Option to disable topic existence verification in the Spring Cloud GCP Pub/Sub Binder

[burkedavison]

When Spring Cloud Stream calls provisionConsumerDestination and provisionProducerDestination on the Spring Cloud GCP PubSubChannelProvisioner, the method ensureTopicExists is called and invokes pubsubAdmin.getTopic. This can cause GCP quota issues if it occurs too often.

Workaround: Increase spring.cloud.stream.dynamic-destination-cache-size. (Add'l documentation)

Feature Request: As an alternative, Spring Cloud GCP could provide some mechanism to optionally disable topic existence verification in the Spring Cloud GCP Pub/Sub Binder implementation.

[smahieu87]

We had the same issue but for us the SA didn't have view access on the topic. To resolve our issue we just set the auto-create-resources to false and it doesn't do the ensureTopicExists anymore for the consumer part.
Would be nice if the same was possibility for option for the producer part.