template.yml

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

Metadata:
  AWS::ServerlessRepo::Application:
    Name: lambda-janitor
    Description: Cron job for deleting old, unused versions of Lambda functions to clean up storage space
    Author: Lumigo
    SpdxLicenseId: MIT
    LicenseUrl: LICENSE.txt
    ReadmeUrl: README.md
    Labels: ['lambda', 'cron']
    HomePageUrl: https://github.com/lumigo/SAR-Lambda-Janitor
    SemanticVersion: 1.5.0
    SourceCodeUrl: https://github.com/lumigo/SAR-Lambda-Janitor

Resources:
  Clean:
    Type: AWS::Serverless::Function
    Properties:
      Handler: functions/clean.handler
      Runtime: nodejs10.x
      Timeout: 900
      Environment:
        Variables:
          LOG_LEVEL: INFO
          VERSIONS_TO_KEEP:
            Ref: VersionsToKeep
          AWS_NODEJS_CONNECTION_REUSE_ENABLED: 1
      Policies:
        - Statement:
            Effect: Allow
            Action:
              - lambda:DeleteFunction
              - lambda:List*
            Resource: "*"
      Events:
        CleanScheduledEvent:
          Type: Schedule
          Properties:
            Schedule: rate(1 hour)

  LogGroup:
    Type: AWS::Logs::LogGroup
    Properties:
      LogGroupName: !Sub /aws/lambda/${Clean}

Parameters:
  VersionsToKeep:
    Type: Number
    Description: >-
      How many versions to keep, even if they are not aliased.
    Default: 3
    MinValue: 0 # don't keep anything except $Latest