Stage 3 · Build
Testing & Release Confidence
Queue & Worker Tests
Test retries, idempotency keys, dead-letter paths, poison messages, and concurrent worker shutdown.
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Why Test Queues
Queue workers process jobs asynchronously. Bugs here cause silently lost jobs, duplicate processing, or stuck queues. Testing ensures retries work, idempotency prevents duplicates, and dead-letter queues capture failures.
Testing Retries
Gotesting-retry-behavior.go
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Test that workers retry on temporary failures. Test that they stop after max retries. Verify the error message indicates max retries exceeded.
Testing Idempotency
Gotesting-idempotent-processing.go
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Idempotency keys prevent duplicate processing. Send the same job twice with the same key. Verify the processor only runs once.
Testing Dead-Letter
Gotesting-dead-letter-queue.go
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After max retries, failed jobs should land in the dead-letter queue. Verify the job appears in the DLQ with the correct ID.
Testing Poison Messages
Gotesting-poison-message-handling.go
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Poison messages cause panics. Workers must recover from panics and send the message to DLQ. Verify the worker continues processing after a panic.
Testing Graceful Shutdown
Gotesting-worker-shutdown.go
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Graceful shutdown should complete all in-flight jobs. Submit jobs, then call Shutdown. Verify all jobs completed before shutdown returned.
Use channels for synchronization
In worker tests, use channels or sync.WaitGroup to wait for async operations. time.Sleep is unreliable. Use channels with timeouts for deterministic test assertions.
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