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CloudWatch Event

Simple event definition

This will enable your Lambda function to be called by an EC2 event rule. Please check the page of Event Types for CloudWatch Events.

yml

functions:
  myCloudWatch:
    handler: myCloudWatch.handler
    events:
      - cloudwatchEvent:
          event:
            source:
              - 'aws.ec2'
            detail-type:
              - 'EC2 Instance State-change Notification'
            detail:
              state:
                - pending

Enabling / Disabling

Note: cloudwatchEvent events are enabled by default.

This will create and attach a disabled cloudwatchEvent event for the myCloudWatch function.

yml

functions:
  myCloudWatch:
    handler: myCloudWatch.handler
    events:
      - cloudwatchEvent:
          event:
            source:
              - 'aws.ec2'
            detail-type:
              - 'EC2 Instance State-change Notification'
            detail:
              state:
                - pending
          enabled: false

Specify Input or Inputpath

You can specify input values to the Lambda function.

yml

functions:
  myCloudWatch:
    handler: myCloudWatch.handler
    events:
      - cloudwatchEvent:
          event:
            source:
              - 'aws.ec2'
            detail-type:
              - 'EC2 Instance State-change Notification'
            detail:
              state:
                - pending
          input:
            key1: value1
            key2: value2
            stageParams:
              stage: dev
      - cloudwatchEvent:
          event:
            source:
              - 'aws.ec2'
            detail-type:
              - 'EC2 Instance State-change Notification'
            detail:
              state:
                - pending
          inputPath: '$.stageVariables'
      - cloudwatchEvent:
          event:
            source:
              - 'aws.ec2'
            detail-type:
              - 'EC2 Instance State-change Notification'
            detail:
              state:
                - pending
          inputTransformer:
            inputPathsMap:
              eventTime: '$.time'
            inputTemplate: '{"time": <eventTime>, "key1": "value1"}'

Specifying a Description

You can also specify a CloudWatch Event description.

yml

functions:
  myCloudWatch:
    handler: myCloudWatch.handler
    events:
      - cloudwatchEvent:
          description: 'CloudWatch Event triggered on EC2 Instance pending state'
          event:
            source:
              - 'aws.ec2'
            detail-type:
              - 'EC2 Instance State-change Notification'
            detail:
              state:
                - pending

Specifying a Name

You can also specify a CloudWatch Event name. Keep in mind that the name must begin with a letter; contain only ASCII letters, digits, and hyphens; and not end with a hyphen or contain two consecutive hyphens. More information here.

yml

functions:
  myCloudWatch:
    handler: myCloudWatch.handler
    events:
      - cloudwatchEvent:
          name: 'my-cloudwatch-event-name'
          event:
            source:
              - 'aws.ec2'
            detail-type:
              - 'EC2 Instance State-change Notification'
            detail:
              state:
                - pending