A workflow service that you can use to build scalable applications has been released by Amazon.
The service provides the means to automate business processes where the tasks that make up an overall transaction may be distributed across multiple systems, but where the whole process needs to happen in a coordinated set of steps.
The service, Amazon SWF, was accidentally revealed last week when the acronym appeared as a service on Amazon’s listing of services for the free web tier. The service was then removed from the list, but has now been re-instated and details of just what’s on offer are now available.
The service lets you identify processing steps in your applications as tasks, and SWF then co-ordinates the tasks to be carried out correctly and in a scalable manner. Amazon SWF manages any task dependencies, scheduling, and concurrency based on the logic within your application. The service stores tasks, reliably dispatches them to application components, tracks their progress, and keeps their latest state.
The application can consist of distributed components, and Amazon SWF will track the execution state across the components so you don’t have to include code to deal with maintaining the distributed execution state. SWF will dispatch the tasks, though your code can control the routing. The service comes with a programming framework, the AWS Flow Framework, that you use to incorporate asynchronous and event-driven programming into your applications.
You can try out Amazon SWF with Amazon’s free usage tier. Once you are a registered user, you can also run a sample workflow in the AWS Management Console.