By design, for every subscription the Google Cloud PubSub delivers messages at least once. Hence, even if the subscriber is not present <https://cloud.google.com/pubsub/docs/faq#persistent>, the unacknowledged messages are stored in a persistent storage for 7 days after the messages are published.
The documentation <https://cloud.google.com/pubsub/docs/subscriber#at-least-once-delivery> explains the exceptions to the "at least once delivery" approach of the Cloud PubSub and why a message would be deleted. Messages published before a subscription is created would not be retrievable. Also, a maximum retention of 7 days, after which the message would be deleted. Hence, it is intended behavior that your Subscriber would still be able to retrieve backlogs of messages (that are under 7 days), even if it was off for some time. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/google-appengine. To view this discussion on the web visit https://groups.google.com/d/msgid/google-appengine/e75be439-ee56-4644-8858-42a3cac88dbb%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
