Make additional handlers customizable

Author: krinsman

nbviewer/app.py

@@ -80,9 +80,14 @@ class NBViewer(Application):
     # Use this to insert custom configuration of handlers for NBViewer extensions
     handler_settings = Dict().tag(config=True)
 
+    create_handler      = Unicode(default_value="nbviewer.handlers.CreateHandler",                      help="The Tornado handler to use for creation via frontpage form.").tag(config=True)
+    custom404_handler   = Unicode(default_value="nbviewer.handlers.Custom404",                          help="The Tornado handler to use for rendering 404 templates.").tag(config=True)
+    faq_handler         = Unicode(default_value="nbviewer.handlers.FAQHandler",                         help="The Tornado handler to use for rendering and viewing the FAQ section.").tag(config=True)
     gist_handler        = Unicode(default_value="nbviewer.providers.gist.handlers.GistHandler",         help="The Tornado handler to use for viewing notebooks stored as GitHub Gists").tag(config=True)
     github_blob_handler = Unicode(default_value="nbviewer.providers.github.handlers.GitHubBlobHandler", help="The Tornado handler to use for viewing notebooks stored as blobs on GitHub").tag(config=True)
     github_tree_handler = Unicode(default_value="nbviewer.providers.github.handlers.GitHubTreeHandler", help="The Tornado handler to use for viewing directory trees on GitHub").tag(config=True)
+    github_user_handler = Unicode(default_value="nbviewer.providers.github.handlers.GitHubUserHandler", help="The Tornado handler to use for viewing all of a user's repositories on GitHub.").tag(config=True)
+    index_handler       = Unicode(default_value="nbviewer.handlers.IndexHandler",                       help="The Tornado handler to use for rendering the frontpage section.").tag(config=True)
     local_handler       = Unicode(default_value="nbviewer.providers.local.handlers.LocalFileHandler",   help="The Tornado handler to use for viewing notebooks found on a local filesystem").tag(config=True)
     url_handler         = Unicode(default_value="nbviewer.providers.url.handlers.URLHandler",           help="The Tornado handler to use for viewing notebooks accessed via URL").tag(config=True)
     user_gists_handler  = Unicode(default_value="nbviewer.providers.gist.handlers.UserGistsHandler",    help="The Tornado handler to use for viewing directory containing all of a user's Gists").tag(config=True)
@@ -239,9 +244,14 @@ def template_paths(self):
     def init_tornado_application(self):
         # handle handlers
         handler_names = dict(
+                  create_handler=self.create_handler,
+                  custom404_handler=self.custom404_handler,
+                  faq_handler=self.faq_handler,
                   gist_handler=self.gist_handler,
                   github_blob_handler=self.github_blob_handler,
                   github_tree_handler=self.github_tree_handler,
+                  github_user_handler=self.github_user_handler,
+                  index_handler=self.index_handler,
                   local_handler=self.local_handler,
                   url_handler=self.url_handler,
                   user_gists_handler=self.user_gists_handler,

nbviewer/handlers.py

@@ -12,6 +12,7 @@
 from .providers import (
     provider_handlers,
     provider_uri_rewrites,
+    _load_handler_from_location,
 )
 from .providers.base import (
     BaseHandler,
@@ -31,15 +32,19 @@ def prepare(self):
 
 class IndexHandler(BaseHandler):
     """Render the index"""
-    def get(self):
-        self.finish(self.render_template(
+
+    def render_index_template(self, **namespace):
+        return self.render_template(
             'index.html',
             title=self.frontpage_setup.get('title', None),
             subtitle=self.frontpage_setup.get('subtitle', None),
             text=self.frontpage_setup.get('text', None),
             show_input=self.frontpage_setup.get('show_input', True),
-            sections=self.frontpage_setup.get('sections', [])))
+            sections=self.frontpage_setup.get('sections', []),
+            **namespace)
 
+    def get(self):
+        self.finish(self.render_index_template())
 
 class FAQHandler(BaseHandler):
     """Render the markdown FAQ page"""
@@ -109,15 +114,23 @@ def init_handlers(formats, providers, base_url, localfiles, **handler_kwargs):
     but both it and `handler_names` to `provider_handlers`
     """
     handler_settings = handler_kwargs['handler_settings']
+    handler_names = handler_kwargs['handler_names']
+
+    create_handler = _load_handler_from_location(handler_names['create_handler'])
+    custom404_handler = _load_handler_from_location(handler_names['custom404_handler'])
+    faq_handler = _load_handler_from_location(handler_names['faq_handler'])
+    index_handler = _load_handler_from_location(handler_names['index_handler'])
 
+    # If requested endpoint matches multiple routes, it only gets handled by handler
+    # corresponding to the first matching route. So order of URLSpecs in this list matters.
     pre_providers = [
-        ('/?', IndexHandler, {}),
-        ('/index.html', IndexHandler, {}),
-        (r'/faq/?', FAQHandler, {}),
-        (r'/create/?', CreateHandler, {}),
+        ('/?', index_handler, {}),
+        ('/index.html', index_handler, {}),
+        (r'/faq/?', faq_handler, {}),
+        (r'/create/?', create_handler, {}),
 
         # don't let super old browsers request data-uris
-        (r'.*/data:.*;base64,.*', Custom404, {}),
+        (r'.*/data:.*;base64,.*', custom404_handler, {}),
     ]
 
     post_providers = [
@@ -144,6 +157,6 @@ def init_handlers(formats, providers, base_url, localfiles, **handler_kwargs):
         pattern = url_path_join(base_url, handler[0])
         new_handler = tuple([pattern] + list(handler[1:]))
         new_handlers.append(new_handler)
-    new_handlers.append((r'.*', Custom404, {}))
+    new_handlers.append((r'.*', custom404_handler, {}))
 
     return new_handlers

nbviewer/providers/github/handlers.py

@@ -109,6 +109,10 @@ def get(self, url):
 
 class GitHubUserHandler(GithubClientMixin, BaseHandler):
     """list a user's github repos"""
+    def render_github_user_template(self, entries, provider_url, next_url, prev_url, **namespace):
+        return self.render_template("userview.html", entries=entries, provider_url=provider_url,
+                    next_url=next_url, prev_url=prev_url, **self.PROVIDER_CTX, **namespace)
+
     @cached
     async def get(self, user):
         page = self.get_argument("page", None)
@@ -129,10 +133,9 @@ async def get(self, user):
             ))
 
         provider_url = u"{github_url}{user}".format(user=user, github_url=self.github_url)
-        html = self.render_template("userview.html",
+        html = self.render_github_user_template(
             entries=entries, provider_url=provider_url, 
             next_url=next_url, prev_url=prev_url,
-            **self.PROVIDER_CTX
         )
         await self.cache_and_finish(html)
 
@@ -164,7 +167,7 @@ def render_treelist_template(self, entries, breadcrumbs, provider_url, user, rep
                                     **self.PROVIDER_CTX, **namespace)
 
     @cached
-    async def get(self, user, repo, ref, path, **namespace):
+    async def get(self, user, repo, ref, path):
         if not self.request.uri.endswith('/'):
             self.redirect(self.request.uri + '/')
             return
@@ -260,8 +263,7 @@ async def get(self, user, repo, ref, path, **namespace):
         html = self.render_treelist_template(
              entries=entries, breadcrumbs=breadcrumbs, provider_url=provider_url,
              user=user, repo=repo, ref=ref, path=path, branches=branches, tags=tags,
-             executor_url=executor_url, **namespace 
-        )
+             executor_url=executor_url)
         await self.cache_and_finish(html)
 
     async def refs(self, user, repo):
@@ -389,6 +391,7 @@ def default_handlers(handlers=[], **handler_names):
 
     blob_handler = _load_handler_from_location(handler_names['github_blob_handler'])
     tree_handler = _load_handler_from_location(handler_names['github_tree_handler'])
+    user_handler = _load_handler_from_location(handler_names['github_user_handler'])
 
     return [
         # ideally these URIs should have been caught by an appropriate
@@ -401,7 +404,7 @@ def default_handlers(handlers=[], **handler_names):
         (r'/url[s]?/raw\.?githubusercontent\.com/(?P<user>[^\/]+)/(?P<repo>[^\/]+)/(?P<path>.*)', RawGitHubURLHandler, {}),
     ] + handlers + [
         (r'/github/([^\/]+)', AddSlashHandler, {}),
-        (r'/github/(?P<user>[^\/]+)/', GitHubUserHandler, {}),
+        (r'/github/(?P<user>[^\/]+)/', user_handler, {}),
         (r'/github/([^\/]+)/([^\/]+)', AddSlashHandler, {}),
         (r'/github/(?P<user>[^\/]+)/(?P<repo>[^\/]+)/', GitHubRepoHandler, {}),
         (r'/github/([^\/]+)/([^\/]+)/(?:blob|raw)/([^\/]+)/(.*)/', RemoveSlashHandler, {}),