Public Rabbitmq Expert Base

RabbitMQ Knowledge Base

> Source: Adapted from mindrally/skills (rabbitmq-development) and RabbitMQ official documentation.

Exchange Types

| Type | Routing | Use for | |------|---------|---------| | Direct | Exact routing key match | Point-to-point, RPC | | Topic | Wildcard pattern (*.info, #) | Flexible pub/sub | | Fanout | Ignore routing key, broadcast to all bound queues | Broadcast notifications | | Headers | Match on message headers (not routing key) | Complex routing rules |

• Default exchange (empty name): direct routing by queue name. Convenient but not recommended for production.
• Always declare exchanges explicitly; don't rely on auto-created exchanges.

Queue & Routing

• Declare queues with durable=true for persistence across broker restarts.
• Bind queues to exchanges with routing keys.
• Use x-message-ttl for message expiration.
• Use x-max-length to cap queue size (drop or dead-letter oldest).
• Prefetch count (basic_qos): limit unacknowledged messages per consumer.

Durability & Reliability

• durable=true on queue + persistent delivery mode on message = survive broker restart.
• Publisher confirms: confirm_select() → broker acknowledges message receipt.
• Consumer acknowledgments: basic_ack (success) / basic_nack (failure, requeue or dead-letter).
• Never use auto_ack=true in production (message loss on consumer crash).

Dead Letter Exchange (DLX)

• Messages are dead-lettered when: rejected (basic_nack with requeue=false), TTL expired, or queue length exceeded.
• Configure with x-dead-letter-exchange and x-dead-letter-routing-key on the source queue.
• Use DLX for retry queues, error handling, and audit trails.
• Pattern: main queue → DLX → retry queue (with TTL) → main queue.

Connection & Channel

• One connection per application; multiple channels per connection.
• Channels are lightweight; connections are expensive (TCP + AMQP handshake).
• Use connection pooling for multi-threaded applications.
• Set heartbeat interval (default 60s) to detect dead connections.

Common Patterns

• Work queue: multiple consumers, round-robin dispatch, prefetch=1 for fair dispatch.
• Pub/Sub: fanout exchange, each subscriber has own queue.
• RPC: direct exchange, correlationid + replyto for request/response.
• Delay/Retry: DLX + TTL queue for delayed message processing.

Guardrails

• Always use publisher confirms and consumer acknowledgments.
• Never use auto_ack=true in production.
• Always declare queues and exchanges explicitly.
• Set prefetch count to prevent consumer overload.
• Monitor queue depth and consumer lag.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: seed-forge
• Source: seed-forge/harness-ai-kit
• License: Apache-2.0
• Homepage: https://pypi.org/project/harness-ai-kit/

Install and usage instructions live in the source repository linked above.