将安全 SSM 参数传递到嵌套的 CloudFormation 堆栈

Pass secure SSM parameter to a nested CloudFormation stack

我有一个嵌套的 CloudFormation 堆栈模板,用于描述数据库及其相关资源。我需要为各种环境创建多个数据库(例如 stageqaprod)。

我将每个环境的数据库密码作为安全字符串存储在 SSM 参数存储中,例如:

我尝试解析父模板中的 SSM 参数并将其传递给嵌套堆栈,但它似乎不起作用。

# parent.template

StageDatabaseStack:
  Type: AWS::CloudFormation::Stack
  Properties:
    TemplateURL: "…/database.template"
    Parameters:
      DatabasePassword: '{{resolve:ssm-secure:/acme/stage/DB_PASSWORD:1}}'

QaDatabaseStack:
  Type: AWS::CloudFormation::Stack
  Properties:
    TemplateURL: "…/database.template"
    Parameters:
      DatabasePassword: '{{resolve:ssm-secure:/acme/qa/DB_PASSWORD:1}}'

ProdDatabaseStack:
  Type: AWS::CloudFormation::Stack
  Properties:
    TemplateURL: "…/database.template"
    Parameters:
      DatabasePassword: '{{resolve:ssm-secure:/acme/prod/DB_PASSWORD:1}}'


# database.template

AWSTemplateFormatVersion: "2010-09-09"

Parameters:
  DatabasePassword:
    Type: String

Resources:
  Database:
    Type: AWS::RDS::DBInstance
    Properties:
      MasterUserPassword: !Ref DatabasePassword

这种方法给我一个错误:

An error occurred (ValidationError) when calling the CreateStack operation: SSM Secure reference is not supported in: [AWS::CloudFormation::Stack/Properties/Parameters/DatabasePassword]


根据the docs,也可以将密码参数定义为特殊的AWS::SSM::Parameter::Value<String>类型,但声明:

AWS CloudFormation does not support defining template parameters as SecureString Systems Manager parameter types.

我确实尝试过使用它,但它给了我一个错误:

Parameters [/acme/stage/DB_PASSWORD] referenced by template have types not supported by CloudFormation.


那么,在这种情况下,我如何实际将安全数据库密码传递给数据库资源?我想使用一个 CloudFormation 模板来管理所有三个数据库及其相关资源。

尝试:

'{{resolve:ssm-secure:/acme/stage/DB_PASSWORD:1}}'

即带撇号。见 YAML examples in the documentation:

  MyS3Bucket:
    Type: 'AWS::S3::Bucket'
    Properties:
      AccessControl: '{{resolve:ssm:S3AccessControl:2}}' 

我发现将安全 SSM 参数传递给嵌套堆栈的唯一方法是将其作为字符串传递,而不是尝试使用更合理的 AWS::SSM::Parameter::Value<String> 然后在通过使用 !Sub 函数构建动态引用来嵌套堆栈。

这是一个工作示例:

# parent.template

StageDatabaseStack:
  Type: AWS::CloudFormation::Stack
  Properties:
    Parameters:
      DatabasePasswordSsmKey: "/acme/stage/DB_PASSWORD:1"

ProdDatabaseStack:
  Type: AWS::CloudFormation::Stack
  Properties:
    Parameters:
      DatabasePasswordSsmKey: "/acme/prod/DB_PASSWORD:1"
# database.template

Parameters:
  DatabasePasswordSsmKey:
    Description: SSM property key for database password
    Type: String

Database:
  Type: AWS::RDS::DBInstance
  Properties:
    MasterUserPassword: !Sub "{{resolve:ssm-secure:${DatabasePasswordSsmKey}}}"