 80 to be 302 redirected to HTTPS
+    return 302 https://$host$request_uri;
+}
+
+server {
+    listen 443;
+    ssl on;
+
+    # INSERT OTHER SSL PARAMETERS HERE AS ABOVE
+    # SSL cert may differ
+
+    # Set the appropriate root directory
+    root /var/www/html
+
+    # Set URI handling
+    location / {
+        try_files $uri $uri/ =404;
+    }
+
+    # Managing requests to verify letsencrypt host
+    location ~ /.well-known {
+        allow all;
+    }
+
+}
+```
+
+Now restart `nginx`, restart the JupyterHub, and enjoy accessing
+`https://HUB.DOMAIN.TLD` while serving other content securely on
+`https://NO_HUB.DOMAIN.TLD`.
+
+
+## Apache
+
+As with nginx above, you can use [Apache](https://httpd.apache.org) as the reverse proxy.
+First, we will need to enable the apache modules that we are going to need:
+
+```bash
+a2enmod ssl rewrite proxy proxy_http proxy_wstunnel
+```
+
+Our Apache configuration is equivalent to the nginx configuration above:
+
+- Redirect HTTP to HTTPS
+- Good SSL Configuration
+- Support for websockets on any proxied URL
+- JupyterHub is running locally at http://127.0.0.1:8000
+
+```bash
+# redirect HTTP to HTTPS
+Listen 80
+<VirtualHost HUB.DOMAIN.TLD:80>
+  ServerName HUB.DOMAIN.TLD
+  Redirect / https://HUB.DOMAIN.TLD/
+</VirtualHost>
+
+Listen 443
+<VirtualHost HUB.DOMAIN.TLD:443>
+
+  ServerName HUB.DOMAIN.TLD
+
+  # configure SSL
+  SSLEngine on
+  SSLCertificateFile /etc/letsencrypt/live/HUB.DOMAIN.TLD/fullchain.pem
+  SSLCertificateKeyFile /etc/letsencrypt/live/HUB.DOMAIN.TLD/privkey.pem
+  SSLProtocol All -SSLv2 -SSLv3
+  SSLOpenSSLConfCmd DHParameters /etc/ssl/certs/dhparam.pem
+  SSLCipherSuite EECDH+AESGCM:EDH+AESGCM:AES256+EECDH:AES256+EDH
+
+  # Use RewriteEngine to handle websocket connection upgrades
+  RewriteEngine On
+  RewriteCond %{HTTP:Connection} Upgrade [NC]
+  RewriteCond %{HTTP:Upgrade} websocket [NC]
+  RewriteRule /(.*) ws://127.0.0.1:8000/$1 [P,L]
+
+  <Location "/">
+    # preserve Host header to avoid cross-origin problems
+    ProxyPreserveHost on
+    # proxy to JupyterHub
+    ProxyPass         http://127.0.0.1:8000/
+    ProxyPassReverse  http://127.0.0.1:8000/
+  </Location>
+</VirtualHost>
+```

docs/source/reference/config-sudo.md

@@ -0,0 +1,254 @@
+# Run JupyterHub without root privileges using `sudo`
+
+**Note:** Setting up `sudo` permissions involves many pieces of system
+configuration. It is quite easy to get wrong and very difficult to debug.
+Only do this if you are very sure you must.
+
+## Overview
+
+There are many Authenticators and Spawners available for JupyterHub. Some, such
+as DockerSpawner or OAuthenticator, do not need any elevated permissions. This
+document describes how to get the full default behavior of JupyterHub while
+running notebook servers as real system users on a shared system without 
+running the Hub itself as root.
+
+Since JupyterHub needs to spawn processes as other users, the simplest way
+is to run it as root, spawning user servers with [setuid](http://linux.die.net/man/2/setuid).
+But this isn't especially safe, because you have a process running on the
+public web as root.
+
+A **more prudent way** to run the server while preserving functionality is to
+create a dedicated user with `sudo` access restricted to launching and
+monitoring single-user servers.
+
+## Create a user
+
+To do this, first create a user that will run the Hub:
+
+```bash
+sudo useradd rhea
+```
+
+This user shouldn't have a login shell or password (possible with -r).
+
+## Set up sudospawner
+
+Next, you will need [sudospawner](https://github.com/jupyter/sudospawner)
+to enable monitoring the single-user servers with sudo:
+
+```bash
+sudo pip install sudospawner
+```
+
+Now we have to configure sudo to allow the Hub user (`rhea`) to launch
+the sudospawner script on behalf of our hub users (here `zoe` and `wash`).
+We want to confine these permissions to only what we really need.
+
+## Edit `/etc/sudoers`
+
+To do this we add to `/etc/sudoers` (use `visudo` for safe editing of sudoers):
+
+- specify the list of users `JUPYTER_USERS` for whom `rhea` can spawn servers
+- set the command `JUPYTER_CMD` that `rhea` can execute on behalf of users
+- give `rhea` permission to run `JUPYTER_CMD` on behalf of `JUPYTER_USERS` 
+  without entering a password
+
+
+For example:
+
+```bash
+# comma-separated whitelist of users that can spawn single-user servers
+# this should include all of your Hub users
+Runas_Alias JUPYTER_USERS = rhea, zoe, wash
+
+# the command(s) the Hub can run on behalf of the above users without needing a password
+# the exact path may differ, depending on how sudospawner was installed
+Cmnd_Alias JUPYTER_CMD = /usr/local/bin/sudospawner
+
+# actually give the Hub user permission to run the above command on behalf
+# of the above users without prompting for a password
+rhea ALL=(JUPYTER_USERS) NOPASSWD:JUPYTER_CMD
+```
+
+It might be useful to modify `secure_path` to add commands in path.
+
+As an alternative to adding every user to the `/etc/sudoers` file, you can
+use a group in the last line above, instead of `JUPYTER_USERS`:
+
+```bash
+rhea ALL=(%jupyterhub) NOPASSWD:JUPYTER_CMD
+```
+
+If the `jupyterhub` group exists, there will be no need to edit `/etc/sudoers`
+again. A new user will gain access to the application when added to the group:
+
+```bash
+$ adduser -G jupyterhub newuser
+```
+
+## Test `sudo` setup
+
+Test that the new user doesn't need to enter a password to run the sudospawner
+command.
+
+This should prompt for your password to switch to rhea, but *not* prompt for
+any password for the second switch. It should show some help output about
+logging options:
+
+```bash
+$ sudo -u rhea sudo -n -u $USER /usr/local/bin/sudospawner --help
+Usage: /usr/local/bin/sudospawner [OPTIONS]
+    
+Options:
+    
+--help          show this help information
+...
+```
+
+And this should fail:
+
+```bash
+$ sudo -u rhea sudo -n -u $USER echo 'fail'
+sudo: a password is required
+```
+
+## Enable PAM for non-root
+
+By default, [PAM authentication](http://en.wikipedia.org/wiki/Pluggable_authentication_module)
+is used by JupyterHub. To use PAM, the process may need to be able to read
+the shadow password database.
+
+### Shadow group (Linux)
+
+```bash
+$ ls -l /etc/shadow
+-rw-r-----  1 root shadow   2197 Jul 21 13:41 shadow
+```
+
+If there's already a shadow group, you are set. If its permissions are more like:
+
+```bash
+    $ ls -l /etc/shadow
+    -rw-------  1 root wheel   2197 Jul 21 13:41 shadow
+```
+
+Then you may want to add a shadow group, and make the shadow file group-readable:
+
+```bash
+$ sudo groupadd shadow
+$ sudo chgrp shadow /etc/shadow
+$ sudo chmod g+r /etc/shadow
+```
+
+We want our new user to be able to read the shadow passwords, so add it to the shadow group:
+
+```bash
+    $ sudo usermod -a -G shadow rhea
+```
+
+If you want jupyterhub to serve pages on a restricted port (such as port 80 for http), 
+then you will need to give `node` permission to do so:
+
+```bash
+sudo setcap 'cap_net_bind_service=+ep' /usr/bin/node
+```
+However, you may want to further understand the consequences of this.
+
+You may also be interested in limiting the amount of CPU any process can use
+on your server. `cpulimit` is a useful tool that is available for many Linux
+distributions' packaging system. This can be used to keep any user's process
+from using too much CPU cycles. You can configure it accoring to [these
+instructions](http://ubuntuforums.org/showthread.php?t=992706).
+
+
+### Shadow group (FreeBSD)
+
+**NOTE:** This has not been tested and may not work as expected.
+
+```bash
+$ ls -l /etc/spwd.db /etc/master.passwd
+-rw-------  1 root  wheel   2516 Aug 22 13:35 /etc/master.passwd
+-rw-------  1 root  wheel  40960 Aug 22 13:35 /etc/spwd.db
+```
+
+Add a shadow group if there isn't one, and make the shadow file group-readable:
+
+```bash
+$ sudo pw group add shadow
+$ sudo chgrp shadow /etc/spwd.db
+$ sudo chmod g+r /etc/spwd.db
+$ sudo chgrp shadow /etc/master.passwd
+$ sudo chmod g+r /etc/master.passwd
+```
+
+We want our new user to be able to read the shadow passwords, so add it to the 
+shadow group:
+
+```bash
+$ sudo pw user mod rhea -G shadow
+```
+
+## Test that PAM works
+
+We can verify that PAM is working, with:
+
+```bash
+$ sudo -u rhea python3 -c "import pamela, getpass; print(pamela.authenticate('$USER', getpass.getpass()))"
+Password: [enter your unix password]
+```
+
+## Make a directory for JupyterHub
+
+JupyterHub stores its state in a database, so it needs write access to a directory.
+The simplest way to deal with this is to make a directory owned by your Hub user,
+and use that as the CWD when launching the server.
+
+```bash
+    $ sudo mkdir /etc/jupyterhub
+    $ sudo chown rhea /etc/jupyterhub
+```
+
+## Start jupyterhub
+
+Finally, start the server as our newly configured user, `rhea`:
+
+```bash
+    $ cd /etc/jupyterhub
+    $ sudo -u rhea jupyterhub --JupyterHub.spawner_class=sudospawner.SudoSpawner
+```
+
+And try logging in.
+
+### Troubleshooting: SELinux
+
+If you still get a generic `Permission denied` `PermissionError`, it's possible SELinux is blocking you.  
+Here's how you can make a module to allow this.
+First, put this in a file sudo_exec_selinux.te:
+
+```bash
+module sudo_exec 1.1;
+
+require {
+        type unconfined_t;
+        type sudo_exec_t;
+        class file { read entrypoint };
+}
+
+#============= unconfined_t ==============
+allow unconfined_t sudo_exec_t:file entrypoint;
+```
+
+Then run all of these commands as root:
+
+```bash
+$ checkmodule -M -m -o sudo_exec_selinux.mod sudo_exec_selinux.te
+$ semodule_package -o sudo_exec_selinux.pp -m sudo_exec_selinux.mod
+$ semodule -i sudo_exec_selinux.pp
+```
+
+### Troubleshooting: PAM session errors
+
+If the PAM authentication doesn't work and you see errors for
+`login:session-auth`, or similar, considering updating to `master` 
+and/or incorporating this commit https://github.com/jupyter/jupyterhub/commit/40368b8f555f04ffdd662ffe99d32392a088b1d2
+and configuration option, `c.PAMAuthenticator.open_sessions = False`.

docs/source/reference/config-user-env.md

@@ -0,0 +1,147 @@
+# Configuring user environments
+
+Deploying JupyterHub means you are providing Jupyter notebook environments for
+multiple users. Often, this includes a desire to configure the user
+environment in some way.
+
+Since the `jupyterhub-singleuser` server extends the standard Jupyter notebook
+server, most configuration and documentation that applies to Jupyter Notebook
+applies to the single-user environments. Configuration of user environments
+typically does not occur through JupyterHub itself, but rather through system-
+wide configuration of Jupyter, which is inherited by `jupyterhub-singleuser`.
+
+**Tip:** When searching for configuration tips for JupyterHub user
+environments, try removing JupyterHub from your search because there are a lot
+more people out there configuring Jupyter than JupyterHub and the
+configuration is the same.
+
+This section will focus on user environments, including:
+
+- Installing packages
+- Configuring Jupyter and IPython
+- Installing kernelspecs
+- Using containers vs. multi-user hosts
+
+
+## Installing packages
+
+To make packages available to users, you generally will install packages
+system-wide or in a shared environment.
+
+This installation location should always be in the same environment that
+`jupyterhub-singleuser` itself is installed in, and must be *readable and
+executable* by your users. If you want users to be able to install additional
+packages, it must also be *writable* by your users.
+
+If you are using a standard system Python install, you would use:
+
+
+```bash
+sudo python3 -m pip install numpy
+```
+
+to install the numpy package in the default system Python 3 environment
+(typically `/usr/local`).
+
+You may also use conda to install packages. If you do, you should make sure
+that the conda environment has appropriate permissions for users to be able to
+run Python code in the env.
+
+
+## Configuring Jupyter and IPython
+
+[Jupyter](https://jupyter-notebook.readthedocs.io/en/stable/config_overview.html)
+and [IPython](https://ipython.readthedocs.io/en/stable/development/config.html)
+have their own configuration systems.
+
+As a JupyterHub administrator, you will typically want to install and configure
+environments for all JupyterHub users. For example, you wish for each student in
+a class to have the same user environment configuration.
+
+Jupyter and IPython support **"system-wide"** locations for configuration, which
+is the logical place to put global configuration that you want to affect all
+users. It's generally more efficient to configure user environments "system-wide",
+and it's a good idea to avoid creating files in users' home directories.
+
+The typical locations for these config files are:
+- **system-wide** in `/etc/{jupyter|ipython}`
+- **env-wide** (environment wide) in `{sys.prefix}/etc/{jupyter|ipython}`.
+
+### Example: Enable an extension system-wide
+
+For example, to enable the `cython` IPython extension for all of your users,
+create the file `/etc/ipython/ipython_config.py`:
+
+```python
+c.InteractiveShellApp.extensions.append("cython")
+```
+
+### Example: Enable a Jupyter notebook configuration setting for all users
+
+To enable Jupyter notebook's internal idle-shutdown behavior (requires
+notebook ≥ 5.4), set the following in the `/etc/jupyter/jupyter_notebook_config.py`
+file:
+
+```python
+# shutdown the server after no activity for an hour
+c.NotebookApp.shutdown_no_activity_timeout = 60 * 60
+# shutdown kernels after no activity for 20 minutes
+c.MappingKernelManager.cull_idle_timeout = 20 * 60
+# check for idle kernels every two minutes
+c.MappingKernelManager.cull_interval = 2 * 60
+```
+
+
+## Installing kernelspecs
+
+You may have multiple Jupyter kernels installed and want to make sure that
+they are available to all of your users. This means installing kernelspecs
+either system-wide (e.g. in /usr/local/) or in the `sys.prefix` of JupyterHub
+itself.
+
+Jupyter kernelspec installation is system wide by default, but some kernels
+may default to installing kernelspecs in your home directory. These will need
+to be moved system-wide to ensure that they are accessible.
+
+You can see where your kernelspecs are with:
+
+```bash
+jupyter kernelspec list
+```
+
+### Example: Installing kernels system-wide
+
+Assuming I have a Python 2 and Python 3 environment that I want to make
+sure are available, I can install their specs system-wide (in /usr/local) with:
+
+```bash
+/path/to/python3 -m IPython kernel install --prefix=/usr/local
+/path/to/python2 -m IPython kernel install --prefix=/usr/local
+```
+
+
+## Multi-user hosts vs. Containers 
+
+There are two broad categories of user environments that depend on what
+Spawner you choose:
+
+- Multi-user hosts (shared system)
+- Container-based
+
+How you configure user environments for each category can differ a bit
+depending on what Spawner you are using.
+
+The first category is a **shared system (multi-user host)** where
+each user has a JupyterHub account and a home directory as well as being
+a real system user. In this example, shared configuration and installation
+must be in a 'system-wide' location, such as `/etc/` or `/usr/local`
+or a custom prefix such as `/opt/conda`.
+
+When JupyterHub uses **container-based** Spawners (e.g. KubeSpawner or
+DockerSpawner), the 'system-wide' environment is really the container image
+which you are using for users.
+
+In both cases, you want to *avoid putting configuration in user home
+directories* because users can change those configuration settings. Also,
+home directories typically persist once they are created, so they are
+difficult for admins to update later.

docs/source/reference/database.md

@@ -0,0 +1,62 @@
+# The Hub's Database
+
+JupyterHub uses a database to store information about users, services, and other
+data needed for operating the Hub.
+
+## Default SQLite database
+
+The default database for JupyterHub is a [SQLite](https://sqlite.org) database.
+We have chosen SQLite as JupyterHub's default for its lightweight simplicity
+in certain uses such as testing, small deployments and workshops.
+
+For production systems, SQLite has some disadvantages when used with JupyterHub:
+
+- `upgrade-db` may not work, and you may need to start with a fresh database
+- `downgrade-db` **will not** work if you want to rollback to an earlier
+  version, so backup the `jupyterhub.sqlite` file before upgrading
+
+The sqlite documentation provides a helpful page about [when to use SQLite and
+where traditional RDBMS may be a better choice](https://sqlite.org/whentouse.html).
+
+## Using an RDBMS (PostgreSQL, MySQL)
+
+When running a long term deployment or a production system, we recommend using
+a traditional RDBMS database, such as [PostgreSQL](https://www.postgresql.org)
+or [MySQL](https://www.mysql.com), that supports the SQL `ALTER TABLE`
+statement.
+
+## Notes and Tips
+
+### SQLite
+
+The SQLite database should not be used on NFS. SQLite uses reader/writer locks
+to control access to the database. This locking mechanism might not work
+correctly if the database file is kept on an NFS filesystem. This is because
+`fcntl()` file locking is broken on many NFS implementations. Therefore, you
+should avoid putting SQLite database files on NFS since it will not handle well
+multiple processes which might try to access the file at the same time.
+
+### PostgreSQL
+
+We recommend using PostgreSQL for production if you are unsure whether to use
+MySQL or PostgreSQL or if you do not have a strong preference. There is
+additional configuration required for MySQL that is not needed for PostgreSQL.
+
+### MySQL / MariaDB
+
+- You should use the `pymysql` sqlalchemy provider (the other one, MySQLdb,
+  isn't available for py3).
+- You also need to set `pool_recycle` to some value (typically 60 - 300) 
+  which depends on your  MySQL setup. This is necessary since MySQL kills
+  connections serverside if they've been idle for a while, and the connection
+  from the hub will be idle for longer than most connections. This behavior
+  will lead to frustrating 'the connection has gone away' errors from
+  sqlalchemy if `pool_recycle` is not set.
+- If you use `utf8mb4` collation with MySQL earlier than 5.7.7 or MariaDB
+  earlier than 10.2.1 you may get an `1709, Index column size too large` error.
+  To fix this you need to set `innodb_large_prefix` to enabled and
+  `innodb_file_format` to `Barracuda` to allow for the index sizes jupyterhub
+  uses. `row_format` will be set to `DYNAMIC` as long as those options are set
+  correctly. Later versions of MariaDB and MySQL should set these values by
+  default, as well as have a default `DYNAMIC` `row_format` and pose no trouble
+  to users.

docs/source/reference/index.rst

@@ -11,5 +11,11 @@ Technical Reference
    services
    proxy
    rest
+   database
    upgrading
+   templates
+   config-user-env
    config-examples
+   config-ghoauth
+   config-proxy
+   config-sudo

docs/source/reference/proxy.md

@@ -1,22 +1,26 @@
 # Writing a custom Proxy implementation
 
-JupyterHub 0.8 introduced the ability to write a custom implementation of the proxy.
+JupyterHub 0.8 introduced the ability to write a custom implementation of the
-This enables deployments with different needs than the default proxy,
+proxy. This enables deployments with different needs than the default proxy,
-configurable-http-proxy (CHP).
+configurable-http-proxy (CHP). CHP is a single-process nodejs proxy that the
-CHP is a single-process nodejs proxy that they Hub manages by default as a subprocess
+Hub manages by default as a subprocess (it can be run externally, as well, and
-(it can be run externally, as well, and typically is in production deployments).
+typically is in production deployments).
 
-The upside to CHP, and why we use it by default, is that it's easy to install and run (if you have nodejs, you are set!).
+The upside to CHP, and why we use it by default, is that it's easy to install
-The downsides are that it's a single process and does not support any persistence of the routing table.
+and run (if you have nodejs, you are set!). The downsides are that it's a
-So if the proxy process dies, your whole JupyterHub instance is inaccessible until the Hub notices, restarts the proxy, and restores the routing table.
+single process and does not support any persistence of the routing table. So
-For deployments that want to avoid such a single point of failure,
+if the proxy process dies, your whole JupyterHub instance is inaccessible
-or leverage existing proxy infrastructure in their chosen deployment (such as Kubernetes ingress objects),
+until the Hub notices, restarts the proxy, and restores the routing table. For
-the Proxy API provides a way to do that.
+deployments that want to avoid such a single point of failure, or leverage
+existing proxy infrastructure in their chosen deployment (such as Kubernetes
+ingress objects), the Proxy API provides a way to do that.
 
 In general, for a proxy to be usable by JupyterHub, it must:
 
-1. support websockets without prior knowledge of the URL where websockets may occur
+1. support websockets without prior knowledge of the URL where websockets may
-2. support trie-based routing (i.e. allow different routes on `/foo` and `/foo/bar` and route based on specificity)
+   occur
+2. support trie-based routing (i.e. allow different routes on `/foo` and 
+   `/foo/bar` and route based on specificity)
 3. adding or removing a route should not cause existing connections to drop
 
 Optionally, if the JupyterHub deployment is to use host-based routing,
@@ -35,10 +39,10 @@ class MyProxy(Proxy):
     ...
 ```
 
-
 ## Starting and stopping the proxy
 
-If your proxy should be launched when the Hub starts, you must define how to start and stop your proxy:
+If your proxy should be launched when the Hub starts, you must define how
+to start and stop your proxy:
 
 ```python
 from tornado import gen
@@ -55,8 +59,8 @@ class MyProxy(Proxy):
 
 These methods **may** be  coroutines.
 
-`c.Proxy.should_start` is a configurable flag that determines whether the Hub should call these methods when the Hub itself starts and stops.
+`c.Proxy.should_start` is a configurable flag that determines whether the
-
+Hub should call these methods when the Hub itself starts and stops.
 
 ### Purely external proxies
 
@@ -70,31 +74,30 @@ class MyProxy(Proxy):
     should_start = False
 ```
 
+## Routes
 
-## Adding and removing routes
+At its most basic, a Proxy implementation defines a mechanism to add, remove,
-
+and retrieve routes. A proxy that implements these three methods is complete.
-At its most basic, a Proxy implementation defines a mechanism to add, remove, and retrieve routes.
-A proxy that implements these three methods is complete.
 Each of these methods **may** be a coroutine.
 
 **Definition:** routespec
 
-A routespec, which will appear in these methods, is a string describing a route to be proxied,
+A routespec, which will appear in these methods, is a string describing a
-such as `/user/name/`. A routespec will:
+route to be proxied, such as `/user/name/`. A routespec will:
 
 1. always end with `/`
 2. always start with `/` if it is a path-based route `/proxy/path/`
-3. precede the leading `/` with a host for host-based routing, e.g. `host.tld/proxy/path/`
+3. precede the leading `/` with a host for host-based routing, e.g.
-
+   `host.tld/proxy/path/`
 
 ### Adding a route
 
-When adding a route, JupyterHub may pass a JSON-serializable dict as a `data` argument
+When adding a route, JupyterHub may pass a JSON-serializable dict as a `data`
-that should be attacked to the proxy route.
+argument that should be attacked to the proxy route. When that route is
-When that route is retrieved, the `data` argument should be returned as well.
+retrieved, the `data` argument should be returned as well. If your  proxy
-If your  proxy implementation doesn't support storing data attached to routes,
+implementation doesn't support storing data attached to routes, then your
-then your Python wrapper may have to handle storing the `data` piece itself,
+Python wrapper may have to handle storing the `data` piece itself, e.g in a
-e.g in a simple file or database.
+simple file or database.
 
 ```python
 @gen.coroutine
@@ -113,12 +116,10 @@ proxy.add_route('/user/pgeorgiou/', 'http://127.0.0.1:1227',
                 {'user': 'pgeorgiou'})
 ```
 
-
 ### Removing routes
 
-`delete_route()` is given a routespec to delete.
+`delete_route()` is given a routespec to delete. If there is no such route,
-If there is no such route, `delete_route` should still succeed,
+`delete_route` should still succeed, but a warning may be issued.
-but a warning may be issued.
 
 ```python
 @gen.coroutine
@@ -126,18 +127,17 @@ def delete_route(self, routespec):
     """Delete the route"""
 ```
 
-
 ### Retrieving routes
 
-For retrieval, you only *need* to implement a single method that retrieves all routes.
+For retrieval, you only *need* to implement a single method that retrieves all
-The return value for this function should be a dictionary, keyed by `routespect`,
+routes. The return value for this function should be a dictionary, keyed by
-of dicts whose keys are the same three arguments passed to `add_route`
+`routespect`, of dicts whose keys are the same three arguments passed to
-(`routespec`, `target`, `data`)
+`add_route` (`routespec`, `target`, `data`)
 
 ```python
 @gen.coroutine
 def get_all_routes(self):
-    """Return all routes, keyed by routespec""""
+    """Return all routes, keyed by routespec"""
 ```
 
 ```python
@@ -150,15 +150,15 @@ def get_all_routes(self):
 }
 ```
 
+## Note on activity tracking
 
-
+JupyterHub can track activity of users, for use in services such as culling
-#### Note on activity tracking
+idle servers. As of JupyterHub 0.8, this activity tracking is the
-
+responsibility of the proxy. If your proxy implementation can track activity
-JupyterHub can track activity of users, for use in services such as culling idle servers.
+to endpoints, it may add a `last_activity` key to the `data` of routes
-As of JupyterHub 0.8, this activity tracking is the responsibility of the proxy.
+retrieved in `.get_all_routes()`. If present, the value of `last_activity`
-If your proxy implementation can track activity to endpoints,
+should be an [ISO8601](https://en.wikipedia.org/wiki/ISO_8601) UTC date
-it may add a `last_activity` key to the `data` of routes retrieved in `.get_all_routes()`.
+string:
-If present, the value of `last_activity` should be an [ISO8601](https://en.wikipedia.org/wiki/ISO_8601) UTC date string:
 
 ```python
 {
@@ -173,11 +173,9 @@ If present, the value of `last_activity` should be an [ISO8601](https://en.wikip
 }
 ```
 
+If the proxy does not track activity, then only activity to the Hub itself is
+tracked, and services such as cull-idle will not work.
 
-If the proxy does not track activity, then only activity to the Hub itself is tracked,
+Now that `notebook-5.0` tracks activity internally, we can retrieve activity
-and services such as cull-idle will not work.
+information from the single-user servers instead, removing the need to track
-
+activity in the proxy. But this is not yet implemented in JupyterHub 0.8.0.
-Now that `notebook-5.0` tracks activity internally,
-we can retrieve activity information from the single-user servers instead,
-removing the need to track activity in the proxy.
-But this is not yet implemented in JupyterHub 0.8.0.

docs/source/reference/services.md

@@ -15,7 +15,7 @@ This section provides the following information about Services:
 ## Definition of a Service
 
 When working with JupyterHub, a **Service** is defined as a process that interacts
-with the Hub's REST API. A Service may perform a specific or
+with the Hub's REST API. A Service may perform a specific
 action or task. For example, the following tasks can each be a unique Service:
 
 - shutting down individuals' single user notebook servers that have been idle
@@ -205,9 +205,9 @@ To use HubAuth, you must set the `.api_token`, either programmatically when cons
 or via the `JUPYTERHUB_API_TOKEN` environment variable.
 
 Most of the logic for authentication implementation is found in the 
-[`HubAuth.user_for_cookie`](services.auth.html#jupyterhub.services.auth.HubAuth.user_for_cookie)
+[`HubAuth.user_for_cookie`][HubAuth.user_for_cookie] 
 and in the 
-[`HubAuth.user_for_token`](services.auth.html#jupyterhub.services.auth.HubAuth.user_for_token)
+[`HubAuth.user_for_token`][HubAuth.user_for_token]
 methods, which makes a request of the Hub, and returns:
 
 - None, if no user could be identified, or
@@ -359,14 +359,16 @@ and taking note of the following process:
    ```
 
 An example of using an Externally-Managed Service and authentication is
-in [nbviewer README]_ section on securing the notebook viewer,
+in [nbviewer README][nbviewer example] section on securing the notebook viewer,
 and an example of its configuration is found [here](https://github.com/jupyter/nbviewer/blob/master/nbviewer/providers/base.py#L94).
-nbviewer can also be run as a Hub-Managed Service as described [nbviewer README]_
+nbviewer can also be run as a Hub-Managed Service as described [nbviewer README][nbviewer example]
 section on securing the notebook viewer.
 
 
 [requests]: http://docs.python-requests.org/en/master/
 [services_auth]: ../api/services.auth.html
 [HubAuth]: ../api/services.auth.html#jupyterhub.services.auth.HubAuth
+[HubAuth.user_for_cookie]: ../api/services.auth.html#jupyterhub.services.auth.HubAuth.user_for_cookie
+[HubAuth.user_for_token]: ../api/services.auth.html#jupyterhub.services.auth.HubAuth.user_for_token
 [HubAuthenticated]: ../api/services.auth.html#jupyterhub.services.auth.HubAuthenticated
 [nbviewer example]: https://github.com/jupyter/nbviewer#securing-the-notebook-viewer

docs/source/reference/spawners.md

@@ -46,7 +46,16 @@ Most `Spawner.start` functions will look similar to this example:
 def start(self):
     self.ip = '127.0.0.1'
     self.port = random_port()
-    yield self._actually_start_server_somehow()
+    # get environment variables,
+    # several of which are required for configuring the single-user server
+    env = self.get_env()
+    cmd = []
+    # get jupyterhub command to run,
+    # typically ['jupyterhub-singleuser']
+    cmd.extend(self.cmd)
+    cmd.extend(self.get_args())
+
+    yield self._actually_start_server_somehow(cmd, env)
     return (self.ip, self.port)
 ```
 
@@ -170,9 +179,12 @@ If you are interested in building a custom spawner, you can read [this tutorial]
 Some spawners of the single-user notebook servers allow setting limits or
 guarantees on resources, such as CPU and memory. To provide a consistent
 experience for sysadmins and users, we provide a standard way to set and
-discover these resource limits and guarantees, such as for memory and CPU. For
+discover these resource limits and guarantees, such as for memory and CPU.
-the limits and guarantees to be useful, the spawner must implement support for
+For the limits and guarantees to be useful, **the spawner must implement
-them.
+support for them**. For example, LocalProcessSpawner, the default
+spawner, does not support limits and guarantees. One of the spawners
+that supports limits and guarantees is the `systemdspawner`.
+
 
 ### Memory Limits & Guarantees
 
@@ -184,14 +196,14 @@ allocate. Attempting to use more memory than this limit will cause errors. The
 single-user notebook server can discover its own memory limit by looking at
 the environment variable `MEM_LIMIT`, which is specified in absolute bytes.
 
-`c.Spawner.mem_guarantee`: Sometimes, a **guarantee** of a *minumum amount of
+`c.Spawner.mem_guarantee`: Sometimes, a **guarantee** of a *minimum amount of
 memory* is desirable. In this case, you can set `c.Spawner.mem_guarantee` to
 to provide a guarantee that at minimum this much memory will always be
 available for the single-user notebook server to use. The environment variable
 `MEM_GUARANTEE` will also be set in the single-user notebook server.
 
-The spawner's underlying system or cluster is responsible for enforcing these
+**The spawner's underlying system or cluster is responsible for enforcing these
-limits and providing these guarantees. If these values are set to `None`, no
+limits and providing these guarantees.** If these values are set to `None`, no
 limits or guarantees are provided, and no environment values are set.
 
 ### CPU Limits & Guarantees
@@ -208,6 +220,6 @@ higher priority applications might be taking up CPU.
 guarantee for CPU usage. The environment variable `CPU_GUARANTEE` will be set
 in the single-user notebook server when a guarantee is being provided.
 
-The spawner's underlying system or cluster is responsible for enforcing these
+**The spawner's underlying system or cluster is responsible for enforcing these
-limits and providing these guarantees. If these values are set to `None`, no
+limits and providing these guarantees.** If these values are set to `None`, no
 limits or guarantees are provided, and no environment values are set.

docs/source/reference/templates.md

@@ -0,0 +1,93 @@
+# Working with templates and UI
+
+The pages of the JupyterHub application are generated from
+[Jinja](http://jinja.pocoo.org/) templates.  These allow the header, for
+example, to be defined once and incorporated into all pages.  By providing
+your own templates, you can have complete control over JupyterHub's
+appearance.
+
+## Custom Templates
+
+JupyterHub will look for custom templates in all of the paths in the
+`JupyterHub.template_paths` configuration option, falling back on the
+[default templates](https://github.com/jupyterhub/jupyterhub/tree/master/share/jupyterhub/templates)
+if no custom template with that name is found. This fallback
+behavior is new in version 0.9; previous versions searched only those paths
+explicitly included in `template_paths`. You may override as many
+or as few templates as you desire.
+
+## Extending Templates
+
+Jinja provides a mechanism to [extend templates](http://jinja.pocoo.org/docs/2.10/templates/#template-inheritance).
+A base template can define a `block`, and child templates can replace or
+supplement the material in the block.  The 
+[JupyterHub templates](https://github.com/jupyterhub/jupyterhub/tree/master/share/jupyterhub/templates)
+make extensive use of blocks, which allows you to customize parts of the
+interface easily.
+
+In general, a child template can extend a base template, `base.html`, by beginning with:
+
+```html
+{% extends "base.html" %}
+```
+
+This works, unless you are trying to extend the default template for the same
+file name.  Starting in version 0.9, you may refer to the base file with a
+`templates/` prefix.  Thus, if you are writing a custom `base.html`, start the
+file with this block:
+
+```html
+{% extends "templates/base.html" %}
+```
+
+By defining `block`s with same name as in the base template, child templates
+can replace those sections with custom content.  The content from the base
+template can be included with the `{{ super() }}` directive.
+
+### Example
+
+To add an additional message to the spawn-pending page, below the existing
+text about the server starting up, place this content in a file named
+`spawn_pending.html` in a directory included in the
+`JupyterHub.template_paths` configuration option.
+
+```html
+{% extends "templates/spawn_pending.html" %}
+
+{% block message %}
+{{ super() }}
+<p>Patience is a virtue.</p>
+{% endblock %}
+```
+
+## Page Announcements
+
+To add announcements to be displayed on a page, you have two options:
+
+- Extend the page templates as described above
+- Use configuration variables
+
+### Announcement Configuration Variables
+
+If you set the configuration variable `JupyterHub.template_vars =
+{'announcement': 'some_text}`, the given `some_text` will be placed on
+the top of all pages.  The more specific variables
+`announcement_login`, `announcement_spawn`, `announcement_home`, and
+`announcement_logout` are more specific and only show on their
+respective pages (overriding the global `announcement` variable).
+Note that changing these variables require a restart, unlike direct
+template extension.
+
+You can get the same effect by extending templates, which allows you
+to update the messages without restarting.  Set
+`c.JupyterHub.template_paths` as mentioned above, and then create a
+template (for example, `login.html`) with:
+
+```html
+{% extends "templates/login.html" %}
+{% set announcement = 'some message' %}
+```
+
+Extending `page.html` puts the message on all pages, but note that
+extending `page.html` take precedence over an extension of a specific
+page (unlike the variable-based approach above).

docs/source/reference/upgrading.md

@@ -2,30 +2,22 @@
 
 From time to time, you may wish to upgrade JupyterHub to take advantage
 of new releases. Much of this process is automated using scripts,
-such as those generated by alembic for database upgrades. Before upgrading a
+such as those generated by alembic for database upgrades. Whether you
-JupyterHub deployment, it's critical to backup your data and configurations
+are using the default SQLite database or an RDBMS, such as PostgreSQL or
-before shutting down the JupyterHub process and server.
+MySQL, the process follows similar steps.
 
-## Databases: SQLite (default) or RDBMS (PostgreSQL, MySQL)
+**Before upgrading a JupyterHub deployment**, it's critical to backup your data
+and configurations before shutting down the JupyterHub process and server.
 
-The default database for JupyterHub is a [SQLite](https://sqlite.org) database.
+## Note about upgrading the SQLite database
-We have chosen SQLite as JupyterHub's default for its lightweight simplicity
-in certain uses such as testing, small deployments and workshops.
 
-When running a long term deployment or a production system, we recommend using
+When used in production systems, SQLite has some disadvantages when it
-a traditional RDBMS database, such as [PostgreSQL](https://www.postgresql.org)
+comes to upgrading JupyterHub. These are:
-or [MySQL](https://www.mysql.com), that supports the SQL `ALTER TABLE`
-statement.
-
-For production systems, SQLite has some disadvantages when used with JupyterHub:
 
 - `upgrade-db` may not work, and you may need to start with a fresh database
 - `downgrade-db` **will not** work if you want to rollback to an earlier
   version, so backup the `jupyterhub.sqlite` file before upgrading
 
-The sqlite documentation provides a helpful page about [when to use sqlite and
-where traditional RDBMS may be a better choice](https://sqlite.org/whentouse.html).
-
 ## The upgrade process
 
 Five fundamental process steps are needed when upgrading JupyterHub and its

docs/source/spelling_wordlist.txt

@@ -166,7 +166,7 @@ startup
 statsd
 stdin
 stdout
-stoppped
+stopped
 subclasses
 subcommand
 subdomain

docs/source/troubleshooting.md

@@ -9,6 +9,7 @@ problem and how to resolve it.
 - sudospawner fails to run
 - What is the default behavior when none of the lists (admin, whitelist,
   group whitelist) are set?
+- JupyterHub Docker container not accessible at localhost
 
 [*Errors*](#errors)
 - 500 error after spawning my single-user server
@@ -63,6 +64,17 @@ this to a particular set of users, and the admin_users lets you specify who
 among them may use the admin interface (not necessary, unless you need to do
 things like inspect other users' servers, or modify the userlist at runtime).
 
+### JupyterHub Docker container not accessible at localhost
+
+Even though the command to start your Docker container exposes port 8000 
+(`docker run -p 8000:8000 -d --name jupyterhub jupyterhub/jupyterhub jupyterhub`), 
+it is possible that the IP address itself is not accessible/visible. As a result 
+when you try http://localhost:8000 in your browser, you are unable to connect 
+even though the container is running properly. One workaround is to explicitly 
+tell Jupyterhub to start at `0.0.0.0` which is visible to everyone. Try this 
+command: 
+`docker run -p 8000:8000 -d --name jupyterhub jupyterhub/jupyterhub jupyterhub --ip 0.0.0.0 --port 8000`
+
 
 ## Errors
 
@@ -89,7 +101,7 @@ check if the cookie corresponds to the right user. This request is logged.
 If everything is working, the response logged will be similar to this:
 
 ```
-200 GET /hub/api/authorizations/cookie/jupyter-hub-token-name/[secret] (@10.0.1.4) 6.10ms
+200 GET /hub/api/authorizations/cookie/jupyterhub-token-name/[secret] (@10.0.1.4) 6.10ms
 ```
 
 You should see a similar 200 message, as above, in the Hub log when you first
@@ -99,7 +111,7 @@ may mean that your single-user notebook server isn't connecting to your Hub.
 If you see 403 (forbidden) like this, it's a token problem:
 
 ```
-403 GET /hub/api/authorizations/cookie/jupyter-hub-token-name/[secret] (@10.0.1.4) 4.14ms
+403 GET /hub/api/authorizations/cookie/jupyterhub-token-name/[secret] (@10.0.1.4) 4.14ms
 ```
 
 Check the logs of the single-user notebook server, which may have more detailed

docs/source/tutorials/upgrade-dot-eight.rst

@@ -1,4 +1,4 @@
-.. upgrade-dot-eight:
+.. _upgrade-dot-eight:
 
 Upgrading to JupyterHub version 0.8
 ===================================

docs/sphinxext/autodoc_traits.py

@@ -7,14 +7,18 @@ from sphinx.ext.autodoc import ClassDocumenter, AttributeDocumenter
 
 class ConfigurableDocumenter(ClassDocumenter):
     """Specialized Documenter subclass for traits with config=True"""
+
     objtype = 'configurable'
     directivetype = 'class'
 
     def get_object_members(self, want_all):
         """Add traits with .tag(config=True) to members list"""
         check, members = super().get_object_members(want_all)
-        get_traits = self.object.class_own_traits if self.options.inherited_members \
+        get_traits = (
-                     else self.object.class_traits
+            self.object.class_own_traits
+            if self.options.inherited_members
+            else self.object.class_traits
+        )
         trait_members = []
         for name, trait in sorted(get_traits(config=True).items()):
             # put help in __doc__ where autodoc will look for it
@@ -42,10 +46,7 @@ class TraitDocumenter(AttributeDocumenter):
             default_s = ''
         else:
             default_s = repr(default)
-        sig = ' = {}({})'.format(
+        sig = ' = {}({})'.format(self.object.__class__.__name__, default_s)
-            self.object.__class__.__name__,
-            default_s,
-        )
         return super().add_directive_header(sig)
 
 

examples/bootstrap-script/README.md

@@ -25,6 +25,9 @@ Another use would be to copy initial content, such as tutorial files or referenc
 You can define your own bootstrap process by implementing a `pre_spawn_hook` on any spawner.
 The Spawner itself is passed as parameter to your hook and you can easily get the contextual information out of the spawning process. 
 
+Similarly, there may be cases where you would like to clean up after a spawner stops.
+You may implement a `post_stop_hook` that is always executed after the spawner stops.
+
 If you implement a hook, make sure that it is *idempotent*. It will be executed every time
 a notebook server is spawned to the user. That means you should somehow
 ensure that things which should run only once are not running again and again.

examples/bootstrap-script/jupyterhub_config.py

@@ -1,8 +1,14 @@
-# Example for a Spawner.pre_spawn_hook
+"""
-# create a directory for the user before the spawner starts
+Example for a Spawner.pre_spawn_hook
-
+create a directory for the user before the spawner starts
+"""
+# pylint: disable=import-error
 import os
+import shutil
+from jupyter_client.localinterfaces import public_ips
+
 def create_dir_hook(spawner):
+    """ Create directory """
     username = spawner.user.name # get the username
     volume_path = os.path.join('/volumes/jupyterhub', username)
     if not os.path.exists(volume_path):
@@ -10,17 +16,25 @@ def create_dir_hook(spawner):
         # now do whatever you think your user needs
         # ...
 
-# attach the hook function to the spawner
+def clean_dir_hook(spawner):
+    """ Delete directory """
+    username = spawner.user.name # get the username
+    temp_path = os.path.join('/volumes/jupyterhub', username, 'temp')
+    if os.path.exists(temp_path) and os.path.isdir(temp_path):
+        shutil.rmtree(temp_path)
+
+# attach the hook functions to the spawner
+# pylint: disable=undefined-variable
 c.Spawner.pre_spawn_hook = create_dir_hook
+c.Spawner.post_stop_hook = clean_dir_hook
 
 # Use the DockerSpawner to serve your users' notebooks
 c.JupyterHub.spawner_class = 'dockerspawner.DockerSpawner'
-from jupyter_client.localinterfaces import public_ips
 c.JupyterHub.hub_ip = public_ips()[0]
 c.DockerSpawner.hub_ip_connect = public_ips()[0]
 c.DockerSpawner.container_ip = "0.0.0.0"
 
 # You can now mount the volume to the docker container as we've
 # made sure the directory exists
+# pylint: disable=bad-whitespace
 c.DockerSpawner.volumes = { '/volumes/jupyterhub/{username}/': '/home/jovyan/work' }
-

examples/cull-idle/README.md

@@ -15,7 +15,7 @@ c.JupyterHub.services = [
     {
         'name': 'cull-idle',
         'admin': True,
-        'command': 'python cull_idle_servers.py --timeout=3600'.split(),
+        'command': 'python3 cull_idle_servers.py --timeout=3600'.split(),
     }
 ]
 ```
@@ -37,5 +37,5 @@ variable. Run `cull_idle_servers.py` manually.
 
 ```bash
     export JUPYTERHUB_API_TOKEN=`jupyterhub token`
-    python cull_idle_servers.py [--timeout=900] [--url=http://127.0.0.1:8081/hub/api]
+    python3 cull_idle_servers.py [--timeout=900] [--url=http://127.0.0.1:8081/hub/api]
 ```

examples/cull-idle/cull_idle_servers.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 """script to monitor and cull idle single-user servers
 
 Caveats:
@@ -16,102 +16,348 @@ You can run this as a service managed by JupyterHub with this in your config::
         {
             'name': 'cull-idle',
             'admin': True,
-            'command': 'python cull_idle_servers.py --timeout=3600'.split(),
+            'command': 'python3 cull_idle_servers.py --timeout=3600'.split(),
         }
     ]
 
 Or run it manually by generating an API token and storing it in `JUPYTERHUB_API_TOKEN`:
 
     export JUPYTERHUB_API_TOKEN=`jupyterhub token`
-    python cull_idle_servers.py [--timeout=900] [--url=http://127.0.0.1:8081/hub/api]
+    python3 cull_idle_servers.py [--timeout=900] [--url=http://127.0.0.1:8081/hub/api]
+
+This script uses the same ``--timeout`` and ``--max-age`` values for
+culling users and users' servers.  If you want a different value for
+users and servers, you should add this script to the services list
+twice, just with different ``name``s, different values, and one with
+the ``--cull-users`` option.
 """
 
-import datetime
+from datetime import datetime, timezone
+from functools import partial
 import json
 import os
 
-from dateutil.parser import parse as parse_date
+try:
+    from urllib.parse import quote
+except ImportError:
+    from urllib import quote
 
-from tornado.gen import coroutine
+import dateutil.parser
+
+from tornado.gen import coroutine, multi
+from tornado.locks import Semaphore
 from tornado.log import app_log
 from tornado.httpclient import AsyncHTTPClient, HTTPRequest
 from tornado.ioloop import IOLoop, PeriodicCallback
 from tornado.options import define, options, parse_command_line
 
 
+def parse_date(date_string):
+    """Parse a timestamp
+
+    If it doesn't have a timezone, assume utc
+
+    Returned datetime object will always be timezone-aware
+    """
+    dt = dateutil.parser.parse(date_string)
+    if not dt.tzinfo:
+        # assume naïve timestamps are UTC
+        dt = dt.replace(tzinfo=timezone.utc)
+    return dt
+
+
+def format_td(td):
+    """
+    Nicely format a timedelta object
+
+    as HH:MM:SS
+    """
+    if td is None:
+        return "unknown"
+    if isinstance(td, str):
+        return td
+    seconds = int(td.total_seconds())
+    h = seconds // 3600
+    seconds = seconds % 3600
+    m = seconds // 60
+    seconds = seconds % 60
+    return "{h:02}:{m:02}:{seconds:02}".format(h=h, m=m, seconds=seconds)
+
+
 @coroutine
-def cull_idle(url, api_token, timeout, cull_users=False):
+def cull_idle(url, api_token, inactive_limit, cull_users=False, max_age=0, concurrency=10):
     """Shutdown idle single-user servers
 
     If cull_users, inactive *users* will be deleted as well.
     """
     auth_header = {
-            'Authorization': 'token %s' % api_token
+        'Authorization': 'token %s' % api_token,
-        }
+    }
-    req = HTTPRequest(url=url + '/users',
+    req = HTTPRequest(
+        url=url + '/users',
         headers=auth_header,
     )
-    now = datetime.datetime.utcnow()
+    now = datetime.now(timezone.utc)
-    cull_limit = now - datetime.timedelta(seconds=timeout)
     client = AsyncHTTPClient()
-    resp = yield client.fetch(req)
+
+    if concurrency:
+        semaphore = Semaphore(concurrency)
+        @coroutine
+        def fetch(req):
+            """client.fetch wrapped in a semaphore to limit concurrency"""
+            yield semaphore.acquire()
+            try:
+                return (yield client.fetch(req))
+            finally:
+                yield semaphore.release()
+    else:
+        fetch = client.fetch
+
+    resp = yield fetch(req)
     users = json.loads(resp.body.decode('utf8', 'replace'))
     futures = []
 
     @coroutine
-    def cull_one(user, last_activity):
+    def handle_server(user, server_name, server):
-        """cull one user"""
+        """Handle (maybe) culling a single server
 
-        # shutdown server first. Hub doesn't allow deleting users with running servers.
+        Returns True if server is now stopped (user removable),
-        if user['server']:
+        False otherwise.
-            app_log.info("Culling server for %s (inactive since %s)", user['name'], last_activity)
+        """
-            req = HTTPRequest(url=url + '/users/%s/server' % user['name'],
+        log_name = user['name']
-                method='DELETE',
+        if server_name:
-                headers=auth_header,
+            log_name = '%s/%s' % (user['name'], server_name)
+        if server.get('pending'):
+            app_log.warning(
+                "Not culling server %s with pending %s",
+                log_name, server['pending'])
+            return False
+
+        # jupyterhub < 0.9 defined 'server.url' once the server was ready
+        # as an *implicit* signal that the server was ready.
+        # 0.9 adds a dedicated, explicit 'ready' field.
+        # By current (0.9) definitions, servers that have no pending
+        # events and are not ready shouldn't be in the model,
+        # but let's check just to be safe.
+
+        if not server.get('ready', bool(server['url'])):
+            app_log.warning(
+                "Not culling not-ready not-pending server %s: %s",
+                log_name, server)
+            return False
+
+        if server.get('started'):
+            age = now - parse_date(server['started'])
+        else:
+            # started may be undefined on jupyterhub < 0.9
+            age = None
+
+        # check last activity
+        # last_activity can be None in 0.9
+        if server['last_activity']:
+            inactive = now - parse_date(server['last_activity'])
+        else:
+            # no activity yet, use start date
+            # last_activity may be None with jupyterhub 0.9,
+            # which introduces the 'started' field which is never None
+            # for running servers
+            inactive = age
+
+        should_cull = (inactive is not None and
+                       inactive.total_seconds() >= inactive_limit)
+        if should_cull:
+            app_log.info(
+                "Culling server %s (inactive for %s)",
+                log_name, format_td(inactive))
+
+        if max_age and not should_cull:
+            # only check started if max_age is specified
+            # so that we can still be compatible with jupyterhub 0.8
+            # which doesn't define the 'started' field
+            if age is not None and age.total_seconds() >= max_age:
+                app_log.info(
+                    "Culling server %s (age: %s, inactive for %s)",
+                    log_name, format_td(age), format_td(inactive))
+                should_cull = True
+
+        if not should_cull:
+            app_log.debug(
+                "Not culling server %s (age: %s, inactive for %s)",
+                log_name, format_td(age), format_td(inactive))
+            return False
+
+        if server_name:
+            # culling a named server
+            delete_url = url + "/users/%s/servers/%s" % (
+                quote(user['name']), quote(server['name'])
             )
-            yield client.fetch(req)
+        else:
-        if cull_users:
+            delete_url = url + '/users/%s/server' % quote(user['name'])
-            app_log.info("Culling user %s (inactive since %s)", user['name'], last_activity)
+
-            req = HTTPRequest(url=url + '/users/%s' % user['name'],
+        req = HTTPRequest(
-                method='DELETE',
+            url=delete_url, method='DELETE', headers=auth_header,
-                headers=auth_header,
+        )
+        resp = yield fetch(req)
+        if resp.code == 202:
+            app_log.warning(
+                "Server %s is slow to stop",
+                log_name,
             )
-            yield client.fetch(req)
+            # return False to prevent culling user with pending shutdowns
+            return False
+        return True
+
+    @coroutine
+    def handle_user(user):
+        """Handle one user.
+
+        Create a list of their servers, and async exec them.  Wait for
+        that to be done, and if all servers are stopped, possibly cull
+        the user.
+        """
+        # shutdown servers first.
+        # Hub doesn't allow deleting users with running servers.
+        # jupyterhub 0.9 always provides a 'servers' model.
+        # 0.8 only does this when named servers are enabled.
+        if 'servers' in user:
+            servers = user['servers']
+        else:
+            # jupyterhub < 0.9 without named servers enabled.
+            # create servers dict with one entry for the default server
+            # from the user model.
+            # only if the server is running.
+            servers = {}
+            if user['server']:
+                servers[''] = {
+                    'last_activity': user['last_activity'],
+                    'pending': user['pending'],
+                    'url': user['server'],
+                }
+        server_futures = [
+            handle_server(user, server_name, server)
+            for server_name, server in servers.items()
+        ]
+        results = yield multi(server_futures)
+        if not cull_users:
+            return
+        # some servers are still running, cannot cull users
+        still_alive = len(results) - sum(results)
+        if still_alive:
+            app_log.debug(
+                "Not culling user %s with %i servers still alive",
+                user['name'], still_alive)
+            return False
+
+        should_cull = False
+        if user.get('created'):
+            age = now - parse_date(user['created'])
+        else:
+            # created may be undefined on jupyterhub < 0.9
+            age = None
+
+        # check last activity
+        # last_activity can be None in 0.9
+        if user['last_activity']:
+            inactive = now - parse_date(user['last_activity'])
+        else:
+            # no activity yet, use start date
+            # last_activity may be None with jupyterhub 0.9,
+            # which introduces the 'created' field which is never None
+            inactive = age
+
+        should_cull = (inactive is not None and
+                       inactive.total_seconds() >= inactive_limit)
+        if should_cull:
+            app_log.info(
+                "Culling user %s (inactive for %s)",
+                user['name'], inactive)
+
+        if max_age and not should_cull:
+            # only check created if max_age is specified
+            # so that we can still be compatible with jupyterhub 0.8
+            # which doesn't define the 'started' field
+            if age is not None and age.total_seconds() >= max_age:
+                app_log.info(
+                    "Culling user %s (age: %s, inactive for %s)",
+                    user['name'], format_td(age), format_td(inactive))
+                should_cull = True
+
+        if not should_cull:
+            app_log.debug(
+                "Not culling user %s (created: %s, last active: %s)",
+                user['name'], format_td(age), format_td(inactive))
+            return False
+
+        req = HTTPRequest(
+            url=url + '/users/%s' % user['name'],
+            method='DELETE',
+            headers=auth_header,
+        )
+        yield fetch(req)
+        return True
 
     for user in users:
-        if not user['server'] and not cull_users:
+        futures.append((user['name'], handle_user(user)))
-            # server not running and not culling users, nothing to do
-            continue
-        last_activity = parse_date(user['last_activity'])
-        if last_activity < cull_limit:
-            futures.append((user['name'], cull_one(user, last_activity)))
-        else:
-            app_log.debug("Not culling %s (active since %s)", user['name'], last_activity)
 
     for (name, f) in futures:
-        yield f
+        try:
-        app_log.debug("Finished culling %s", name)
+            result = yield f
+        except Exception:
+            app_log.exception("Error processing %s", name)
+        else:
+            if result:
+                app_log.debug("Finished culling %s", name)
 
 
 if __name__ == '__main__':
-    define('url', default=os.environ.get('JUPYTERHUB_API_URL'), help="The JupyterHub API URL")
+    define(
-    define('timeout', default=600, help="The idle timeout (in seconds)")
+        'url',
-    define('cull_every', default=0, help="The interval (in seconds) for checking for idle servers to cull")
+        default=os.environ.get('JUPYTERHUB_API_URL'),
-    define('cull_users', default=False,
+        help="The JupyterHub API URL",
-        help="""Cull users in addition to servers.
-                This is for use in temporary-user cases such as tmpnb.""",
     )
+    define('timeout', default=600, help="The idle timeout (in seconds)")
+    define('cull_every', default=0,
+           help="The interval (in seconds) for checking for idle servers to cull")
+    define('max_age', default=0,
+           help="The maximum age (in seconds) of servers that should be culled even if they are active")
+    define('cull_users', default=False,
+           help="""Cull users in addition to servers.
+                This is for use in temporary-user cases such as tmpnb.""",
+           )
+    define('concurrency', default=10,
+           help="""Limit the number of concurrent requests made to the Hub.
+
+                Deleting a lot of users at the same time can slow down the Hub,
+                so limit the number of API requests we have outstanding at any given time.
+                """
+           )
 
     parse_command_line()
     if not options.cull_every:
         options.cull_every = options.timeout // 2
-    
     api_token = os.environ['JUPYTERHUB_API_TOKEN']
 
+    try:
+        AsyncHTTPClient.configure("tornado.curl_httpclient.CurlAsyncHTTPClient")
+    except ImportError as e:
+        app_log.warning(
+            "Could not load pycurl: %s\n"
+            "pycurl is recommended if you have a large number of users.",
+            e)
+
     loop = IOLoop.current()
-    cull = lambda : cull_idle(options.url, api_token, options.timeout, options.cull_users)
+    cull = partial(
-    # run once before scheduling periodic call
+        cull_idle,
-    loop.run_sync(cull)
+        url=options.url,
+        api_token=api_token,
+        inactive_limit=options.timeout,
+        cull_users=options.cull_users,
+        max_age=options.max_age,
+        concurrency=options.concurrency,
+    )
+    # schedule first cull immediately
+    # because PeriodicCallback doesn't start until the end of the first interval
+    loop.add_callback(cull)
     # schedule periodic cull
     pc = PeriodicCallback(cull, 1e3 * options.cull_every)
     pc.start()
@@ -119,4 +365,3 @@ if __name__ == '__main__':
         loop.start()
     except KeyboardInterrupt:
         pass
-    

examples/cull-idle/jupyterhub_config.py

@@ -3,6 +3,6 @@ c.JupyterHub.services = [
     {
         'name': 'cull-idle',
         'admin': True,
-        'command': 'python cull_idle_servers.py --timeout=3600'.split(),
+        'command': 'python3 cull_idle_servers.py --timeout=3600'.split(),
     }
 ]

examples/external-oauth/README.md

@@ -0,0 +1,90 @@
+# Using JupyterHub as an OAuth provider
+
+JupyterHub 0.9 introduces the ability to use JupyterHub as an OAuth provider
+for external services that may not be otherwise integrated with JupyterHub.
+The main feature this enables is using JupyterHub like a 'regular' OAuth 2
+provider for services running anywhere.
+
+There are two examples here. `whoami-oauth` (in the service-whoami directory) uses `jupyterhub.services.HubOAuthenticated`
+to authenticate requests with the Hub for a service run on its own host.
+This is an implementation of OAuth 2.0 provided by the jupyterhub package,
+which configures all of the necessary URLs from environment variables.
+
+The second is `whoami-oauth-basic`, which implements the full OAuth process
+without any inheritance, so it can be used as a reference for OAuth
+implementations in other web servers or languages.
+
+## Run the example
+
+1. generate an API token:
+
+        export JUPYTERHUB_API_TOKEN=`openssl rand -hex 32`
+
+2. launch a version of the the whoami service.
+   For `whoami-oauth`:
+
+        bash launch-service.sh &
+
+    or for `whoami-oauth-basic`:
+
+        bash launch-service-basic.sh &
+
+3. Launch JupyterHub:
+
+        jupyterhub
+
+4. Visit http://127.0.0.1:5555/
+
+After logging in with your local-system credentials, you should see a JSON dump of your user info:
+
+```json
+{
+ "admin": false,
+ "last_activity": "2016-05-27T14:05:18.016372",
+ "name": "queequeg",
+ "pending": null,
+ "server": "/user/queequeg"
+}
+```
+
+
+The essential pieces for using JupyterHub as an OAuth provider are:
+
+1. registering your service with jupyterhub:
+
+    ```python
+    c.JupyterHub.services = [
+        {
+            # the name of your service
+            # should be simple and unique.
+            # mostly used to identify your service in logging
+            "name": "my-service",
+            # the oauth client id of your service
+            # must be unique but isn't private
+            # can be randomly generated or hand-written
+            "oauth_client_id": "abc123",
+            # the API token and client secret of the service
+            # should be generated securely,
+            # e.g. via `openssl rand -hex 32`
+            "api_token": "abc123...",
+            # the redirect target for jupyterhub to send users
+            # after successful authentication
+            "oauth_redirect_uri": "https://service-host/oauth_callback"
+        }
+    ]
+    ```
+
+2. Telling your service how to authenticate with JupyterHub.
+
+The relevant OAuth URLs and keys for using JupyterHub as an OAuth provider are:
+
+1. the client_id, used in oauth requests
+2. the api token registered with jupyterhub is the client_secret for oauth requests
+3. oauth url of the Hub, which is "/hub/api/oauth2/authorize", e.g. `https://myhub.horse/hub/api/oauth2/authorize`
+4. a redirect handler to receive the authenticated response
+   (at `oauth_redirect_uri` registered in jupyterhub config)
+5. the token URL for completing the oauth process is "/hub/api/oauth2/token",
+   e.g. `https://myhub.horse/hub/api/oauth2/token`.
+   The reply is JSON and the token is in the field `access_token`.
+6. Users can be identified by oauth token by making a request to `/hub/api/user`
+   with the new token in the `Authorization` header.

examples/external-oauth/jupyterhub_config.py

@@ -0,0 +1,18 @@
+import os
+
+# get the oauth client's API token.
+# this could come from anywhere
+api_token = os.getenv("JUPYTERHUB_API_TOKEN")
+if not api_token:
+    raise ValueError("Make sure to `export JUPYTERHUB_API_TOKEN=$(openssl rand -hex 32)`")
+
+# tell JupyterHub to register the service as an external oauth client
+
+c.JupyterHub.services = [
+    {
+        'name': 'external-oauth',
+        'oauth_client_id': "whoami-oauth-client-test",
+        'api_token': api_token,
+        'oauth_redirect_uri': 'http://127.0.0.1:5555/oauth_callback',
+    },
+]

examples/external-oauth/launch-service-basic.sh

@@ -0,0 +1,20 @@
+#!/usr/bin/env bash
+# script to launch whoami-oauth-basic service
+set -euo pipefail
+
+# the service needs to know:
+# 1. API token
+if [[ -z "${JUPYTERHUB_API_TOKEN}" ]]; then
+    echo 'set API token with export JUPYTERHUB_API_TOKEN=$(openssl rand -hex 32)'
+fi
+
+# 2. oauth client ID
+export JUPYTERHUB_CLIENT_ID='whoami-oauth-client-test'
+# 3. where the Hub is
+export JUPYTERHUB_URL='http://127.0.0.1:8000'
+
+# 4. where to run
+export JUPYTERHUB_SERVICE_URL='http://127.0.0.1:5555'
+
+# launch the service
+exec python3 whoami-oauth-basic.py

examples/external-oauth/launch-service.sh

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+# script to launch whoami-oauth service
+set -euo pipefail
+
+# the service needs to know:
+# 1. API token
+if [[ -z "${JUPYTERHUB_API_TOKEN}" ]]; then
+    echo 'set API token with export JUPYTERHUB_API_TOKEN=$(openssl rand -hex 32)'
+fi
+
+# 2. oauth client ID
+export JUPYTERHUB_CLIENT_ID="whoami-oauth-client-test"
+# 3. what URL to run on
+export JUPYTERHUB_SERVICE_PREFIX='/'
+export JUPYTERHUB_SERVICE_URL='http://127.0.0.1:5555'
+export JUPYTERHUB_OAUTH_CALLBACK_URL="$JUPYTERHUB_SERVICE_URL/oauth_callback"
+# 4. where the Hub is
+export JUPYTERHUB_HOST='http://127.0.0.1:8000'
+
+# launch the service
+exec python3 ../service-whoami/whoami-oauth.py

examples/external-oauth/whoami-oauth-basic.py

@@ -0,0 +1,135 @@
+"""Basic implementation of OAuth without any inheritance
+
+Implements OAuth handshake manually
+so all URLs and requests necessary for OAuth with JupyterHub should be in one place
+"""
+
+import json
+import os
+import sys
+from urllib.parse import urlencode, urlparse
+
+from tornado.auth import OAuth2Mixin
+from tornado.httpclient import AsyncHTTPClient, HTTPRequest
+from tornado.httputil import url_concat
+from tornado.ioloop import IOLoop
+from tornado import log
+from tornado import web
+
+
+class JupyterHubLoginHandler(web.RequestHandler):
+    """Login Handler
+
+    this handler both begins and ends the OAuth process
+    """
+
+    async def token_for_code(self, code):
+        """Complete OAuth by requesting an access token for an oauth code"""
+        params = dict(
+            client_id=self.settings['client_id'],
+            client_secret=self.settings['api_token'],
+            grant_type='authorization_code',
+            code=code,
+            redirect_uri=self.settings['redirect_uri'],
+        )
+        req = HTTPRequest(self.settings['token_url'], method='POST',
+                          body=urlencode(params).encode('utf8'),
+                          headers={
+            'Content-Type': 'application/x-www-form-urlencoded',
+        },
+        )
+        response = await AsyncHTTPClient().fetch(req)
+        data = json.loads(response.body.decode('utf8', 'replace'))
+        return data['access_token']
+
+    async def get(self):
+        code = self.get_argument('code', None)
+        if code:
+            # code is set, we are the oauth callback
+            # complete oauth
+            token = await self.token_for_code(code)
+            # login successful, set cookie and redirect back to home
+            self.set_secure_cookie('whoami-oauth-token', token)
+            self.redirect('/')
+        else:
+            # we are the login handler,
+            # begin oauth process which will come back later with an
+            # authorization_code
+            self.redirect(url_concat(
+                self.settings['authorize_url'],
+                dict(
+                    redirect_uri=self.settings['redirect_uri'],
+                    client_id=self.settings['client_id'],
+                    response_type='code',
+                )
+            ))
+
+
+class WhoAmIHandler(web.RequestHandler):
+    """Serve the JSON model for the authenticated user"""
+
+    def get_current_user(self):
+        """The login handler stored a JupyterHub API token in a cookie
+
+        @web.authenticated calls this method.
+        If a Falsy value is returned, the request is redirected to `login_url`.
+        If a Truthy value is returned, the request is allowed to proceed.
+        """
+        token = self.get_secure_cookie('whoami-oauth-token')
+
+        if token:
+            # secure cookies are bytes, decode to str
+            return token.decode('ascii', 'replace')
+
+    async def user_for_token(self, token):
+        """Retrieve the user for a given token, via /hub/api/user"""
+
+        req = HTTPRequest(
+            self.settings['user_url'],
+            headers={
+                'Authorization': f'token {token}'
+            },
+        )
+        response = await AsyncHTTPClient().fetch(req)
+        return json.loads(response.body.decode('utf8', 'replace'))
+
+    @web.authenticated
+    async def get(self):
+        user_token = self.get_current_user()
+        user_model = await self.user_for_token(user_token)
+        self.set_header('content-type', 'application/json')
+        self.write(json.dumps(user_model, indent=1, sort_keys=True))
+
+
+def main():
+    log.enable_pretty_logging()
+
+    # construct OAuth URLs from jupyterhub base URL
+    hub_api = os.environ['JUPYTERHUB_URL'].rstrip('/') + '/hub/api'
+    authorize_url = hub_api + '/oauth2/authorize'
+    token_url = hub_api + '/oauth2/token'
+    user_url = hub_api + '/user'
+
+    app = web.Application([
+        ('/oauth_callback', JupyterHubLoginHandler),
+        ('/', WhoAmIHandler),
+    ],
+        login_url='/oauth_callback',
+        cookie_secret=os.urandom(32),
+        api_token=os.environ['JUPYTERHUB_API_TOKEN'],
+        client_id=os.environ['JUPYTERHUB_CLIENT_ID'],
+        redirect_uri=os.environ['JUPYTERHUB_SERVICE_URL'].rstrip('/') + '/oauth_callback',
+        authorize_url=authorize_url,
+        token_url=token_url,
+        user_url=user_url,
+    )
+
+    url = urlparse(os.environ['JUPYTERHUB_SERVICE_URL'])
+    log.app_log.info("Running basic whoami service on %s",
+                     os.environ['JUPYTERHUB_SERVICE_URL'])
+    app.listen(url.port, url.hostname)
+    IOLoop.current().start()
+
+
+if __name__ == '__main__':
+    main()

examples/service-announcement/README.md

@@ -0,0 +1,60 @@
+
+# Simple Announcement Service Example
+
+This is a simple service that allows administrators to manage announcements
+that appear when JupyterHub renders pages.
+
+To run the service as a hub-managed service simply include in your JupyterHub
+configuration file something like:
+
+    c.JupyterHub.services = [
+            {
+                'name': 'announcement',
+                'url': 'http://127.0.0.1:8888',
+                'command': ["python", "-m", "announcement"],
+            }
+    ]
+
+This starts the announcements service up at `/services/announcement` when
+JupyterHub launches.  By default the announcement text is empty.
+
+The `announcement` module has a configurable port (default 8888) and an API
+prefix setting.  By default the API prefix is `JUPYTERHUB_SERVICE_PREFIX` if
+that environment variable is set or `/` if it is not.
+
+## Managing the Announcement
+
+Admin users can set the announcement text with an API token:
+
+    $ curl -X POST -H "Authorization: token <token>"                        \
+        -d "{'announcement':'JupyterHub will be upgraded on August 14!'}"   \
+        https://.../services/announcement
+
+Anyone can read the announcement:
+
+    $ curl https://.../services/announcement | python -m json.tool
+    {
+        announcement: "JupyterHub will be upgraded on August 14!",
+        timestamp: "...",
+        user: "..."
+    }
+
+The time the announcement was posted is recorded in the `timestamp` field and
+the user who posted the announcement is recorded in the `user` field.
+
+To clear the announcement text, just DELETE.  Only admin users can do this.
+
+    $ curl -X POST -H "Authorization: token <token>"                        \
+        https://.../services/announcement
+
+## Seeing the Announcement in JupyterHub
+
+To be able to render the announcement, include the provide `page.html` template
+that extends the base `page.html` template.  Set `c.JupyterHub.template_paths`
+in JupyterHub's configuration to include the path to the extending template.
+The template changes the `announcement` element and does a JQuery `$.get()` call
+to retrieve the announcement text.
+
+JupyterHub's configurable announcement template variables can be set for various
+pages like login, logout, spawn, and home.  Including the template provided in
+this example overrides all of those.

examples/service-announcement/announcement.py

@@ -0,0 +1,73 @@
+
+import argparse
+import datetime
+import json
+import os
+
+from jupyterhub.services.auth import HubAuthenticated
+from tornado import escape, gen, ioloop, web
+
+
+class AnnouncementRequestHandler(HubAuthenticated, web.RequestHandler):
+    """Dynamically manage page announcements"""
+
+    hub_users = []
+    allow_admin = True
+
+    def initialize(self, storage):
+        """Create storage for announcement text"""
+        self.storage = storage
+
+    @web.authenticated
+    def post(self):
+        """Update announcement"""
+        doc = escape.json_decode(self.request.body)
+        self.storage["announcement"] = doc["announcement"]
+        self.storage["timestamp"] = datetime.datetime.now().isoformat()
+        self.storage["user"] = user["name"]
+        self.write_to_json(self.storage)
+
+    def get(self):
+        """Retrieve announcement"""
+        self.write_to_json(self.storage)
+
+    @web.authenticated
+    def delete(self):
+        """Clear announcement"""
+        self.storage["announcement"] = ""
+        self.write_to_json(self.storage)
+
+    def write_to_json(self, doc):
+        """Write dictionary document as JSON"""
+        self.set_header("Content-Type", "application/json; charset=UTF-8")
+        self.write(escape.utf8(json.dumps(doc)))
+
+
+def main():
+    args = parse_arguments()
+    application = create_application(**vars(args))
+    application.listen(args.port)
+    ioloop.IOLoop.current().start()
+
+
+def parse_arguments():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--api-prefix", "-a",
+            default=os.environ.get("JUPYTERHUB_SERVICE_PREFIX", "/"),
+            help="application API prefix")
+    parser.add_argument("--port", "-p",
+            default=8888,
+            help="port for API to listen on",
+            type=int)
+    return parser.parse_args()
+
+
+def create_application(api_prefix="/", 
+        handler=AnnouncementRequestHandler,
+        **kwargs):
+    storage = dict(announcement="", timestamp="", user="")
+    return web.Application([(api_prefix, handler, dict(storage=storage))])
+
+
+if __name__ == "__main__":
+    main()

examples/service-announcement/jupyterhub_config.py

@@ -0,0 +1,15 @@
+
+# To run the announcement service managed by the hub, add this.
+
+c.JupyterHub.services = [
+        {
+            'name': 'announcement',
+            'url': 'http://127.0.0.1:8888',
+            'command': ["python", "-m", "announcement"],
+        }
+]
+
+# The announcements need to get on the templates somehow, see page.html
+# for an example of how to do this.
+
+c.JupyterHub.template_paths = ["templates"]

examples/service-announcement/templates/page.html

@@ -0,0 +1,14 @@
+{% extends "templates/page.html" %}
+{% block announcement %}
+<div class="container text-center announcement">
+</div>
+{% endblock %}
+
+{% block script %}
+{{ super() }}
+<script>
+$.get("/services/announcement/", function(data) {
+    $(".announcement").html(data["announcement"]);
+});
+</script>
+{% endblock %}

examples/service-whoami/README.md

@@ -26,6 +26,10 @@ After logging in with your local-system credentials, you should see a JSON dump
 
 This relies on the Hub starting the whoami services, via config (see [jupyterhub_config.py](./jupyterhub_config.py)).
 
+You may set the `hub_users` configuration in the service script
+to restrict access to the service to a whitelist of allowed users.
+By default, any authenticated user is allowed.
+
 A similar service could be run externally, by setting the JupyterHub service environment variables:
 
     JUPYTERHUB_API_TOKEN

examples/service-whoami/whoami-oauth.py

@@ -17,7 +17,11 @@ from jupyterhub.services.auth import HubOAuthenticated, HubOAuthCallbackHandler
 from jupyterhub.utils import url_path_join
 
 class WhoAmIHandler(HubOAuthenticated, RequestHandler):
-    hub_users = {getuser()} # the users allowed to access this service
+    # hub_users can be a set of users who are allowed to access the service
+    # `getuser()` here would mean only the user who started the service
+    # can access the service:
+
+    # hub_users = {getuser()}
 
     @authenticated
     def get(self):

examples/service-whoami/whoami.py

@@ -15,7 +15,11 @@ from jupyterhub.services.auth import HubAuthenticated
 
 
 class WhoAmIHandler(HubAuthenticated, RequestHandler):
-    hub_users = {getuser()} # the users allowed to access me
+    # hub_users can be a set of users who are allowed to access the service
+    # `getuser()` here would mean only the user who started the service
+    # can access the service:
+
+    # hub_users = {getuser()}
 
     @authenticated
     def get(self):

hooks/README.md

@@ -0,0 +1,3 @@
+# Docker Cloud build hooks
+
+These are the hooks

hooks/post_build

@@ -0,0 +1,4 @@
+#!/bin/bash
+set -exuo pipefail
+
+docker build --build-arg BASE_IMAGE=$DOCKER_REPO:$DOCKER_TAG -t ${DOCKER_REPO}-onbuild:$DOCKER_TAG onbuild

hooks/post_push

@@ -0,0 +1,33 @@
+#!/bin/bash
+set -exuo pipefail
+
+export ONBUILD=${DOCKER_REPO}-onbuild
+# push ONBUILD image
+docker push $ONBUILD:$DOCKER_TAG
+
+function get_hub_version() {
+  rm -f hub_version
+  docker run --rm -v $PWD:/version -u $(id -u) -i $DOCKER_REPO:$DOCKER_TAG sh -c 'jupyterhub --version > /version/hub_version'
+  hub_xyz=$(cat hub_version)
+  split=( ${hub_xyz//./ } )
+  hub_xy="${split[0]}.${split[1]}"
+  # add .dev on hub_xy so it's 1.0.dev
+  if [[ ! -z "${split[3]}" ]]; then
+    hub_xy="${hub_xy}.${split[3]}"
+  fi
+}
+
+
+get_hub_version
+
+# when building master, push 0.9.0.dev as well
+docker tag $DOCKER_REPO:$DOCKER_TAG $DOCKER_REPO:$hub_xyz
+docker push $DOCKER_REPO:$hub_xyz
+docker tag $ONBUILD:$DOCKER_TAG $ONBUILD:$hub_xyz
+docker push $ONBUILD:$hub_xyz
+
+# when building 0.9.x, push 0.9 as well
+docker tag $DOCKER_REPO:$DOCKER_TAG $DOCKER_REPO:$hub_xy
+docker push $DOCKER_REPO:$hub_xy
+docker tag $ONBUILD:$DOCKER_TAG $ONBUILD:$hub_xy
+docker push $ONBUILD:$hub_xyz

jupyterhub/_data.py

@@ -2,7 +2,7 @@
 
 
 def get_data_files():
-    """Walk up until we find share/jupyter/hub"""
+    """Walk up until we find share/jupyterhub"""
     import sys
     from os.path import join, abspath, dirname, exists, split
     path = abspath(dirname(__file__))
@@ -12,10 +12,10 @@ def get_data_files():
     for path in starting_points:
         # walk up, looking for prefix/share/jupyter
         while path != '/':
-            share_jupyter = join(path, 'share', 'jupyter', 'hub')
+            share_jupyterhub = join(path, 'share', 'jupyterhub')
-            static = join(share_jupyter, 'static')
+            static = join(share_jupyterhub, 'static')
             if all(exists(join(static, f)) for f in ['components', 'css']):
-                return share_jupyter
+                return share_jupyterhub
             path, _ = split(path)
     # didn't find it, give up
     return ''

jupyterhub/_version.py

@@ -5,12 +5,19 @@
 
 version_info = (
     0,
-    8,
+    9,
-    1,
+    4,
-    # 'dev',
+    "",  # release (b1, rc1, or "" for final or dev)
+    # "dev",  # dev or nothing
 )
 
-__version__ = '.'.join(map(str, version_info))
+# pep 440 version: no dot before beta/rc, but before .dev
+# 0.1.0rc1
+# 0.1.0a1
+# 0.1.0b1.dev
+# 0.1.0.dev
+
+__version__ = ".".join(map(str, version_info[:3])) + ".".join(version_info[3:])
 
 
 def _check_version(hub_version, singleuser_version, log):

jupyterhub/alembic/env.py

@@ -30,11 +30,9 @@ if 'jupyterhub' in sys.modules:
 else:
     fileConfig(config.config_file_name)
 
-# add your model's MetaData object here
+# add your model's MetaData object here for 'autogenerate' support
-# for 'autogenerate' support
+from jupyterhub import orm
-# from myapp import mymodel
+target_metadata = orm.Base.metadata
-# target_metadata = mymodel.Base.metadata
-target_metadata = None
 
 # other values from the config, defined by the needs of env.py,
 # can be acquired:

jupyterhub/alembic/versions/1cebaf56856c_session_id.py

@@ -0,0 +1,42 @@
+"""Add session_id to auth tokens
+
+Revision ID: 1cebaf56856c
+Revises: 3ec6993fe20c
+Create Date: 2017-12-07 14:43:51.500740
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '1cebaf56856c'
+down_revision = '3ec6993fe20c'
+branch_labels = None
+depends_on = None
+
+import logging
+logger = logging.getLogger('alembic')
+
+from alembic import op
+import sqlalchemy as sa
+
+tables = ('oauth_access_tokens', 'oauth_codes')
+
+
+def add_column_if_table_exists(table, column):
+    engine = op.get_bind().engine
+    if table not in engine.table_names():
+        # table doesn't exist, no need to upgrade
+        # because jupyterhub will create it on launch
+        logger.warning("Skipping upgrade of absent table: %s", table)
+        return
+    op.add_column(table, column)
+
+
+def upgrade():
+    for table in tables:
+        add_column_if_table_exists(table, sa.Column('session_id', sa.Unicode(255)))
+
+
+def downgrade():
+    # sqlite cannot downgrade because of limited ALTER TABLE support (no DROP COLUMN)
+    for table in tables:
+        op.drop_column(table, 'session_id')

jupyterhub/alembic/versions/56cc5a70207e_token_tracking.py

@@ -0,0 +1,44 @@
+"""token tracking
+
+Revision ID: 56cc5a70207e
+Revises: 1cebaf56856c
+Create Date: 2017-12-19 15:21:09.300513
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '56cc5a70207e'
+down_revision = '1cebaf56856c'
+branch_labels = None
+depends_on = None
+
+from alembic import op
+import sqlalchemy as sa
+
+import logging
+logger = logging.getLogger('alembic')
+
+
+def upgrade():
+    tables = op.get_bind().engine.table_names()
+    op.add_column('api_tokens', sa.Column('created', sa.DateTime(), nullable=True))
+    op.add_column('api_tokens', sa.Column('last_activity', sa.DateTime(), nullable=True))
+    op.add_column('api_tokens', sa.Column('note', sa.Unicode(length=1023), nullable=True))
+    if 'oauth_access_tokens' in tables:
+        op.add_column('oauth_access_tokens', sa.Column('created', sa.DateTime(), nullable=True))
+        op.add_column('oauth_access_tokens', sa.Column('last_activity', sa.DateTime(), nullable=True))
+        if op.get_context().dialect.name == 'sqlite':
+            logger.warning("sqlite cannot use ALTER TABLE to create foreign keys. Upgrade will be incomplete.")
+        else:
+            op.create_foreign_key(None, 'oauth_access_tokens', 'oauth_clients', ['client_id'], ['identifier'], ondelete='CASCADE')
+            op.create_foreign_key(None, 'oauth_codes', 'oauth_clients', ['client_id'], ['identifier'], ondelete='CASCADE')
+
+
+def downgrade():
+    op.drop_constraint(None, 'oauth_codes', type_='foreignkey')
+    op.drop_constraint(None, 'oauth_access_tokens', type_='foreignkey')
+    op.drop_column('oauth_access_tokens', 'last_activity')
+    op.drop_column('oauth_access_tokens', 'created')
+    op.drop_column('api_tokens', 'note')
+    op.drop_column('api_tokens', 'last_activity')
+    op.drop_column('api_tokens', 'created')

jupyterhub/alembic/versions/896818069c98_token_expires.py

@@ -0,0 +1,24 @@
+"""Add APIToken.expires_at
+
+Revision ID: 896818069c98
+Revises: d68c98b66cd4
+Create Date: 2018-05-07 11:35:58.050542
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '896818069c98'
+down_revision = 'd68c98b66cd4'
+branch_labels = None
+depends_on = None
+
+from alembic import op
+import sqlalchemy as sa
+
+
+def upgrade():
+    op.add_column('api_tokens', sa.Column('expires_at', sa.DateTime(), nullable=True))
+
+
+def downgrade():
+    op.drop_column('api_tokens', 'expires_at')

jupyterhub/alembic/versions/99a28a4418e1_user_created.py

@@ -0,0 +1,47 @@
+"""user.created and spawner.started
+
+Revision ID: 99a28a4418e1
+Revises: 56cc5a70207e
+Create Date: 2018-03-21 14:27:17.466841
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '99a28a4418e1'
+down_revision = '56cc5a70207e'
+branch_labels = None
+depends_on = None
+
+
+from alembic import op
+import sqlalchemy as sa
+
+from datetime import datetime
+
+def upgrade():
+    op.add_column('users', sa.Column('created', sa.DateTime, nullable=True))
+    c = op.get_bind()
+    # fill created date with current time
+    now = datetime.utcnow()
+    c.execute("""
+        UPDATE users
+        SET created='%s'
+        """ % (now,)
+    )
+
+    tables = c.engine.table_names()
+
+    if 'spawners' in tables:
+        op.add_column('spawners', sa.Column('started', sa.DateTime, nullable=True))
+        # fill started value with now for running servers
+        c.execute("""
+            UPDATE spawners
+            SET started='%s'
+            WHERE server_id IS NOT NULL
+            """ % (now,)
+        )
+
+
+def downgrade():
+    op.drop_column('users', 'created')
+    op.drop_column('spawners', 'started')

jupyterhub/alembic/versions/d68c98b66cd4_client_description.py

@@ -0,0 +1,29 @@
+"""client-description
+
+Revision ID: d68c98b66cd4
+Revises: 99a28a4418e1
+Create Date: 2018-04-13 10:50:17.968636
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = 'd68c98b66cd4'
+down_revision = '99a28a4418e1'
+branch_labels = None
+depends_on = None
+
+from alembic import op
+import sqlalchemy as sa
+
+
+def upgrade():
+    tables = op.get_bind().engine.table_names()
+    if 'oauth_clients' in tables:
+        op.add_column(
+            'oauth_clients',
+            sa.Column('description', sa.Unicode(length=1023))
+        )
+
+
+def downgrade():
+    op.drop_column('oauth_clients', 'description')

jupyterhub/apihandlers/auth.py

@@ -3,13 +3,15 @@
 # Copyright (c) Jupyter Development Team.
 # Distributed under the terms of the Modified BSD License.
 
+from datetime import datetime
 import json
 from urllib.parse import quote
 
 from oauth2.web.tornado import OAuth2Handler
-from tornado import web, gen
+from tornado import web
 
 from .. import orm
+from ..user import User
 from ..utils import token_authenticated
 from .base import BaseHandler, APIHandler
 
@@ -22,7 +24,11 @@ class TokenAPIHandler(APIHandler):
             orm_token = orm.OAuthAccessToken.find(self.db, token)
         if orm_token is None:
             raise web.HTTPError(404)
+
+        # record activity whenever we see a token
+        now = orm_token.last_activity = datetime.utcnow()
         if orm_token.user:
+            orm_token.user.last_activity = now
             model = self.user_model(self.users[orm_token.user])
         elif orm_token.service:
             model = self.service_model(orm_token.service)
@@ -31,17 +37,22 @@ class TokenAPIHandler(APIHandler):
             self.db.delete(orm_token)
             self.db.commit()
             raise web.HTTPError(404)
+        self.db.commit()
         self.write(json.dumps(model))
 
-    @gen.coroutine
+    async def post(self):
-    def post(self):
+        warn_msg = (
-        user = self.get_current_user()
+            "Using deprecated token creation endpoint %s."
+            " Use /hub/api/users/:user/tokens instead."
+        ) % self.request.uri
+        self.log.warning(warn_msg)
+        requester = user = self.get_current_user()
         if user is None:
             # allow requesting a token with username and password
             # for authenticators where that's possible
             data = self.get_json_body()
             try:
-                user = yield self.login_user(data)
+                requester = user = await self.login_user(data)
             except Exception as e:
                 self.log.error("Failure trying to authenticate with form data: %s" % e)
                 user = None
@@ -49,17 +60,25 @@ class TokenAPIHandler(APIHandler):
                 raise web.HTTPError(403)
         else:
             data = self.get_json_body()
-            # admin users can request 
+            # admin users can request tokens for other users
-            if data and data.get('username') != user.name:
+            if data and data.get('username'):
-                if user.admin:
+                user = self.find_user(data['username'])
-                    user = self.find_user(data['username'])
+                if user is not requester and not requester.admin:
-                    if user is None:
-                        raise web.HTTPError(400, "No such user '%s'" % data['username'])
-                else:
                     raise web.HTTPError(403, "Only admins can request tokens for other users.")
-        api_token = user.new_api_token()
+                if requester.admin and user is None:
+                    raise web.HTTPError(400, "No such user '%s'" % data['username'])
+
+        note = (data or {}).get('note')
+        if not note:
+            note = "Requested via deprecated api"
+            if requester is not user:
+                kind = 'user' if isinstance(user, User) else 'service'
+                note += " by %s %s" % (kind, requester.name)
+
+        api_token = user.new_api_token(note=note)
         self.write(json.dumps({
             'token': api_token,
+            'warning': warn_msg,
             'user': self.user_model(user),
         }))
 

jupyterhub/apihandlers/base.py

@@ -2,24 +2,36 @@
 # Copyright (c) Jupyter Development Team.
 # Distributed under the terms of the Modified BSD License.
 
+from datetime import datetime
 import json
 
 from http.client import responses
 
+from sqlalchemy.exc import SQLAlchemyError
 from tornado import web
 
+from .. import orm
 from ..handlers import BaseHandler
-from ..utils import url_path_join
+from ..utils import isoformat, url_path_join
+
 
 class APIHandler(BaseHandler):
+    """Base class for API endpoints
+
+    Differences from page handlers:
+
+    - JSON responses and errors
+    - strict referer checking for Cookie-authenticated requests
+    - strict content-security-policy
+    - methods for REST API models
+    """
 
     @property
     def content_security_policy(self):
         return '; '.join([super().content_security_policy, "default-src 'none'"])
 
-    def set_default_headers(self):
+    def get_content_type(self):
-        self.set_header('Content-Type', 'application/json')
+        return 'application/json'
-        super().set_default_headers()
 
     def check_referer(self):
         """Check Origin for cross-site API requests.
@@ -75,6 +87,7 @@ class APIHandler(BaseHandler):
         """Write JSON errors instead of HTML"""
         exc_info = kwargs.get('exc_info')
         message = ''
+        exception = None
         status_message = responses.get(status_code, 'Unknown Error')
         if exc_info:
             exception = exc_info[1]
@@ -88,13 +101,85 @@ class APIHandler(BaseHandler):
             reason = getattr(exception, 'reason', '')
             if reason:
                 status_message = reason
+
+        if exception and isinstance(exception, SQLAlchemyError):
+            self.log.warning("Rolling back session due to database error %s", exception)
+            self.db.rollback()
+
+        self.set_header('Content-Type', 'application/json')
+        if isinstance(exception, web.HTTPError):
+            # allow setting headers from exceptions
+            # since exception handler clears headers
+            headers = getattr(exception, 'headers', None)
+            if headers:
+                for key, value in headers.items():
+                    self.set_header(key, value)
+            # Content-Length must be recalculated.
+            self.clear_header('Content-Length')
+
         self.write(json.dumps({
             'status': status_code,
             'message': message or status_message,
         }))
 
-    def user_model(self, user):
+    def server_model(self, spawner, include_state=False):
+        """Get the JSON model for a Spawner"""
+        return {
+            'name': spawner.name,
+            'last_activity': isoformat(spawner.orm_spawner.last_activity),
+            'started': isoformat(spawner.orm_spawner.started),
+            'pending': spawner.pending,
+            'ready': spawner.ready,
+            'state': spawner.get_state() if include_state else None,
+            'url': url_path_join(spawner.user.url, spawner.name, '/'),
+            'progress_url': spawner._progress_url,
+        }
+
+    def token_model(self, token):
+        """Get the JSON model for an APIToken"""
+        expires_at = None
+        if isinstance(token, orm.APIToken):
+            kind = 'api_token'
+            extra = {
+                'note': token.note,
+            }
+            expires_at = token.expires_at
+        elif isinstance(token, orm.OAuthAccessToken):
+            kind = 'oauth'
+            extra = {
+                'oauth_client': token.client.description or token.client.client_id,
+            }
+            if token.expires_at:
+                expires_at = datetime.fromtimestamp(token.expires_at)
+        else:
+            raise TypeError(
+                "token must be an APIToken or OAuthAccessToken, not %s"
+                % type(token))
+
+        if token.user:
+            owner_key = 'user'
+            owner = token.user.name
+
+        else:
+            owner_key = 'service'
+            owner = token.service.name
+
+        model = {
+            owner_key: owner,
+            'id': token.api_id,
+            'kind': kind,
+            'created': isoformat(token.created),
+            'last_activity': isoformat(token.last_activity),
+            'expires_at': isoformat(expires_at),
+        }
+        model.update(extra)
+        return model
+
+    def user_model(self, user, include_servers=False, include_state=False):
         """Get the JSON model for a User object"""
+        if isinstance(user, orm.User):
+            user = self.users[user.id]
+
         model = {
             'kind': 'user',
             'name': user.name,
@@ -102,19 +187,22 @@ class APIHandler(BaseHandler):
             'groups': [ g.name for g in user.groups ],
             'server': user.url if user.running else None,
             'pending': None,
-            'last_activity': user.last_activity.isoformat(),
+            'created': isoformat(user.created),
+            'last_activity': isoformat(user.last_activity),
         }
-        model['pending'] = user.spawners[''].pending or None
+        if '' in user.spawners:
+            model['pending'] = user.spawners[''].pending
 
-        if self.allow_named_servers:
+        if not include_servers:
-            servers = model['servers'] = {}
+            model['servers'] = None
-            for name, spawner in user.spawners.items():
+            return model
-                if spawner.ready:
+
-                    servers[name] = s = {'name': name}
+        servers = model['servers'] = {}
-                    if spawner.pending:
+        for name, spawner in user.spawners.items():
-                        s['pending'] = spawner.pending
+            # include 'active' servers, not just ready
-                    if spawner.server:
+            # (this includes pending events)
-                        s['url'] = url_path_join(user.url, name, '/')
+            if spawner.active:
+                servers[name] = self.server_model(spawner, include_state=include_state)
         return model
 
     def group_model(self, group):
@@ -137,6 +225,7 @@ class APIHandler(BaseHandler):
         'name': str,
         'admin': bool,
         'groups': list,
+        'auth_state': dict,
     }
 
     _group_model_types = {
@@ -178,5 +267,14 @@ class APIHandler(BaseHandler):
 
 
     def options(self, *args, **kwargs):
-        self.set_header('Access-Control-Allow-Headers', 'accept, content-type')
         self.finish()
+
+
+class API404(APIHandler):
+    """404 for API requests
+
+    Ensures JSON 404 errors for malformed URLs
+    """
+    async def prepare(self):
+        await super().prepare()
+        raise web.HTTPError(404)

jupyterhub/apihandlers/groups.py

@@ -41,6 +41,37 @@ class GroupListAPIHandler(_GroupAPIHandler):
         data = [ self.group_model(g) for g in self.db.query(orm.Group) ]
         self.write(json.dumps(data))
 
+    @admin_only
+    async def post(self):
+        """POST creates Multiple groups """
+        model = self.get_json_body()
+        if not model or not isinstance(model, dict) or not model.get('groups'):
+            raise web.HTTPError(400, "Must specify at least one group to create")
+
+        groupnames = model.pop("groups",[])
+        self._check_group_model(model)
+
+        created = []
+        for name in groupnames:
+            existing = orm.Group.find(self.db, name=name)
+            if existing is not None:
+                raise web.HTTPError(409, "Group %s already exists" % name)
+
+            usernames = model.get('users', [])
+            # check that users exist
+            users = self._usernames_to_users(usernames)
+            # create the group
+            self.log.info("Creating new group %s with %i users",
+                name, len(users),
+            )
+            self.log.debug("Users: %s", usernames)
+            group = orm.Group(name=name, users=users)
+            self.db.add(group)
+            self.db.commit()
+            created.append(group)
+        self.write(json.dumps([self.group_model(group) for group in created]))
+        self.set_status(201)
+
 
 class GroupAPIHandler(_GroupAPIHandler):
     """View and modify groups by name"""
@@ -51,8 +82,7 @@ class GroupAPIHandler(_GroupAPIHandler):
         self.write(json.dumps(self.group_model(group)))
 
     @admin_only
-    @gen.coroutine
+    async def post(self, name):
-    def post(self, name):
         """POST creates a group by name"""
         model = self.get_json_body()
         if model is None:
@@ -62,7 +92,7 @@ class GroupAPIHandler(_GroupAPIHandler):
 
         existing = orm.Group.find(self.db, name=name)
         if existing is not None:
-            raise web.HTTPError(400, "Group %s already exists" % name)
+            raise web.HTTPError(409, "Group %s already exists" % name)
 
         usernames = model.get('users', [])
         # check that users exist
@@ -109,9 +139,8 @@ class GroupUsersAPIHandler(_GroupAPIHandler):
         self.db.commit()
         self.write(json.dumps(self.group_model(group)))
 
-    @gen.coroutine
     @admin_only
-    def delete(self, name):
+    async def delete(self, name):
         """DELETE removes users from a group"""
         group = self.find_group(name)
         data = self.get_json_body()

jupyterhub/apihandlers/proxy.py

@@ -16,29 +16,26 @@ from .base import APIHandler
 class ProxyAPIHandler(APIHandler):
 
     @admin_only
-    @gen.coroutine
+    async def get(self):
-    def get(self):
         """GET /api/proxy fetches the routing table
 
         This is the same as fetching the routing table directly from the proxy,
         but without clients needing to maintain separate
         """
-        routes = yield self.proxy.get_all_routes()
+        routes = await self.proxy.get_all_routes()
         self.write(json.dumps(routes))
 
     @admin_only
-    @gen.coroutine
+    async def post(self):
-    def post(self):
         """POST checks the proxy to ensure that it's up to date.
 
         Can be used to jumpstart a newly launched proxy
         without waiting for the check_routes interval.
         """
-        yield self.proxy.check_routes(self.users, self.services)
+        await self.proxy.check_routes(self.users, self.services)
 
     @admin_only
-    @gen.coroutine
+    async def patch(self):
-    def patch(self):
         """PATCH updates the location of the proxy
 
         Can be used to notify the Hub that a new proxy is in charge
@@ -58,8 +55,7 @@ class ProxyAPIHandler(APIHandler):
         if 'auth_token' in model:
             self.proxy.auth_token = model['auth_token']
         self.log.info("Updated proxy at %s", self.proxy)
-        yield self.proxy.check_routes(self.users, self.services)
+        await self.proxy.check_routes(self.users, self.services)
-        
 
 
 default_handlers = [

jupyterhub/apihandlers/services.py

@@ -23,6 +23,7 @@ def service_model(service):
         'prefix': service.server.base_url if service.server else '',
         'command': service.command,
         'pid': service.proc.pid if service.proc else 0,
+        'info': service.info
     }
 
 class ServiceListAPIHandler(APIHandler):

jupyterhub/apihandlers/users.py

@@ -3,12 +3,17 @@
 # Copyright (c) Jupyter Development Team.
 # Distributed under the terms of the Modified BSD License.
 
+import asyncio
+from datetime import datetime
 import json
 
-from tornado import gen, web
+from async_generator import aclosing
+from tornado import  web
+from tornado.iostream import StreamClosedError
 
 from .. import orm
-from ..utils import admin_only
+from ..user import User
+from ..utils import admin_only, iterate_until, maybe_future, url_path_join
 from .base import APIHandler
 
 
@@ -17,8 +22,8 @@ class SelfAPIHandler(APIHandler):
 
     Based on the authentication info. Acts as a 'whoami' for auth tokens.
     """
-    @web.authenticated
+
-    def get(self):
+    async def get(self):
         user = self.get_current_user()
         if user is None:
             # whoami can be accessed via oauth token
@@ -31,13 +36,14 @@ class SelfAPIHandler(APIHandler):
 class UserListAPIHandler(APIHandler):
     @admin_only
     def get(self):
-        users = [ self._user_from_orm(u) for u in self.db.query(orm.User) ]
+        data = [
-        data = [ self.user_model(u) for u in users ]
+            self.user_model(u, include_servers=True, include_state=True)
+            for u in self.db.query(orm.User)
+        ]
         self.write(json.dumps(data))
 
     @admin_only
-    @gen.coroutine
+    async def post(self):
-    def post(self):
         data = self.get_json_body()
         if not data or not isinstance(data, dict) or not data.get('usernames'):
             raise web.HTTPError(400, "Must specify at least one user to create")
@@ -69,7 +75,7 @@ class UserListAPIHandler(APIHandler):
             raise web.HTTPError(400, msg)
 
         if not to_create:
-            raise web.HTTPError(400, "All %i users already exist" % len(usernames))
+            raise web.HTTPError(409, "All %i users already exist" % len(usernames))
 
         created = []
         for name in to_create:
@@ -78,10 +84,10 @@ class UserListAPIHandler(APIHandler):
                 user.admin = True
                 self.db.commit()
             try:
-                yield gen.maybe_future(self.authenticator.add_user(user))
+                await maybe_future(self.authenticator.add_user(user))
             except Exception as e:
                 self.log.error("Failed to create user: %s" % name, exc_info=True)
-                del self.users[user]
+                self.users.delete(user)
                 raise web.HTTPError(400, "Failed to create user %s: %s" % (name, str(e)))
             else:
                 created.append(user)
@@ -105,20 +111,28 @@ def admin_or_self(method):
         return method(self, name, *args, **kwargs)
     return m
 
+
 class UserAPIHandler(APIHandler):
 
     @admin_or_self
-    def get(self, name):
+    async def get(self, name):
         user = self.find_user(name)
-        self.write(json.dumps(self.user_model(user)))
+        model = self.user_model(user, include_servers=True, include_state=self.get_current_user().admin)
+        # auth state will only be shown if the requestor is an admin
+        # this means users can't see their own auth state unless they
+        # are admins, Hub admins often are also marked as admins so they
+        # will see their auth state but normal users won't
+        requestor = self.get_current_user()
+        if requestor.admin:
+            model['auth_state'] = await user.get_auth_state()
+        self.write(json.dumps(model))
 
     @admin_only
-    @gen.coroutine
+    async def post(self, name):
-    def post(self, name):
         data = self.get_json_body()
         user = self.find_user(name)
         if user is not None:
-            raise web.HTTPError(400, "User %s already exists" % name)
+            raise web.HTTPError(409, "User %s already exists" % name)
 
         user = self.user_from_username(name)
         if data:
@@ -128,19 +142,18 @@ class UserAPIHandler(APIHandler):
                 self.db.commit()
 
         try:
-            yield gen.maybe_future(self.authenticator.add_user(user))
+            await maybe_future(self.authenticator.add_user(user))
         except Exception:
             self.log.error("Failed to create user: %s" % name, exc_info=True)
             # remove from registry
-            del self.users[user]
+            self.users.delete(user)
             raise web.HTTPError(400, "Failed to create user: %s" % name)
 
         self.write(json.dumps(self.user_model(user)))
         self.set_status(201)
 
     @admin_only
-    @gen.coroutine
+    async def delete(self, name):
-    def delete(self, name):
         user = self.find_user(name)
         if user is None:
             raise web.HTTPError(404)
@@ -149,18 +162,18 @@ class UserAPIHandler(APIHandler):
         if user.spawner._stop_pending:
             raise web.HTTPError(400, "%s's server is in the process of stopping, please wait." % name)
         if user.running:
-            yield self.stop_single_user(user)
+            await self.stop_single_user(user)
             if user.spawner._stop_pending:
                 raise web.HTTPError(400, "%s's server is in the process of stopping, please wait." % name)
 
-        yield gen.maybe_future(self.authenticator.delete_user(user))
+        await maybe_future(self.authenticator.delete_user(user))
         # remove from registry
-        del self.users[user]
+        self.users.delete(user)
 
         self.set_status(204)
 
     @admin_only
-    def patch(self, name):
+    async def patch(self, name):
         user = self.find_user(name)
         if user is None:
             raise web.HTTPError(404)
@@ -171,17 +184,168 @@ class UserAPIHandler(APIHandler):
             if self.find_user(data['name']):
                 raise web.HTTPError(400, "User %s already exists, username must be unique" % data['name'])
         for key, value in data.items():
-            setattr(user, key, value)
+            if key == 'auth_state':
+                await user.save_auth_state(value)
+            else:
+                setattr(user, key, value)
         self.db.commit()
-        self.write(json.dumps(self.user_model(user)))
+        user_ = self.user_model(user)
+        user_['auth_state'] = await user.get_auth_state()
+        self.write(json.dumps(user_))
+
+
+class UserTokenListAPIHandler(APIHandler):
+    """API endpoint for listing/creating tokens"""
+    @admin_or_self
+    def get(self, name):
+        """Get tokens for a given user"""
+        user = self.find_user(name)
+        if not user:
+            raise web.HTTPError(404, "No such user: %s" % name)
+
+        now = datetime.utcnow()
+
+        api_tokens = []
+        def sort_key(token):
+            return token.last_activity or token.created
+
+        for token in sorted(user.api_tokens, key=sort_key):
+            if token.expires_at and token.expires_at < now:
+                # exclude expired tokens
+                self.db.delete(token)
+                self.db.commit()
+                continue
+            api_tokens.append(self.token_model(token))
+
+        oauth_tokens = []
+        # OAuth tokens use integer timestamps
+        now_timestamp = now.timestamp()
+        for token in sorted(user.oauth_tokens, key=sort_key):
+            if token.expires_at and token.expires_at < now_timestamp:
+                # exclude expired tokens
+                self.db.delete(token)
+                self.db.commit()
+                continue
+            oauth_tokens.append(self.token_model(token))
+        self.write(json.dumps({
+            'api_tokens': api_tokens,
+            'oauth_tokens': oauth_tokens,
+        }))
+
+    async def post(self, name):
+        body = self.get_json_body() or {}
+        if not isinstance(body, dict):
+            raise web.HTTPError(400, "Body must be a JSON dict or empty")
+
+        requester = self.get_current_user()
+        if requester is None:
+            # defer to Authenticator for identifying the user
+            # can be username+password or an upstream auth token
+            try:
+                name = await self.authenticator.authenticate(self, body.get('auth'))
+            except web.HTTPError as e:
+                # turn any authentication error into 403
+                raise web.HTTPError(403)
+            except Exception as e:
+                # suppress and log error here in case Authenticator
+                # isn't prepared to handle auth via this data
+                self.log.error("Error authenticating request for %s: %s",
+                    self.request.uri, e)
+                raise web.HTTPError(403)
+            requester = self.find_user(name)
+        if requester is None:
+            # couldn't identify requester
+            raise web.HTTPError(403)
+        user = self.find_user(name)
+        if requester is not user and not requester.admin:
+            raise web.HTTPError(403, "Only admins can request tokens for other users")
+        if not user:
+            raise web.HTTPError(404, "No such user: %s" % name)
+        if requester is not user:
+            kind = 'user' if isinstance(requester, User) else 'service'
+
+        note = body.get('note')
+        if not note:
+            note = "Requested via api"
+            if requester is not user:
+                note += " by %s %s" % (kind, requester.name)
+
+        api_token = user.new_api_token(note=note, expires_in=body.get('expires_in', None))
+        if requester is not user:
+            self.log.info("%s %s requested API token for %s", kind.title(), requester.name, user.name)
+        else:
+            user_kind = 'user' if isinstance(user, User) else 'service'
+            self.log.info("%s %s requested new API token", user_kind.title(), user.name)
+        # retrieve the model
+        token_model = self.token_model(orm.APIToken.find(self.db, api_token))
+        token_model['token'] = api_token
+        self.write(json.dumps(token_model))
+
+
+class UserTokenAPIHandler(APIHandler):
+    """API endpoint for retrieving/deleting individual tokens"""
+
+    def find_token_by_id(self, user, token_id):
+        """Find a token object by token-id key
+
+        Raises 404 if not found for any reason
+        (e.g. wrong owner, invalid key format, etc.)
+        """
+        not_found = "No such token %s for user %s" % (token_id, user.name)
+        prefix, id = token_id[0], token_id[1:]
+        if prefix == 'a':
+            Token = orm.APIToken
+        elif prefix == 'o':
+            Token = orm.OAuthAccessToken
+        else:
+            raise web.HTTPError(404, not_found)
+        try:
+            id = int(id)
+        except ValueError:
+            raise web.HTTPError(404, not_found)
+
+        orm_token = self.db.query(Token).filter(Token.id==id).first()
+        if orm_token is None or orm_token.user is not user.orm_user:
+            raise web.HTTPError(404, "Token not found %s", orm_token)
+        return orm_token
+
+    @admin_or_self
+    def get(self, name, token_id):
+        """"""
+        user = self.find_user(name)
+        if not user:
+            raise web.HTTPError(404, "No such user: %s" % name)
+        token = self.find_token_by_id(user, token_id)
+        self.write(json.dumps(self.token_model(token)))
+
+    @admin_or_self
+    def delete(self, name, token_id):
+        """Delete a token"""
+        user = self.find_user(name)
+        if not user:
+            raise web.HTTPError(404, "No such user: %s" % name)
+        token = self.find_token_by_id(user, token_id)
+        # deleting an oauth token deletes *all* oauth tokens for that client
+        if isinstance(token, orm.OAuthAccessToken):
+            client_id = token.client_id
+            tokens = [
+                token for token in user.oauth_tokens
+                if token.client_id == client_id
+            ]
+        else:
+            tokens = [token]
+        for token in tokens:
+            self.db.delete(token)
+        self.db.commit()
+        self.set_header('Content-Type', 'text/plain')
+        self.set_status(204)
 
 
 class UserServerAPIHandler(APIHandler):
     """Start and stop single-user servers"""
 
-    @gen.coroutine
     @admin_or_self
-    def post(self, name, server_name=''):
+    async def post(self, name, server_name=''):
         user = self.find_user(name)
         if server_name and not self.allow_named_servers:
             raise web.HTTPError(400, "Named servers are not enabled.")
@@ -199,21 +363,20 @@ class UserServerAPIHandler(APIHandler):
             # set _spawn_pending flag to prevent races while we wait
             spawner._spawn_pending = True
             try:
-                state = yield spawner.poll_and_notify()
+                state = await spawner.poll_and_notify()
             finally:
                 spawner._spawn_pending = False
             if state is None:
                 raise web.HTTPError(400, "%s is already running" % spawner._log_name)
 
         options = self.get_json_body()
-        yield self.spawn_single_user(user, server_name, options=options)
+        await self.spawn_single_user(user, server_name, options=options)
         status = 202 if spawner.pending == 'spawn' else 201
         self.set_header('Content-Type', 'text/plain')
         self.set_status(status)
 
-    @gen.coroutine
     @admin_or_self
-    def delete(self, name, server_name=''):
+    async def delete(self, name, server_name=''):
         user = self.find_user(name)
         if server_name:
             if not self.allow_named_servers:
@@ -234,10 +397,10 @@ class UserServerAPIHandler(APIHandler):
                 (spawner._log_name, '(pending: %s)' % spawner.pending if spawner.pending else '')
             )
         # include notify, so that a server that died is noticed immediately
-        status = yield spawner.poll_and_notify()
+        status = await spawner.poll_and_notify()
         if status is not None:
             raise web.HTTPError(400, "%s is not running" % spawner._log_name)
-        yield self.stop_single_user(user, server_name)
+        await self.stop_single_user(user, server_name)
         status = 202 if spawner._stop_pending else 204
         self.set_header('Content-Type', 'text/plain')
         self.set_status(status)
@@ -263,11 +426,131 @@ class UserAdminAccessAPIHandler(APIHandler):
             raise web.HTTPError(404)
 
 
+class SpawnProgressAPIHandler(APIHandler):
+    """EventStream handler for pending spawns"""
+
+    keepalive_interval = 8
+
+    def get_content_type(self):
+        return 'text/event-stream'
+
+    async def send_event(self, event):
+        try:
+            self.write('data: {}\n\n'.format(json.dumps(event)))
+            await self.flush()
+        except StreamClosedError:
+            self.log.warning("Stream closed while handling %s", self.request.uri)
+            # raise Finish to halt the handler
+            raise web.Finish()
+
+    _finished = False
+    def on_finish(self):
+        self._finished = True
+
+    async def keepalive(self):
+        """Write empty lines periodically
+
+        to avoid being closed by intermediate proxies
+        when there's a large gap between events.
+        """
+        while not self._finished:
+            try:
+                self.write("\n\n")
+            except (StreamClosedError, RuntimeError):
+                return
+            await asyncio.sleep(self.keepalive_interval)
+
+    @admin_or_self
+    async def get(self, username, server_name=''):
+        self.set_header('Cache-Control', 'no-cache')
+        if server_name is None:
+            server_name = ''
+        user = self.find_user(username)
+        if user is None:
+            # no such user
+            raise web.HTTPError(404)
+        if server_name not in user.spawners:
+            # user has no such server
+            raise web.HTTPError(404)
+        spawner = user.spawners[server_name]
+
+        # start sending keepalive to avoid proxies closing the connection
+        asyncio.ensure_future(self.keepalive())
+        # cases:
+        # - spawner already started and ready
+        # - spawner not running at all
+        # - spawner failed
+        # - spawner pending start (what we expect)
+        url = url_path_join(user.url, server_name, '/')
+        ready_event = {
+            'progress': 100,
+            'ready': True,
+            'message': "Server ready at {}".format(url),
+            'html_message': 'Server ready at <a href="{0}">{0}</a>'.format(url),
+            'url': url,
+        }
+        failed_event = {
+            'progress': 100,
+            'failed': True,
+            'message': "Spawn failed",
+        }
+
+        if spawner.ready:
+            # spawner already ready. Trigger progress-completion immediately
+            self.log.info("Server %s is already started", spawner._log_name)
+            await self.send_event(ready_event)
+            return
+
+        spawn_future = spawner._spawn_future
+
+        if not spawner._spawn_pending:
+            # not pending, no progress to fetch
+            # check if spawner has just failed
+            f = spawn_future
+            if f and f.done() and f.exception():
+                failed_event['message'] = "Spawn failed: %s" % f.exception()
+                await self.send_event(failed_event)
+                return
+            else:
+                raise web.HTTPError(400, "%s is not starting...", spawner._log_name)
+
+        # retrieve progress events from the Spawner
+        async with aclosing(iterate_until(spawn_future, spawner._generate_progress())) as events:
+            async for event in events:
+                # don't allow events to sneakily set the 'ready' flag
+                if 'ready' in event:
+                    event.pop('ready', None)
+                await self.send_event(event)
+
+        # progress finished, wait for spawn to actually resolve,
+        # in case progress finished early
+        # (ignore errors, which will be logged elsewhere)
+        await asyncio.wait([spawn_future])
+
+        # progress and spawn finished, check if spawn succeeded
+        if spawner.ready:
+            # spawner is ready, signal completion and redirect
+            self.log.info("Server %s is ready", spawner._log_name)
+            await self.send_event(ready_event)
+        else:
+            # what happened? Maybe spawn failed?
+            f = spawn_future
+            if f and f.done() and f.exception():
+                failed_event['message'] = "Spawn failed: %s" % f.exception()
+            else:
+                self.log.warning("Server %s didn't start for unknown reason", spawner._log_name)
+            await self.send_event(failed_event)
+
+
 default_handlers = [
     (r"/api/user", SelfAPIHandler),
     (r"/api/users", UserListAPIHandler),
     (r"/api/users/([^/]+)", UserAPIHandler),
     (r"/api/users/([^/]+)/server", UserServerAPIHandler),
+    (r"/api/users/([^/]+)/server/progress", SpawnProgressAPIHandler),
+    (r"/api/users/([^/]+)/tokens", UserTokenListAPIHandler),
+    (r"/api/users/([^/]+)/tokens/([^/]*)", UserTokenAPIHandler),
     (r"/api/users/([^/]+)/servers/([^/]*)", UserServerAPIHandler),
+    (r"/api/users/([^/]+)/servers/([^/]*)/progress", SpawnProgressAPIHandler),
     (r"/api/users/([^/]+)/admin-access", UserAdminAccessAPIHandler),
 ]

jupyterhub/auth.py

@@ -3,28 +3,30 @@
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
+from concurrent.futures import ThreadPoolExecutor
 import pipes
 import re
 from shutil import which
 import sys
 from subprocess import Popen, PIPE, STDOUT
 
-from tornado import gen
 try:
     import pamela
 except Exception as e:
     pamela = None
     _pamela_error = e
 
+from tornado.concurrent import run_on_executor
+from tornado import gen
+
 from traitlets.config import LoggingConfigurable
 from traitlets import Bool, Set, Unicode, Dict, Any, default, observe
 
 from .handlers.login import LoginHandler
-from .utils import url_path_join
+from .utils import maybe_future, url_path_join
 from .traitlets import Command
 
 
-
 def getgrnam(name):
     """Wrapper function to protect against `grp` not being available
     on Windows
@@ -47,7 +49,7 @@ class Authenticator(LoggingConfigurable):
 
         Encrypting auth_state requires the cryptography package.
 
-        Additionally, the JUPYTERHUB_CRYPTO_KEY envirionment variable must
+        Additionally, the JUPYTERHUB_CRYPT_KEY environment variable must
         contain one (or more, separated by ;) 32B encryption keys.
         These can be either base64 or hex-encoded.
 
@@ -86,6 +88,20 @@ class Authenticator(LoggingConfigurable):
         """
     ).tag(config=True)
 
+    blacklist = Set(
+        help="""
+        Blacklist of usernames that are not allowed to log in.
+
+        Use this with supported authenticators to restrict which users can not log in. This is an
+        additional blacklist that further restricts users, beyond whatever restrictions the
+        authenticator has in place.
+
+        If empty, does not perform any additional restriction.
+
+        .. versionadded: 0.9
+        """
+    ).tag(config=True)
+
     @observe('whitelist')
     def _check_whitelist(self, change):
         short_names = [name for name in change['new'] if len(name) <= 1]
@@ -203,8 +219,22 @@ class Authenticator(LoggingConfigurable):
             return True
         return username in self.whitelist
 
-    @gen.coroutine
+    def check_blacklist(self, username):
-    def get_authenticated_user(self, handler, data):
+        """Check if a username is blocked to authenticate based on blacklist configuration
+
+        Return True if username is allowed, False otherwise.
+        No blacklist means any username is allowed.
+
+        Names are normalized *before* being checked against the blacklist.
+
+        .. versionadded: 0.9
+        """
+        if not self.blacklist:
+            # No blacklist means any name is allowed
+            return True
+        return username not in self.blacklist
+
+    async def get_authenticated_user(self, handler, data):
         """Authenticate the user who is attempting to log in
 
         Returns user dict if successful, None otherwise.
@@ -224,7 +254,7 @@ class Authenticator(LoggingConfigurable):
         .. versionchanged:: 0.8
             return dict instead of username
         """
-        authenticated = yield self.authenticate(handler, data)
+        authenticated = await maybe_future(self.authenticate(handler, data))
         if authenticated is None:
             return
         if isinstance(authenticated, dict):
@@ -235,6 +265,7 @@ class Authenticator(LoggingConfigurable):
                 'name': authenticated,
             }
         authenticated.setdefault('auth_state', None)
+        authenticated.setdefault('admin', None)
 
         # normalize the username
         authenticated['name'] = username = self.normalize_username(authenticated['name'])
@@ -242,15 +273,21 @@ class Authenticator(LoggingConfigurable):
             self.log.warning("Disallowing invalid username %r.", username)
             return
 
-        whitelist_pass = yield gen.maybe_future(self.check_whitelist(username))
+        blacklist_pass = await maybe_future(self.check_blacklist(username))
+        whitelist_pass = await maybe_future(self.check_whitelist(username))
+        if blacklist_pass:
+            pass
+        else:
+            self.log.warning("User %r in blacklist. Stop authentication", username)
+            return
+
         if whitelist_pass:
             return authenticated
         else:
             self.log.warning("User %r not in whitelist.", username)
             return
 
-    @gen.coroutine
+    async def authenticate(self, handler, data):
-    def authenticate(self, handler, data):
         """Authenticate a user with login form data
 
         This must be a tornado gen.coroutine.
@@ -269,10 +306,10 @@ class Authenticator(LoggingConfigurable):
         Returns:
             user (str or dict or None): The username of the authenticated user,
                 or None if Authentication failed.
-                If the Authenticator has state associated with the user,
+                The Authenticator may return a dict instead, which MUST have a
-                it can return a dict with the keys 'name' and 'auth_state',
+                key 'name' holding the username, and may have two optional keys
-                where 'name' is the username and 'auth_state' is a dictionary
+                set - 'auth_state', a dictionary of of auth state that will be
-                of auth state that will be persisted.
+                persisted; and 'admin', the admin setting value for the user.
         """
 
     def pre_spawn_start(self, user, spawner):
@@ -475,20 +512,19 @@ class LocalAuthenticator(Authenticator):
                 return True
         return False
 
-    @gen.coroutine
+    async def add_user(self, user):
-    def add_user(self, user):
         """Hook called whenever a new user is added
 
         If self.create_system_users, the user will attempt to be created if it doesn't exist.
         """
-        user_exists = yield gen.maybe_future(self.system_user_exists(user))
+        user_exists = await maybe_future(self.system_user_exists(user))
         if not user_exists:
             if self.create_system_users:
-                yield gen.maybe_future(self.add_system_user(user))
+                await maybe_future(self.add_system_user(user))
             else:
                 raise KeyError("User %s does not exist." % user.name)
 
-        yield gen.maybe_future(super().add_user(user))
+        await maybe_future(super().add_user(user))
 
     @staticmethod
     def system_user_exists(user):
@@ -519,6 +555,12 @@ class LocalAuthenticator(Authenticator):
 class PAMAuthenticator(LocalAuthenticator):
     """Authenticate local UNIX users with PAM"""
 
+    # run PAM in a thread, since it can be slow
+    executor = Any()
+    @default('executor')
+    def _default_executor(self):
+        return ThreadPoolExecutor(1)
+
     encoding = Unicode('utf8',
         help="""
         The text encoding to use when communicating with PAM
@@ -544,12 +586,25 @@ class PAMAuthenticator(LocalAuthenticator):
         """
     ).tag(config=True)
 
+    check_account = Bool(True,
+        help="""
+        Whether to check the user's account status via PAM during authentication.
+
+        The PAM account stack performs non-authentication based account 
+        management. It is typically used to restrict/permit access to a 
+        service and this step is needed to access the host's user access control.
+
+        Disabling this can be dangerous as authenticated but unauthorized users may
+        be granted access and, therefore, arbitrary execution on the system.
+        """
+     ).tag(config=True)
+
     def __init__(self, **kwargs):
         if pamela is None:
             raise _pamela_error from None
         super().__init__(**kwargs)
 
-    @gen.coroutine
+    @run_on_executor
     def authenticate(self, handler, data):
         """Authenticate with PAM, and return the username if login is successful.
 
@@ -557,32 +612,44 @@ class PAMAuthenticator(LocalAuthenticator):
         """
         username = data['username']
         try:
-            pamela.authenticate(username, data['password'], service=self.service)
+            pamela.authenticate(username, data['password'], service=self.service, encoding=self.encoding)
         except pamela.PAMError as e:
             if handler is not None:
                 self.log.warning("PAM Authentication failed (%s@%s): %s", username, handler.request.remote_ip, e)
             else:
                 self.log.warning("PAM Authentication failed: %s", e)
         else:
-            return username
+            if not self.check_account:
+                return username
+            try:
+                pamela.check_account(username, service=self.service, encoding=self.encoding)
+            except pamela.PAMError as e:
+                if handler is not None:
+                    self.log.warning("PAM Account Check failed (%s@%s): %s", username, handler.request.remote_ip, e)
+                else:
+                    self.log.warning("PAM Account Check failed: %s", e)
+            else:
+                return username
 
+    @run_on_executor
     def pre_spawn_start(self, user, spawner):
         """Open PAM session for user if so configured"""
         if not self.open_sessions:
             return
         try:
-            pamela.open_session(user.name, service=self.service)
+            pamela.open_session(user.name, service=self.service, encoding=self.encoding)
         except pamela.PAMError as e:
             self.log.warning("Failed to open PAM session for %s: %s", user.name, e)
             self.log.warning("Disabling PAM sessions from now on.")
             self.open_sessions = False
 
+    @run_on_executor
     def post_spawn_stop(self, user, spawner):
         """Close PAM session for user if we were configured to opened one"""
         if not self.open_sessions:
             return
         try:
-            pamela.close_session(user.name, service=self.service)
+            pamela.close_session(user.name, service=self.service, encoding=self.encoding)
         except pamela.PAMError as e:
             self.log.warning("Failed to close PAM session for %s: %s", user.name, e)
             self.log.warning("Disabling PAM sessions from now on.")

jupyterhub/crypto.py

@@ -19,6 +19,7 @@ except ImportError:
     class InvalidToken(Exception):
         pass
 
+from .utils import maybe_future
 
 KEY_ENV = 'JUPYTERHUB_CRYPT_KEY'
 
@@ -132,7 +133,7 @@ class CryptKeeper(SingletonConfigurable):
     def encrypt(self, data):
         """Encrypt an object with cryptography"""
         self.check_available()
-        return self.executor.submit(self._encrypt, data)
+        return maybe_future(self.executor.submit(self._encrypt, data))
 
     def _decrypt(self, encrypted):
         decrypted = self.fernet.decrypt(encrypted)
@@ -141,7 +142,7 @@ class CryptKeeper(SingletonConfigurable):
     def decrypt(self, encrypted):
         """Decrypt an object with cryptography"""
         self.check_available()
-        return self.executor.submit(self._decrypt, encrypted)
+        return maybe_future(self.executor.submit(self._decrypt, encrypted))
 
 
 def encrypt(data):
@@ -158,4 +159,3 @@ def decrypt(data):
     Returns a Future whose result will be the decrypted, deserialized data.
     """
     return CryptKeeper.instance().decrypt(data)
-    

jupyterhub/dbutil.py

@@ -130,13 +130,51 @@ def upgrade_if_needed(db_url, backup=True, log=None):
     upgrade(db_url)
 
 
-def _alembic(*args):
+def shell(args=None):
+    """Start an IPython shell hooked up to the jupyerhub database"""
+    from .app import JupyterHub
+    hub = JupyterHub()
+    hub.load_config_file(hub.config_file)
+    db_url = hub.db_url
+    db = orm.new_session_factory(db_url, **hub.db_kwargs)()
+    ns = {
+        'db': db,
+        'db_url': db_url,
+        'orm': orm,
+    }
+
+    import IPython
+    IPython.start_ipython(args, user_ns=ns)
+
+
+def _alembic(args):
     """Run an alembic command with a temporary alembic.ini"""
-    with _temp_alembic_ini('sqlite:///jupyterhub.sqlite') as alembic_ini:
+    from .app import JupyterHub
+    hub = JupyterHub()
+    hub.load_config_file(hub.config_file)
+    db_url = hub.db_url
+    with _temp_alembic_ini(db_url) as alembic_ini:
         check_call(
-            ['alembic', '-c', alembic_ini] + list(args)
+            ['alembic', '-c', alembic_ini] + args
         )
 
 
+def main(args=None):
+    if args is None:
+        args = sys.argv[1:]
+    # dumb option parsing, since we want to pass things through
+    # to subcommands
+    choices = ['shell', 'alembic']
+    if not args or args[0] not in choices:
+        print("Select a command from: %s" % ', '.join(choices))
+        return 1
+    cmd, args = args[0], args[1:]
+
+    if cmd == 'shell':
+        shell(args)
+    elif cmd == 'alembic':
+        _alembic(args)
+
+
 if __name__ == '__main__':
-    _alembic(*sys.argv[1:])
+    sys.exit(main())

jupyterhub/handlers/__init__.py

@@ -1,8 +1,8 @@
 from .base import *
 from .login import *
 
-from . import base, pages, login
+from . import base, pages, login, metrics
 
 default_handlers = []
-for mod in (base, pages, login):
+for mod in (base, pages, login, metrics):
     default_handlers.extend(mod.default_handlers)

jupyterhub/handlers/base.py

@@ -4,15 +4,21 @@
 # Distributed under the terms of the Modified BSD License.
 
 import copy
-import re
+from datetime import datetime, timedelta
-from datetime import timedelta
 from http.client import responses
+import json
+import math
+import random
+import re
+import time
 from urllib.parse import urlparse, urlunparse, parse_qs, urlencode
+import uuid
 
 from jinja2 import TemplateNotFound
 
+from sqlalchemy.exc import SQLAlchemyError
 from tornado.log import app_log
-from tornado.httputil import url_concat
+from tornado.httputil import url_concat, HTTPHeaders
 from tornado.ioloop import IOLoop
 from tornado.web import RequestHandler
 from tornado import gen, web
@@ -21,7 +27,11 @@ from .. import __version__
 from .. import orm
 from ..objects import Server
 from ..spawner import LocalProcessSpawner
-from ..utils import url_path_join
+from ..utils import maybe_future, url_path_join
+from ..metrics import (
+    SERVER_SPAWN_DURATION_SECONDS, ServerSpawnStatus,
+    PROXY_ADD_DURATION_SECONDS, ProxyAddStatus,
+)
 
 # pattern for the authentication token header
 auth_header_pat = re.compile(r'^(?:token|bearer)\s+([^\s]+)$', flags=re.IGNORECASE)
@@ -31,9 +41,13 @@ reasons = {
     'timeout': "Failed to reach your server."
         "  Please try again later."
         "  Contact admin if the issue persists.",
-    'error': "Failed to start your server.  Please contact admin.",
+    'error': "Failed to start your server on the last attempt.  "
+        "  Please contact admin if the issue persists.",
 }
 
+# constant, not configurable
+SESSION_COOKIE_NAME = 'jupyterhub-session-id'
+
 class BaseHandler(RequestHandler):
     """Base Handler class with access to common methods and properties."""
 
@@ -50,6 +64,10 @@ class BaseHandler(RequestHandler):
     def base_url(self):
         return self.settings.get('base_url', '/')
 
+    @property
+    def default_url(self):
+        return self.settings.get('default_url', '')
+
     @property
     def version_hash(self):
         return self.settings.get('version_hash', '')
@@ -77,6 +95,7 @@ class BaseHandler(RequestHandler):
     @property
     def services(self):
         return self.settings.setdefault('services', {})
+
     @property
     def hub(self):
         return self.settings['hub']
@@ -125,20 +144,28 @@ class BaseHandler(RequestHandler):
             "report-uri " + self.csp_report_uri,
         ])
 
+    def get_content_type(self):
+        return 'text/html'
+
     def set_default_headers(self):
         """
         Set any headers passed as tornado_settings['headers'].
 
         By default sets Content-Security-Policy of frame-ancestors 'self'.
+        Also responsible for setting content-type header
         """
-        headers = self.settings.get('headers', {})
+        # wrap in HTTPHeaders for case-insensitivity
+        headers = HTTPHeaders(self.settings.get('headers', {}))
         headers.setdefault("X-JupyterHub-Version", __version__)
 
         for header_name, header_content in headers.items():
             self.set_header(header_name, header_content)
 
+        if 'Access-Control-Allow-Headers' not in headers:
+            self.set_header('Access-Control-Allow-Headers', 'accept, content-type, authorization')
         if 'Content-Security-Policy' not in headers:
             self.set_header('Content-Security-Policy', self.content_security_policy)
+        self.set_header('Content-Type', self.get_content_type())
 
     #---------------------------------------------------------------
     # Login and cookie-related
@@ -152,6 +179,10 @@ class BaseHandler(RequestHandler):
     def cookie_max_age_days(self):
         return self.settings.get('cookie_max_age_days', None)
 
+    @property
+    def redirect_to_server(self):
+        return self.settings.get('redirect_to_server', True)
+
     def get_auth_token(self):
         """Get the authorization token from Authorization header"""
         auth_header = self.request.headers.get('Authorization', '')
@@ -173,8 +204,10 @@ class BaseHandler(RequestHandler):
         orm_token = orm.OAuthAccessToken.find(self.db, token)
         if orm_token is None:
             return None
-        else:
+        orm_token.last_activity = \
-            return self._user_from_orm(orm_token.user)
+            orm_token.user.last_activity = datetime.utcnow()
+        self.db.commit()
+        return self._user_from_orm(orm_token.user)
 
     def get_current_user_token(self):
         """get_current_user from Authorization header token"""
@@ -185,6 +218,13 @@ class BaseHandler(RequestHandler):
         if orm_token is None:
             return None
         else:
+            # record token activity
+            now = datetime.utcnow()
+            orm_token.last_activity = now
+            if orm_token.user:
+                orm_token.user.last_activity = now
+
+            self.db.commit()
             return orm_token.service or self._user_from_orm(orm_token.user)
 
     def _user_for_cookie(self, cookie_name, cookie_value=None):
@@ -209,6 +249,10 @@ class BaseHandler(RequestHandler):
             self.log.warning("Invalid cookie token")
             # have cookie, but it's not valid. Clear it and start over.
             clear()
+            return
+        # update user activity
+        user.last_activity = datetime.utcnow()
+        self.db.commit()
         return user
 
     def _user_from_orm(self, orm_user):
@@ -223,10 +267,17 @@ class BaseHandler(RequestHandler):
 
     def get_current_user(self):
         """get current username"""
-        user = self.get_current_user_token()
+        if not hasattr(self, '_jupyterhub_user'):
-        if user is not None:
+            try:
-            return user
+                user = self.get_current_user_token()
-        return self.get_current_user_cookie()
+                if user is None:
+                    user = self.get_current_user_cookie()
+                self._jupyterhub_user = user
+            except Exception:
+                # don't let errors here raise more than once
+                self._jupyterhub_user = None
+                raise
+        return self._jupyterhub_user
 
     def find_user(self, name):
         """Get a user by name
@@ -245,17 +296,46 @@ class BaseHandler(RequestHandler):
             self.db.add(u)
             self.db.commit()
             user = self._user_from_orm(u)
-            self.authenticator.add_user(user)
         return user
 
     def clear_login_cookie(self, name=None):
         kwargs = {}
         if self.subdomain_host:
             kwargs['domain'] = self.domain
-        self.clear_cookie(self.hub.cookie_name, path=self.hub.base_url, **kwargs)
+        user = self.get_current_user_cookie()
-        self.clear_cookie('jupyterhub-services', path=url_path_join(self.base_url, 'services'))
+        session_id = self.get_session_cookie()
+        if session_id:
+            # clear session id
+            self.clear_cookie(SESSION_COOKIE_NAME, **kwargs)
 
-    def _set_user_cookie(self, user, server):
+            if user:
+                # user is logged in, clear any tokens associated with the current session
+                # don't clear session tokens if not logged in,
+                # because that could be a malicious logout request!
+                count = 0
+                for access_token in (
+                    self.db.query(orm.OAuthAccessToken)
+                    .filter(orm.OAuthAccessToken.user_id==user.id)
+                    .filter(orm.OAuthAccessToken.session_id==session_id)
+                ):
+                    self.db.delete(access_token)
+                    count += 1
+                if count:
+                    self.log.debug("Deleted %s access tokens for %s", count, user.name)
+                    self.db.commit()
+
+
+        # clear hub cookie
+        self.clear_cookie(self.hub.cookie_name, path=self.hub.base_url, **kwargs)
+        # clear services cookie
+        self.clear_cookie('jupyterhub-services', path=url_path_join(self.base_url, 'services'), **kwargs)
+
+    def _set_cookie(self, key, value, encrypted=True, **overrides):
+        """Setting any cookie should go through here
+
+        if encrypted use tornado's set_secure_cookie,
+        otherwise set plaintext cookies.
+        """
         # tornado <4.2 have a bug that consider secure==True as soon as
         # 'secure' kwarg is passed to set_secure_cookie
         kwargs = {
@@ -265,14 +345,47 @@ class BaseHandler(RequestHandler):
             kwargs['secure'] = True
         if self.subdomain_host:
             kwargs['domain'] = self.domain
-        self.log.debug("Setting cookie for %s: %s, %s", user.name, server.cookie_name, kwargs)
+
-        self.set_secure_cookie(
+        kwargs.update(self.settings.get('cookie_options', {}))
+        kwargs.update(overrides)
+
+        if encrypted:
+            set_cookie = self.set_secure_cookie
+        else:
+            set_cookie = self.set_cookie
+
+        self.log.debug("Setting cookie %s: %s", key, kwargs)
+        set_cookie(key, value, **kwargs)
+
+
+    def _set_user_cookie(self, user, server):
+        self.log.debug("Setting cookie for %s: %s", user.name, server.cookie_name)
+        self._set_cookie(
             server.cookie_name,
             user.cookie_id,
+            encrypted=True,
             path=server.base_url,
-            **kwargs
         )
 
+    def get_session_cookie(self):
+        """Get the session id from a cookie
+
+        Returns None if no session id is stored
+        """
+        return self.get_cookie(SESSION_COOKIE_NAME, None)
+
+    def set_session_cookie(self):
+        """Set a new session id cookie
+
+        new session id is returned
+
+        Session id cookie is *not* encrypted,
+        so other services on this domain can read it.
+        """
+        session_id = uuid.uuid4().hex
+        self._set_cookie(SESSION_COOKIE_NAME, session_id, encrypted=False)
+        return session_id
+
     def set_service_cookie(self, user):
         """set the login cookie for services"""
         self._set_user_cookie(user, orm.Server(
@@ -295,50 +408,90 @@ class BaseHandler(RequestHandler):
         if self.db.query(orm.Service).filter(orm.Service.server != None).first():
             self.set_service_cookie(user)
 
+        if not self.get_session_cookie():
+            self.set_session_cookie()
+
         # create and set a new cookie token for the hub
         if not self.get_current_user_cookie():
             self.set_hub_cookie(user)
 
     def authenticate(self, data):
-        return gen.maybe_future(self.authenticator.get_authenticated_user(self, data))
+        return maybe_future(self.authenticator.get_authenticated_user(self, data))
 
     def get_next_url(self, user=None):
         """Get the next_url for login redirect
 
-        Defaults to hub base_url /hub/ if user is not running,
+        Default URL after login:
-        otherwise user.url.
+
+        - if redirect_to_server (default): send to user's own server
+        - else: /hub/home
         """
         next_url = self.get_argument('next', default='')
-        if (next_url + '/').startswith('%s://%s/' % (self.request.protocol, self.request.host)):
+        if (next_url + '/').startswith(
+            (
+                '%s://%s/' % (self.request.protocol, self.request.host),
+                '//%s/' % self.request.host,
+            )
+        ):
             # treat absolute URLs for our host as absolute paths:
-            next_url = urlparse(next_url).path
+            parsed = urlparse(next_url)
-        if not next_url.startswith('/'):
+            next_url = parsed.path
+            if parsed.query:
+                next_url = next_url + '?' + parsed.query
+            if parsed.hash:
+                next_url = next_url + '#' + parsed.hash
+        if next_url and (urlparse(next_url).netloc or not next_url.startswith('/')):
+            self.log.warning("Disallowing redirect outside JupyterHub: %r", next_url)
             next_url = ''
+        if next_url and next_url.startswith(url_path_join(self.base_url, 'user/')):
+            # add /hub/ prefix, to ensure we redirect to the right user's server.
+            # The next request will be handled by SpawnHandler,
+            # ultimately redirecting to the logged-in user's server.
+            without_prefix = next_url[len(self.base_url):]
+            next_url = url_path_join(self.hub.base_url, without_prefix)
+            self.log.warning("Redirecting %s to %s. For sharing public links, use /user-redirect/",
+                self.request.uri, next_url,
+            )
+
         if not next_url:
-            if user and user.running:
+            # custom default URL
+            next_url = self.default_url
+
+        if not next_url:
+            # default URL after login
+            # if self.redirect_to_server, default login URL initiates spawn,
+            # otherwise send to Hub home page (control panel)
+            if user and self.redirect_to_server:
                 next_url = user.url
             else:
-                next_url = self.hub.base_url
+                next_url = url_path_join(self.hub.base_url, 'home')
         return next_url
 
-    @gen.coroutine
+    async def login_user(self, data=None):
-    def login_user(self, data=None):
         """Login a user"""
         auth_timer = self.statsd.timer('login.authenticate').start()
-        authenticated = yield self.authenticate(data)
+        authenticated = await self.authenticate(data)
         auth_timer.stop(send=False)
 
         if authenticated:
             username = authenticated['name']
             auth_state = authenticated.get('auth_state')
+            admin = authenticated.get('admin')
+            new_user = username not in self.users
             user = self.user_from_username(username)
+            if new_user:
+                await maybe_future(self.authenticator.add_user(user))
+            # Only set `admin` if the authenticator returned an explicit value.
+            if admin is not None and admin != user.admin:
+                user.admin = admin
+                self.db.commit()
             # always set auth_state and commit,
             # because there could be key-rotation or clearing of previous values
             # going on.
             if not self.authenticator.enable_auth_state:
                 # auth_state is not enabled. Force None.
                 auth_state = None
-            yield user.save_auth_state(auth_state)
+            await user.save_auth_state(auth_state)
             self.db.commit()
             self.set_login_cookie(user)
             self.statsd.incr('login.success')
@@ -375,9 +528,9 @@ class BaseHandler(RequestHandler):
     def active_server_limit(self):
         return self.settings.get('active_server_limit', 0)
 
-    @gen.coroutine
+    async def spawn_single_user(self, user, server_name='', options=None):
-    def spawn_single_user(self, user, server_name='', options=None):
         # in case of error, include 'try again from /hub/home' message
+        spawn_start_time = time.perf_counter()
         self.extra_error_html = self.spawn_home_error
 
         user_server_name = user.name
@@ -387,6 +540,9 @@ class BaseHandler(RequestHandler):
 
         if server_name in user.spawners and user.spawners[server_name].pending:
             pending = user.spawners[server_name].pending
+            SERVER_SPAWN_DURATION_SECONDS.labels(
+                status=ServerSpawnStatus.already_pending
+            ).observe(time.perf_counter() - spawn_start_time)
             raise RuntimeError("%s pending %s" % (user_server_name, pending))
 
         # count active servers and pending spawns
@@ -401,26 +557,52 @@ class BaseHandler(RequestHandler):
         active_server_limit = self.active_server_limit
 
         if concurrent_spawn_limit and spawn_pending_count >= concurrent_spawn_limit:
-            self.log.info(
+            SERVER_SPAWN_DURATION_SECONDS.labels(
-                '%s pending spawns, throttling',
+                status=ServerSpawnStatus.throttled
-                spawn_pending_count,
+            ).observe(time.perf_counter() - spawn_start_time)
+            # Suggest number of seconds client should wait before retrying
+            # This helps prevent thundering herd problems, where users simply
+            # immediately retry when we are overloaded.
+            retry_range = self.settings['spawn_throttle_retry_range']
+            retry_time = int(random.uniform(*retry_range))
+
+            # round suggestion to nicer human value (nearest 10 seconds or minute)
+            if retry_time <= 90:
+                # round human seconds up to nearest 10
+                human_retry_time = "%i0 seconds" % math.ceil(retry_time / 10.)
+            else:
+                # round number of minutes
+                human_retry_time = "%i minutes" % math.round(retry_time / 60.)
+
+            self.log.warning(
+                '%s pending spawns, throttling. Suggested retry in %s seconds.',
+                spawn_pending_count, retry_time,
             )
-            raise web.HTTPError(
+            err = web.HTTPError(
                 429,
-                "User startup rate limit exceeded. Try again in a few minutes.",
+                "Too many users trying to log in right now. Try again in {}.".format(human_retry_time)
             )
+            # can't call set_header directly here because it gets ignored
+            # when errors are raised
+            # we handle err.headers ourselves in Handler.write_error
+            err.headers = {'Retry-After': retry_time}
+            raise err
+
         if active_server_limit and active_count >= active_server_limit:
             self.log.info(
                 '%s servers active, no space available',
                 active_count,
             )
+            SERVER_SPAWN_DURATION_SECONDS.labels(
+                status=ServerSpawnStatus.too_many_users
+            ).observe(time.perf_counter() - spawn_start_time)
             raise web.HTTPError(429, "Active user limit exceeded. Try again in a few minutes.")
 
         tic = IOLoop.current().time()
 
         self.log.debug("Initiating spawn for %s", user_server_name)
 
-        spawn_future = user.spawn(server_name, options)
+        spawn_future = user.spawn(server_name, options, handler=self)
 
         self.log.debug("%i%s concurrent spawns",
             spawn_pending_count,
@@ -434,25 +616,39 @@ class BaseHandler(RequestHandler):
         # while we are waiting for _proxy_pending to be set
         spawner._spawn_pending = True
 
-        @gen.coroutine
+        async def finish_user_spawn():
-        def finish_user_spawn():
             """Finish the user spawn by registering listeners and notifying the proxy.
 
             If the spawner is slow to start, this is passed as an async callback,
             otherwise it is called immediately.
             """
             # wait for spawn Future
-            yield spawn_future
+            await spawn_future
             toc = IOLoop.current().time()
             self.log.info("User %s took %.3f seconds to start", user_server_name, toc-tic)
             self.statsd.timing('spawner.success', (toc - tic) * 1000)
+            SERVER_SPAWN_DURATION_SECONDS.labels(
+                status=ServerSpawnStatus.success
+            ).observe(time.perf_counter() - spawn_start_time)
+            proxy_add_start_time = time.perf_counter()
             spawner._proxy_pending = True
             try:
-                yield self.proxy.add_user(user, server_name)
+                await self.proxy.add_user(user, server_name)
+
+                PROXY_ADD_DURATION_SECONDS.labels(
+                    status='success'
+                ).observe(
+                    time.perf_counter() - proxy_add_start_time
+                )
             except Exception:
                 self.log.exception("Failed to add %s to proxy!", user_server_name)
                 self.log.error("Stopping %s to avoid inconsistent state", user_server_name)
-                yield user.stop()
+                await user.stop()
+                PROXY_ADD_DURATION_SECONDS.labels(
+                    status='failure'
+                ).observe(
+                    time.perf_counter() - proxy_add_start_time
+                )
             else:
                 spawner.add_poll_callback(self.user_stopped, user, server_name)
             finally:
@@ -460,7 +656,8 @@ class BaseHandler(RequestHandler):
 
         # hook up spawner._spawn_future so that other requests can await
         # this result
-        finish_spawn_future = spawner._spawn_future = finish_user_spawn()
+        finish_spawn_future = spawner._spawn_future = maybe_future(finish_user_spawn())
+
         def _clear_spawn_future(f):
             # clear spawner._spawn_future when it's done
             # keep an exception around, though, to prevent repeated implicit spawns
@@ -469,10 +666,44 @@ class BaseHandler(RequestHandler):
                 spawner._spawn_future = None
             # Now we're all done. clear _spawn_pending flag
             spawner._spawn_pending = False
+
         finish_spawn_future.add_done_callback(_clear_spawn_future)
 
+        # when spawn finishes (success or failure)
+        # update failure count and abort if consecutive failure limit
+        # is reached
+        def _track_failure_count(f):
+            if f.exception() is None:
+                # spawn succeeded, reset failure count
+                self.settings['failure_count'] = 0
+                return
+            # spawn failed, increment count and abort if limit reached
+            self.settings.setdefault('failure_count', 0)
+            self.settings['failure_count'] += 1
+            failure_count = self.settings['failure_count']
+            failure_limit = spawner.consecutive_failure_limit
+            if failure_limit and 1 < failure_count < failure_limit:
+                self.log.warning(
+                    "%i consecutive spawns failed.  "
+                    "Hub will exit if failure count reaches %i before succeeding",
+                    failure_count, failure_limit,
+                )
+            if failure_limit and failure_count >= failure_limit:
+                self.log.critical(
+                    "Aborting due to %i consecutive spawn failures", failure_count
+                )
+                # abort in 2 seconds to allow pending handlers to resolve
+                # mostly propagating errors for the current failures
+                def abort():
+                    raise SystemExit(1)
+                IOLoop.current().call_later(2, abort)
+
+        finish_spawn_future.add_done_callback(_track_failure_count)
+
         try:
-            yield gen.with_timeout(timedelta(seconds=self.slow_spawn_timeout), finish_spawn_future)
+            await gen.with_timeout(
+                timedelta(seconds=self.slow_spawn_timeout), finish_spawn_future
+            )
         except gen.TimeoutError:
             # waiting_for_response indicates server process has started,
             # but is yet to become responsive.
@@ -485,10 +716,13 @@ class BaseHandler(RequestHandler):
 
             # start has finished, but the server hasn't come up
             # check if the server died while we were waiting
-            status = yield spawner.poll()
+            status = await spawner.poll()
             if status is not None:
                 toc = IOLoop.current().time()
                 self.statsd.timing('spawner.failure', (toc - tic) * 1000)
+                SERVER_SPAWN_DURATION_SECONDS.labels(
+                    status=ServerSpawnStatus.failure
+                ).observe(time.perf_counter() - spawn_start_time)
                 raise web.HTTPError(500, "Spawner failed to start [status=%s]. The logs for %s may contain details." % (
                     status, spawner._log_name))
 
@@ -506,21 +740,19 @@ class BaseHandler(RequestHandler):
                 self.log.warning("User %s is slow to be added to the proxy (timeout=%s)",
                                  user_server_name, self.slow_spawn_timeout)
 
-    @gen.coroutine
+    async def user_stopped(self, user, server_name):
-    def user_stopped(self, user, server_name):
         """Callback that fires when the spawner has stopped"""
         spawner = user.spawners[server_name]
-        status = yield spawner.poll()
+        status = await spawner.poll()
         if status is None:
             status = 'unknown'
         self.log.warning("User %s server stopped, with exit code: %s",
             user.name, status,
         )
-        yield self.proxy.delete_user(user, server_name)
+        await self.proxy.delete_user(user, server_name)
-        yield user.stop(server_name)
+        await user.stop(server_name)
 
-    @gen.coroutine
+    async def stop_single_user(self, user, name=''):
-    def stop_single_user(self, user, name=''):
         if name not in user.spawners:
             raise KeyError("User %s has no such spawner %r", user.name, name)
         spawner = user.spawners[name]
@@ -530,8 +762,7 @@ class BaseHandler(RequestHandler):
         # to avoid races
         spawner._stop_pending = True
 
-        @gen.coroutine
+        async def stop():
-        def stop():
             """Stop the server
 
             1. remove it from the proxy
@@ -540,8 +771,8 @@ class BaseHandler(RequestHandler):
             """
             tic = IOLoop.current().time()
             try:
-                yield self.proxy.delete_user(user, name)
+                await self.proxy.delete_user(user, name)
-                yield user.stop(name)
+                await user.stop(name)
             finally:
                 spawner._stop_pending = False
             toc = IOLoop.current().time()
@@ -549,13 +780,10 @@ class BaseHandler(RequestHandler):
             self.statsd.timing('spawner.stop', (toc - tic) * 1000)
 
         try:
-            yield gen.with_timeout(timedelta(seconds=self.slow_stop_timeout), stop())
+            await gen.with_timeout(timedelta(seconds=self.slow_stop_timeout), stop())
         except gen.TimeoutError:
-            if spawner._stop_pending:
+            # hit timeout, but stop is still pending
-                # hit timeout, but stop is still pending
+            self.log.warning("User %s:%s server is slow to stop", user.name, name)
-                self.log.warning("User %s:%s server is slow to stop", user.name, name)
-            else:
-                raise
 
     #---------------------------------------------------------------
     # template rendering
@@ -579,14 +807,16 @@ class BaseHandler(RequestHandler):
         return self.settings['jinja2_env'].get_template(name)
 
     def render_template(self, name, **ns):
-        ns.update(self.template_namespace)
+        template_ns = {}
+        template_ns.update(self.template_namespace)
+        template_ns.update(ns)
         template = self.get_template(name)
-        return template.render(**ns)
+        return template.render(**template_ns)
 
     @property
     def template_namespace(self):
         user = self.get_current_user()
-        return dict(
+        ns = dict(
             base_url=self.hub.base_url,
             prefix=self.base_url,
             user=user,
@@ -596,6 +826,9 @@ class BaseHandler(RequestHandler):
             static_url=self.static_url,
             version_hash=self.version_hash,
         )
+        if self.settings['template_vars']:
+            ns.update(self.settings['template_vars'])
+        return ns
 
     def write_error(self, status_code, **kwargs):
         """render custom error pages"""
@@ -616,6 +849,10 @@ class BaseHandler(RequestHandler):
             if reason:
                 message = reasons.get(reason, reason)
 
+        if exception and isinstance(exception, SQLAlchemyError):
+            self.log.warning("Rolling back session due to database error %s", exception)
+            self.db.rollback()
+
         # build template namespace
         ns = dict(
             status_code=status_code,
@@ -626,12 +863,27 @@ class BaseHandler(RequestHandler):
         )
 
         self.set_header('Content-Type', 'text/html')
+        if isinstance(exception, web.HTTPError):
+            # allow setting headers from exceptions
+            # since exception handler clears headers
+            headers = getattr(exception, 'headers', None)
+            if headers:
+                for key, value in headers.items():
+                    self.set_header(key, value)
+            # Content-Length must be recalculated.
+            self.clear_header('Content-Length')
+
         # render the template
         try:
             html = self.render_template('%s.html' % status_code, **ns)
         except TemplateNotFound:
             self.log.debug("No template for %d", status_code)
-            html = self.render_template('error.html', **ns)
+            try:
+                html = self.render_template('error.html', **ns)
+            except:
+                # In this case, any side effect must be avoided.
+                ns['no_spawner_check'] = True
+                html = self.render_template('error.html', **ns)
 
         self.write(html)
 
@@ -649,6 +901,11 @@ class PrefixRedirectHandler(BaseHandler):
     """
     def get(self):
         uri = self.request.uri
+        # Since self.base_url will end with trailing slash.
+        # Ensure uri will end with trailing slash when matching
+        # with self.base_url.
+        if not uri.endswith('/'):
+            uri += '/'
         if uri.startswith(self.base_url):
             path = self.request.uri[len(self.base_url):]
         else:
@@ -668,13 +925,46 @@ class UserSpawnHandler(BaseHandler):
     which will in turn send her to /user/alice/notebooks/mynotebook.ipynb.
     """
 
-    @gen.coroutine
+    def _fail_api_request(self, user):
-    def get(self, name, user_path):
+        """Fail an API request to a not-running server"""
+        self.set_status(404)
+        self.set_header("Content-Type", "application/json")
+        self.write(json.dumps({"message": "%s is not running" % user.name}))
+        self.finish()
+
+    async def get(self, name, user_path):
         if not user_path:
             user_path = '/'
         current_user = self.get_current_user()
+        if (
+            current_user
+            and current_user.name != name
+            and current_user.admin
+            and self.settings.get('admin_access', False)
+        ):
+            # allow admins to spawn on behalf of users
+            user = self.find_user(name)
+            if user is None:
+                # no such user
+                raise web.HTTPError(404, "No such user %s" % name)
+            self.log.info("Admin %s requesting spawn on behalf of %s",
+                          current_user.name, user.name)
+            admin_spawn = True
+            should_spawn = True
+        else:
+            user = current_user
+            admin_spawn = False
+            # For non-admins, we should spawn if the user matches
+            # otherwise redirect users to their own server
+            should_spawn = (current_user and current_user.name == name)
 
-        if current_user and current_user.name == name:
+        if "api" in user_path.split("/") and not user.active:
+            # API request for not-running server (e.g. notebook UI left open)
+            # Avoid triggering a spawn.
+            self._fail_api_request(user)
+            return
+
+        if should_spawn:
             # if spawning fails for any reason, point users to /hub/home to retry
             self.extra_error_html = self.spawn_home_error
 
@@ -693,8 +983,8 @@ class UserSpawnHandler(BaseHandler):
                     Make sure to connect to the proxied public URL %s
                     """, self.request.full_url(), self.proxy.public_url)
 
-            # logged in as correct user, check for pending spawn
+            # logged in as valid user, check for pending spawn
-            spawner = current_user.spawner
+            spawner = user.spawner
 
             # First, check for previous failure.
             if (
@@ -713,51 +1003,70 @@ class UserSpawnHandler(BaseHandler):
                 raise copy.copy(exc).with_traceback(exc.__traceback__)
 
             # check for pending spawn
-            if spawner.pending and spawner._spawn_future:
+            if spawner.pending == 'spawn' and spawner._spawn_future:
                 # wait on the pending spawn
                 self.log.debug("Waiting for %s pending %s", spawner._log_name, spawner.pending)
                 try:
-                    yield gen.with_timeout(timedelta(seconds=self.slow_spawn_timeout), spawner._spawn_future)
+                    await gen.with_timeout(timedelta(seconds=self.slow_spawn_timeout), spawner._spawn_future)
                 except gen.TimeoutError:
                     self.log.info("Pending spawn for %s didn't finish in %.1f seconds", spawner._log_name, self.slow_spawn_timeout)
                     pass
 
             # we may have waited above, check pending again:
+            # page could be pending spawn *or* stop
             if spawner.pending:
                 self.log.info("%s is pending %s", spawner._log_name, spawner.pending)
                 # spawn has started, but not finished
                 self.statsd.incr('redirects.user_spawn_pending', 1)
-                html = self.render_template("spawn_pending.html", user=current_user)
+                url_parts = []
+                if spawner.pending == "stop":
+                    page = "stop_pending.html"
+                else:
+                    page = "spawn_pending.html"
+                html = self.render_template(
+                    page,
+                    user=user,
+                    spawner=spawner,
+                    progress_url=spawner._progress_url,
+                )
                 self.finish(html)
                 return
 
             # spawn has supposedly finished, check on the status
             if spawner.ready:
-                status = yield spawner.poll()
+                status = await spawner.poll()
             else:
                 status = 0
 
             # server is not running, trigger spawn
             if status is not None:
                 if spawner.options_form:
-                    self.redirect(url_concat(url_path_join(self.hub.base_url, 'spawn'),
+                    url_parts = [self.hub.base_url, 'spawn']
+                    if current_user.name != user.name:
+                        # spawning on behalf of another user
+                        url_parts.append(user.name)
+                    self.redirect(url_concat(url_path_join(*url_parts),
                                              {'next': self.request.uri}))
                     return
                 else:
-                    yield self.spawn_single_user(current_user)
+                    await self.spawn_single_user(user)
 
             # spawn didn't finish, show pending page
             if spawner.pending:
                 self.log.info("%s is pending %s", spawner._log_name, spawner.pending)
                 # spawn has started, but not finished
                 self.statsd.incr('redirects.user_spawn_pending', 1)
-                html = self.render_template("spawn_pending.html", user=current_user)
+                html = self.render_template(
+                    "spawn_pending.html",
+                    user=user,
+                    progress_url=spawner._progress_url,
+                )
                 self.finish(html)
                 return
 
             # We do exponential backoff here - since otherwise we can get stuck in a redirect loop!
             # This is important in many distributed proxy implementations - those are often eventually
-            # consistent and can take upto a couple of seconds to actually apply throughout the cluster.
+            # consistent and can take up to a couple of seconds to actually apply throughout the cluster.
             try:
                 redirects = int(self.get_argument('redirects', 0))
             except ValueError:
@@ -782,18 +1091,16 @@ class UserSpawnHandler(BaseHandler):
                     )
                 raise web.HTTPError(500, msg)
 
-            # set login cookie anew
-            self.set_login_cookie(current_user)
             without_prefix = self.request.uri[len(self.hub.base_url):]
             target = url_path_join(self.base_url, without_prefix)
             if self.subdomain_host:
-                target = current_user.host + target
+                target = user.host + target
 
             # record redirect count in query parameter
             if redirects:
                 self.log.warning("Redirect loop detected on %s", self.request.uri)
                 # add capped exponential backoff where cap is 10s
-                yield gen.sleep(min(1 * (2 ** redirects), 10))
+                await gen.sleep(min(1 * (2 ** redirects), 10))
                 # rewrite target url with new `redirects` query value
                 url_parts = urlparse(target)
                 query_parts = parse_qs(url_parts.query)
@@ -809,6 +1116,9 @@ class UserSpawnHandler(BaseHandler):
             # logged in as a different user, redirect
             self.statsd.incr('redirects.user_to_user', 1)
             target = url_path_join(current_user.url, user_path or '')
+            if self.request.query:
+                # FIXME: use urlunparse instead?
+                target += '?' + self.request.query
             self.redirect(target)
         else:
             # not logged in, clear any cookies and reload
@@ -862,6 +1172,7 @@ class AddSlashHandler(BaseHandler):
         self.redirect(urlunparse(dest))
 
 default_handlers = [
+    (r'', AddSlashHandler),  # add trailing / to `/hub`
     (r'/user/([^/]+)(/.*)?', UserSpawnHandler),
     (r'/user-redirect/(.*)?', UserRedirectHandler),
     (r'/security/csp-report', CSPReportHandler),

jupyterhub/handlers/login.py

@@ -42,8 +42,7 @@ class LoginHandler(BaseHandler):
                 ),
         )
 
-    @gen.coroutine
+    async def get(self):
-    def get(self):
         self.statsd.incr('login.request')
         user = self.get_current_user()
         if user:
@@ -58,7 +57,7 @@ class LoginHandler(BaseHandler):
                     # auto_login without a custom login handler
                     # means that auth info is already in the request
                     # (e.g. REMOTE_USER header)
-                    user = yield self.login_user()
+                    user = await self.login_user()
                     if user is None:
                         # auto_login failed, just 403
                         raise web.HTTPError(403)
@@ -72,27 +71,20 @@ class LoginHandler(BaseHandler):
             username = self.get_argument('username', default='')
             self.finish(self._render(username=username))
 
-    @gen.coroutine
+    async def post(self):
-    def post(self):
         # parse the arguments dict
         data = {}
         for arg in self.request.arguments:
             data[arg] = self.get_argument(arg, strip=False)
 
         auth_timer = self.statsd.timer('login.authenticate').start()
-        user = yield self.login_user(data)
+        user = await self.login_user(data)
         auth_timer.stop(send=False)
 
         if user:
-            already_running = False
+            # register current user for subsequent requests to user (e.g. logging the request)
-            if user.spawner.ready:
+            self.get_current_user = lambda: user
-                status = yield user.spawner.poll()
+            self.redirect(self.get_next_url(user))
-                already_running = (status is None)
-            if not already_running and not user.spawner.options_form \
-                    and not user.spawner.pending:
-                # logging in triggers spawn
-                yield self.spawn_single_user(user)
-            self.redirect(self.get_next_url())
         else:
             html = self._render(
                 login_error='Invalid username or password',

jupyterhub/handlers/metrics.py

@@ -0,0 +1,16 @@
+from prometheus_client import REGISTRY, CONTENT_TYPE_LATEST, generate_latest
+from tornado import gen
+
+from .base import BaseHandler
+
+class MetricsHandler(BaseHandler):
+    """
+    Handler to serve Prometheus metrics
+    """
+    async def get(self):
+        self.set_header('Content-Type', CONTENT_TYPE_LATEST)
+        self.write(generate_latest(REGISTRY))
+
+default_handlers = [
+    (r'/metrics$', MetricsHandler)
+]