From b72af1c1b99d0563ca501ac7175c82faff3790ba Mon Sep 17 00:00:00 2001
From: Steven Silvester <steven.silvester@ieee.org>
Date: Wed, 7 Sep 2016 06:20:38 -0500
Subject: [PATCH] Add some of the labextension pieces

---
 jupyterlab/__init__.py | 24 ++++++++++++++++--------
 jupyterlab/labapp.py   | 12 +++++++++++-
 setup.py               |  1 +
 3 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/jupyterlab/__init__.py b/jupyterlab/__init__.py
index c760f9806d87..45efe54d65a5 100644
--- a/jupyterlab/__init__.py
+++ b/jupyterlab/__init__.py
@@ -9,7 +9,6 @@
 from jinja2 import FileSystemLoader
 from notebook.utils import url_path_join as ujoin
 
-
 #-----------------------------------------------------------------------------
 # Module globals
 #-----------------------------------------------------------------------------
@@ -19,9 +18,9 @@
 
     npm run watch
 
-from the JupyterLab repo directory in another terminal window to have the system
-incrementally watch and build JupyterLab's TypeScript for you, as you make
-changes.
+from the JupyterLab repo directory in another terminal window to have the 
+system incrementally watch and build JupyterLab's TypeScript for you, as you 
+make changes.
 """
 
 HERE = os.path.dirname(__file__)
@@ -54,9 +53,10 @@ def get_template(self, name):
 
 default_handlers = [
     (PREFIX + r'/?', LabHandler),
-    (PREFIX+r"/(.+)", FileFindHandler,
+    (PREFIX + r"/(.*)", FileFindHandler,
         {'path': BUILT_FILES}),
-    ]
+]
+
 
 def _jupyter_server_extension_paths():
     return [{
@@ -69,7 +69,15 @@ def load_jupyter_server_extension(nbapp):
     dev_mode = os.path.exists(os.path.join(base_dir, '.git'))
     if dev_mode:
         nbapp.log.info(DEV_NOTE_NPM)
-    nbapp.log.info('JupyterLab alpha preview extension loaded from %s'%HERE)
+    nbapp.log.info('JupyterLab alpha preview extension loaded from %s' % HERE)
     webapp = nbapp.web_app
     base_url = webapp.settings['base_url']
-    webapp.add_handlers(".*$", [(ujoin(base_url, h[0]),) + h[1:] for h in default_handlers])
+    webapp.add_handlers(".*$",
+        [(ujoin(base_url, h[0]),) + h[1:] for h in default_handlers])
+    lab_extension_handler = (
+        r"/labextensions/(.*)", FileFindHandler, {
+            'path': nbapp.labextensions_path,
+            'no_cache_paths': ['/'],  # don't cache anything in labbextensions
+        }
+    )
+    webapp.add_handlers(".*$", [lab_extension_handler])
diff --git a/jupyterlab/labapp.py b/jupyterlab/labapp.py
index 5a52171b2bf3..53d652f8f4c7 100644
--- a/jupyterlab/labapp.py
+++ b/jupyterlab/labapp.py
@@ -5,8 +5,9 @@
 # Distributed under the terms of the Modified BSD License.
 
 # TODO: import base server app
+from jupyter_core.paths import jupyter_path
 from notebook.notebookapp import NotebookApp
-from traitlets import Unicode
+from traitlets import List, Unicode
 
 
 class LabApp(NotebookApp):
@@ -15,6 +16,15 @@ class LabApp(NotebookApp):
         help="The default URL to redirect to from `/`"
     )
 
+    extra_labextensions_path = List(Unicode(), config=True,
+        help="""extra paths to look for JupyterLab extensions"""
+    )
+
+    @property
+    def labextensions_path(self):
+        """The path to look for JupyterLab extensions"""
+        return self.extra_labextensions_path + jupyter_path('labextensions')
+
 #-----------------------------------------------------------------------------
 # Main entry point
 #-----------------------------------------------------------------------------
diff --git a/setup.py b/setup.py
index 87a95cdf8caa..c4656006870d 100644
--- a/setup.py
+++ b/setup.py
@@ -154,6 +154,7 @@ def run(self):
     'entry_points': {
         'console_scripts': [
             'jupyter-lab = jupyterlab.labapp:main',
+            'jupyter-labextension = jupyterlab.labextensions:main',
         ]
     },
     'author': 'Jupyter Development Team',