AWS Lambda scheduled event source via cloudformation

Question

I already have my lambda / roles defined in cloudformation and would love to also use it to add a scheduled eventsources ... are there any docs or examples around ?

grosser · Accepted Answer · 2017-01-01T22:19:26.383

42

Use Aws::Event::Rule with a ScheduleExpression and a AWS::Lambda::Permission

// rule to periodically call the lambda
"TagWatcherRule": {
  "Type": "AWS::Events::Rule",
  "Properties": {
    "ScheduleExpression": "rate(10 minutes)",
    "Targets": [
      {
        "Id": "TagWatcherScheduler",
        "Arn": {
          "Fn::GetAtt": [
            "TagWatcherFunction",
            "Arn"
          ]
        }
      }
    ]
  }
},
// role may call the lambda
"InvokeLambdaPermission": {
  "Type": "AWS::Lambda::Permission",
  "Properties": {
    "FunctionName": {
      "Fn::GetAtt": [
        "TagWatcherFunction",
        "Arn"
      ]
    },
    "Action": "lambda:InvokeFunction",
    "Principal": "events.amazonaws.com",
    "SourceArn": {
      "Fn::GetAtt": [
        "TagWatcherRule",
        "Arn"
      ]
    }
  }
}

edited Jan 01 '17 at 22:19

answered Apr 21 '16 at 17:27

grosser

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1

According to the docs, ScheduleExpression needs to be plural minutes not minute. http://docs.aws.amazon.com/AmazonCloudWatch/latest/DeveloperGuide/ScheduledEvents.html – timmah.faase Apr 24 '16 at 00:43
@timmah.faase Not true? "Valid values: minute | minutes | hour | hours | day | days" – dsvensson Dec 20 '16 at 15:06
11

You're allowed singular on "1", e.g. "1 minute", but must use plural otherwise, e.g. "10 minutes". Grammar is enforced! – helloPiers Dec 31 '16 at 21:09
1

I wish I could upvote this a bunch of times. I'm certain you just saved me hours of my life. – Bryan Slatner Jun 05 '18 at 20:10
How can we pass custom input to lambda function through event rule? – nff Mar 08 '19 at 09:54
@nff you can pass custom input by adding an attribute to the Target definition: so in this example it would be ```{ "Id": "TagWatcherScheduler", "Arn": { "Fn::GetAtt": [ "TagWatcherFunction", "Arn" ] }, "Input": "{'hello': 'world'}" }``` – cynicaljoy May 16 '19 at 17:43

score 11 · Answer 2 · answered May 27 '16 at 02:15

I solved same problem.

"RoleForLambdaStopEC2Instances" : {
  "Type": "AWS::IAM::Role",
  "Properties": {
    "AssumeRolePolicyDocument": {
      "Version": "2012-10-17",
      "Statement": [
        {
          "Sid": "",
          "Effect": "Allow",
          "Principal": {
            "Service": "lambda.amazonaws.com"
          },
          "Action": "sts:AssumeRole"
        }
      ]
    },
    "Policies": [
      {
        "PolicyName": "LambdaStopEC2InstancesPolicy",
        "PolicyDocument": {
          "Version": "2012-10-17",
          "Statement": [
            {
              "Effect": "Allow",
              "Action": [
                "logs:CreateLogGroup",
                "logs:CreateLogStream",
                "logs:PutLogEvents",
                "ec2:StopInstances"
              ],
              "Resource": [
                "arn:aws:logs:*:*:*",
                "arn:aws:ec2:*"
              ]
            }
          ]
        }
      }
    ],
    "Path": "/"
  }
},
"LambdaStopEC2Instances": {
  "Type": "AWS::Lambda::Function",
  "Properties": {
    "Code": {
      "S3Bucket": "XXXXXXXXXXXXXXXXX",
      "S3Key": "XXXXXXXXXXXXXXXXXX"
    },
    "Handler": "stopEC2Instances.handler",
    "Role": { "Fn::GetAtt" : ["RoleForLambdaStopEC2Instances", "Arn"] },
    "Runtime": "nodejs4.3",
    "Timeout": "5"
  }
},
"StopEC2InstancesRule": {
  "Type" : "AWS::Events::Rule",
  "Properties" : {
    "Name" : "StopEC2Instances",
    "ScheduleExpression" : "cron(0 13 ? * MON-FRI *)",
    "State": "ENABLED",
    "Targets": [{
      "Arn": { "Fn::GetAtt": ["LambdaStopEC2Instances", "Arn"] },
      "Id": "stopEC2Instances"
    }]
  }
},
"LambdaInvokePermission": {
  "Type": "AWS::Lambda::Permission",
  "Properties": {
    "FunctionName" : { "Fn::GetAtt" : ["LambdaStopEC2Instances", "Arn"] },
    "Action": "lambda:InvokeFunction",
    "Principal": "events.amazonaws.com",
    "SourceAccount": { "Ref" : "AWS::AccountId" },
    "SourceArn": { "Fn::GetAtt": ["StopEC2InstancesRule","Arn"] }
  }
}

In LambdaInvokePermission the SourceAccount property stopped it running for me — jhanson, Jan 26 '17 at 15:33
same as @jhanson, I had to remove the SourceArn line in LambdaInvokePermission — grasshopper, Jul 23 '20 at 12:38

score 10 · Answer 3 · answered Nov 22 '19 at 06:04

The YAML Version

ScheduledRule: 
  Type: AWS::Events::Rule
  Properties: 
    Description: "ScheduledRule"
    ScheduleExpression: "rate(10 minutes)"
    State: "ENABLED"
    Targets: 
      - 
        Arn: 
          Fn::GetAtt: 
            - "LambdaFunction"
            - "Arn"
        Id: "TargetFunctionV1"
PermissionForEventsToInvokeLambda: 
  Type: AWS::Lambda::Permission
  Properties: 
    FunctionName: 
      Ref: "LambdaFunction"
    Action: "lambda:InvokeFunction"
    Principal: "events.amazonaws.com"
    SourceArn: 
      Fn::GetAtt: 
        - "ScheduledRule"
        - "Arn"

Jason · Answer 4 · 2016-05-19T14:11:24.270

Unfortunately, configuring scheduled event sources for lambda functions is currently not supported by CloudFormation. You will need to deploy your lambda using CloudFormation and then manually configure your scheduled events.

CloudFormation does support an AWS::Lambda::EventSourceMapping resource type. However, this resource is limited configuring Kinesis or DynamoDB streams, so this is likely not helpful to you.

http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-lambda-eventsourcemapping.html

**Update - as of April 2016, this is now supported using CloudWatch Events - https://aws.amazon.com/about-aws/whats-new/2016/04/amazon-cloudwatch-events-now-supported-in-aws-cloudformation-templates/

score 4 · Answer 5 · answered Apr 20 '16 at 03:50

As of this week (18 April 2016) it is now possible to add a scheduled CloudWatch event rule that will trigger your Lambda function.

The AWS::Event::Rule has a ScheduleExpression field for the cron-style schedule and a Targets array which can accept a Lambda function ARN.

score 1 · Answer 6 · edited Aug 23 '17 at 02:14

1

AWS supports periodic run through sourcedetails.

 EventSource: "aws.config"
 MaximumExecutionFrequency: Twelve_Hours
 MessageType: "ScheduledNotification"

edited Aug 23 '17 at 02:14

Nathan Tuggy

2,237
27
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answered Aug 23 '17 at 01:41

Ripon Banik

151
2
4

score 1 · Answer 7 · answered May 29 '20 at 19:37

If you use function name as

"FunctionName": {
      "Fn::GetAtt": [
        "TagWatcherFunction",
        "Arn"
      ]
    }

and you not specify the function then it'll throw you "Template is not valid: Template error: instance of Fn::GetAtt references undefined resource TagWatcherFunction"

So instead of function name you can directly specify the "lambda ARN". you can see example below

"TagWatcherRule": {
  "Type": "AWS::Events::Rule",
  "Properties": {
    "ScheduleExpression": "rate(10 minutes)",
    "Targets": [
      {
        "Id": "TagWatcherScheduler",
        "Arn": {
          "Fn::GetAtt": [
            "TagWatcherFunction",
            "Arn"
          ]
        }
      }
    ]
  }
},
// role may call the lambda
"InvokeLambdaPermission": {
  "Type": "AWS::Lambda::Permission",
  "Properties": {
    "FunctionName": "arn:aws:lambda:<region>:<awsid>:function:<lambd name>",
    "Action": "lambda:InvokeFunction",
    "Principal": "events.amazonaws.com",
    "SourceArn": {
      "Fn::GetAtt": [
        "TagWatcherRule",
        "Arn"
      ]
    }
  }
}

AWS Lambda scheduled event source via cloudformation

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