在 sam 模板中重用一个值

Question

I'm probably missing something very obvious, but I can't find a way of just setting a value that I want to reuse. For instance - I have a sam template that creates a bunch of database tables - I want them to all have the same settings - and I want those settings to depend on whether it's production or not.

so at the moment I do

Resources:
    firstTable:
         Type: AWS::DynamoDb::Table
         ...
         DeletionPolicy:   !If[ isProduction, Retain, Delete ]
    secondTable:
         Type: AWS::DynamoDb::Table
         DeletionPolicy:   !If[ isProduction, Retain, Delete ]

in the perfect world, I'd want to say something like "every dynamodb table defined in this template should have this list of settings:" - but I suspect that's not possible, but what I think IS possible - I want to somehow be able to say something like:

somewhere:
   deletion_policy_value: !If[ isProduction, Retain, Delete ]

...

   firstTable:
         Type: AWS::DynamoDb::Table
         ...
         DeletionPolicy:   deletion_policy_value

but none of parameters, conditionals globals or environment variables seem to fit - ie I want to define a custom variable that exists only for the life of the template - environment variables seem to exist in the actual cloudformation script - which is NOT what I want (I think)

Answer 1

Sadly its not possible. You would have to develop your own macro to create such substitutions.