Rainy Day Tasks

A pretty inaccurate and incomplete version of Google Cloud Tasks for local development. If you are using App Engine HTTP requests, you must create a file called hosts.json to map your projects to local URLs, like:

{
    "projects/my-project-id/locations/europe-west2/queues/my-queue-name": {
        "host": "http://localhost:8002",
        "retry_limit": 3
    }
}

Example

The server will accept the same payload that you would usually pass to the CloudTasksClient, like so:

def create_task(url, queue='default', payload=None, countdown=None):
    """
    Create a task for a given queue with an arbitrary payload.
          url : relative url to tasks handler in this project
        queue : string name of the target queue
      payload : json payload
    countdown : number of seconds until the task should execute
    """
    client = tasks_v2.CloudTasksClient()

    project = settings.PROJECT_ID
    location = settings.PROJECT_LOCATION

    parent = client.queue_path(project, location, queue)
    task = {
        'app_engine_http_request': {
            'http_method': 'POST',
            'relative_uri': url
        }
    }
    if payload is not None:
        if not isinstance(payload, str):
            payload = json.dumps(payload, cls=DjangoJSONEncoder)
        converted_payload = payload.encode()
        task['app_engine_http_request']['body'] = converted_payload

    if countdown is not None:
        target_time = datetime.datetime.utcnow() + datetime.timedelta(seconds=countdown)
        timestamp = timestamp_pb2.Timestamp()
        timestamp.FromDatetime(target_time)
        task['schedule_time'] = timestamp

    if os.getenv('GAE_APPLICATION'):
        response = client.create_task(parent, task)
        logging.info('Created task %r', response.name)
    else:
        try:
            logging.info("Create task on local rainy day server")
            logging.info(task)
            task['app_engine_http_request']['body'] = payload
            response = requests.post(
                f"http://localhost:8500/?parent={parent}",
                json=task)
        except requests.exceptions.ConnectionError:
            logging.info("Connection error contacting rainy day server, "
                         "local server probably not running")
            response = None
        else:
            print(response.status_code)
    return response