| .. Licensed to the Apache Software Foundation (ASF) under one |
| or more contributor license agreements. See the NOTICE file |
| distributed with this work for additional information |
| regarding copyright ownership. The ASF licenses this file |
| to you 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. |
| |
| |
| |
| Google Cloud PubSub Operators |
| ============================= |
| |
| `Google Cloud PubSub <https://cloud.google.com/pubsub/>`__ is a fully-managed real-time |
| messaging service that allows you to send and receive messages between independent applications. |
| You can leverage Cloud Pub/Sub’s flexibility to decouple systems and components hosted |
| on Google Cloud or elsewhere on the Internet. |
| |
| Publisher applications can send messages to a topic and other applications can subscribe to that topic to receive the messages. |
| By decoupling senders and receivers Google Cloud PubSub allows developers to communicate between independently written applications. |
| |
| Prerequisite Tasks |
| ^^^^^^^^^^^^^^^^^^ |
| |
| .. include::/operators/_partials/prerequisite_tasks.rst |
| |
| .. _howto/operator:PubSubCreateTopicOperator: |
| |
| Creating a PubSub topic |
| ^^^^^^^^^^^^^^^^^^^^^^^ |
| |
| The PubSub topic is a named resource to which messages are sent by publishers. |
| The :class:`~airflow.providers.google.cloud.operators.pubsub.PubSubCreateTopicOperator` operator creates a topic. |
| |
| .. exampleinclude:: /../../airflow/providers/google/cloud/example_dags/example_pubsub.py |
| :language: python |
| :start-after: [START howto_operator_gcp_pubsub_create_topic] |
| :end-before: [END howto_operator_gcp_pubsub_create_topic] |
| |
| |
| .. _howto/operator:PubSubCreateSubscriptionOperator: |
| |
| Creating a PubSub subscription |
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ |
| |
| A ``Subscription`` is a named resource representing the stream of messages from a single, specific topic, |
| to be delivered to the subscribing application. |
| The :class:`~airflow.providers.google.cloud.operators.pubsub.PubSubCreateSubscriptionOperator` operator creates the subscription. |
| |
| .. exampleinclude:: /../../airflow/providers/google/cloud/example_dags/example_pubsub.py |
| :language: python |
| :start-after: [START howto_operator_gcp_pubsub_create_subscription] |
| :end-before: [END howto_operator_gcp_pubsub_create_subscription] |
| |
| |
| .. _howto/operator:PubSubPublishMessageOperator: |
| |
| Publishing PubSub messages |
| ^^^^^^^^^^^^^^^^^^^^^^^^^^ |
| |
| A ``Message`` is a combination of data and (optional) attributes that a publisher sends to a topic and is eventually delivered to subscribers. |
| The :class:`~airflow.providers.google.cloud.operators.pubsub.PubSubPublishMessageOperator` operator would publish messages. |
| |
| .. exampleinclude:: /../../airflow/providers/google/cloud/example_dags/example_pubsub.py |
| :language: python |
| :start-after: [START howto_operator_gcp_pubsub_publish] |
| :end-before: [END howto_operator_gcp_pubsub_publish] |
| |
| |
| .. _howto/operator:PubSubPullSensor: |
| |
| Pulling messages from a PubSub subscription |
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ |
| The :class:`~airflow.providers.google.cloud.sensors.pubsub.PubSubPullSensor` sensor pulls messages from a PubSub subscription |
| and pass them through XCom. |
| |
| .. exampleinclude:: /../../airflow/providers/google/cloud/example_dags/example_pubsub.py |
| :language: python |
| :start-after: [START howto_operator_gcp_pubsub_pull_message_with_sensor] |
| :end-before: [END howto_operator_gcp_pubsub_pull_message_with_sensor] |
| |
| .. exampleinclude:: /../../airflow/providers/google/cloud/example_dags/example_pubsub.py |
| :language: python |
| :start-after: [START howto_operator_gcp_pubsub_pull_message_with_operator] |
| :end-before: [END howto_operator_gcp_pubsub_pull_message_with_operator] |
| |
| To pull messages from XCom use the :class:`~airflow.operators.bash.BashOperator`. |
| |
| .. exampleinclude:: /../../airflow/providers/google/cloud/example_dags/example_pubsub.py |
| :language: python |
| :start-after: [START howto_operator_gcp_pubsub_pull_messages_result_cmd] |
| :end-before: [END howto_operator_gcp_pubsub_pull_messages_result_cmd] |
| |
| .. exampleinclude:: /../../airflow/providers/google/cloud/example_dags/example_pubsub.py |
| :language: python |
| :start-after: [START howto_operator_gcp_pubsub_pull_messages_result] |
| :end-before: [END howto_operator_gcp_pubsub_pull_messages_result] |
| |
| |
| .. _howto/operator:PubSubDeleteSubscriptionOperator: |
| |
| Deleting a PubSub subscription |
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ |
| |
| The :class:`~airflow.providers.google.cloud.operators.pubsub.PubSubDeleteSubscriptionOperator` operator deletes the subscription. |
| |
| .. exampleinclude:: /../../airflow/providers/google/cloud/example_dags/example_pubsub.py |
| :language: python |
| :start-after: [START howto_operator_gcp_pubsub_unsubscribe] |
| :end-before: [END howto_operator_gcp_pubsub_unsubscribe] |
| |
| |
| .. _howto/operator:PubSubDeleteTopicOperator: |
| |
| Deleting a PubSub topic |
| ^^^^^^^^^^^^^^^^^^^^^^^ |
| |
| The :class:`~airflow.providers.google.cloud.operators.pubsub.PubSubDeleteTopicOperator` operator deletes topic. |
| |
| .. exampleinclude:: /../../airflow/providers/google/cloud/example_dags/example_pubsub.py |
| :language: python |
| :start-after: [START howto_operator_gcp_pubsub_delete_topic] |
| :end-before: [END howto_operator_gcp_pubsub_delete_topic] |
| |
| |
| Reference |
| ^^^^^^^^^ |
| |
| For further information, look at: |
| |
| * `Client Library Documentation <https://googleapis.dev/python/pubsub/latest/index.html>`__ |
| * `Product Documentation <https://cloud.google.com/pubsub/docs/>`__ |