Added notifications documentation page

In this changeset, I added a new Sphinx directive (from Nova) that
allows us to automatically display notification samples for of
all the upcoming notifications in Watcher.

Partially Implements: blueprint watcher-notifications-ovo

Change-Id: Id7d819ee21db6dc616c78faea483b883f77e3bd6

doc/ext/versioned_notifications.py

@@ -0,0 +1,133 @@
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+"""
+This provides a sphinx extension able to list the implemented versioned
+notifications into the developer documentation.
+
+It is used via a single directive in the .rst file
+
+  .. versioned_notifications::
+
+"""
+
+from sphinx.util.compat import Directive
+from docutils import nodes
+
+from watcher.objects.notifications import base as notification
+from watcher.objects import base
+
+
+class VersionedNotificationDirective(Directive):
+
+    SAMPLE_ROOT = 'doc/notification_samples/'
+    TOGGLE_SCRIPT = """
+<script>
+jQuery(document).ready(function(){
+    jQuery('#%s-div').toggle('show');
+    jQuery('#%s-hideshow').on('click', function(event) {
+        jQuery('#%s-div').toggle('show');
+    });
+});
+</script>
+"""
+
+    def run(self):
+        notifications = self._collect_notifications()
+        return self._build_markup(notifications)
+
+    def _collect_notifications(self):
+        base.WatcherObjectRegistry.register_notification_objects()
+        notifications = []
+        ovos = base.WatcherObjectRegistry.obj_classes()
+        for name, cls in ovos.items():
+            cls = cls[0]
+            if (issubclass(cls, notification.NotificationBase) and
+                    cls != notification.NotificationBase):
+
+                payload_name = cls.fields['payload'].objname
+                payload_cls = ovos[payload_name][0]
+                for sample in cls.samples:
+                    notifications.append((cls.__name__,
+                                          payload_cls.__name__,
+                                          sample))
+        return sorted(notifications)
+
+    def _build_markup(self, notifications):
+        content = []
+        cols = ['Event type', 'Notification class', 'Payload class', 'Sample']
+        table = nodes.table()
+        content.append(table)
+        group = nodes.tgroup(cols=len(cols))
+        table.append(group)
+
+        head = nodes.thead()
+        group.append(head)
+
+        for _ in cols:
+            group.append(nodes.colspec(colwidth=1))
+
+        body = nodes.tbody()
+        group.append(body)
+
+        # fill the table header
+        row = nodes.row()
+        body.append(row)
+        for col_name in cols:
+            col = nodes.entry()
+            row.append(col)
+            text = nodes.strong(text=col_name)
+            col.append(text)
+
+        # fill the table content, one notification per row
+        for name, payload, sample_file in notifications:
+            event_type = sample_file[0: -5].replace('-', '.')
+
+            row = nodes.row()
+            body.append(row)
+            col = nodes.entry()
+            row.append(col)
+            text = nodes.literal(text=event_type)
+            col.append(text)
+
+            col = nodes.entry()
+            row.append(col)
+            text = nodes.literal(text=name)
+            col.append(text)
+
+            col = nodes.entry()
+            row.append(col)
+            text = nodes.literal(text=payload)
+            col.append(text)
+
+            col = nodes.entry()
+            row.append(col)
+
+            with open(self.SAMPLE_ROOT + sample_file, 'r') as f:
+                sample_content = f.read()
+
+            event_type = sample_file[0: -5]
+            html_str = self.TOGGLE_SCRIPT % ((event_type, ) * 3)
+            html_str += ("<input type='button' id='%s-hideshow' "
+                         "value='hide/show sample'>" % event_type)
+            html_str += ("<div id='%s-div'><pre>%s</pre></div>"
+                         % (event_type, sample_content))
+
+            raw = nodes.raw('', html_str, format="html")
+            col.append(raw)
+
+        return content
+
+
+def setup(app):
+    app.add_directive('versioned_notifications',
+                      VersionedNotificationDirective)

doc/source/conf.py

@@ -12,8 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import sys
 import os
+import sys
 
 from watcher import version as watcher_version
 from watcher import objects
@@ -41,6 +41,7 @@ extensions = [
     'stevedore.sphinxext',
     'wsmeext.sphinxext',
     'ext.term',
+    'ext.versioned_notifications',
 ]
 
 wsme_protocols = ['restjson']

doc/source/dev/notifications.rst

@@ -0,0 +1,13 @@
+..
+      Except where otherwise noted, this document is licensed under Creative
+      Commons Attribution 3.0 License.  You can view the license at:
+
+          https://creativecommons.org/licenses/by/3.0/
+
+.. _watcher_notifications:
+
+========================
+Notifications in Watcher
+========================
+
+.. versioned_notifications::

doc/source/index.rst

@@ -56,6 +56,7 @@ Getting Started
   dev/devstack
   deploy/configuration
   deploy/conf-files
+  dev/notifications
   dev/testing
   dev/rally_link
 

watcher/objects/notifications/exception.py

@@ -43,6 +43,7 @@ class ExceptionPayload(notificationbase.NotificationPayloadBase):
             exception_message=six.text_type(fault))
 
 
+@notificationbase.notification_sample('infra-optim-exception.json')
 @base.WatcherObjectRegistry.register_notification
 class ExceptionNotification(notificationbase.NotificationBase):
     # Version 1.0: Initial version