pre-commit run -a

examples/service-fastapi/README.md

@@ -1,7 +1,6 @@
 # Fastapi
 
-[FastAPI](https://fastapi.tiangolo.com/) is a popular new web framework attractive for its type hinting, async support, automatic doc generation (Swagger), and more.  Their [Feature highlights](https://fastapi.tiangolo.com/features/) sum it up nicely.
-
+[FastAPI](https://fastapi.tiangolo.com/) is a popular new web framework attractive for its type hinting, async support, automatic doc generation (Swagger), and more. Their [Feature highlights](https://fastapi.tiangolo.com/features/) sum it up nicely.
 
 # Swagger UI with OAuth demo
 
@@ -18,7 +17,7 @@ jupyterhub --ip=127.0.0.1
 
 2. Visit http://127.0.0.1:8000/services/fastapi or http://127.0.0.1:8000/services/fastapi/docs
 
-3. Try interacting programmatically.  If you create a new token in your control panel or pull out the `JUPYTERHUB_API_TOKEN` in the single user environment, you can skip the third step here.  
+3. Try interacting programmatically. If you create a new token in your control panel or pull out the `JUPYTERHUB_API_TOKEN` in the single user environment, you can skip the third step here.
 
 ```
 $ curl -X GET http://127.0.0.1:8000/services/fastapi/
@@ -55,19 +54,19 @@ sudo docker build . -t service-fastapi
 sudo docker run -it -p 8000:8000 service-fastapi
 ```
 
-2. Visit http://127.0.0.1:8000/services/fastapi/docs.  When going through the OAuth flow or getting a token from the control panel, you can log in with `testuser` / `passwd`.
+2. Visit http://127.0.0.1:8000/services/fastapi/docs. When going through the OAuth flow or getting a token from the control panel, you can log in with `testuser` / `passwd`.
 
 # PUBLIC_HOST
 
-If you are running your service behind a proxy, or on a Docker / Kubernetes infrastructure, you might run into an error during OAuth that says `Mismatching redirect URI`.  In the Jupterhub logs, there will be a warning along the lines of: `[W 2021-04-06 23:40:06.707 JupyterHub provider:498] Redirect uri https://jupyterhub.my.cloud/services/fastapi/oauth_callback != /services/fastapi/oauth_callback`.  This happens because Swagger UI adds the request host, as seen in the browser, to the Authorization URL.
+If you are running your service behind a proxy, or on a Docker / Kubernetes infrastructure, you might run into an error during OAuth that says `Mismatching redirect URI`. In the Jupterhub logs, there will be a warning along the lines of: `[W 2021-04-06 23:40:06.707 JupyterHub provider:498] Redirect uri https://jupyterhub.my.cloud/services/fastapi/oauth_callback != /services/fastapi/oauth_callback`. This happens because Swagger UI adds the request host, as seen in the browser, to the Authorization URL.
 
-To solve that problem, the `oauth_redirect_uri` value in the service initialization needs to match what Swagger will auto-generate and what the service will use when POST'ing to `/oauth2/token`.  In this example, setting the `PUBLIC_HOST` environment variable to your public-facing Hub domain (e.g. `https://jupyterhub.my.cloud`) should make it work.
+To solve that problem, the `oauth_redirect_uri` value in the service initialization needs to match what Swagger will auto-generate and what the service will use when POST'ing to `/oauth2/token`. In this example, setting the `PUBLIC_HOST` environment variable to your public-facing Hub domain (e.g. `https://jupyterhub.my.cloud`) should make it work.
 
 # Notes on security.py
 
-FastAPI has a concept of a [dependency injection](https://fastapi.tiangolo.com/tutorial/dependencies) using a `Depends` object (and a subclass `Security`) that is automatically instantiated/executed when it is a parameter for your endpoint routes.  You can utilize a `Depends` object for re-useable common parameters or authentication mechanisms like the [`get_user`](https://fastapi.tiangolo.com/tutorial/security/get-current-user) pattern.
+FastAPI has a concept of a [dependency injection](https://fastapi.tiangolo.com/tutorial/dependencies) using a `Depends` object (and a subclass `Security`) that is automatically instantiated/executed when it is a parameter for your endpoint routes. You can utilize a `Depends` object for re-useable common parameters or authentication mechanisms like the [`get_user`](https://fastapi.tiangolo.com/tutorial/security/get-current-user) pattern.
 
-JupyterHub OAuth has three ways to authenticate: a `token` url parameter; a `Authorization: Bearer <token>` header; and a (deprecated) `jupyterhub-services` cookie.  FastAPI has helper functions that let us create `Security` (dependency injection) objects for each of those.  When you need to allow multiple / optional authentication dependencies (`Security` objects), then you can use the argument `auto_error=False` and it will return `None` instead of raising an `HTTPException`.
+JupyterHub OAuth has three ways to authenticate: a `token` url parameter; a `Authorization: Bearer <token>` header; and a (deprecated) `jupyterhub-services` cookie. FastAPI has helper functions that let us create `Security` (dependency injection) objects for each of those. When you need to allow multiple / optional authentication dependencies (`Security` objects), then you can use the argument `auto_error=False` and it will return `None` instead of raising an `HTTPException`.
 
 Endpoints that need authentication (`/me` and `/debug` in this example) can leverage the `get_user` pattern and effectively pull the user model from the Hub API when a request has authenticated with cookie / token / header all using the simple syntax,
 
@@ -83,7 +82,7 @@ async def new_endpoint(user: User = Depends(get_current_user)):
 
 # Notes on client.py
 
-FastAPI is designed to be an asynchronous web server, so the interactions with the Hub API should be made asynchronously as well.  Instead of using `requests` to get user information from a token/cookie, this example uses [`httpx`](https://www.python-httpx.org/).  `client.py` defines a small function that creates a `Client` (equivalent of `requests.Session`) with the Hub API url as it's `base_url` and adding the `JUPYTERHUB_API_TOKEN` to every header.
+FastAPI is designed to be an asynchronous web server, so the interactions with the Hub API should be made asynchronously as well. Instead of using `requests` to get user information from a token/cookie, this example uses [`httpx`](https://www.python-httpx.org/). `client.py` defines a small function that creates a `Client` (equivalent of `requests.Session`) with the Hub API url as it's `base_url` and adding the `JUPYTERHUB_API_TOKEN` to every header.
 
 ```python
 import os

examples/service-fastapi/app/models.py

@@ -1,5 +1,7 @@
 from datetime import datetime
-from typing import Any, List, Optional
+from typing import Any
+from typing import List
+from typing import Optional
 
 from pydantic import BaseModel