如何在 TypeScript Express 中设置 cors()

Question

在我的一个项目中，这很有效：

import cors from "cors";

server.use(cors());

但目前，我的新项目中出现了这条可爱的打字稿警告消息：

  No overload matches this call.
  The last overload gave the following error.
    Argument of type '(req: Request<never, never, never, never>, res: { statusCode?: number | undefined; setHeader(key: string, value: string): any; end(): any; }, next: (err?: any) => any) => void' is not assignable to parameter of type 'RequestHandlerParams<ParamsDictionary, any, any, ParsedQs>'.
      Type '(req: Request<never, never, never, never>, res: { statusCode?: number | undefined; setHeader(key: string, value: string): any; end(): any; }, next: (err?: any) => any) => void' is not assignable to type 'RequestHandler<ParamsDictionary, any, any, ParsedQs>'.
        Types of parameters 'req' and 'req' are incompatible.
          Type 'Request<ParamsDictionary, any, any, ParsedQs>' is not assignable to type 'Request<never, never, never, never>'.
            Type 'ParamsDictionary' is not assignable to type 'never'.ts(2769)

然后我尝试设置自定义 cors 中间件并使用它：

import { NextFunction ,Request,Response} from 'express';

export const Cors=(req:Request, res:Response, next:NextFunction) => {
    res.setHeader("Access-Control-Allow-Origin", "*");
    res.setHeader(
      "Access-Control-Allow-Methods",
      "OPTIONS, GET, POST, PUT, PATCH, DELETE"
    );
    res.setHeader("Access-Control-Allow-Headers", "Content-Type, Authorization");
    if (req.method === "OPTIONS") {
      return res.sendStatus(200);
    }
    next();
  };

   server.use(Cors());

这次我又遇到了另一个可爱的错误：

没有重载与此调用匹配。最后一次超载出现以下错误。'Response | 类型的参数 undefined' 不可分配给类型为 'RequestHandlerParams<ParamsDictionary, any, any, ParsedQs>' 的参数。类型“未定义”不可分配给类型“RequestHandlerParams <ParamsDictionary，any，any，ParsedQs>”

Answer 1

这是因为 cors 库的通用类型存在一些歧义。我发现解决此问题的最简单方法就是显式指定该cors方法的请求类型。

import { Request } from "express";
import cors from "cors";

server.use(cors<Request>());

Answer 2

我找到了这个解决方案：

使用：

...
  "express": "^4.17.1",
  "@types/express": "^4.17.9",
...

将“.use(cors())”替换为

app.use((req: Request, res: Response, next: NextFunction) => {
  next();
}, cors({ maxAge: 84600 }));

来源：https ://github.com/DefinitelyTyped/DefinitelyTyped/issues/43909#issuecomment-743156647