如何为为响应添加属性的中间件编写TypeScript定义？

Question

我想用TypeScript将express-boom用于express。它缺乏打字，所以我想写自己的。只是让它编译是微不足道的。

这个中间件使用属性res（源自boom）来装饰boom module对象：

var express = require('express');
var boom = require('express-boom');

var app = express();

app.use(boom());

app.use(function (req, res) {
  res.boom.notFound(); // Responsds with a 404 status code
});

但是使用打字稿我需要施放它，因为http.ServerResponse和Express.Response都没有繁荣属性，当然：

return (<any>res).boom.badRequest('bla bla bla');

这是最干净的方法吗？哪些其他类型的中间件正在做类似的事情？

Answer 1

您可以使用其他一些Express中间件作为示例，例如Method-Override和它的type definitions。

作为一个更具体的示例，如果要将此.boom属性添加到响应对象，则只需创建一个包含以下内容的类型定义（express-boom.d.ts）：

declare namespace Express {
    interface Boom {
        // Add boom's properties in here
    }

    export interface Response {
        boom: Boom
    }
}

Answer 2

这是一个示例用法。希望这有助于某人。

包括express-boom.d.ts以及您的应用程序源文件。

有关示例用法，请参阅以下要点中的sample-usage.ts：

Gist: Type definitions for express-boom：

express-boom.d.ts

/**
 * Type definitions for express-boom
 * Definitions by: Sandeep K Nair <https://github.com/sandeepsuvit>
 * @author: Sandeep K Nair
 */
declare namespace Express {
    interface Boom {
        // Add boom's properties in here
        wrap: (error: Error, statusCode?: number, message?: string) => BoomError;
        create: (statusCode: number, message?: string, data?: any) => BoomError;

        // 4xx
        badRequest: (message?: string, data?: any) => BoomError;
        unauthorized: (message?: string, scheme?: any, attributes?: any) => BoomError;
        forbidden: (message?: string, data?: any) => BoomError;
        notFound: (message?: string, data?: any) => BoomError;
        methodNotAllowed: (message?: string, data?: any) => BoomError;
        notAcceptable: (message?: string, data?: any) => BoomError;
        proxyAuthRequired: (message?: string, data?: any) => BoomError;
        clientTimeout: (message?: string, data?: any) => BoomError;
        conflict: (message?: string, data?: any) => BoomError;
        resourceGone: (message?: string, data?: any) => BoomError;
        lengthRequired: (message?: string, data?: any) => BoomError;
        preconditionFailed: (message?: string, data?: any) => BoomError;
        entityTooLarge: (message?: string, data?: any) => BoomError;
        uriTooLong: (message?: string, data?: any) => BoomError;
        unsupportedMediaType: (message?: string, data?: any) => BoomError;
        rangeNotSatisfiable: (message?: string, data?: any) => BoomError;
        expectationFailed: (message?: string, data?: any) => BoomError;
        badData: (message?: string, data?: any) => BoomError;
        tooManyRequests: (message?: string, data?: any) => BoomError;

        // 5xx
        notImplemented: (message?: string, data?: any) => BoomError;
        badGateway: (message?: string, data?: any) => BoomError;
        serverTimeout: (message?: string, data?: any) => BoomError;
        gatewayTimeout: (message?: string, data?: any) => BoomError;
        badImplementation: (message?: string, data?: any) => BoomError;
    }

    export interface BoomError {
        data: any;
        reformat: () => void;
        isBoom: boolean;
        isServer: boolean;
        message: string;
        output: Output;
    }

    export interface Output {
        statusCode: number;
        headers: any;
        payload: any;
    }

    export interface Response {
        boom: Boom
    }
}

sample-usage.ts

export function someMiddleware(req: express.Request, res: express.Response, next: express.NextFunction) {
  // use it this way
  res.boom.forbidden("Failed to grant access to resource.");
  next();
}