Add samples for Cloud Tasks

appengine/flexible/tasks/README.md

@@ -33,7 +33,7 @@ On Compute Engine and Container Engine, authentication credentials will be
 automatically detected, but the instances must have been created with the
 necessary scopes.
 
-In any other environment, for example Compute Engine instance without the
+In any other environment, for example a Compute Engine instance without the
 necessary scopes, you should set `GOOGLE_APPLICATION_CREDENTIALS` environment
 variable to a JSON key file for a service account.
 
@@ -42,17 +42,18 @@ for more information.
 
 ## Creating a queue
 
-To create a queue using the Cloud SDK, use the provided queue.yaml:
+To create a queue using the Cloud SDK, use the following gcloud command:
 
-    gcloud app deploy queue.yaml
+    gcloud alpha tasks queues create-app-engine-queue "my-appengine-queue"
 
-## Deploying the App Engine app
-
-First, vendor the dependencies into the project:
+Note: A newly created queue will route to the default App Engine service and
+version unless configured to do otherwise. Read the online help for the
+`create-app-engine-queue` or the `update-app-engine-queue` commands to learn
+about routing overrides for App Engine queues.
 
-    pip install -r requirements.txt
+## Deploying the App Engine app
 
-Next, deploy the App Engine app
+Deploy the App Engine app with gcloud:
 
     gcloud app deploy
 
@@ -61,47 +62,44 @@ Verify the index page is serving:
     gcloud app browse
 
 The App Engine app serves as a target for the push requests. It has an
-endpoint `/set_payload` that that stores the payload from the HTTP POST data in
-Cloud Datastore. The payload can be accessed in your browser at the
- `/get_payload` endpoint with a GET request.
+endpoint `/log_payload` that reads the payload (i.e., the request body) of the
+HTTP POST request and logs it. The log output can be viewed with:
+
+    gcloud app logs read
 
 ## Running the Samples
 
 The project ID must be specified either as a command line argument using
 `--project-id`, or by editing `DEFAULT_PROJECT_ID` within `task_snippets.py`.
 
-Set the environment variables:
+Set environment variables:
+
+First, your project ID:
 
     export PROJECT_ID=my-project-id
-    export LOCATION_ID=us-central1
-    export QUEUE_ID=my-appengine-queue # From queue.yaml
 
-View all queues:
+Then the queue ID, as specified at queue creation time. Queue IDs already
+created can be listed with `gcloud alpha tasks queue list`.
 
-     python app_engine_queue_snippets.py --api_key=$API_KEY list-queues --project_id=$PROJECT_ID --location_id=$LOCATION_ID
+    export QUEUE_ID=my-appengine-queue
 
-Set the queue name as an environment variable:
+And finally the location ID, which can be discovered with
+`gcloud alpha tasks queue describe $QUEUE_ID`, with the location embedded in the
+"name" value (for instance, if the name is
+"projects/my-project/locations/us-central1/queues/my-appengine-queue", then the
+location is "us-central1").
 
-    export QUEUE_NAME=projects/$PROJECT_ID/locations/$LOCATION_ID/queues/$QUEUE_ID
+    export LOCATION_ID=us-central1
 
 Create a task, targeted at the `set_payload` endpoint with a payload specified:
 
-   python app_engine_queue_snippets.py --api_key=$API_KEY create-task --queue_name=$QUEUE_NAME --payload=hello
-
-Now view that the payload was received and verify the count and payload:
-
-    http://your-app-id.appspot.com/get_payload
-
-Create a task that will be scheduled for a few seconds in the future using
-the `--in_seconds` flag:
-
-    python app_engine_queue_snippets.py --api_key=$API_KEY create-task --queue_name=$QUEUE_NAME --payload=hello --in_seconds=30
+   python create_app_engine_queue_task.py --project=$PROJECT_ID --queue=QUEUE_ID --location=LOCATION_ID --payload=hello
 
-Since `--in_seconds` was set to 30, it will take 30 seconds for the new
-payload to be pushed to the `/get_payload` endpoint, which can then be viewed at:
+Now view that the payload was received and verify the payload:
 
-    http://your-app-id.appspot.com/get_payload
+    gcloud app logs read
 
-It might also be helpful to view the request logs of your App Engine app:
+Create a task that will be scheduled for a time in the future using the
+`--in_seconds` flag:
 
-    https://console.cloud.google.com/logs
+    python create_app_engine_queue_task.py --project=$PROJECT_ID --queue=QUEUE_ID --location=LOCATION_ID --payload=hello --in_seconds=30

appengine/flexible/tasks/create_app_engine_queue_task.py

@@ -0,0 +1,112 @@
+# Copyright 2017 Google Inc. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from __future__ import print_function
+
+import argparse
+import base64
+import datetime
+import pprint
+
+from googleapiclient import discovery
+
+
+def seconds_from_now_to_rfc3339_datetime(seconds):
+    """Return an RFC 3339 datetime string for a number of seconds from now."""
+    d = datetime.datetime.utcnow() + datetime.timedelta(seconds=seconds)
+    return d.isoformat('T') + 'Z'
+
+
+def create_task(project, queue, location, payload=None, in_seconds=None):
+    """Create a task for a given queue with an arbitrary payload."""
+    client = get_client()
+
+    url = '/log_payload'
+    body = {
+        'task': {
+            'app_engine_task_target': {
+                'http_method': 'POST',
+                'relative_url': url
+            }
+        }
+    }
+
+    if payload is not None:
+        # Payload is a string (unicode), so 
+        body['task']['app_engine_task_target']['payload'] = base64.b64encode(
+            payload.encode()).decode()
+
+    if in_seconds is not None:
+        scheduled_time = seconds_from_now_to_rfc3339_datetime(in_seconds)
+        body['task']['schedule_time'] = scheduled_time
+
+    queue_name = 'projects/{}/locations/{}/queues/{}'.format(
+        project, location, queue)
+
+    print('Sending task {}'.format(pprint.pformat(body)))
+
+    response = client.projects().locations().queues().tasks().create(
+        parent=queue_name, body=body).execute()
+
+    # By default CreateTaskRequest.responseView is BASIC, so not all
+    # information is retrieved by default because some data, such as payloads,
+    # might be desirable to return only when needed because of its large size
+    # or because of the sensitivity of data that it contains.
+    print('Created task {}'.format(response['name']))
+    return response
+
+
+def get_client():
+    """Build an http client."""
+    DISCOVERY_URL = 'https://cloudtasks.googleapis.com/$discovery/rest?version=v2beta2'
+    client = discovery.build('cloudtasks', 'v2beta2',
+                             discoveryServiceUrl=DISCOVERY_URL)
+    return client
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(
+        description=create_task.__doc__,
+        formatter_class=argparse.RawDescriptionHelpFormatter)
+
+    parser.add_argument(
+        '--project',
+        help='Project of the queue to add the task to.'
+    )
+
+    parser.add_argument(
+        '--queue',
+        help='ID (short name) of the queue to add the task to.'
+    )
+
+    parser.add_argument(
+        '--location',
+        help='Location of the queue to add the task to.'
+    )
+
+    parser.add_argument(
+        '--payload',
+        help='Optional payload to attach to the push queue.'
+    )
+
+    parser.add_argument(
+        '--in_seconds',
+        help='The number of seconds from now to schedule task attempt.'
+    )
+
+    args = parser.parse_args()
+
+    create_task(
+        args.project, args.queue, args.location,
+        args.payload, args.in_seconds)