node.js - Express + TypeScript : Create type inference for response. 本地人

Question

我想为我的 response.locals 添加类型。它用于将数据附加到您的请求-响应周期。

我尝试过的

// ./types/express/index.d.ts
declare global {
    declare namespace Express {
        interface Response {
            locals: {
                userId: number;
            };
        }
    }
}

// tsconfig.json
    "compilerOptions": {
        "typeRoots": ["./types"],
    }

myController.post("/", async (request, response) => {
     // Can't get type in my controller
    const { userId } = response.locals; // <- userId is any

目标:为我的 response.locals 变量获取正确的类型推断

版本:"express": "^4.17.1","@types/express": "^4.17.8","typescript": "^4.5.4"

Answer 1

在没有适当的 TypeScript 背景的情况下，我能够编译以下内容(经过反复试验):

import {Request, Response} from "express";
interface Locals extends Record<string, any> {
  userId: number;
}
interface MyResponse extends Response {
  locals: Locals;
}
export function middleware(request: Request, response: MyResponse) {
  const {userId} = response.locals;
  response.end(userId);
  return userId;
}

声明文件(.d.ts)包含:

export declare function middleware(request: Request, response: MyResponse): number;

因此正确推断了 number 类型。

当我在 express 中使用这个中间件功能时，它就起作用了。