---
AWSTemplateFormatVersion: 2010-09-09
Transform: AWS::Serverless-2016-10-31
Description: >-
  This AWS SAM (Serverless Application Model) template creates CFN resources to Schedule Auto Start-Stop of EC2 instances to save cost.
  This involves creating 6 Lambda functions with IAM Policies and Schedule Events in EventBridge Rules.
  User also gets 5 Parameter options, in which 4 to be set in EventBridge Rules and 1 to set in Lambda Functions Environment variable.
  Written by - Pinesh Singal (spinesh@), last modified 27-Feb-2022

Parameters:
  AutoStartEC2Schedule:
    Default: cron(0 13 ? * MON-FRI *)
    Description: Auto Start EC2 Instance (Mon-Fri 9:00 AM EST / 1:00 PM GMT), enter a Schedule expression e.g. cron(0 13 ? * MON-FRI *), see https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/ScheduledEvents.html
    Type: String
    MinLength: 20
    MaxLength: 30
  AutoStopEC2Schedule:
    Default: cron(0 1 ? * MON-FRI *)
    Description: Auto Stop EC2 Instance (Mon-Fri 9:00 PM EST / 1:00 AM GMT), enter a Schedule expression e.g. cron(0 1 ? * MON-FRI *), see https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/ScheduledEvents.html
    Type: String
    MinLength: 20
    MaxLength: 30
  EC2StartStopWeekDaySchedule:
    Default: cron(*/5 * ? * MON-FRI *)
    Description: EC2 Start Stop triggering every Week Day every 5 mins
    Type: String
    MinLength: 20
    MaxLength: 30
  EC2StartStopWeekEndSchedule:
    Default: cron(*/5 * ? * SAT-SUN *)
    Description: EC2 Start Stop triggering every Week End every 5 mins
    Type: String
    MinLength: 20
    MaxLength: 30
  RegionTZ:
    Default: UTC
    Type: String
    AllowedValues:
      - UTC
      - US/Eastern
      - US/Pacific
      - Africa/Johannesburg
      - Asia/Hong_Kong
      - Asia/Kolkata
      - Asia/Tokyo
      - Asia/Seoul
      - Asia/Singapore
      - Australia/Sydney
      - Canada/Central
      - Europe/Berlin
      - Europe/Dublin
      - Europe/London
      - Europe/Rome
      - Europe/Paris
      - Europe/Stockholm
      - Asia/Bahrain
      - America/Sao_Paulo
    Description: Select Timezone of your Region for execution time in Tags (Set as Lambda Environment Variable Key REGION_TZ)

Resources:

  AutoStartEC2Lambda:
    Type: AWS::Serverless::Function
    Properties:
      FunctionName: AutoStartEC2Instance
      Runtime: python3.9
      MemorySize: 128
      Handler: AutoStartEC2Instance.lambda_handler
      Timeout: 60
      ReservedConcurrentExecutions: 10
      Policies:
        - AWSLambdaBasicExecutionRole
        - Version: 2012-10-17
          Statement:
            - Effect: Allow
              Action:
                - ec2:StartInstances
                - ec2:StopInstances
              Resource: arn:aws:ec2:*:*:instance/*
            - Effect: Allow
              Action:
                - ec2:DescribeInstances
                - ec2:DescribeTags
                - ec2:DescribeInstanceStatus
              Resource: '*'
      CodeUri: ./lambda/AutoStartEC2Instance.py
      Events:
        AutoStartEC2Rule:
          Type: Schedule
          Properties:
            Name: AutoStartEC2Rule
            Description: "Auto Start EC2 Instance (Mon-Fri 9:00 AM EST / 1:00 PM GMT)"
            Schedule: !Ref AutoStartEC2Schedule
            Enabled: true
      Description: >-
        Auto Start EC2 Instance (from tag : AutoStart)

  AutoStopEC2Lambda:
    Type: AWS::Serverless::Function
    Properties:
      FunctionName: AutoStopEC2Instance
      Runtime: python3.9
      MemorySize: 128
      Handler: AutoStopEC2Instance.lambda_handler
      Timeout: 60
      ReservedConcurrentExecutions: 10
      Policies:
        - AWSLambdaBasicExecutionRole
        - Version: 2012-10-17
          Statement:
            - Effect: Allow
              Action:
                - ec2:StartInstances
                - ec2:StopInstances
              Resource: arn:aws:ec2:*:*:instance/*
            - Effect: Allow
              Action:
                - ec2:DescribeInstances
                - ec2:DescribeTags
                - ec2:DescribeInstanceStatus
              Resource: '*'
      CodeUri: ./lambda/AutoStopEC2Instance.py
      Events:
        AutoStopEC2Rule:
          Type: Schedule
          Properties:
            Name: AutoStopEC2Rule
            Description: "Auto Stop EC2 Instance (Mon-Fri 9:00 PM EST / 1:00 AM GMT)"
            Schedule: !Ref AutoStopEC2Schedule
            Enabled: true
      Description: >-
        Auto Stop EC2 Instance (from tag : AutoStop)

  EC2StopWeekDayLambda:
    Type: AWS::Serverless::Function
    Properties:
      FunctionName: EC2StopWeekDay
      Runtime: python3.9
      MemorySize: 128
      Handler: EC2StopWeekDay.lambda_handler
      Timeout: 60
      ReservedConcurrentExecutions: 10
      Environment:
          Variables:
            REGION_TZ:
              Ref: RegionTZ
      Policies:
        - AWSLambdaBasicExecutionRole
        - Version: 2012-10-17
          Statement:
            - Effect: Allow
              Action:
                - ec2:StartInstances
                - ec2:StopInstances
              Resource: arn:aws:ec2:*:*:instance/*
            - Effect: Allow
              Action:
                - ec2:DescribeInstances
                - ec2:DescribeTags
                - ec2:DescribeInstanceStatus
              Resource: '*'
      CodeUri: ./lambda/EC2StopWeekDay.py
      Events:
        EC2StopWeekDayRule:
          Type: Schedule
          Properties:
            Name: EC2StopWeekDayRule
            Description: "EC2 Stop triggering every Week Day every 5 mins"
            Schedule: !Ref EC2StartStopWeekDaySchedule
            Enabled: true
      Description: >-
        EC2 Stop Week Day Time in HH:MM	(from tag : StopWeekDay)

  EC2StartWeekDayLambda:
    Type: AWS::Serverless::Function
    Properties:
      FunctionName: EC2StartWeekDay
      Runtime: python3.9
      MemorySize: 128
      Handler: EC2StartWeekDay.lambda_handler
      Timeout: 60
      ReservedConcurrentExecutions: 10
      Environment:
          Variables:
            REGION_TZ:
              Ref: RegionTZ
      Policies:
        - AWSLambdaBasicExecutionRole
        - Version: 2012-10-17
          Statement:
            - Effect: Allow
              Action:
                - ec2:StartInstances
                - ec2:StopInstances
              Resource: arn:aws:ec2:*:*:instance/*
            - Effect: Allow
              Action:
                - ec2:DescribeInstances
                - ec2:DescribeTags
                - ec2:DescribeInstanceStatus
              Resource: '*'
      CodeUri: ./lambda/EC2StartWeekDay.py
      Events:
        EC2StartWeekDayRule:
          Type: Schedule
          Properties:
            Name: EC2StartWeekDayRule
            Description: "EC2 Start triggering every Week Day every 5 mins"
            Schedule: !Ref EC2StartStopWeekDaySchedule
            Enabled: true
      Description: >-
        EC2 Start Week Day Time in HH:MM (from tag : StartWeekDay)

  EC2StopWeekEndLambda:
    Type: AWS::Serverless::Function
    Properties:
      FunctionName: EC2StopWeekEnd
      Runtime: python3.9
      MemorySize: 128
      Handler: EC2StopWeekEnd.lambda_handler
      Timeout: 60
      ReservedConcurrentExecutions: 10
      Environment:
          Variables:
            REGION_TZ:
              Ref: RegionTZ
      Policies:
        - AWSLambdaBasicExecutionRole
        - Version: 2012-10-17
          Statement:
            - Effect: Allow
              Action:
                - ec2:StartInstances
                - ec2:StopInstances
              Resource: arn:aws:ec2:*:*:instance/*
            - Effect: Allow
              Action:
                - ec2:DescribeInstances
                - ec2:DescribeTags
                - ec2:DescribeInstanceStatus
              Resource: '*'
      CodeUri: ./lambda/EC2StopWeekEnd.py
      Events:
        EC2StopWeekEndRule:
          Type: Schedule
          Properties:
            Name: EC2StopWeekEndRule
            Description: "EC2 Stop triggering every Week End every 5 mins"
            Schedule: !Ref EC2StartStopWeekEndSchedule
            Enabled: true
      Description: >-
        EC2 Stop Week End Time in HH:MM	(from tag : StopWeekEnd)

  EC2StartWeekEndLambda:
    Type: AWS::Serverless::Function
    Properties:
      FunctionName: EC2StartWeekEnd
      Runtime: python3.9
      MemorySize: 128
      Handler: EC2StartWeekEnd.lambda_handler
      Timeout: 60
      ReservedConcurrentExecutions: 10
      Environment:
          Variables:
            REGION_TZ:
              Ref: RegionTZ
      Policies:
        - AWSLambdaBasicExecutionRole
        - Version: 2012-10-17
          Statement:
            - Effect: Allow
              Action:
                - ec2:StartInstances
                - ec2:StopInstances
              Resource: arn:aws:ec2:*:*:instance/*
            - Effect: Allow
              Action:
                - ec2:DescribeInstances
                - ec2:DescribeTags
                - ec2:DescribeInstanceStatus
              Resource: '*'
      CodeUri: ./lambda/EC2StartWeekEnd.py
      Events:
        EC2StartWeekEndRule:
          Type: Schedule
          Properties:
            Name: EC2StartWeekEndRule
            Description: "EC2 Start triggering every Week End every 5 mins"
            Schedule: !Ref EC2StartStopWeekEndSchedule
            Enabled: true
      Description: >-
        EC2 Start Week End Time in HH:MM (from tag : StartWeekEnd)

Outputs:
  RegionTZOutput:
    Description: AWS Region Timezone
    Value: !Ref RegionTZ

  AWSRegionOutput:
    Description: AWS Region
    Value: !Ref AWS::Region