AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: |
  A Step Functions Standard Workflow doing PUT and GET operations directly on DynamoDB
Parameters:
  DdbTableName:
    Type: String
    Default: my-table
Resources:
  MyDdbTable:
    Type: AWS::DynamoDB::Table
    Properties:
      AttributeDefinitions:
        - AttributeName: id
          AttributeType: S
      BillingMode: PAY_PER_REQUEST
      KeySchema:
        - AttributeName: id
          KeyType: HASH
      TableName: !Ref DdbTableName
  StateMachinetoDDB:
    Type: AWS::Serverless::StateMachine
    Properties:
      Definition:
        StartAt: SendToDDB
        States:
          SendToDDB:
            Type: Task
            Resource: arn:aws:states:::dynamodb:putItem
            ResultPath: $.output_from_ddb_put
            Parameters:
              TableName: !Ref DdbTableName
              Item:
                id.$: $.id
                description.$: States.Format('Hello, my id is {}.', $.id)
            Next: ReadFromDDB
          ReadFromDDB:
            Type: Task
            Resource: arn:aws:states:::dynamodb:getItem
            Parameters:
              TableName: !Ref DdbTableName
              Key:
                id.$: $.id
            ResultPath: $.output_from_ddb_get
            OutputPath: $.output_from_ddb_get.Item
            End: true
      Role: !GetAtt MyStateMachineExecutionRole.Arn
  MyStateMachineExecutionRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Version: '2012-10-17'
        Statement:
          - Effect: Allow
            Principal:
              Service:
                - !Sub states.${AWS::Region}.amazonaws.com
            Action: sts:AssumeRole
      Path: /
      Policies:
        - PolicyName: DDBPolicy
          PolicyDocument:
            Version: '2012-10-17'
            Statement:
              - Effect: Allow
                Action:
                  - dynamodb:PutItem
                  - dynamodb:GetItem
                Resource: !GetAtt MyDdbTable.Arn
Outputs:
  StateMachinetoDDBArn:
    Value: !Ref StateMachinetoDDB
    Description: StateMachinetoDDB Arn
  TableName:
    Value: !Ref DdbTableName
    Description: DynamoDb Table Name