amazon-web-services - CloudFormation 可选映射属性 - DeadLetterQueue

Question

仅当 Env=ppd 或 Env=prod 时，我才需要在“AWS::Serverless::Function”中创建 DeadLetterQueue 属性

Conditions:
  IsPpdOrPrdEnv: !Or [!Equals [!Ref "Env", ppd], !Equals [!Ref "Env", prod]]
<...>
Resources:
  <...>
  TestFunction:
    Type: 'AWS::Serverless::Function'
    Properties:
      FunctionName: !Sub '${Env}-Test-Function'
      DeadLetterQueue: 
        TargetArn: !If [IsPpdOrPrdEnv, !Ref TestSNSTopic, !Ref "AWS::NoValue"]
        Type: !If [IsPpdOrPrdEnv, SNS, !Ref "AWS::NoValue"]
  <...>

错误:

Transform AWS::Serverless-2016-10-31 failed with: Internal transform failure.

我也尝试过:

     DeadLetterQueue: 
        !If
          - IsPpdOrPrdEnv
          - 
            TargetArn: !Ref TestSNSTopic
            Type: SNS
          - !Ref "AWS::NoValue"

错误:

Transform AWS::Serverless-2016-10-31 failed with: Invalid Serverless Application Specification document. Number of errors found: 1. Resource with id [TestFunction] is invalid. 'DeadLetterQueue' requires Type and TargetArn properties to be specified.

请问有什么建议吗？

Answer 1

这似乎是 SAM 的错误/限制。 github 中存在 Unresolved 问题( here 和 here )，它们描述了您所遇到的情况。

由于这两个问题都尚未解决，因此它们尚未解决。提供的唯一解决方法是:

We ended up needing to add a (manual or scripted) pre-deploy step that just removes the entire [DeadLetterQueue] config part if a [DeadLetterQueue] isn't desired.