Add InvalidateTopicExistsCache method to SeaweedMQHandlerInterface and impl
ement cache refresh logic in metadata response handler.
When a consumer requests metadata for a topic that doesn't appear in the
cache (but was just created by a producer), force a fresh broker check
and auto-create the topic if needed with default partitions.
This fix attempts to address the consumer stalling issue by:
1. Invalidating stale cache entries before checking broker
2. Automatically creating topics on metadata requests (like Kafka's auto.create.topics.enable=true)
3. Returning topics to consumers more reliably
However, testing shows consumers still can't find topics even after creation,
suggesting a deeper issue with topic persistence or broker client communication.
Added InvalidateTopicExistsCache to mock handler as no-op for testing.
Note: Integration testing reveals that consumers get 'topic does not exist'
errors even when producers successfully create topics. This suggests the
real issue is either:
- Topics created by producers aren't visible to broker client queries
- Broker client TopicExists() doesn't work correctly
- There's a race condition in topic creation/registration
Requires further investigation of broker client implementation and SMQ
topic persistence logic.
chrislu
a5db489f82