migrated to asynchronous tasks for staggering user and users playlist execution

requirements.txt

@@ -3,11 +3,12 @@ certifi==2019.6.16
 chardet==3.0.4
 Click==7.0
 Flask==1.1.1
-google-api-core==1.14.0
+google-api-core==1.14.2
 google-auth==1.6.3
-google-cloud-core==1.0.2
-google-cloud-firestore==1.3.0
+google-cloud-core==1.0.3
+google-cloud-firestore==1.4.0
 google-cloud-pubsub==0.45.0
+google-cloud-tasks==1.2.0
 googleapis-common-protos==1.6.0
 grpc-google-iam-v1==0.12.3
 grpcio==1.22.0
@@ -15,10 +16,10 @@ idna==2.8
 itsdangerous==1.1.0
 Jinja2==2.10.1
 MarkupSafe==1.1.1
-protobuf==3.9.0
-pyasn1==0.4.5
-pyasn1-modules==0.2.5
-pytz==2019.1
+protobuf==3.9.1
+pyasn1==0.4.6
+pyasn1-modules==0.2.6
+pytz==2019.2
 requests==2.22.0
 rsa==4.0
 six==1.12.0

spotify/api/api.py

@@ -1,6 +1,12 @@
 from flask import Blueprint, session, request, jsonify
+
+import datetime
+import json
+
 from google.cloud import firestore
 from google.cloud import pubsub_v1
+from google.cloud import tasks_v2
+from google.protobuf import timestamp_pb2
 from werkzeug.security import check_password_hash, generate_password_hash
 
 import spotify.api.database as database
@@ -8,6 +14,9 @@ import spotify.api.database as database
 blueprint = Blueprint('api', __name__)
 db = firestore.Client()
 publisher = pubsub_v1.PublisherClient()
+tasker = tasks_v2.CloudTasksClient()
+
+task_path = tasker.queue_path('sarsooxyz', 'europe-west2', 'spotify-executions')
 
 run_playlist_topic_path = publisher.topic_path('sarsooxyz', 'run_user_playlist')
 
@@ -309,6 +318,19 @@ def run_playlist():
         return jsonify({'error': 'not logged in'}), 401
 
 
+@blueprint.route('/playlist/run/task', methods=['POST'])
+def run_playlist_task():
+
+    if request.headers.get('X-AppEngine-QueueName', None):
+        payload = request.get_data(as_text=True)
+        if payload:
+            payload = json.loads(payload)
+            execute_playlist(payload['username'], payload['name'])
+            return jsonify({'message': 'executed playlist', 'status': 'success'}), 200
+    else:
+        return jsonify({'error': 'unauthorized'}), 401
+
+
 @blueprint.route('/playlist/run/user', methods=['GET'])
 def run_user():
 
@@ -327,6 +349,18 @@ def run_user():
         return jsonify({'error': 'not logged in'}), 401
 
 
+@blueprint.route('/playlist/run/user/task', methods=['POST'])
+def run_user_task():
+
+    if request.headers.get('X-AppEngine-QueueName', None):
+        payload = request.get_data(as_text=True)
+        if payload:
+            execute_user(payload)
+            return jsonify({'message': 'executed user', 'status': 'success'}), 200
+    else:
+        return jsonify({'error': 'unauthorized'}), 401
+
+
 @blueprint.route('/playlist/run/users', methods=['GET'])
 def run_users():
 
@@ -355,10 +389,32 @@ def run_users_cron():
 
 def execute_all_users():
 
+    seconds_delay = 0
+
     for iter_user in [i.to_dict() for i in db.collection(u'spotify_users').stream()]:
 
         if iter_user['spotify_linked'] and not iter_user['locked']:
-            execute_user(iter_user['username'])
+
+            task = {
+                'app_engine_http_request': {  # Specify the type of request.
+                    'http_method': 'POST',
+                    'relative_uri': '/api/playlist/run/user/task',
+                    'body': iter_user['username'].encode()
+                }
+            }
+
+            d = datetime.datetime.utcnow() + datetime.timedelta(seconds=seconds_delay)
+
+            # Create Timestamp protobuf.
+            timestamp = timestamp_pb2.Timestamp()
+            timestamp.FromDatetime(d)
+
+            # Add the timestamp to the tasks.
+            task['schedule_time'] = timestamp
+
+            tasker.create_task(task_path, task)
+
+            seconds_delay += 30
 
 
 def execute_user(username):
@@ -366,10 +422,37 @@ def execute_user(username):
     playlists = [i.to_dict() for i in
                  database.get_user_playlists_collection(database.get_user_query_stream(username)[0].id).stream()]
 
+    seconds_delay = 0
+
     for iterate_playlist in playlists:
         if len(iterate_playlist['parts']) > 0 or len(iterate_playlist['playlist_references']) > 0:
             if iterate_playlist.get('playlist_id', None):
-                execute_playlist(username, iterate_playlist['name'])
+
+                task = {
+                    'app_engine_http_request': {  # Specify the type of request.
+                        'http_method': 'POST',
+                        'relative_uri': '/api/playlist/run/task',
+                        'body': json.dumps({
+                            'username': username,
+                            'name': iterate_playlist['name']
+                        }).encode()
+                    }
+                }
+
+                d = datetime.datetime.utcnow() + datetime.timedelta(seconds=seconds_delay)
+
+                # Create Timestamp protobuf.
+                timestamp = timestamp_pb2.Timestamp()
+                timestamp.FromDatetime(d)
+
+                # Add the timestamp to the tasks.
+                task['schedule_time'] = timestamp
+
+                tasker.create_task(task_path, task)
+
+                seconds_delay += 10
+
+                # execute_playlist(username, iterate_playlist['name'])
 
 
 def execute_playlist(username, name):