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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.

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.

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.

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.

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.

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

Read this on the main serverless docs site¶