Severless Error: The CloudFormation template is invalid: Template error: instance of Fn::GetAtt references undefined resource name-of-role

Question

I am trying to deploy a service to AWS using serverless framework and keep getting the following error: Error: The CloudFormation template is invalid: Template error: instance of Fn::GetAtt references undefined resource dev-example

Here are the relevant parts of my serverless.yml file:

service: example 

provider:
  name: aws
  runtime: python3.7
  memorySize: 128
  logRetentionInDays: 1
  timeout: 300 
  role: ${opt:stage}-${self:service}

  resources:
    Resources:
      dev-example:
        Type: AWS::IAM::Role
        Properties:
          RoleName: ${opt:stage}-${self:service}-role
          AssumeRolePolicyDocument:
            Version: '2020-05-13'
            Statement:
              - Effect: Allow
                Principal:
                  Service:
                    - lambda.amazonaws.com
                Action: 'sts:AssumeRole' 
          ManagedPolicyArns:
            - arn:aws:iam::aws:policy/service-role/AWSLambdaVPCAccessExecutionRole
            - arn:aws:iam::aws:policy/AmazonRDSDataFullAccess
            - arn:aws:iam::aws:policy/AmazonS3ReadOnlyAccess
            - arn:aws:iam::aws:policy/service-role/AWSLambdaRole
          Policies:
            - PolicyName: ${opt:stage}-${self:service}-policies
              PolicyDocument:
                Version: '2020-05-13'
                Statement:
                  - Effect: Allow
                    Action: 
                      - logs:CreateLogGroups
                      - logs:CreateLogStream
                      - logs:PutLogEvents
                    Resource:
                      - 'Fn::Join':
                        - ':'
                        -
                          - 'arn:aws:logs'
                          - Ref: 'AWS::Region'
                          - Ref: 'AWS::AccountId'
                          - 'log-group:/aws/lambda/*:*:*' 

Any insights as to what is causing this error would be great!

The resources format for the custom IAM Role was created using the template here: https://www.serverless.com/framework/docs/providers/aws/guide/iam/

Answer 1

I would suggest taking a look at the serverless-pseudo-parameters plug in that can help you simplify the configurative of some of those AWS variable parameters and thereby eliminate the error you are having

https://www.serverless.com/plugins/serverless-pseudo-parameters/

Answer 2

In this case you just give it the name of the resource:

provider:
  name: aws
  runtime: python3.7
  memorySize: 128
  logRetentionInDays: 1
  timeout: 300 
  role: dev-example

When the role is created it will be named what you have under RoleName with the substituted values.