Add a gallery JupyterHub service

tljh-voila-gallery/setup.py

@@ -7,5 +7,12 @@
         "console_scripts": ["build-gallery-images = tljh_voila_gallery.build_images:main"]
     },
     packages=find_packages(),
-    include_package_data=True
+    include_package_data=True,
+    install_requires=[
+        # These get installed into the hub environment
+        'dockerspawner',
+        'jupyter-repo2docker',
+        'binderhub',
+        'nullauthenticator'
+    ]
 )

tljh-voila-gallery/tljh_voila_gallery/__init__.py

@@ -1,4 +1,5 @@
 import socket
+import sys
 import os
 import jinja2
 from pkg_resources import resource_stream, resource_filename
@@ -29,26 +30,41 @@ def options_form(spawner):
 
 @hookimpl
 def tljh_custom_jupyterhub_config(c):
-    # Since dockerspawner isn't available at import time
     from dockerspawner import DockerSpawner
+    from nullauthenticator import NullAuthenticator
     class GallerySpawner(DockerSpawner):
-        def options_from_form(self, formdata):
-            options = {}
-            if 'example' in formdata:
-                options['example'] = formdata['example'][0]
-            return options
+        # FIXME: What to do about idle culling?!
+        cmd = 'jupyter-notebook'
+
+        events = False
+
+        def get_args(self):
+            args = [
+                '--ip=0.0.0.0',
+                '--port=%i' % self.port,
+                '--NotebookApp.base_url=%s' % self.server.base_url,
+                '--NotebookApp.token=%s' % self.user_options['token'],
+                '--NotebookApp.trust_xheaders=True',
+            ]
+            return args + self.args
 
         def start(self):
-            gallery = get_gallery()
-            examples = gallery['examples']
-            chosen_example = self.user_options['example']
-            assert chosen_example in examples
-            self.default_url = examples[chosen_example]['url']
-            self.image = examples[chosen_example]['image']
+            if 'token' not in self.user_options:
+                raise web.HTTPError(400, "token required")
+            if 'image' not in self.user_options:
+                raise web.HTTPError(400, "image required")
+            self.image = self.user_options['image']
             return super().start()
 
+
+    class GalleryAuthenticator(NullAuthenticator):
+        auto_login = True
+
+        def login_url(self, base_url):
+            return '/services/gallery'
+
     c.JupyterHub.spawner_class = GallerySpawner
-    c.JupyterHub.authenticator_class = 'tmpauthenticator.TmpAuthenticator'
+    c.JupyterHub.authenticator_class = GalleryAuthenticator
 
     c.JupyterHub.hub_connect_ip = socket.gethostname()
 
@@ -57,23 +73,15 @@ def start(self):
 
     # rm containers when they stop
     c.DockerSpawner.remove = True
-    # Disabled until we fix it in TmpAuthenticator
-    # c.TmpAuthenticator.force_new_server = True
-
-    c.DockerSpawner.cmd = ['jupyterhub-singleuser']
 
-    # Override JupyterHub template
-    c.JupyterHub.template_paths = [TEMPLATES_PATH]
-
-    c.Spawner.options_form = options_form
-
-
-@hookimpl
-def tljh_extra_hub_pip_packages():
-    return [
-        'dockerspawner',
-        'git+https://github.com/jupyter/repo2docker.git@f19e159dfe1006dbd82c7728e15cdd19751e8aec'
-    ]
+    c.JupyterHub.services = [{
+        'name': 'gallery',
+        'admin': True,
+        'url': 'http://127.0.0.1:9888',
+        'command': [
+            sys.executable, '-m', 'tljh_voila_gallery.gallery'
+        ]
+    }]
 
 @hookimpl
 def tljh_extra_apt_packages():

tljh-voila-gallery/tljh_voila_gallery/gallery.py

@@ -0,0 +1,62 @@
+import os
+from tornado import ioloop, web
+from pkg_resources import resource_stream, resource_filename
+from ruamel.yaml import YAML
+from jinja2 import PackageLoader, Environment
+import json
+from binderhub.launcher import Launcher
+from urllib.parse import urljoin, urlencode
+
+yaml = YAML()
+
+# Read gallery.yaml on each spawn. If this gets too expensive, cache it here
+def get_gallery():
+    with resource_stream(__name__, 'gallery.yaml') as f:
+        return yaml.load(f)
+
+templates = Environment(loader=PackageLoader('tljh_voila_gallery', 'templates'))
+
+class GalleryHandler(web.RequestHandler):
+    def get(self):
+        gallery_template = templates.get_template('gallery-examples.html')
+        gallery = get_gallery()
+
+        self.write(gallery_template.render(
+            url=self.request.full_url(),
+            examples=gallery.get('examples', [])
+        ))
+
+    async def post(self):
+        gallery = get_gallery()
+
+        example_name = self.get_body_argument('example')
+
+        example = gallery['examples'][example_name]
+
+
+        launcher = Launcher(
+            hub_api_token=os.environ['JUPYTERHUB_API_TOKEN'],
+            hub_url=os.environ['JUPYTERHUB_BASE_URL']
+        )
+        response = await launcher.launch(
+            example['image'],
+            launcher.unique_name_from_repo(example['repo_url'])
+        )
+        redirect_url = urljoin(
+            response['url'],
+            example['url']
+        ) +  '?' + urlencode({'token': response['token']})
+        self.redirect(redirect_url)
+
+
+def make_app():
+    return web.Application([
+        (os.environ['JUPYTERHUB_SERVICE_PREFIX'] + '/?', GalleryHandler),
+    ])
+
+if __name__ == "__main__":
+    if not os.environ['JUPYTERHUB_API_URL'].endswith('/'):
+        os.environ['JUPYTERHUB_API_URL'] = os.environ['JUPYTERHUB_API_URL'] + '/'
+    app = make_app()
+    app.listen(9888)
+    ioloop.IOLoop.current().start()

tljh-voila-gallery/tljh_voila_gallery/gallery.yaml

@@ -3,20 +3,20 @@ examples:
     title: country-indicators
     description: Explore the correlations between indicators of development using matplotlib and ipywidgets
     image: country-indicators:latest
-    url: /voila/render/index.ipynb
+    url: voila/render/index.ipynb
     repo_url: https://github.com/voila-gallery/voila-gallery-country-indicators
     image_url: https://i.imgur.com/IeG75O3.png
   gaussian-density:
     title: gaussian-density
     description: Explore the normal distribution interactively with bqplot
     image: gaussian-density:latest
-    url: /voila/render/index.ipynb
+    url: voila/render/index.ipynb
     repo_url: https://github.com/voila-gallery/gaussian-density
     image_url: https://i.imgur.com/J1Mj6rc.png
   render-stl:
     title: render-stl
     description: Explore STL files with ipyvolume
     image: render-stl:latest
-    url: /voila/render/index.ipynb
+    url: voila/render/index.ipynb
     repo_url: https://github.com/voila-gallery/render-stl
     image_url: https://github.com/voila-gallery/render-stl/raw/master/thumbnail.png

tljh-voila-gallery/tljh_voila_gallery/templates/options_form.html → tljh-voila-gallery/tljh_voila_gallery/templates/gallery-examples.html

@@ -1,3 +1,7 @@
+{% extends "page.html" %}
+
+{% block body %}
+        <form enctype="multipart/form-data" id="spawn_form" action="{{url}}" method="post" role="form">
 <div class="row">
 {% for example_name, info in examples.items() %}
         <div class="col-md-4">
@@ -18,3 +22,7 @@ <h4>{{ info.title }}</h4>
         </div>
 {% endfor %}
 </div>
+
+        </form>
+
+{% endblock %}

tljh-voila-gallery/tljh_voila_gallery/templates/spawn.html → tljh-voila-gallery/tljh_voila_gallery/templates/page.html

@@ -81,10 +81,8 @@ <h1 class="jumbotron-heading">Voila Dashboards Gallery</h1>
 
   <div class="album py-5 bg-light">
     <div class="container">
-
-        <form enctype="multipart/form-data" id="spawn_form" action="{{url}}" method="post" role="form">
-           {{spawner_options_form | safe}}
-        </form>
+      {% block body %}
+      {% endblock %}
     </div>
   </div>