template.yml

AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31

Metadata:
  AWS::ServerlessRepo::Application:
    Name: lambda-versions-deleter
    Description: A serverless app that deletes old lambda function versions on a schedule.
    Author: Shweta Katdare
    # SPDX License Id, e.g., MIT, MIT-0, Apache-2.0. See https://spdx.org/licenses for more details
    SpdxLicenseId: Apache-2.0
    # paths are relative to .aws-sam/build directory
    LicenseUrl: ../../LICENSE
    ReadmeUrl: ../../README.md
    Labels: [aws, lambda, cloudwatch, serverless]
    HomePageUrl: https://github.com/shwetaskatdare/lambda-versions-deleter
    # Update the semantic version and run sam publish to publish a new version of your app
    SemanticVersion: 0.0.1
    # best practice is to use git tags for each release and link to the version tag as your source code URL
    SourceCodeUrl: https://github.com/shwetaskatdare/lambda-versions-deleter/tree/0.0.1

Parameters:
  LogLevel:
    Type: String
    Description: Log level for Lambda function logging, e.g., ERROR, INFO, DEBUG, etc
    Default: INFO
  FunctionArn:
    Type: String
    Description: Specify ARN of a Lambda function for which you want the versions to be deleted.
  LambdaExecutionSchedule:
    Type: String
    Description: Specify the schedule expression to invoke LambdaVersionsDeleter using https://docs.aws.amazon.com/lambda/latest/dg/tutorial-scheduled-events-schedule-expressions.html
    Default: cron(0 12 * * ? *)

Resources:
  LambdaVersionsDeleter:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: src/
      Handler: lambdaversionsdeleter.handler
      Runtime: python3.7
      Tracing: Active
      Timeout: 60
      Policies:
        - Version: '2012-10-17' # PolicyDocument
          Statement: 
            - Effect: Allow
              Action:
                - lambda:ListVersionsByFunction
                - lambda:DeleteFunction
              Resource: !Ref FunctionArn
      Environment:
        Variables:
          LOG_LEVEL: !Ref LogLevel
          FUNCTION_ARN: !Ref FunctionArn
      Events:
        LambdaVersionsDeleterSchedule:
          Type: Schedule
          Properties:
            Schedule: !Ref LambdaExecutionSchedule


Outputs:
  LambdaVersionsDeleter:
    Description: "Lambda Function Name"
    Value: !Ref LambdaVersionsDeleter
  LambdaVersionsDeleterArn:
    Description: "Lambda Function ARN"
    Value: !GetAtt LambdaVersionsDeleter.Arn