using !Ref in second argument in SAM template

Question

The below code is giving me error:

NOTIFICATION_ARN: !Sub
    -  'arn:aws:sns:${AWS::Region}:${AWS::AccountId}:${stage}-${ServiceName}'
    -  ServiceName: !Ref ServiceName
    -  stage: !Ref Stage

error:Template error: One or more Fn::Sub intrinsic functions don't specify expected arguments. Specify a string as first argument, and an optional second argument to specify a mapping of values to replace in the string

How can I resolve this error? Stage is defined inside parameter section in sam template

Answer 1

You have one too many -. It should be:

NOTIFICATION_ARN: !Sub
    -  'arn:aws:sns:${AWS::Region}:${AWS::AccountId}:${stage}-${ServiceName}'
    -  ServiceName: !Ref ServiceName
       stage: !Ref Stage