问题

export interface AWSTags {
  CreatedBy: string;
  Environment: EnvironmentMap;
  Name: string;
  OwnedBy: string;
  Platform: string;
  Product: string;
  Runbook: string;
  Service: string;
}

某些其他文件具有以下方法，用于返回与接口匹配的对象。

export const getAWSTags = (stackName: string, environment: EnvironmentMap, createdBy: string): AWSTags => ({
  CreatedBy: createdBy,
  Environment: environment,
  Name: stackName,
  OwnedBy: "owner",
  Platform: "platform",
  Product: "product",
  Runbook: "url",
  Service: `${stackName}-service`,
});

为了上下文，EnvironmentMap 是一个返回三个字符串之一的类型。

当我尝试将返回值分配给 AWS 标签时，它返回 2322。

readonly tags?: {
  [key: string]: string;
};

const app = new App();
const stack = new Stack(app, stackName, {
  env: {
    account: AWS.ACCOUNT,
    region: AWS.REGION,
  },
  tags: getAWSTags(stackName, environment, 'creator'),
});

类型 'AWSTags' 无法分配给类型 '{ [key: string]: string; }'。类型 'AWSTags' 中缺少类型 'string' 的索引签名。ts(2322)

解决这个问题或提供替代方法有哪些不同的途径？

编辑：这似乎可以去除错误，但不确定其有效性。

export interface AWSTags {
  [key: string]: string;
  CreatedBy: string;
  Environment: EnvironmentMap;
  Name: string;
  OwnedBy: string;
  Platform: string;
  Product: string;
  Runbook: string;
  Service: string;
}

谢谢

<details>
<summary>英文:</summary>

export interface AWSTags {
CreatedBy: string;
Environment: EnvironmentMap;
Name: string;
OwnedBy: string;
Platform: string;
Product: string;
Runbook: string;
Service: string;
}

Some other file has this method to return an object that matches the interface.

export const getAWSTags = (stackName: string, environment: EnvironmentMap, createdBy: string): AWSTags => ({
CreatedBy: createdBy,
Environment: environment,
Name: stackName,
OwnedBy: "owner",
Platform: "platform",
Product: "product",
Runbook: "url",
Service: ${stackName}-service,
});

For context, **EnvironmentMap** is a type that returns one of three strings.

When I try to assign the return value to AWS tags, which expects the following type, it returns 2322.

readonly tags?: {
[key: string]: string;
};

const app = new App();
const stack = new Stack(app, stackName, {
env: {
account: AWS.ACCOUNT,
region: AWS.REGION,
},
tags: getAWSTags(stackName, environment, 'creator'),
});

Type 'AWSTags' is not assignable to type '{ [key: string]: string; }'. Index signature for type 'string' is missing in type 'AWSTags'.ts(2322)

What are different approaches to solve this problem or alternatives?

**EDIT**: This seems to remove the error but not sure how valid is.

export interface AWSTags {
[key: string]: string;
CreatedBy: string;
Environment: EnvironmentMap;
Name: string;
OwnedBy: string;
Platform: string;
Product: string;
Runbook: string;
Service: string;
}

Thanks

</details>


# 答案1
**得分**: 2

问题在于，尽管最终的JS代码相同，从概念上讲，您将一个对象实例传递给了一个期望一个PoJo的东西。

基本上，这个：
```ts
export interface AWSTags {
  CreatedBy: string;
  Environment: EnvironmentMap;
  Name: string;
  OwnedBy: string;
  Platform: string;
  Product: string;
  Runbook: string;
  Service: string;
}

在TS中声明了你有一个与这个声明匹配的实例，但这并不意味着你的对象将仅由这些值组成。

为了解决这个问题，您需要从使用接口改为只有一个简单的类型：

export type AWSTags = {
  CreatedBy: string;
  Environment: EnvironmentMap;
  Name: string;
  OwnedBy: string;
  Platform: string;
  Product: string;
  Runbook: string;
  Service: string;
}

或者，如果您想保留接口，可以在将其注入到tags之前解构结果对象：

const stack = new Stack(app, stackName, {
  // ...
  tags: {...getAWSTags(stackName, environment, 'creator')},
});

export interface AWSTags {
  CreatedBy: string;
  Environment: EnvironmentMap;
  Name: string;
  OwnedBy: string;
  Platform: string;
  Product: string;
  Runbook: string;
  Service: string;
}

export type AWSTags = {
  CreatedBy: string;
  Environment: EnvironmentMap;
  Name: string;
  OwnedBy: string;
  Platform: string;
  Product: string;
  Runbook: string;
  Service: string;
}

const stack = new Stack(app, stackName, {
  // ...
  tags: {...getAWSTags(stackName, environment, 'creator')},
});