AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: >
  (uksb-1tthgi812) (tag:eventbridge-batch-sam)
Resources:
# Create a custom Event Bus
  EventBus:
    Type: AWS::Events::EventBus
    Properties:
      Name: "my-event-bus"
# Create Event Rule that filters events based on pattern and triggers AWS Batch for matching events       
  EventRule:
    Type: AWS::Events::Rule
    Properties:
      Name: "my-event-rule"
      EventBusName: !GetAtt EventBus.Arn
      Description: "Send matched events to AWS Batch"
      Targets: 
        - Arn: !Ref JobQueue
          Id: "my-batch-target"
          RoleArn: !GetAtt EventBridgeIAMrole.Arn
          BatchParameters:
            JobDefinition: !Ref JobDefinition
            JobName: 'my-job'
            RetryStrategy:
              Attempts: 2
      EventPattern:
        source:
          - "my-application"
# Create IAM Role that allows EventBridge to invoke AWS Batch         
  EventBridgeIAMrole:
    Type: 'AWS::IAM::Role'
    Properties:
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Principal:
              Service: !Sub events.amazonaws.com
            Action: 'sts:AssumeRole'
      Path: /
      Policies:
        - PolicyName: AWSBatchSubmitJob
          PolicyDocument:
            Version: 2012-10-17
            Statement:
              - Effect: Allow
                Action:
                  - 'batch:SubmitJob'
                Resource:
                  - !Ref JobQueue
                  - !Ref JobDefinition
                  - !Join
                    - ''
                    - - 'arn:'
                      - !Ref AWS::Partition
                      - ':batch:'
                      - !Ref AWS::Region
                      - ':'
                      - !Ref AWS::AccountId
                      - ':job/*'

# Create VPC, subnets, security groups, and single Batch Job Queue    
  VPC:
    Type: 'AWS::EC2::VPC'
    Properties:
      CidrBlock: 10.0.0.0/16
  InternetGateway:
    Type: 'AWS::EC2::InternetGateway'
  RouteTable:
    Type: 'AWS::EC2::RouteTable'
    Properties:
      VpcId: !Ref VPC
  VPCGatewayAttachment:
    Type: 'AWS::EC2::VPCGatewayAttachment'
    Properties:
      VpcId: !Ref VPC
      InternetGatewayId: !Ref InternetGateway
  SecurityGroup:
    Type: 'AWS::EC2::SecurityGroup'
    Properties:
      GroupDescription: EC2 Security Group for instances launched in the VPC by Batch
      VpcId: !Ref VPC
      SecurityGroupEgress:
        - Description: Allow all outbound traffic
          IpProtocol: "-1"
          CidrIp: 0.0.0.0/0      
  Subnet:
    Type: 'AWS::EC2::Subnet'
    Properties:
      CidrBlock: 10.0.0.0/24
      VpcId: !Ref VPC
      MapPublicIpOnLaunch: true
  Route:
    Type: 'AWS::EC2::Route'
    Properties:
      RouteTableId: !Ref RouteTable
      DestinationCidrBlock: 0.0.0.0/0
      GatewayId: !Ref InternetGateway
  SubnetRouteTableAssociation:
    Type: 'AWS::EC2::SubnetRouteTableAssociation'
    Properties:
      RouteTableId: !Ref RouteTable
      SubnetId: !Ref Subnet
  BatchServiceRole:
    Type: 'AWS::IAM::Role'
    Properties:
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Principal:
              Service: batch.amazonaws.com
            Action: 'sts:AssumeRole'
      ManagedPolicyArns:
        - 'arn:aws:iam::aws:policy/service-role/AWSBatchServiceRole'
  IamInstanceProfile:
    Type: 'AWS::IAM::InstanceProfile'
    Properties:
      Roles:
        - !Ref EcsInstanceRole
  EcsInstanceRole:
    Type: 'AWS::IAM::Role'
    Properties:
      AssumeRolePolicyDocument:
        Version: 2008-10-17
        Statement:
          - Sid: ''
            Effect: Allow
            Principal:
              Service: ec2.amazonaws.com
            Action: 'sts:AssumeRole'
      ManagedPolicyArns:
        - >-
          arn:aws:iam::aws:policy/service-role/AmazonEC2ContainerServiceforEC2Role
  JobDefinition:
    Type: 'AWS::Batch::JobDefinition'
    Properties:
      Type: container
      ContainerProperties:
        Image: !Join 
          - ''
          - - 137112412989.dkr.ecr.
            - !Ref 'AWS::Region'
            - '.amazonaws.com/amazonlinux:latest'
        Vcpus: 2
        Memory: 2000
        Command:
          - echo
          - Hello World!
      RetryStrategy:
        Attempts: 1
  JobQueue:
    Type: 'AWS::Batch::JobQueue'
    Properties:
      Priority: 1
      ComputeEnvironmentOrder:
        - Order: 1
          ComputeEnvironment: !Ref ComputeEnvironment
  ComputeEnvironment:
    Type: 'AWS::Batch::ComputeEnvironment'
    Properties:
      Type: MANAGED
      ComputeResources:
        Type: EC2
        MinvCpus: 0
        DesiredvCpus: 0
        MaxvCpus: 64
        InstanceTypes:
          - optimal
        Subnets:
          - !Ref Subnet
        SecurityGroupIds:
          - !Ref SecurityGroup
        InstanceRole: !Ref IamInstanceProfile
      ServiceRole: !Ref BatchServiceRole
Outputs:
  EventBusName:
    Value: !GetAtt EventBus.Arn
  JobQueueName:
    Value: !Select [1, !Split ['/', !Ref JobQueue]]
  JobDefinitionName:
    Value: !Select [0, !Split [":", !Select [1, !Split ['/', !Ref JobDefinition]]]]