Consolidated subscription logic, switched to managed session.

This patch takes all the helper methods from subscriptions_handler.py
and places them into the actual worker task. Furthermore, the
subscription worker now uses a self-managed session.

Change-Id: I1a68c92bc68dc0a1f0bf713ee43d0d2a74332c17

storyboard/notifications/subscriptions_handler.py

@@ -1,112 +0,0 @@
-# Copyright (c) 2014 Hewlett-Packard Development Company, L.P.
-#
-# 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.
-
-import json
-
-from storyboard.db.api import comments as comments_api
-from storyboard.db.api import stories as story_api
-from storyboard.db.api import subscription_events as sub_events_api
-from storyboard.db.api import subscriptions as subscriptions_api
-from storyboard.db.api import timeline_events as timeline_api
-
-
-def handle_timeline_events(event, author_id, subscribers):
-
-    for user_id in subscribers:
-        if event.event_type == 'user_comment':
-            event_info = resolve_comments(event)
-
-        else:
-            event_info = event.event_info
-
-        sub_events_api.subscription_events_create({
-            "author_id": author_id,
-            "subscriber_id": user_id,
-            "event_type": event.event_type,
-            "event_info": event_info
-        })
-
-
-def handle_resources(method, resource_id, sub_resource_id, author_id,
-                     subscribers):
-
-    if sub_resource_id:
-
-        for user_id in subscribers:
-
-            if method == 'DELETE':
-                event_type = 'project removed from project_group'
-                event_info = json.dumps({'project_group_id': resource_id,
-                                         'project_id': sub_resource_id})
-
-            else:
-                event_type = 'project added to project_group'
-                event_info = json.dumps({'project_group_id': resource_id,
-                                         'project_id': sub_resource_id})
-
-            sub_events_api.subscription_events_create({
-                "author_id": author_id,
-                "subscriber_id": user_id,
-                "event_type": event_type,
-                "event_info": event_info
-            })
-
-    else:
-        if method == 'DELETE':
-            # Handling project_group targeted.
-            for user_id in subscribers:
-                sub_events_api.subscription_events_create({
-                    "author_id": author_id,
-                    "subscriber_id": user_id,
-                    "event_type": 'project_group deleted',
-                    "event_info": json.dumps({'project_group_id': resource_id})
-                })
-
-
-def handle_deletions(resource_name, resource_id):
-    target_subs = []
-    sub_ids = set()
-    resource_name = resource_name[:-1]
-
-    target_sub = subscriptions_api.subscription_get_all_by_target(
-        resource_name, resource_id)
-    target_subs.extend(target_sub)
-
-    for sub in target_subs:
-        sub_ids.add(sub.id)
-
-    for sub_id in sub_ids:
-        subscriptions_api.subscription_delete(sub_id)
-
-
-def resolve_comments(event):
-    event_info = {
-        'comment_id': event.comment_id or None,
-    }
-
-    # Retrieve the content of the comment.
-    comment = comments_api.comment_get(event.comment_id)
-    event_info['comment_content'] = comment.content
-
-    # Retrieve the story ID of the comment.
-    timeline_events = timeline_api.events_get_all(comment_id=event.comment_id)
-    if timeline_events:
-        story = story_api.story_get(timeline_events[0].story_id)
-
-        if story:
-            event_info['story_id'] = story.id
-            event_info['story_title'] = story.title
-
-    return json.dumps(event_info)

storyboard/worker/task/subscription.py

@@ -12,16 +12,22 @@
 # implied. See the License for the specific language governing permissions and
 # limitations under the License.
 
-from storyboard.db.api import subscriptions
+import json
-from storyboard.db.api import timeline_events
+
-from storyboard.notifications.subscriptions_handler import handle_deletions
+import storyboard.db.api.base as db_api
-from storyboard.notifications.subscriptions_handler import handle_resources
+from storyboard.db.api import subscriptions as sub_api
-from storyboard.notifications.subscriptions_handler import \
+import storyboard.db.models as models
-    handle_timeline_events
 from storyboard.worker.task.base import WorkerTaskBase
 
 
 class Subscription(WorkerTaskBase):
+    def enabled(self):
+        """This plugin is always enabled.
+
+        :return: True
+        """
+        return True
+
     def handle(self, author_id, method, path, status, resource, resource_id,
                sub_resource=None, sub_resource_id=None,
                resource_before=None, resource_after=None):
@@ -39,26 +45,139 @@ class Subscription(WorkerTaskBase):
         :param resource_before: The resource state before this event occurred.
         :param resource_after: The resource state after this event occurred.
         """
+        session = db_api.get_session(in_request=False, autocommit=False)
 
+        try:
             if resource == 'timeline_event':
-            event = timeline_events.event_get(resource_id)
+                event = db_api.entity_get(models.TimeLineEvent, resource_id,
-            subscribers = subscriptions.subscription_get_all_subscriber_ids(
+                                          session=session)
-                'story', event.story_id
+                subscribers = sub_api.subscription_get_all_subscriber_ids(
-            )
+                    'story', event.story_id, session=session)
-            handle_timeline_events(event, author_id, subscribers)
+                self.handle_timeline_events(session, event, author_id,
+                                            subscribers)
 
             elif resource == 'project_group':
-            subscribers = subscriptions.subscription_get_all_subscriber_ids(
+                subscribers = sub_api.subscription_get_all_subscriber_ids(
-                resource, resource_id
+                    resource, resource_id, session=session)
-            )
+                self.handle_resources(session=session,
-            handle_resources(method=method,
+                                      method=method,
                                       resource_id=resource_id,
                                       sub_resource_id=sub_resource_id,
                                       author_id=author_id,
                                       subscribers=subscribers)
 
             if method == 'DELETE' and not sub_resource_id:
-            handle_deletions(resource, resource_id)
+                self.handle_deletions(session, resource, resource_id)
 
-    def enabled(self):
+            session.commit()
-        return True
+            session.flush()
+        except Exception:
+            session.rollback()
+
+    def handle_deletions(self, session, resource_name, resource_id):
+        target_subs = []
+        sub_ids = set()
+        resource_name = resource_name[:-1]
+
+        target_sub = db_api.entity_get_all(models.Subscription,
+                                           target_type=resource_name,
+                                           target_id=resource_id,
+                                           session=session)
+        target_subs.extend(target_sub)
+
+        for sub in target_subs:
+            sub_ids.add(sub.id)
+
+        for sub_id in sub_ids:
+            db_api.entity_hard_delete(models.Subscription,
+                                      sub_id,
+                                      session=session)
+
+    def handle_timeline_events(self, session, event, author_id, subscribers):
+
+        for user_id in subscribers:
+            if event.event_type == 'user_comment':
+                event_info = json.dumps(
+                    self.resolve_comments(session=session, event=event)
+                )
+
+            else:
+                event_info = event.event_info
+
+            db_api.entity_create(models.SubscriptionEvents, {
+                "author_id": author_id,
+                "subscriber_id": user_id,
+                "event_type": event.event_type,
+                "event_info": event_info
+            }, session=session)
+
+    def handle_resources(self, session, method, resource_id, sub_resource_id,
+                         author_id, subscribers):
+
+        if sub_resource_id:
+
+            for user_id in subscribers:
+
+                if method == 'DELETE':
+                    event_type = 'project removed from project_group'
+                    event_info = json.dumps({'project_group_id': resource_id,
+                                             'project_id': sub_resource_id})
+
+                else:
+                    event_type = 'project added to project_group'
+                    event_info = json.dumps({'project_group_id': resource_id,
+                                             'project_id': sub_resource_id})
+
+                db_api.entity_create(models.SubscriptionEvents, {
+                    "author_id": author_id,
+                    "subscriber_id": user_id,
+                    "event_type": event_type,
+                    "event_info": event_info
+                }, session=session)
+
+        else:
+            if method == 'DELETE':
+                # Handling project_group targeted.
+                for user_id in subscribers:
+                    db_api.entity_create(models.SubscriptionEvents, {
+                        "author_id": author_id,
+                        "subscriber_id": user_id,
+                        "event_type": 'project_group deleted',
+                        "event_info": json.dumps(
+                            {'project_group_id': resource_id})
+                    }, session=session)
+
+    def resolve_comments(self, session, event):
+
+        # Sanity check. If there's no comment_id, exit.
+        if 'comment_id' not in event:
+            return None
+
+        # Retrieve the content of the comment.
+        comment = db_api.entity_get(models.Comment,
+                                    event.comment_id,
+                                    session=session)
+        if not comment:
+            return None
+
+        # Retrieve the timeline events.
+        timeline_event = session.query(models.TimeLineEvent) \
+            .filter(models.TimeLineEvent.comment_id == event.comment_id) \
+            .first()
+        if not timeline_event:
+            return None
+
+        # Retrieve the story from the timeline event.
+        story = db_api.entity_get(models.Story,
+                                  timeline_event.story_id,
+                                  session=session)
+        if not story:
+            return None
+
+        # Construct and return the comment's event_info object.
+        return {
+            'comment_id': comment.id,
+            'comment_content': comment.content,
+            'story_id': story.id,
+            'story_title': story.title
+        }