update-state

Updates the dynamoDB state database with the State Function execution results.

Completion of a State Function execution can also be used to chain additional workflow steps with pushing messages to SQS or SNS for additional steps beyond the core cirrus workflow, like triggering a lambda to push an output STAC Item to a STAC API.

Trigger

The update-state lambda listens for terminal events output by a State Function that is executing a cirrus workflow/task. These terminal states are not an exclusive list of possible states in the StateDB.

  • “SUCCEEDED”: the successful completion of a cirrus workflow

  • “FAILED”: A failed execution. This can occur for a variety of reasons

  • “ABORTED”: The state machinea was forced to abort execution. Can be triggered by manual termination of a workflow.

  • “TIMED OUT”: State machine terminated due to time out. Can occur if a third party resource involved in a task hangs, or a workflow configuration did not allow sufficient time for a task to complete.

StateDB Updates

Updating the DynamoDB state database is the core functionality of the update-state lambda.

In addition to updating DynamoDB the update-state lambda also fires off events to AWS TimeStream with each state update.

The update-state lambda additionally logs any errors that come from the StateMachine so they can be captured and anlyzed in the log stream.

update-state can send messages to configured SNS topics to provide notifications to users or downstream services when events and/or output items are produced. It may also be used to facilitate workflow chaining by requeuing payloads in the process queue.