AutoPublishAlias is not triggered for environment variable changes

[to-mc]

Description:

Changing or adding/removing environment variables for a function does not cause a new version to be published when using AutoPublishAlias.

Steps to reproduce the issue:

1. Deploy a SAM template with an AWS::Serverless::Function resource, with AutoPublishAlias set, and including an environment variable:

HelloWorldFunction:
    Type: AWS::Serverless::Function
    Properties:
      CodeUri: hello_world/
      Handler: app.lambda_handler
      Runtime: python3.8
      AutoPublishAlias: live
      Environment:
        Variables:
          TestKey: TestVal1

2. Change TestVal1 to TestVal2.
3. Run sam deploy .

Observed result:
The lambda function is updated with the new environment variable, but no new version is published, and the defined alias still points to the last published version.

Expected result:
A new function version is published, and the defined alias is updated to point to it.

[keetonian]

If the lambda function is invoked, does it have the old or new value for the environment variable?

[keetonian]

It looks like we can add the Environment dictionary to the hash that gets computed to determine if a new version needs to be published.

Section of code to update: https://github.com/awslabs/serverless-application-model/blob/master/versions/2016-10-31.md#awsserverlessapi

[to-mc]

When invoking via api gateway, the "old" version without my changed env var gets invoked.

@keetonian Did you paste the right url? Was expecting a link to a section of code but your link goes to documentation.

[dalumiller]

@cakepietoast @keetonian This is similar to the #1267 where environment variables stored in Secrets Manager that are changed don't trigger a new version of the lambda.

[to-mc]

Closing this as it was resolved with #1310.

[heyjustcode]

@cakepietoast this still doesn't work if the environment variable change was due to an updated value of a referenced parameter

      Environment:
        Variables:
          TEST_KEY_PARAM: !Ref ParamTestValue

[hoffa]

@heyjustcode adding AWS::LanguageExtensions to the Transform section of your template should help, see #2533.