使用AWS-CDK打字稿更新单个堆栈时，RDS堆栈有问题

Question

由于使用aws-cdk创建和销毁vpc和rds实例需要花费时间，因此我们将它们分成了单独的堆栈。

VpcRds（取决于vpc）应用程序（取决于Rds）

起初，数据库实例命名存在问题。解决此问题后，我便开始在应用程序堆栈的管道上工作。

当我尝试部署我的应用程序堆栈时，它将运行在依赖关系中并进行检查。 Vpc没有更改，因此可以快速运行，而无需更新。应该对Rds堆栈说同样的话，但是它尝试在每次部署时更新堆栈。如果没有任何变化，那么它肯定会像Vpc堆栈一样工作并且不了解任何更改，因此请跳到下一个堆栈。

通过CloudFormation，我们可以通过将策略应用于堆栈来跳过或阻止任何不需要的更新。从我所见，这仍在开发中。

https://github.com/aws/aws-cdk/issues/3414https://github.com/aws/aws-cdk-rfcs/issues/72

[有一个使用setPolicy的示例，但是它正在创建一个新的cloudformation，并且我不太确定我将如何实现它。

    const app = new cdk.App();

const vpc = new VpcStack(app, "vpc", { env, appEnvironment: "staging" });
const rds = new RdsStack(app, "rds", {
  env,
  vpc: vpc.vpc,
  appEnvironment: "staging",
  masterPassword: dbPassword,
});
rds.addDependency(vpc);

const appStack = new AppStack(app, "app", {
  env,
  // configure the environments you want to setup.  The default is production &
  // staging, but for testing we'll just do staging.
  appEnvironments: ["staging"],
  environmentProps: {
    // per environment options go here
    staging: {
      vpc: vpc.vpc,
      db: {
        instance: rds.dbInstance,
        securityGroup: rds.securityGroup,
        username: rds.username,
        password: dbPassword,
      },
      ebOptions: {
        ec2KeyName: "App",
      },
    },
  },
});
appStack.addDependency(rds);
const pipeStack = new PipelineStack(app, "pipeline", {
  appEnvironment: "staging"
});
pipeStack.addDependency(appStack);

app.synth();

编辑

cdk差异输出

  cdk diff
Stack vpcStaging
There were no differences
Stack rdsStaging
Resources
[~] AWS::RDS::DBInstance instance instanceB**** replace
 ├─ [~] DBName (requires replacement)
 │   ├─ [-] rds_staging
 │   └─ [+] DBRds
 ├─ [~] DeletionPolicy
 │   ├─ [-] Delete
 │   └─ [+] Retain
 └─ [~] UpdateReplacePolicy
     ├─ [-] Delete
     └─ [+] Retain

Stack application
Template
[-] Description Description: Elasticbeanstalk setup for application

Security Group Changes
┌───┬─────────────────────────────────────────────┬─────┬─────────────────────────────────────────────┬─────────────────────────────────────────────┐
│   │ Group                                       │ Dir │ Protocol                                    │ Peer                                        │
├───┼─────────────────────────────────────────────┼─────┼─────────────────────────────────────────────┼─────────────────────────────────────────────┤
│ - │ {"Fn::ImportValue":"rdsStaging:ExportsOutput │ In  │ TCP {"Fn::ImportValue":"rdsStaging:ExportsOu │ ${prodsecurityGroupD*****.GroupId}        │
│   │ FnGetAttsecurityGroup88888GroupId***** │     │ tputFnGetAttinstance*****EndpointPort***** │                                             │
│   │ 1"}                                         │     │ *****"}                                     │                                             │
├───┼─────────────────────────────────────────────┼─────┼─────────────────────────────────────────────┼─────────────────────────────────────────────┤
│ + │ ${staging/securityGroup.GroupId}         │ Out │ Everything                                  │ Everyone (IPv4)                             │
├───┼─────────────────────────────────────────────┼─────┼─────────────────────────────────────────────┼─────────────────────────────────────────────┤
│ + │ {"Fn::ImportValue":"rdsStaging:ExportsOutput │ In  │ TCP {"Fn::ImportValue":"rdsStaging:ExportsOu │ ${staging/securityGroup.GroupId}         │
│   │ FnGetAttsecurityGroup*****GroupId***** │     │ tputFnGetAttinstance*****EndpointPort***** │                                             │
│   │ 1"}                                         │     │ *****"}                                     │                                             │
└───┴─────────────────────────────────────────────┴─────┴─────────────────────────────────────────────┴─────────────────────────────────────────────┘
(NOTE: There may be security-related changes not in this list. See https://github.com/aws/aws-cdk/issues/1299)

Resources
[-] AWS::EC2::SecurityGroup stagingsecurityGroup****** destroy
[-] AWS::EC2::SecurityGroupIngress stagingsecurityGrouprdsStagingsecurityGroup*****IndirectPortto***** destroy
[-] AWS::ElasticBeanstalk::Environment staging***** destroy
[+] AWS::EC2::SecurityGroup staging/securityGroup stagingsecurityGroup***** 
[+] AWS::EC2::SecurityGroupIngress staging/securityGroup/rdsStagingsecurityGroup*****:{IndirectPort} to stagingsecurityGrouprdsStagingsecurityGroup*****IndirectPortto***** 
[+] AWS::ElasticBeanstalk::Environment staging/staging staging***** 

Answer 1

好吧，正如我在评论中提到的那样，当从2个不同堆栈中导入另一个资源时，CDK在后台使用Fn::ImportValue。

从CDK Git-Hub source code：

 /**
   * The intrinsic function ``Fn::ImportValue`` returns the value of an output
   * exported by another stack. You typically use this function to create
   * cross-stack references. In the following example template snippets, Stack A
   * exports VPC security group values and Stack B imports them.
   * @param sharedValueToImport The stack output value that you want to import.
   * @returns a token represented as a string
   */
  public static importValue(sharedValueToImport: string): string {
    return new FnImportValue(sharedValueToImport).toString();
  }

如您所见，此函数返回以字符串表示的令牌。

因此，每次您运行cdk deploy时，都会生成新的令牌，并且看起来资源已更改。