AWSTemplateFormatVersion: "2010-09-09"
Transform: AWS::Serverless-2016-10-31
Description: EventBridge integration with Firehose
Parameters:
  PartnerEventSource:
    Description: Name of Partner Event Source
    Type: String
    Default: "aws.partner/freshworks.com/1342406/freshdesk"
  S3BucketName:
    Description: Name of s3 bucket where Freshdesk ticket events are stored
    Type: String
    Default: "frshdeskv1"

Resources:
  FreshdeskS3Bucket:
    Type: AWS::S3::Bucket
    Properties:
      BucketName: !Ref S3BucketName

  FirehoseDeliveryRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
          - Sid: ""
            Effect: Allow
            Principal:
              Service: firehose.amazonaws.com
            Action: "sts:AssumeRole"
            Condition:
              StringEquals:
                "sts:ExternalId": !Ref "AWS::AccountId"

  FirehoseDeliveryPolicy:
    Type: AWS::IAM::Policy
    Properties:
      PolicyName: firehose_delivery_policy
      PolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Action:
              - "s3:AbortMultipartUpload"
              - "s3:GetBucketLocation"
              - "s3:GetObject"
              - "s3:ListBucket"
              - "s3:ListBucketMultipartUploads"
              - "s3:PutObject"
            Resource:
              - !Sub "arn:aws:s3:::${FreshdeskS3Bucket}"
              - !Sub "arn:aws:s3:::${FreshdeskS3Bucket}/*"
      Roles:
        - !Ref FirehoseDeliveryRole

  InvokeProcessorLambdaPolicy:
    Type: AWS::IAM::Policy
    Properties:
      PolicyName: firehose_processor_lambda_policy
      PolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Action:
              - "lambda:InvokeFunction"
            Resource:
              - !GetAtt FirehoseProcessorLambda.Arn
      Roles:
        - !Ref FirehoseDeliveryRole

  FirehoseDeliveryStream:
    Type: AWS::KinesisFirehose::DeliveryStream
    Properties:
      ExtendedS3DestinationConfiguration:
        BucketARN: !Sub "arn:aws:s3:::${FreshdeskS3Bucket}"
        BufferingHints:
          IntervalInSeconds: 60
          SizeInMBs: 50
        CompressionFormat: UNCOMPRESSED
        RoleARN: !GetAtt FirehoseDeliveryRole.Arn
        ProcessingConfiguration:
          Enabled: true
          Processors:
            - Parameters:
                - ParameterName: LambdaArn
                  ParameterValue: !GetAtt FirehoseProcessorLambda.Arn
              Type: Lambda

  FirehoseProcessorLambda:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: lambdaprocessor/
      Handler: index.handler
      Runtime: nodejs12.x
      FunctionName: freshdesk-data-processor

  FreshDeskPartnerEventBus:
    Type: AWS::Events::EventBus
    Properties:
      EventSourceName: !Ref PartnerEventSource
      Name: !Ref PartnerEventSource

  PushToFirehoseRule:
    Type: "AWS::Events::Rule"
    Properties:
      Description: Test Freshdesk Events Rule
      EventBusName: !Ref PartnerEventSource
      EventPattern:
        account: [!Ref AWS::AccountId]
      Name: freshdeskeventrule
      State: ENABLED
      Targets:
        - Arn:
            Fn::GetAtt:
              - "FirehoseDeliveryStream"
              - "Arn"
          Id: "idfreshdeskeventrule"
          RoleArn: !GetAtt EventRuleTargetIamRole.Arn

  EventRuleTargetIamRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Version: "2012-10-17"
        Statement:
          - Sid: ""
            Effect: "Allow"
            Principal:
              Service:
                - "events.amazonaws.com"
            Action:
              - "sts:AssumeRole"
      Path: "/"
      Policies:
        - PolicyName: Invoke_Firehose
          PolicyDocument:
            Version: "2012-10-17"
            Statement:
              - Effect: "Allow"
                Action:
                  - "firehose:PutRecord"
                  - "firehose:PutRecordBatch"
                Resource:
                  - !GetAtt FirehoseDeliveryStream.Arn