Add Redis Pub/Sub bug tracking and test endpoint#85
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sohankshirsagar wants to merge 1 commit intomainfrom
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Add Redis Pub/Sub bug tracking and test endpoint#85sohankshirsagar wants to merge 1 commit intomainfrom
sohankshirsagar wants to merge 1 commit intomainfrom
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Found 1 confirmed bug: PubSub.execute_command() is not patched by the Redis instrumentation. The PubSub class has its own execute_command() method separate from Redis.execute_command(), so pub/sub operations (subscribe, get_message, listen) bypass instrumentation entirely. During replay, PubSub operations attempt real network connections which fail. Tested 19 potential bug scenarios across all Redis data types and patterns including: pipelines, scan iterators, blocking ops, Lua scripts, async operations, streams, geo, sets, sorted sets, locks, from_url clients, hash mappings, large payloads, and more. Only the pub/sub pattern failed replay. https://claude.ai/code/session_015MZ4GuLMi8eqzUVffB2hxa
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| def subscriber_thread(): | ||
| """Subscribe in a separate thread to receive messages.""" | ||
| sub_client = redis.Redis( | ||
| host=os.getenv("REDIS_HOST", "localhost"), |
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Subscriber uses wrong default Redis host
Medium Severity
The sub_client in subscriber_thread defaults to "localhost" for REDIS_HOST, while every other Redis client in this file (lines 20, 150, 185) defaults to "redis". In any environment where REDIS_HOST is not explicitly set (e.g., outside Docker), the subscriber connects to a different host than the publisher, causing message delivery to silently fail.
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Summary
This PR adds comprehensive bug tracking documentation for Redis instrumentation testing and introduces a new test endpoint that exposes a bug in Pub/Sub message handling during replay mode.
Key Changes
Added BUG_TRACKING.md: Comprehensive test results document covering 19 test scenarios for Redis instrumentation, including:
Added
/test/pubsub-publishendpoint: New test endpoint that demonstrates the Pub/Sub instrumentation bug:Redis.execute_command()(which is patched)PubSub.execute_command()(which is NOT patched)Updated test_requests.py: Added call to the new Pub/Sub test endpoint in the test suite
Notable Implementation Details
The identified bug occurs because:
Redis.execute_command(),Pipeline.execute(), and their async variantsPubSubclass has its own separateexecute_command()method that manages a persistent connection for receiving messagesThe bug affects any code that creates a PubSub subscriber within a request handler context during replay mode.