add link to project source in navigation sidebar

Change-Id: I841f0e63259d6b79c55b223c8e7266c8520a668d
Closes-Bug: #1426898

oslosphinx/__init__.py

@@ -13,6 +13,28 @@
 #    under the License.
 
 import os
+import subprocess
+import urlparse
+
+
+CGIT_BASE = 'http://git.openstack.org/cgit/'
+_cgit_link = None
+
+
+def _html_page_context(app, pagename, templatename, context, doctree):
+    global _cgit_link
+    if _cgit_link is None:
+        try:
+            git_remote = subprocess.check_output(
+                ['git', 'config', '--local', '--get', 'remote.origin.url']
+            )
+        except subprocess.CheckedProcessException:
+            _cgit_link = 'unknown'
+        else:
+            parsed = urlparse.urlparse(git_remote)
+            _cgit_link = CGIT_BASE + parsed.path.lstrip('/')
+    context['cgit_link'] = _cgit_link
+    return context
 
 
 def builder_inited(app):
@@ -33,6 +55,8 @@ def builder_inited(app):
     # the templates and theme.
     if hasattr(app.builder, 'init_templates'):
         app.builder.init_templates()
+    # Register our page context additions
+    app.connect('html-page-context', _html_page_context)
 
 
 def setup(app):

oslosphinx/theme/openstack/layout.html

@@ -30,6 +30,15 @@
                                   title="{{ _('next chapter') }}">{{ next.title }}</a></p>
           {%- endif %}
           {%- endblock %}
+          {%- block projectsource %}
+            {%- if cgit_link %}
+            <h3>{{ _('Project Source') }}</h3>
+            <ul class="this-page-menu">
+              <li><a href="{{cgit_link}}"
+                     rel="nofollow">{{ _('Project Source') }}</a></li>
+            </ul>
+            {%- endif %}
+          {%- endblock %}
           {%- block sidebarsourcelink %}
           {%- if show_source and has_source and sourcename %}
             <h3>{{ _('This Page') }}</h3>