template.yaml

AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: >
  SAM Template that allow you to schedule a CRON job to perform START, STOP or REBOOT for
  EC2 INSTANCES that match TAG_KEY and TAG_VALUE

  Refer: https://github.com/devops-made-easy/ec2-cron


Globals:
  Function:
    Timeout: 300

Parameters:
  TagKey:
    Type: String
    Description: Name of the Tag Key associated to EC2 instance. Example=Name
  TagValue:
    Type: String
    Description: Value of the Tag Key associated to EC2 instance. Example=Demo
  Action:
    Type: String
    AllowedValues: [ "START" , "STOP", "REBOOT" ]
    Description: Action to be performed on associated EC2 instance. Allowed Values are  "START" or "STOP" or "REBOOT".
  CronSchedule:
    Type: String
    Description: Refer https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/ScheduledEvents.html

Metadata:
  AWS::ServerlessRepo::Application:
    Name: ec2-cron
    Description: SAM Template that allow you to schedule a CRON job(cloudwatch rule) to perform START, STOP or REBOOT for EC2 INSTANCES for given tag key and its value.
    Author: devops-made-easy
    SpdxLicenseId: MIT
    LicenseUrl: LICENSE
    ReadmeUrl: README.md
    Labels: ['devops-made-easy', "ec2-start-stop", "savings", "auto-start-stop-reboot", "ec2", "cron", "scheduler", "cronjob", "cloudwatch", "automation"]
    HomePageUrl: https://github.com/devops-made-easy/ec2-cron
    SemanticVersion: 1.0.5
    SourceCodeUrl: https://github.com/devops-made-easy/ec2-cron

Resources:
  EC2CronFunction:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: ec2_cron/
      Handler: app.lambda_handler
      Runtime: python3.8
      Environment:
        Variables:
          TAG_KEY: !Ref TagKey
          TAG_VALUE: !Ref TagValue
          ACTION: !Ref Action
      Policies:
        - Statement:
            - Effect: "Allow"
              Action:
                - "ec2:RebootInstances"
                - "ec2:StartInstances"
                - "ec2:StopInstances"
              Resource: !Sub "arn:aws:ec2:${AWS::Region}:${AWS::AccountId}:instance:*"
            - Effect: "Allow"
              Action:
                - "ec2:DescribeInstances"
              Resource: '*'
      Events:
        CloudWatchEvent:
          Type: Schedule
          Properties:
            Schedule:
              Ref: CronSchedule



#Outputs:
#  # ServerlessRestApi is an implicit API created out of Events key under Serverless::Function
#  # Find out more about other implicit resources you can reference within SAM
#  # https://github.com/awslabs/serverless-application-model/blob/master/docs/internals/generated_resources.rst#api
#  HelloWorldApi:
#    Description: "API Gateway endpoint URL for Prod stage for Hello World function"
#    Value: !Sub "https://${ServerlessRestApi}.execute-api.${AWS::Region}.amazonaws.com/Prod/hello/"
#  HelloWorldFunction:
#    Description: "Hello World Lambda Function ARN"
#    Value: !GetAtt HelloWorldFunction.Arn
#  HelloWorldFunctionIamRole:
#    Description: "Implicit IAM Role created for Hello World function"
#    Value: !GetAtt HelloWorldFunctionRole.Arn