## Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
## SPDX-License-Identifier: MIT-0

AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: Introduction to serverless for developers:part3 GitHub to Slack
  
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#  Parameters & Globals                                                  #
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Parameters:
  
  GitHubSecret:
    Type: String
    Description: your GitHub Secret.
    Default: ""

Resources:

  gitHubPAT:
    Type: AWS::SSM::Parameter
    Properties:
      Type: String
      Value: !Ref GitHubSecret
      Description: SSM Parameter for GitHub API.
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#   Lambda Functions                                                      #
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  GitHubPost:
    Type: AWS::Serverless::Function
    Description: A github handler when repo is pr'd
    Properties:
      Policies:
        - SSMParameterReadPolicy:
            ParameterName: !Ref gitHubPAT
        - DynamoDBCrudPolicy:
            TableName: DynamoTable
      CodeUri: functions/srcGitHub/
      Handler: app.handler
      Runtime: nodejs18.x
      Timeout: 8
      Environment:
        Variables:
          SSM: !Ref gitHubPAT
          Table: !Ref DynamoTable

    #  Order Manager SFN                                                   #
  GitHubTrafficTracker:
    Type: AWS::Serverless::StateMachine # More info about State Machine Resource: https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-resource-statemachine.html
    Properties:
      DefinitionUri: statemachine/statemachine.asl.json
      DefinitionSubstitutions:
        FunctionNameGitHub: !Ref GitHubPost
        table: !Ref DynamoTable
      Policies:
      - LambdaInvokePolicy:
          FunctionName: !Ref GitHubPost
      - DynamoDBWritePolicy:
          TableName: !Ref DynamoTable
      - DynamoDBReadPolicy:
          TableName: !Ref DynamoTable

  # Schedule that will run every day at 00:00 to trigger process
  GitHubTrafficTrackerSchedule:
    Type: AWS::Scheduler::Schedule
    Properties:
      Description: Schedule the runs every day to start teh workflow
      FlexibleTimeWindow:
        Mode: 'OFF'
      ScheduleExpression: 'cron(24 14 * * ? *)'
      Target:
        Arn: !GetAtt GitHubTrafficTracker.Arn
        RoleArn: !GetAtt GitHubTrafficTrackerScheduleRole.Arn

  GitHubTrafficTrackerScheduleRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Principal:
              Service:
                - scheduler.amazonaws.com
            Action:
              - sts:AssumeRole
      Policies:
        - PolicyName: invokeGitHubTrafficTrackerSFN
          PolicyDocument:
            Version: 2012-10-17
            Statement:
              - Effect: Allow
                Action:
                  - 'states:startExecution'
                Resource:
                  - !GetAtt GitHubTrafficTracker.Arn


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#   DynamoDB                                                            #
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  DynamoTable:
    Type: AWS::DynamoDB::Table
    Properties:
      AttributeDefinitions:
        - AttributeName: PK
          AttributeType: S
        - AttributeName: SK
          AttributeType: S
      KeySchema:
        - AttributeName: PK
          KeyType: HASH
        - AttributeName: SK
          KeyType: RANGE
      BillingMode: PAY_PER_REQUEST
      StreamSpecification:
        StreamViewType: NEW_AND_OLD_IMAGES

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#   Stack outputs                                                        #
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