Pass in "Extra" Values

Feature Request

I’d like to be able to pass in values for additional properties to the MODULE types.

Example for a module named ACME::FOO::LogGroup::MODULE:

Parameters:
  FunctionName:
    Type: String

Resources:
  LogGroup:
    Type: AWS::Logs::LogGroup
    Properties:
      LogGroupName: !Sub /aws/lambda/${FunctionName}

Example use case of a default property as defined by CloudFormation/API:

LogGroup:
    Type: ACME::FOO::LogGroup::MODULE
    Properties:
      FunctionName: !Ref SomeLambdaFunction
      RetentionInDays: 3 << "Default" Property.

[taylorbartley]

@benbridts I really appreciate the extra info you included. To be clear, I do understand this was a very niche ask, and is probably outside the philosophical scope of modules in general. I mainly asked out of curiosity to see how far we could extend them. I’m satisfied with the dialog. Whoever’s in charge, please feel free to close or resolve this issue thank you!

[benbridts]

I understand the use case (it is very tempting to use modules to set your own defaults), but I personally would recommend against doing this.

• It makes it significantly harder to know the configuration of what will be deployed because you need to look at both the AWS documentation and the module documentation (or even source code).
• The ACME::FOO::LogGroup::MODULE might not be used in other modules you’re writing, and that’s hard to see form the top-level
• ACME::FOO::LogGroup::MODULE will definitely not be used in modules that are shared as Open Source projects
• Other Companies are running into this issue too

If you want more background on that, here are some links for possibly diving deeper

• I talked a bit about the problems I had with this approach in my talk at the CDK day (the talk is CDK-specific, but the ideas are more general).\
• Another example of people warning against this is the “L2.5” constructs warning in this CDK RFC.. You don’t need to read the whole thread, the linked comment and the comment after that have most of the information.