NOTE: If you don't need to create topic and subscription programatically, you can Create Topic or Subscription via Cloud Console or gcloud.
Install python libraries.
pip install --upgrade google-cloud-pubsubCreate Topic
from google.cloud import pubsub_v1GOOGLE_PROJECT_ID = ...TOPIC = ...publisher = pubsub_v1.PublisherClient()# topic_path = f"projects/{GOOGLE_PROJECT_ID}/topics/{TOPIC}"topic_path = publisher.topic_path(GOOGLE_PROJECT_ID, TOPIC)publisher.create_topic(topic_path)Create Subscription
import googlefrom google.cloud import pubsub_v1GOOGLE_PROJECT_ID = ...TOPIC = ...SUB = ...subscriber = pubsub_v1.SubscriberClient()# subscription_path = f"projects/{GOOGLE_PROJECT_ID}/subscriptions/{SUB}"subscription_path = subscriber.subscription_path(GOOGLE_PROJECT_ID, SUB)# topic_path = f"projects/{GOOGLE_PROJECT_ID}/topics/{TOPIC}"topic_path = subscriber.topic_path(GOOGLE_PROJECT_ID, TOPIC)try: subscriber.create_subscription(name=subscription_path, topic=topic_path)except google.api_core.exceptions.AlreadyExists: print(f"{subscription_path} already exist")NOTE: Publish and subscribe messages via Python.
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