AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: Image Processing service - Find text in images

Parameters:
  BucketNameForImages:
    Type: String

Resources:

  # Event Rule for new event in AWS EventBridge
  S3NewImageEvent:
    Type: 'AWS::Events::Rule'
    Properties:
      Description: This rule will trigger lambda when an image is uploaded into S3
      EventPattern:
        source:
          - aws.s3
          - simulated.aws.s3
        detail-type:
          - AWS API Call via CloudTrail
        detail:
          eventSource:
            - s3.amazonaws.com
          eventName:
            - PutObject
            - CopyObject
            - CompleteMultipartUpload
          requestParameters:
            bucketName: [!Sub "${BucketNameForImages}"]
      State: ENABLED
      Targets:
        - Arn: !GetAtt TextRecognitionLambda.Arn
          Id: !Sub 'TextRecognitionLambdaFunction'

  # Role for Lambda
  TextRecognitionLambdaRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Statement:
          - Action: sts:AssumeRole
            Effect: Allow
            Principal:
              Service:
                - lambda.amazonaws.com
        Version: '2012-10-17'
      Path: /
      Policies:
        - PolicyDocument:
            Statement:
              - Action:
                  - logs:CreateLogGroup
                  - logs:DescribeLogGroups
                  - logs:CreateLogStream
                  - logs:DescribeLogStreams
                  - logs:PutLogEvents
                Effect: Allow
                Resource:
                  - !Sub 'arn:aws:logs:${AWS::Region}:${AWS::AccountId}:log-group:*'
              - Action:
                  - 's3:GetObject'
                Effect: Allow
                Resource: 'arn:aws:s3:::*'
              - Action:
                  - rekognition:DetectText
                Effect: Allow
                Resource: "*"
            Version: '2012-10-17'
          PolicyName: TextRecognitionLambdaPolicy
      RoleName: TextRecognitionLambdaRole

  # Lambda
  TextRecognitionLambda:
    Type: AWS::Serverless::Function
    DependsOn: TextRecognitionLambdaRole
    Properties:
      CodeUri: src/
      Handler: app.handler
      Runtime: nodejs12.x
      Description: Lambda function that will recieve CloudWatch events and will trigger
        CodeBuild build job.
      FunctionName: 'TextRecognitionLambdaFunction'
      Role: !GetAtt TextRecognitionLambdaRole.Arn
      Timeout: 250

  PermissionForEventsToInvokeLambda:
    Type: AWS::Lambda::Permission
    Properties:
      Action: lambda:InvokeFunction
      FunctionName: !Ref TextRecognitionLambda
      Principal: events.amazonaws.com
      SourceArn: !GetAtt S3NewImageEvent.Arn