Node.js 为原型函数添加类型

我在节点模块中有一个JavaScript

函数

，如下所示（简化）：

index.js

：

var BadRequestError = require('./error')

Guard.prototype = {

  /**
   *
   * @param {String} property
   * @return {_middleware}
   */
  check: function (property) {
    const _middleware = function _middleware (req, res, next) {
      const ok = property === 'ping'
      next(!ok ? new BadRequestError('doing_it_wrong', { message: `you're doing it wrong`}) : null)
    }

    return _middleware
  }
}

module.exports = function (options) {
  return new Guard(options)
}

module.exports = function BadRequestError (code, error) {
  Error.captureStackTrace(this, this.constructor)

  this.name = this.constructor.name
  this.message = error.message

  this.code = code
  this.status = 400
  this.inner = error
}

util.inherits(module.exports, Error)

var guard = require('../index')({
  someProperty: 'test',
})
var req = {}
guard.check('ping')(req, res, function (err) {
  assert.deepStrictEqual(null, err)
})

error.js

：

var BadRequestError = require('./error')

Guard.prototype = {

  /**
   *
   * @param {String} property
   * @return {_middleware}
   */
  check: function (property) {
    const _middleware = function _middleware (req, res, next) {
      const ok = property === 'ping'
      next(!ok ? new BadRequestError('doing_it_wrong', { message: `you're doing it wrong`}) : null)
    }

    return _middleware
  }
}

module.exports = function (options) {
  return new Guard(options)
}

module.exports = function BadRequestError (code, error) {
  Error.captureStackTrace(this, this.constructor)

  this.name = this.constructor.name
  this.message = error.message

  this.code = code
  this.status = 400
  this.inner = error
}

util.inherits(module.exports, Error)

var guard = require('../index')({
  someProperty: 'test',
})
var req = {}
guard.check('ping')(req, res, function (err) {
  assert.deepStrictEqual(null, err)
})

用法如下：

test.js

：

var BadRequestError = require('./error')

Guard.prototype = {

  /**
   *
   * @param {String} property
   * @return {_middleware}
   */
  check: function (property) {
    const _middleware = function _middleware (req, res, next) {
      const ok = property === 'ping'
      next(!ok ? new BadRequestError('doing_it_wrong', { message: `you're doing it wrong`}) : null)
    }

    return _middleware
  }
}

module.exports = function (options) {
  return new Guard(options)
}

module.exports = function BadRequestError (code, error) {
  Error.captureStackTrace(this, this.constructor)

  this.name = this.constructor.name
  this.message = error.message

  this.code = code
  this.status = 400
  this.inner = error
}

util.inherits(module.exports, Error)

var guard = require('../index')({
  someProperty: 'test',
})
var req = {}
guard.check('ping')(req, res, function (err) {
  assert.deepStrictEqual(null, err)
})

我尝试使用几种方法为其创建TypeScript打字，但似乎都不起作用：

index.d.ts

：

export declare interface IGuardOptions {
    property: string
}

通过

class

声明导出：

export declare class Guard  {
    constructor(options: IGuardOptions)
    check(required: string | Array<string>): any
}

export declare interface Guard {
    check(property: string): any
}
export declare type GuardConstructor = new(options: IGuardOptions) => Guard

---

不清楚“不工作”是什么意思，因为您没有编写任何Typescript代码，只是声明，所以我假设

test.js

应该是

test.ts

来回答您的问题

您将希望在原始Javascript源代码旁边创建一个类型声明（就像您已经做的那样），但是您需要确保该结构与原始模块等效。Typescript声明表明存在多个导出，而Javascript实现只有一个导出

误差d.ts

declare class BadRequestError extends Error {
    code: string;
    status: number;
    inner: Error;

    constructor(code: string, error: Error);
}

export = BadRequestError;

索引d.ts

import {Handler} from 'express';

declare interface GuardOptions {
    someProperty: string;
}

declare class Guard {
    constructor(options: GuardOptions);

    check(property: string): Handler;
}

declare function guardFactory(options: GuardOptions): Guard;

export = guardFactory;

test.ts

import {Request, Response} from 'express';

import guardFactory = require('./index');

const guard = guardFactory({
    someProperty: 'test',
});

const middleware = guard.check('ping');

const req = {} as Request;
const res = {} as Response;
const next = function (err) {
    assert.deepStrictEqual(null, err);
};

middleware(req, res, next);

---

您的问题可能与以下事实有关：您正在使用类型完全不同的

BadRequestError

覆盖

Guard

“factory”导出。BadRequestError是一个不同的文件，有点令人困惑，如果它与您的问题无关，您能否将其删除？在哪里实现类型声明？也在一个单独的文件中？对不起，现在应该更好了。

BadRequestError

可能在

middleware

中返回

Guard

类在哪里声明？这也是一个单独的文件吗？“不工作”并不意味着WebStorm和VS代码都没有为键入提供代码完成、语法突出显示或验证。谢谢你的耐心。