Programming Amazon Web Services

Chapter 9. SQS Applications

Amazon’s Simple Queue Service (SQS) provides a messaging layer for tying together the components of distributed applications that run across multiple computers. This service is different from those we have already discussed, because it provides the “glue” to stick components together, rather than providing the building blocks for application components themselves. As such it makes little sense to talk about SQS in isolation; it must be considered in terms of a broader system that can be built on top of the messaging infrastructure.

In this chapter we will demonstrate how SQS can be used in combination with the Simple Storage Service (S3) and the Elastic Compute Cloud (EC2) service to build applications with heterogeneous components that are flexible, easy to deploy, scalable on demand, and cheap to run. In the Messaging Simulator” example we build a simple framework for simulating a distributed application that uses SQS messaging. This framework will help you to become familiar with the service, as well as providing a useful tool for testing how the service behaves in different situations. In Distributed Application Services with BOTO” we will work through the process of developing a real distributed application based on service components that run in EC2. This application will demonstrate how simple it can be to build truly scalable applications. Finally, in Automated Management of EC2 Instance Pools with Lifeguard,” we will add an intelligent ...