RabbitMQ Core Knowledge

Full Reference: See advanced.md for producer patterns (Node.js, Java, Python, Go), consumer patterns, security configuration, and high availability setup.

Deep Knowledge: Use mcp__documentation__fetch_docs with technology: rabbitmq for comprehensive documentation.

Quick Start (Docker)

services:
  rabbitmq:
    image: rabbitmq:3-management
    ports:
      - "5672:5672"   # AMQP
      - "15672:15672" # Management UI
    environment:
      - RABBITMQ_DEFAULT_USER=admin
      - RABBITMQ_DEFAULT_PASS=admin

Core Concepts

Concept	Description
Exchange	Routes messages to queues
Queue	Buffer that stores messages
Binding	Rule linking exchange to queue
Routing Key	Message attribute for routing

Architecture

Producer ──▶ Exchange ──binding──▶ Queue ──▶ Consumer
                │
                ├── direct   (exact routing key match)
                ├── topic    (pattern matching)
                ├── fanout   (broadcast to all)
                └── headers  (header-based routing)

Exchange Types

Type	Routing	Use Case
direct	Exact key match	Task queues, RPC
topic	Pattern (*.#)	Event routing
fanout	Broadcast all	Notifications
headers	Header match	Complex routing

# Topic exchange patterns
order.*        → matches order.created, order.updated
order.#        → matches order.created, order.item.added
*.created      → matches order.created, user.created

Queue Configuration

Argument	Description
x-message-ttl	Message expiration (ms)
x-max-length	Max queue size
x-dead-letter-exchange	DLX for rejected messages
x-dead-letter-routing-key	DLQ routing key
x-queue-type	classic, quorum, stream

When NOT to Use This Skill

• Event streaming with replay - Kafka provides persistent log
• Ultra-high throughput (>100k msg/s) - Kafka or Pulsar scale better
• AWS-native architecture - SQS integrates better
• Lightweight messaging - NATS has simpler operations
• JMS compliance required - ActiveMQ provides JMS API

Anti-Patterns

Anti-Pattern	Why It's Bad	Solution
No prefetch limit	Consumer overwhelmed	Set prefetch to 10-50
Classic queues in HA	Data loss on node failure	Use quorum queues
No DLX configured	Poison messages loop forever	Configure dead letter exchange
Automatic acks	Message loss on crash	Use manual acks
No publisher confirms	Silent message loss	Enable confirms for critical messages

Quick Troubleshooting

Issue	Likely Cause	Fix
Messages piling up	Slow/dead consumer	Check consumer count and processing
High memory usage	Too many unacked messages	Reduce prefetch, add consumers
Messages not routed	Wrong routing key	Check exchange-queue bindings
Duplicate messages	Consumer crashed before ack	Implement idempotent processing
Publisher confirms timeout	Broker overloaded	Reduce publish rate

Production Checklist

• TLS/SSL enabled
• Users with least privilege
• Virtual hosts for isolation
• Quorum queues for HA
• Dead letter exchanges configured
• Message TTL set
• Prefetch limits configured
• Publisher confirms enabled
• Monitoring dashboards
• Alerting configured

Reference Documentation

Available topics: basics, exchanges, queues, consumers, clustering, production