Message Queues

A basic overview

Geshan Manandhar

Quality and Maintenance Lead,



  • What is Message Queue(MQ)
  • MQ basics - AMQP
  • Benefits
  • Rabbit MQ
  • Our setup/stack
  • When to use it /Practical Usecase
  • Logging and monitoring
  • Conclusion

What is Message Queue

  • "message queues and mailboxes are software-engineering components used for inter-process communication (IPC), or for inter-thread communication within the same process. They use a queue for messaging – the passing of control or of content." - Wikipedia
  • Message queue is a software components that allow producers to produce message to a queue managed by a message broker, these message are asynchronously consumed by consumers.

Message Queue Basics

  • Protocols : Advanced Message Queueing Protocol(AMQP) and Streaming Text Oriented Messaging Protocol(STOMP)
  • Types of Queue: Direct, Topic and Fanout
  • Producer/Publisher
  • Message Broker - Queue Exchange
  • Queue
  • Consumer

Benefits of MQ

  • Decoupling
  • Scalability
  • Reliability
  • Fanout - Same message to multiple queues (Pub/Sub)

Rabbit MQ

Rabbit MQ - features

  • Robust messaging for applications
  • Easy to use
  • Runs on all major operating systems
  • Supports a huge number of developer platforms
  • Open source and commercially supported

Our Software stack/services

relating to with Rabbit MQ

  • Symfony 2 with old sound rabbit mq bundle and Monolog
  • Rabbit Mq on
  • Service Oriented Architecture (SOA) with 3rd party API integrations

When to use message queues

Some practical use cases

  • Backend -> Frontend sync (db to NOSQL/Memcache)
  • Communication between multiple internal systems (without API)
  • Asynchronous 3rd party API calls
  • Notifications like email and sms
  • Handling large request asynchronously
  • Processing intensive tasks- like image resize

Logging and monitoring is vital

  • Only access and error logs from web server and database are surely not enough
  • Logs are first class citizen, adopt active logging from application level.(Monolog)
  • Use dedicated log management system like GrayLog 2
  • Monitor application activity in real-time with services like NewRelic
  • Log optimally and verbose enough to give enough information about the context.


  • Communication between two systems can be done even without APIs
  • Language agnostic implementation is enable by using message queues
  • Message queues could be that answer you were looking for, to communicate between different systems
  • For scalability, decoupling and reliability utilize message queues
  • You could potentially scale to 1 million message per second : Pivotal
  • Logging and monitoring are inevitable when doing asynchronous processing




Some programming mantras to remember.