remove dependency on IPython

- Standalone traitlets has been released, use it directly.
- Copy url_path_join from notebook

jupyterhub/app.py

@@ -31,15 +31,11 @@ from tornado.ioloop import IOLoop, PeriodicCallback
 from tornado.log import app_log, access_log, gen_log
 from tornado import gen, web
 
-import IPython
-if V(IPython.__version__) < V('3.0'):
-    raise ImportError("JupyterHub Requires IPython >= 3.0, found %s" % IPython.__version__)
-
-from IPython.utils.traitlets import (
+from traitlets import (
     Unicode, Integer, Dict, TraitError, List, Bool, Any,
     Type, Set, Instance, Bytes, Float,
 )
-from IPython.config import Application, catch_config_error
+from traitlets.config import Application, catch_config_error
 
 here = os.path.dirname(__file__)
 

jupyterhub/auth.py

@@ -10,8 +10,8 @@ from subprocess import check_call, check_output, CalledProcessError
 from tornado import gen
 import simplepam
 
-from IPython.config import LoggingConfigurable
-from IPython.utils.traitlets import Bool, Set, Unicode, Any
+from traitlets.config import LoggingConfigurable
+from traitlets import Bool, Set, Unicode, Any
 
 from .handlers.login import LoginHandler
 from .utils import url_path_join

jupyterhub/singleuser.py

@@ -17,7 +17,7 @@ from jinja2 import ChoiceLoader, FunctionLoader
 from tornado import ioloop
 from tornado.web import HTTPError
 
-from IPython.utils.traitlets import (
+from traitlets import (
     Integer,
     Unicode,
     CUnicode,

jupyterhub/spawner.py

@@ -16,8 +16,8 @@ from tempfile import TemporaryDirectory
 from tornado import gen
 from tornado.ioloop import IOLoop, PeriodicCallback
 
-from IPython.config import LoggingConfigurable
-from IPython.utils.traitlets import (
+from traitlets.config import LoggingConfigurable
+from traitlets import (
     Any, Bool, Dict, Enum, Instance, Integer, Float, List, Unicode,
 )
 

jupyterhub/tests/test_traitlets.py

@@ -1,7 +1,4 @@
-try:
 from traitlets import HasTraits
-except ImportError:
-    from IPython.utils.traitlets import HasTraits
 
 from jupyterhub.traitlets import URLPrefix, Command
 

jupyterhub/traitlets.py

@@ -2,7 +2,7 @@
 # Copyright (c) Jupyter Development Team.
 # Distributed under the terms of the Modified BSD License.
 
-from IPython.utils.traitlets import List, Unicode
+from traitlets import List, Unicode
 
 class URLPrefix(Unicode):
     def validate(self, obj, value):

jupyterhub/utils.py

@@ -14,11 +14,6 @@ from tornado import web, gen, ioloop
 from tornado.httpclient import AsyncHTTPClient, HTTPError
 from tornado.log import app_log
 
-try:
-    from jupyter_notebook.utils import url_path_join
-except:
-    from IPython.html.utils import url_path_join
-
 
 def random_port():
     """get a single random port"""
@@ -174,3 +169,24 @@ def compare_token(compare, token):
     return False
 
 
+def url_path_join(*pieces):
+    """Join components of url into a relative url
+
+    Use to prevent double slash when joining subpath. This will leave the
+    initial and final / in place
+    
+    Copied from notebook.utils.url_path_join
+    """
+    initial = pieces[0].startswith('/')
+    final = pieces[-1].endswith('/')
+    stripped = [ s.strip('/') for s in pieces ]
+    result = '/'.join(s for s in stripped if s)
+
+    if initial:
+        result = '/' + result
+    if final:
+        result = result + '/'
+    if result == '//':
+        result = '/'
+
+    return result

requirements.txt

@@ -1,4 +1,4 @@
-ipython>=3
+traitlets>=4
 tornado>=4
 jinja2
 simplepam