amazon-web-services - 云形成中的用户数据中的引用未得到解决

Question

我正在云形成中创建 EFS 卷，并尝试在启动模板的用户数据中引用该卷。

我尝试了在 CF 中使用 Ref 的多种语法，但每次都会遇到相同的错误。我实际上想用 EFS 做不同的事情，但发布的示例代码也不起作用

  ClusterFileSystem:
    Type: AWS::EFS::FileSystem
    Properties:
      Encrypted: true

ClusterLaunchTemplate:
  Type: AWS::EC2::LaunchTemplate
  DependsOn: ClusterFileSystem
  Properties:
    LaunchTemplateName: !Sub ${AWS::StackName}
    LaunchTemplateData:
      ImageId: !Ref 'AMIId'
      SecurityGroupIds: [!GetAtt 'ClusterSecurityGroup.GroupId']
      InstanceType: !Ref 'InstanceType'
      BlockDeviceMappings:
      - DeviceName: "/dev/xvda"
        Ebs:
          VolumeSize: "40"
          VolumeType: "gp2"
          Encrypted: true
      - DeviceName: "/dev/xvdcz"
        Ebs:
          VolumeSize: "22"
          VolumeType: "gp2"
          Encrypted: true
      IamInstanceProfile:
        Name: 'ECSHostInstanceProfile'
      Monitoring:
        Enabled: true
      KeyName: !Ref 'Key'
      UserData:
        Fn::Base64: !Sub |
          #!/bin/bash -xe

          function setup-efs () {

            {
              mkdir -p /ecs-resources/${AWS::StackName}/environment
              EFS_FILE_SYSTEM_ID= !Ref ClusterFileSystem
              echo ${EFS_FILE_SYSTEM_ID} >> /tmp/xyz.txt
            }

这是错误 -

模板格式错误:模板的资源 block 中存在未解析的资源依赖关系 [EFS_FILE_SYSTEM_ID] 调用 UpdateStack 操作时发生错误 (ValidationError):模板格式错误:模板的资源 block 中存在未解析的资源依赖关系 [EFS_FILE_SYSTEM_ID] - ”

Answer 1

您不需要在 !Sub 中使用 !Ref，要获得相同的行为，您只需引用 ${} 中的逻辑 ID 即可.

此外，您需要转义 ${EFS_FILE_SYSTEM_ID}，因为您想按字面打印它而不是让 !Sub 解析它。

UserData:
  Fn::Base64: !Sub |
    #!/bin/bash -xe

    function setup-efs () {

      {
        mkdir -p /ecs-resources/${AWS::StackName}/environment
        EFS_FILE_SYSTEM_ID= ${ClusterFileSystem}
        echo ${!EFS_FILE_SYSTEM_ID} >> /tmp/xyz.txt
      }

请注意 ${ClusterFileSystem} 的引用以及 EFS_FILE_SYSTEM_ID 大括号内的 !。

If you specify template parameter names or resource logical IDs, such as ${InstanceTypeParameter}, AWS CloudFormation returns the same values as if you used the Ref intrinsic function. If you specify resource attributes, such as ${MyInstance.PublicIp}, AWS CloudFormation returns the same values as if you used the Fn::GetAtt intrinsic function.

还有

To write a dollar sign and curly braces (${}) literally, add an exclamation point (!) after the open curly brace, such as ${!Literal}. AWS CloudFormation resolves this text as ${Literal}.

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