在 TemplateURL 创建中使用 !Sub 时出现问题

Question

尝试部署嵌套的 Cloudformation 堆栈。如果我硬编码TemplateURL如下，工作正常-

AWSTemplateFormatVersion: '2010-09-09'
Resources:
  MyStack:
    Type: AWS::CloudFormation::Stack
    Properties:
      TemplateURL: https://s3.eu-west-1.amazonaws.com/my-bucket/my-template.yml

但是一旦我开始在TemplateURL例如内进行任何字符串替换

AWSTemplateFormatVersion: '2010-09-09'
Resources:
  MyStack:
    Type: AWS::CloudFormation::Stack
    Properties:
      TemplateURL: !Sub "https://s3.#{AWS::Region}.amazonaws.com/my-bucket/my-template.yml"

然后在部署时我得到 -

AWS::CloudFormation::Stack | CREATE_FAILED | TemplateURL must be an Amazon S3 URL.

I have tried different flavours of !Sub and Fn::Sub, and with using custom defined variables rather than AWS::Region, but always the same result :-/

What am I doing wrong here ?? TIA.

Answer 1

You should use ${AWS::Region} instead of #{AWS::Region} (dollar sign instead of hashtag)

A string with variables that AWS CloudFormation substitutes with their associated values at runtime. Write variables as ${MyVarName} [...]

来源：https : //docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/intrinsic-function-reference-sub.html