Refactoring gcloud workers to initialize a subscriber and publisher c…

…lient for each worker

experiment/measurer/measure_manager.py

@@ -915,7 +915,7 @@ def initialize_queues(self, manager) -> Tuple[Optional[str], Optional[str]]:
     def _create_response_queue_subscription(self):
         """Creates a new Pub/Sub subscription for the response queue."""
         try:
-            subscription = self.subscriber_client.create_subscription(
+            subscription = pubsub_v1.SubscriberClient().create_subscription(
                 request={
                     'name': self.subscription_path,
                     'topic': self.response_queue_topic_path
@@ -929,14 +929,6 @@ def _create_response_queue_subscription(self):
 
     def start_workers(self, request_queue, response_queue, pool):
         self._create_response_queue_subscription()
-        config = {
-            'request_queue_topic_id': self.request_queue_topic_id,
-            'response_queue_topic_id': self.response_queue_topic_id,
-            'region_coverage': self.region_coverage,
-            'project_id': self.project_id,
-            'experiment': self.experiment,
-        }
-        google_cloud_worker = measure_worker.GoogleCloudMeasureWorker(config)
 
         # Since each worker is going to be in an infinite loop, we dont need
         # result return. Workers' life scope will end automatically when
@@ -946,7 +938,29 @@ def start_workers(self, request_queue, response_queue, pool):
                        f'{self.measurers_cpus}'
                        ' workers in google cloud measure manager')
         logger.info(log_message)
+
+        config = {
+            'request_queue_topic_id': self.request_queue_topic_id,
+            'response_queue_topic_id': self.response_queue_topic_id,
+            'region_coverage': self.region_coverage,
+            'project_id': self.project_id,
+            'experiment': self.experiment,
+        }
+
+        # Create the worker request queue subscription once, before starting all
+        # workers
+        worker_request_queue_subscription = ('request-queue-subscription-'
+                                             f'{self.experiment}')
+        worker_subscription_path = self.subscriber_client.subscription_path(
+            self.project_id, worker_request_queue_subscription)
+        worker_request_queue_topic_path = self.subscriber_client.topic_path(
+            self.project_id, self.request_queue_topic_id)
+        measure_worker.GoogleCloudMeasureWorker.create_request_queue_subscription(  # pylint: disable=line-too-long
+            worker_subscription_path, worker_request_queue_topic_path)
+
         for _ in range(self.measurers_cpus):
+            google_cloud_worker = measure_worker.GoogleCloudMeasureWorker(
+                config)
             pool.apply_async(google_cloud_worker.measure_worker_loop)
 
     def get_result_from_response_queue(self, response_queue: str):

experiment/measurer/measure_worker.py

@@ -145,15 +145,16 @@ def __init__(self, config: Dict):
                                            f'{self.experiment}')
         self.subscription_path = self.subscriber_client.subscription_path(
             self.project_id, self.request_queue_subscription)
-        self._create_request_queue_subscription()
 
-    def _create_request_queue_subscription(self):
+    @staticmethod
+    def create_request_queue_subscription(subscription_path,
+                                          request_queue_topic_path):
         """Creates a new Pub/Sub subscription for the request queue."""
         try:
-            subscription = self.subscriber_client.create_subscription(
+            subscription = pubsub_v1.SubscriberClient().create_subscription(
                 request={
-                    'name': self.subscription_path,
-                    'topic': self.request_queue_topic_path,
+                    'name': subscription_path,
+                    'topic': request_queue_topic_path,
                     'enable_message_ordering': True,
                 })
             logger.info('Subscription %s created successfully.',

experiment/measurer/test_measure_manager.py

@@ -659,7 +659,10 @@ def test_gcloud_measure_manager_get_snapshot_from_response_queue(
 
 
 @mock.patch('experiment.measurer.measure_worker.GoogleCloudMeasureWorker')
-def test_gcloud_measure_manager_start_workers(mock_gcloud_measure_worker,
+@mock.patch('google.cloud.pubsub_v1.PublisherClient')
+@mock.patch('google.cloud.pubsub_v1.SubscriberClient')
+def test_gcloud_measure_manager_start_workers(_mock_subscriber, _mock_publisher,
+                                              mock_gcloud_measure_worker,
                                               gcloud_measure_manager):
     """Tests that the start workers method is calling the measure worker loop
     method, a number of times equal to the number of measurers CPUs."""