AWS SWF

SWF Simple Workflow Service
Web service to coordinate work across distributed application components

• task oriented API
• Simple Work flow – human interaction to complete order or collection of services to complete a work order.
• Workers – interact with SWF to get task, process received task and return the result
• Deciders – program that co-ordinates the tasks, i.e. – ordering, concurrency and scheduling
• Workers and Deciders can run independently
• TASK is only assigned ONCE and NEVER DUPLICATED (key difference from SQS where messages can be processed multiple times)
• SWF Domain – think of it as a container for the work flow. you can register a domain by Console or API
• Maximum workflow processing time can last 1 year (equivalent seconds) – SQS is 12 hours processing time

SWF vs SQS main difference is the guarantee of delivery order messages and tasks

SWF use case video encoding with swf app is built as a workflow where each video file is handled as one workflow execution

SWF – make sure you know that the containers are called DOMAINS

You can use IAM to manage access!

Humans cannot perform decision tasks only acting tasks.

Decider, Activity Worker, workflow starter

Assigned once never duplicated, last up to a year

Max number of workflows = 10,000

Use case – media processing, business process automation, data analytics, migration to the cloud, and batch processing

Flow framework helps in developing SWF

Max number of open tasks is 1,000

Can be managed across availability zones