only return the parent id of all pending tasks

inventory_provider/routes/jobs.py

@@ -32,16 +32,16 @@ def update():
                 status=503,
                 mimetype="text/html")
 
-    job_ids = worker.launch_refresh_cache_all(
+    phase2_task_id = worker.launch_refresh_cache_all(
         current_app.config["INVENTORY_PROVIDER_CONFIG"])
-    return jsonify(job_ids)
+    return jsonify({'task id': phase2_task_id})
 
 
 @routes.route("reload-router-config/<equipment_name>", methods=['GET', 'POST'])
 @common.require_accepts_json
 def reload_router_config(equipment_name):
     result = worker.reload_router_config.delay(equipment_name)
-    return jsonify([result.id])
+    return jsonify({'task id': result.id})
 
 
 @routes.route("check-task-status/<task_id>", methods=['GET', 'POST'])

inventory_provider/tasks/worker.py

@@ -512,6 +512,29 @@ def _erase_next_db(config):
             new_next=saved_latch['next'])
 
 
+@app.task(base=InventoryTask, bind=True, name='internal_refresh_phase_2')
+@log_task_entry_and_exit
+def internal_refresh_phase_2(self):
+    # second batch of subtasks:
+    #   alarms db status cache
+    #   juniper netconf & snmp data
+    subtasks = [
+        update_equipment_locations.apply_async(),
+        update_lg_routers.apply_async(),
+        update_access_services.apply_async(),
+        import_unmanaged_interfaces.apply_async()
+    ]
+    for hostname in data.derive_router_hostnames(config):
+        logger.debug('queueing router refresh jobs for %r' % hostname)
+        subtasks.append(reload_router_config.apply_async(args=[hostname]))
+
+    pending_task_ids = [x.id for x in subtasks]
+
+    t = refresh_finalizer.apply_async(args=[json.dumps(pending_task_ids)])
+    pending_task_ids.append(t.id)
+    return pending_task_ids
+
+
 def launch_refresh_cache_all(config):
     """
     utility function intended to be called outside of the worker process
@@ -531,24 +554,10 @@ def launch_refresh_cache_all(config):
     ]
     [x.get() for x in subtasks]
 
-    # second batch of subtasks:
-    #   alarms db status cache
-    #   juniper netconf & snmp data
-    subtasks = [
-        update_equipment_locations.apply_async(),
-        update_lg_routers.apply_async(),
-        update_access_services.apply_async(),
-        import_unmanaged_interfaces.apply_async()
-    ]
-    for hostname in data.derive_router_hostnames(config):
-        logger.debug('queueing router refresh jobs for %r' % hostname)
-        subtasks.append(reload_router_config.apply_async(args=[hostname]))
-
-    pending_task_ids = [x.id for x in subtasks]
-
-    t = refresh_finalizer.apply_async(args=[json.dumps(pending_task_ids)])
-    pending_task_ids.append(t.id)
-    return pending_task_ids
+    # now launch the task whose only purpose is to
+    # act as a convenient parent for all of the remaining tasks
+    t = internal_refresh_phase_2.apply_async()
+    return t.id
 
 
 def _wait_for_tasks(task_ids, update_callback=lambda s: None):
@@ -679,14 +688,13 @@ def check_task_status(task_id):
         'ready': r.status in states.READY_STATES,
         'success': r.status == states.SUCCESS,
     }
-    if r.result:
-        # TODO: only discovered this case by testing, is this the only one?
-        #       ... otherwise need to pre-test json serialization
-        if isinstance(r.result, Exception):
-            result['result'] = {
-                'error type': type(r.result).__name__,
-                'message': str(r.result)
-            }
-        else:
-            result['result'] = r.result
+    # TODO: only discovered this case by testing, is this the only one?
+    #       ... otherwise need to pre-test json serialization
+    if isinstance(r.result, Exception):
+        result['result'] = {
+            'error type': type(r.result).__name__,
+            'message': str(r.result)
+        }
+    else:
+        result['result'] = r.result
     return result