Source code for tests.system.providers.google.cloud.pubsub.example_pubsub

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"""
Example Airflow DAG that uses Google PubSub services.
"""
from __future__ import annotations

import os
from datetime import datetime

from airflow import models
from airflow.operators.bash import BashOperator
from airflow.providers.google.cloud.operators.pubsub import (
    PubSubCreateSubscriptionOperator,
    PubSubCreateTopicOperator,
    PubSubDeleteSubscriptionOperator,
    PubSubDeleteTopicOperator,
    PubSubPublishMessageOperator,
    PubSubPullOperator,
)
from airflow.providers.google.cloud.sensors.pubsub import PubSubPullSensor
from airflow.utils.trigger_rule import TriggerRule

[docs]ENV_ID = os.environ.get("SYSTEM_TESTS_ENV_ID")
[docs]PROJECT_ID = os.environ.get("SYSTEM_TESTS_GCP_PROJECT", "your-project-id")
[docs]DAG_ID = "pubsub"
[docs]TOPIC_ID = f"topic-{DAG_ID}-{ENV_ID}"
[docs]MESSAGE = {"data": b"Tool", "attributes": {"name": "wrench", "mass": "1.3kg", "count": "3"}}
[docs]MESSAGE_TWO = {"data": b"Tool", "attributes": {"name": "wrench", "mass": "1.2kg", "count": "2"}}
# [START howto_operator_gcp_pubsub_pull_messages_result_cmd]
[docs]echo_cmd = """ {% for m in task_instance.xcom_pull('pull_messages') %} echo "AckID: {{ m.get('ackId') }}, Base64-Encoded: {{ m.get('message') }}" {% endfor %} """
# [END howto_operator_gcp_pubsub_pull_messages_result_cmd] with models.DAG( DAG_ID, schedule='@once', # Override to match your needs start_date=datetime(2021, 1, 1), catchup=False, ) as dag: # [START howto_operator_gcp_pubsub_create_topic]
[docs] create_topic = PubSubCreateTopicOperator( task_id="create_topic", topic=TOPIC_ID, project_id=PROJECT_ID, fail_if_exists=False
) # [END howto_operator_gcp_pubsub_create_topic] # [START howto_operator_gcp_pubsub_create_subscription] subscribe_task = PubSubCreateSubscriptionOperator( task_id="subscribe_task", project_id=PROJECT_ID, topic=TOPIC_ID ) # [END howto_operator_gcp_pubsub_create_subscription] # [START howto_operator_gcp_pubsub_pull_message_with_sensor] subscription = subscribe_task.output pull_messages = PubSubPullSensor( task_id="pull_messages", ack_messages=True, project_id=PROJECT_ID, subscription=subscription, ) # [END howto_operator_gcp_pubsub_pull_message_with_sensor] # [START howto_operator_gcp_pubsub_pull_messages_result] pull_messages_result = BashOperator(task_id="pull_messages_result", bash_command=echo_cmd) # [END howto_operator_gcp_pubsub_pull_messages_result] # [START howto_operator_gcp_pubsub_pull_message_with_operator] pull_messages_operator = PubSubPullOperator( task_id="pull_messages_operator", ack_messages=True, project_id=PROJECT_ID, subscription=subscription, ) # [END howto_operator_gcp_pubsub_pull_message_with_operator] # [START howto_operator_gcp_pubsub_publish] publish_task = PubSubPublishMessageOperator( task_id="publish_task", project_id=PROJECT_ID, topic=TOPIC_ID, messages=[MESSAGE, MESSAGE], ) # [END howto_operator_gcp_pubsub_publish] publish_task2 = PubSubPublishMessageOperator( task_id="publish_task2", project_id=PROJECT_ID, topic=TOPIC_ID, messages=[MESSAGE_TWO, MESSAGE_TWO], ) # [START howto_operator_gcp_pubsub_unsubscribe] unsubscribe_task = PubSubDeleteSubscriptionOperator( task_id="unsubscribe_task", project_id=PROJECT_ID, subscription=subscription, ) # [END howto_operator_gcp_pubsub_unsubscribe] unsubscribe_task.trigger_rule = TriggerRule.ALL_DONE # [START howto_operator_gcp_pubsub_delete_topic] delete_topic = PubSubDeleteTopicOperator(task_id="delete_topic", topic=TOPIC_ID, project_id=PROJECT_ID) # [END howto_operator_gcp_pubsub_delete_topic] delete_topic.trigger_rule = TriggerRule.ALL_DONE ( create_topic >> subscribe_task >> publish_task >> pull_messages >> pull_messages_result >> publish_task2 >> pull_messages_operator >> unsubscribe_task >> delete_topic ) # Task dependencies created via `XComArgs`: # subscribe_task >> pull_messages # subscribe_task >> pull_messages_operator # subscribe_task >> unsubscribe_task # ### Everything below this line is not part of example ### # ### Just for system tests purpose ### from tests.system.utils.watcher import watcher # This test needs watcher in order to properly mark success/failure # when "tearDown" task with trigger rule is part of the DAG list(dag.tasks) >> watcher() from tests.system.utils import get_test_run # noqa: E402 # Needed to run the example DAG with pytest (see: tests/system/README.md#run_via_pytest)
[docs]test_run = get_test_run(dag)

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