warmup-function.yaml

AWSTemplateFormatVersion: "2010-09-09"
Description:
  Function to perform service discovery tags based and puts a scaling rule

Transform:
  - AWS::Serverless-2016-10-31

Metadata:
  Maintainer: john@compose-x.io
  AWS::CloudFormation::Interface:
    ParameterGroups:
      - Parameters:
          - LambdaLayerVersionArn
        Label:
          default: Lambda Settings
      - Parameters:
          - PermissionsBoundary
        Label:
          default: IAM Settings


Parameters:
  PermissionsBoundary:
    Type: String
    Default: none
    Description: IAM Policy ARN to use for PermissionsBoundary if required. Optional.

  LambdaLayerVersionArn:
    Type: String
    Description: Lambda Layer ARN to use with the function(s)

  FunctionsPrefix:
    Type: String
    Default: ecsScalingScheduler

  ServicesWarmupTags:
    Type: String
    Description: The list of tags and values to use to perform service discovery.

  ServiceDimensionTag:
    Type: String
    Default: warmup-dimension
    Description: Tag associated with the service to identify the dimension

  ServiceWarmupDurationTag:
    Type: String
    Description: Tag on the service that indicates duration of warmup.

  ServicesCluster:
    Type: String
    Description: ECS Cluster to scan services into.

  TriggerTopicName:
    Type: String

  LogLevel:
    Type: String
    Default: INFO
    AllowedValues:
      - INFO
      - ERROR
      - WARNING
      - DEBUG
      - CRITICAL

Conditions:
  PermissionsBoundaryCon: !Not [!Equals [!Ref PermissionsBoundary, "none"]]
  OverrideFunctionName: !Not [!Equals [!Ref FunctionsPrefix, "none"]]

Resources:
  ###############################################
  # ECS Warmup via Services Tags discovery

  SnsTriggerTopic:
    Type: AWS::SNS::Topic
    Properties:
      TopicName: !Ref TriggerTopicName

  ecsScalingSchedulerPolicy:
    DependsOn: ecsWarmupSchedulerFunctionRole
    Type: AWS::IAM::Policy
    Properties:
      Roles:
        - !Ref ecsWarmupSchedulerFunctionRole
      PolicyName: "ECSScheduler"
      PolicyDocument:
        Version: 2012-10-17
        Statement:
          - Sid: DescribeAllEcs
            Effect: Allow
            Action:
              - ecs:Describe*
              - ecs:List*
              - ecs:Get*
            Resource:
              - "*"
          - Sid: ScalingPolicyActions
            Effect: Allow
            Action:
              - "application-autoscaling:Describe*"
              - "application-autoscaling:PutScheduledAction"
              - "application-autoscaling:DeleteScheduledAction"
            Resource:
              - "*"

  ecsWarmupSchedulerFunctionRole:
    Type: AWS::IAM::Role
    Properties:
      ManagedPolicyArns:
        - arn:aws:iam::aws:policy/service-role/AWSLambdaVPCAccessExecutionRole
        - arn:aws:iam::aws:policy/ResourceGroupsandTagEditorReadOnlyAccess
      AssumeRolePolicyDocument:
        Statement:
          - Action:
              - sts:AssumeRole
            Condition:
              Bool:
                aws:SecureTransport: 'true'
            Effect: Allow
            Principal:
              Service:
                - !Sub 'lambda.${AWS::URLSuffix}'
        Version: '2012-10-17'
      Description: !Sub 'ecsWarmupSchedulerFunctionRole-${AWS::StackName}'
      PermissionsBoundary: !If
        - PermissionsBoundaryCon
        - !Ref PermissionsBoundary
        - !Ref AWS::NoValue


  ecsWarmupAtScalingScheduler:
    Type: AWS::Serverless::Function
    DependsOn:
      - SnsTriggerTopic
    Properties:
      Tags:
        Name: ecs-scaling-scheduler-Warmup-at-action
        Source: https://github.com/compose-x/ecs-scaling-scheduler
      FunctionName: !If
        - OverrideFunctionName
        - !Sub '${FunctionsPrefix}-WarmupScheduler'
        - !Sub '${AWS::StackName}-WarmupScheduler'
      Runtime: python3.8
      Handler: index.lambda_handler
      Timeout: 60
      Role: !GetAtt ecsWarmupSchedulerFunctionRole.Arn
      Layers:
        - !Ref LambdaLayerVersionArn
      Environment:
        Variables:
          WARMUP_ECS_SERVICES_TAGS: !Ref ServicesWarmupTags
          WARMUP_DURATION_TAG: !Ref ServiceWarmupDurationTag
          ECS_CLUSTER_NAME: !Ref ServicesCluster
          LOG_LEVEL: !Ref LogLevel

      InlineCode: |
        #!/usr/bin/env python
        from ecs_scaling_scheduler.aws_lambda_functions import services_event_warmup as handler


        def lambda_handler(event, context):
            """ Entry point function """
            return handler(event, context)
      Events:
        SnsTrigger:
          Type: SNS
          Properties:
            Topic:
              !Ref SnsTriggerTopic

Outputs:
  WarmupSchedulerFunctionArn:
    Value: !GetAtt ecsWarmupAtScalingScheduler.Arn

  WarmupSchedulerFunctionName:
    Value: !Ref "ecsWarmupAtScalingScheduler"