AWSTemplateFormatVersion: "2010-09-09"
Transform: AWS::Serverless-2016-10-31
Description: Serverless patterns - S3 to EventBridge to Step Functions

Resources:
  # Creates an Amazon S3 bucket to which images will be uploaded to trigger our workflow.
  IngestionBucket:
    Type: "AWS::S3::Bucket"
    Properties:
      # Amazon EventBridge receives notifications for all events in the bucket.
      NotificationConfiguration:
        EventBridgeConfiguration:
          EventBridgeEnabled: true

  # Creates a Step Functions workflow.
  CatDetectorStateMachine:
    Type: AWS::Serverless::StateMachine
    Properties:
      # The statemachine.asl.json file contains a sample workflow definition.
      DefinitionUri: statemachine/statemachine.asl.json
      Policies:
        - RekognitionDetectOnlyPolicy: {}
        - S3ReadPolicy:
            BucketName: !Ref IngestionBucket
      # The Step Functions workflow is triggered each time an object is created in our S3 bucket.
      Events:
        StateChange:
          Type: EventBridgeRule
          Properties:
            EventBusName: default
            Pattern:
              source:
                - aws.s3
              detail-type:
                - Object Created
              detail:
                bucket:
                  name:
                    - !Ref IngestionBucket

Outputs:
  IngestionBucket:
    Description: "S3 bucket name"
    Value: !Ref IngestionBucket
  CatDetectorStateMachine:
    Description: "Example state machine"
    Value: !Ref CatDetectorStateMachine