AWS SAM: An error occurred (ValidationError) when calling the CreateChangeSet operation: Parameters: [IdentityNameParameter] must have values

Question

I want to get started with AWS SAM and I encounter this issue when trying to deploy to the AWS.

I am trying to deploy a 'Hello World!'-application that can be found here.

This is the error I encounter:

$ sam package --s3-bucket dolphin-code --s3-prefix prod --output-template-file packaged.yaml --region eu-central-1

Uploading to prod/de65208b144ad296cfdc39666a47ad1c  34671 / 34671.0  (100.00%)
Successfully packaged artifacts and wrote output template to file packaged.yaml.
Execute the following command to deploy the packaged template
sam deploy --template-file /builds/gitlab/dophin/apis/hello-world/packaged.yaml --stack-name 

$ sam deploy --template-file ./packaged.yaml --stack-name prod --capabilities CAPABILITY_IAM --region eu-central-1

Deploying with following values
===============================
Stack name                 : prod
Region                     : eu-central-1
Confirm changeset          : False
Deployment s3 bucket       : None
Capabilities               : ["CAPABILITY_IAM"]
Parameter overrides        : {}

Initiating deployment
=====================
Error: Failed to create changeset for the stack: prod, An error occurred (ValidationError) when 
calling the CreateChangeSet operation: Parameters: [IdentityNameParameter] must have values
ERROR: Job failed: exit code 1

For me, that seems to be an error in the AWS CLI and not in SAM directly, right?

Can anyone help me? Thanks in advance!

Answer 1

It seems that you are using a parameter in your sam template called "IdentityNameParameter", and it doesn't have a default value, thus Sam expects you to provide a value for it.

Either you set the value when you call your sam deploy using the flag --parameters-overrides

$ sam deploy --template-file ./packaged.yaml --stack-name prod --capabilities CAPABILITY_IAM --region eu-central-1 --parameter-overrides IdentityNameParameter=xyz

or give it a default value in your SAM template

Parameters: 
    IdentityNameParameter: 
      Type: String
      Default:"xyz"

You can read more about the sam deploy command here https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-cli-command-reference-sam-deploy.html