ring-scheduler-3cx/template.yaml

AWSTemplateFormatVersion: "2010-09-09"
Transform: AWS::Serverless-2016-10-31
Description: 3CX Ring Group After-Hours Scheduler

Parameters:
  Timezone:
    Type: String
    Default: "America/New_York"
  ShiftTableName:
    Type: String
    Default: "afterhours-shifts"
    Description: DynamoDB table for Slack shift manager overrides

Globals:
  Function:
    Runtime: python3.12
    Timeout: 30
    MemorySize: 128

Resources:
  SchedulerFunction:
    Type: AWS::Serverless::Function
    Properties:
      FunctionName: 3cx-ring-group-scheduler
      Handler: src/handler.handler
      CodeUri: .
      Environment:
        Variables:
          SSM_PREFIX: /3cx-scheduler
          TZ: !Ref Timezone
          SHIFT_TABLE: !Ref ShiftTableName
      Policies:
        - Statement:
            - Effect: Allow
              Action:
                - ssm:GetParametersByPath
                - ssm:GetParameter
                - ssm:GetParameters
              Resource:
                - !Sub "arn:aws:ssm:${AWS::Region}:${AWS::AccountId}:parameter/3cx-scheduler"
                - !Sub "arn:aws:ssm:${AWS::Region}:${AWS::AccountId}:parameter/3cx-scheduler/*"
            - Effect: Allow
              Action:
                - kms:Decrypt
              Resource: "*"
              Condition:
                StringEquals:
                  "kms:ViaService": !Sub "ssm.${AWS::Region}.amazonaws.com"
            - Effect: Allow
              Action:
                - dynamodb:GetItem
              Resource:
                - !Sub "arn:aws:dynamodb:${AWS::Region}:${AWS::AccountId}:table/${ShiftTableName}"
      Events:
        # EST: 8am ET = 13:00 UTC (Nov-Mar)
        DailyScheduleEST:
          Type: Schedule
          Properties:
            Schedule: cron(0 13 ? * * *)
            Description: "Update 3CX ring group at 8am EST (Nov-Mar)"
            Enabled: true
        # EDT: 8am ET = 12:00 UTC (Mar-Nov)
        DailyScheduleEDT:
          Type: Schedule
          Properties:
            Schedule: cron(0 12 ? * * *)
            Description: "Update 3CX ring group at 8am EDT (Mar-Nov)"
            Enabled: true
        # Weekend 5pm — switch from day shift to night shift person
        # EST: 5pm ET = 22:00 UTC (Nov-Mar)
        WeekendEveningEST:
          Type: Schedule
          Properties:
            Schedule: cron(0 22 ? * SAT,SUN *)
            Description: "Switch to night shift on weekends at 5pm EST (Nov-Mar)"
            Enabled: true
        # EDT: 5pm ET = 21:00 UTC (Mar-Nov)
        WeekendEveningEDT:
          Type: Schedule
          Properties:
            Schedule: cron(0 21 ? * SAT,SUN *)
            Description: "Switch to night shift on weekends at 5pm EDT (Mar-Nov)"
            Enabled: true

  # SSM Parameters: create these manually via CLI before deploying.
  # See setup instructions in the deploy section below.

Outputs:
  FunctionArn:
    Value: !GetAtt SchedulerFunction.Arn
  FunctionName:
    Value: !Ref SchedulerFunction