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

Resources:
  ## S3 bucket
  DestinationBucket:
    Type: AWS::S3::Bucket
    Properties:
      VersioningConfiguration:
        Status: Enabled    
      BucketName: 'my-sfn-bucket-destination'

  MyStateMachine:
    Type: AWS::Serverless::StateMachine
    Properties:
      Role: !GetAtt WorkflowExecutionRole.Arn
      Definition:
        StartAt: SendCustomEvent
        States:
          SendCustomEvent:
            Type: Task
            Resource: 'arn:aws:states:::aws-sdk:s3:putObject'
            Parameters:
                Body: 'Hello World'
                Bucket: !Ref DestinationBucket
                Key: 'filename.txt'
            End: True

  WorkflowExecutionRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Principal:
              Service: states.amazonaws.com
            Action: sts:AssumeRole
      Policies:
        - PolicyName: S3Write
          PolicyDocument:
            Version: "2012-10-17"
            Statement:
              - Effect: Allow
                Action:
                  - "s3:PutObject"
                Resource: !Sub "${DestinationBucket.Arn}/*"


Outputs:
  MyStateMachineArn:
    Value: !Ref MyStateMachine
  S3:
    Value: !GetAtt DestinationBucket.Arn
    Description: DestinationBucket Arn