Talk at PHP Developers meet up #12 held on 23-Aug-2014. - the video of the talk and more description : http://bit.ly/1tLVbJV

1. Message Queues
A basic overview

2. Geshan Manandhar
Quality and Maintenance Lead, Namshi.com
@geshan
geshan.com.np

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

4. 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.

5. 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

6. Benefits of MQ
Decoupling
Scalability
Reliability
Fanout - Same message to multiple queues (Pub/Sub)

7. Rabbit MQ

8. 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

9. Our Software stack/services
relating to with Rabbit MQ
Symfony 2 with old sound rabbit mq bundle and Monolog
Rabbit Mq on http://www.cloudamqp.com/
Service Oriented Architecture (SOA) with 3rd party API
integrations

10. 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

11. 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.

12. Conclusion/Recap
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

14. Questions???

15. Credits
http://keyholesoftware.com/2013/05/13/messaging-with-rabbitmq/
https://www.flickr.com/photos/i8ipod/9028050858
https://www.flickr.com/photos/oberazzi/318947873/

16. Some programming mantras to remember.