Simple Workflow Service

Simple Workflow Service - SWF

Overview

• Build workflows - cordination over distributed components
• Predecessor to Step Functions - uses Instances/Servers
• Same patterns/anti-patterns - long running workflows
• Activity Task and Activity Worker
• Decider
  • schedule task
  • provides inputs to activity worker
  • process events while workflow is in progress
  • ends the workflow when objective has been completed
• 1 years of maximum runtime

SWF vs step-functions

• Default - Step Functions - serverless/lower admin
• AWS Flow Framework --> SWF
• External Signals to intervene in process -> SWF
• Launch child flows - return to parent -> SWF
• Bespoke/complex decisions -> SWF (customer decider applications)
• Mechanical Turk -> SWF (suggested AWS architecture)
• Over time Step Functions will replace SWF