Template error: instance of Fn::GetAtt references undefined resource EventHandlerLambdaFunction

Question

Can anyone help me find what's wrong?

I'm importing this cloudformation resources in my serverless yml. This is my function config:

Resources:
  eventHandler:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: eventLambda/
      Handler: dist/app.eventHandler
      Runtime: nodejs12.x
      FunctionName: eventHandler

This where I'm referencing it:

eventSourceRule:
    Type: 'AWS::Events::Rule'
    Properties:
      Name: eventSourceRule
      EventBusName: omnibus-${self:custom.stage}
      EventPattern: |
        {
          "source": ["op.api"]
        }
      RetryPolicy:
        MaximumRetryAttempts: 5
        MaximumEventAgeInSeconds: 900
      DeadLetterConfig:
        Type: SQS
        QueueLogicalId: EBRuleDLQ
      Targets:
        - Arn:
            Fn::GetAtt:
              - 'EventHandlerLambdaFunction'
              - 'Arn'
          Id: 'eventSourceRule'

Notice that I've already tried eventHandler and EventHandler and none of these worked. That's the error I'm receiving:

The CloudFormation template is invalid: Template error: instance of Fn::GetAtt references undefined resource EventHandlerLambdaFunction

Answer 1

I think you have to add the logical name of resource.
Replace EventHandlerLambdaFunction to actual resource name eventHandler.
You are not using the logical name of your Lambda resource you have defined.

---

You can try using the simple YAML syntax:

Targets:
  - Arn: !GetAtt eventHandler.Arn

Reference: Fn::GetAtt AWS Documentation