Error handling for missing locked task.

pybossa/sched.py

@@ -792,9 +792,17 @@ def get_task_id_and_duration_for_project_user(project_id, user_id):
     max_seconds_remaining = float('-inf')
     for task_id, task_project_id in zip(user_task_ids, project_ids):
         if not task_project_id:
-            task_project_id = task_repo.get_task(task_id).project_id
-            save_task_id_project_id(task_id, task_project_id, 2 * TIMEOUT)
-        if int(task_project_id) == project_id:
+            task = task_repo.get_task(task_id)
+            if task:
+                task_project_id = task.project_id
+                save_task_id_project_id(task_id, task_project_id, 2 * TIMEOUT)
+            else:
+                # No task found for task_id.
+                current_app.logger.info(
+                    "Project {}, User {}, Task Id {} - task not found in get_task_id_and_duration_for_project_user()."
+                    .format(project_id, user_id, task_id))
+
+        if task_project_id and int(task_project_id) == project_id:
             seconds_remaining = LockManager.seconds_remaining(user_tasks[task_id])
             if seconds_remaining > max_seconds_remaining:
                 max_seconds_task_id = int(task_id)

test/test_locked_sched.py

@@ -296,6 +296,24 @@ def test_get_task_id_and_duration_for_project_user_missing(self):
         assert get_task_id_project_id_key(task.id).encode() in sentinel.master.keys()
         assert task.id == task_id
 
+    @with_context
+    @patch('pybossa.sched.task_repo.get_task')
+    def test_get_task_id_and_duration_for_project_user_invalid_task_id(self, get_task):
+        user = UserFactory.create()
+        project = ProjectFactory.create(owner=user, short_name='egil', name='egil',
+                  description='egil')
+        task = TaskFactory.create_batch(1, project=project, n_answers=1)[0]
+        limit = 1
+        timeout = 100
+        acquire_locks(task.id, user.id, limit, timeout)
+
+        # Simulate invalid task.
+        get_task.return_value =  None
+        task_id, seconds = get_task_id_and_duration_for_project_user(project.id, user.id)
+
+        assert task_id is None
+        assert seconds == -1
+
     @with_context
     def test_tasks_assigned_as_per_user_access_levels_l1(self):
         """ Test tasks assigned by locked scheduler are as per access levels set for user, task and project"""