Express: 如何从不同的文件传递应用程序实例到路由？

假设您有一个名为“ controller”的文件夹。

在 app.js 中，你可以输入以下代码:

console.log("Loading controllers....");
var controllers = {};


var controllers_path = process.cwd() + '/controllers'


fs.readdirSync(controllers_path).forEach(function (file) {
if (file.indexOf('.js') != -1) {
controllers[file.split('.')[0]] = require(controllers_path + '/' + file)
}
});


console.log("Controllers loaded..............[ok]");

还有..。

router.get('/ping', controllers.ping.pinging);

在您的控制器文件夹中，您将拥有带有以下代码的文件“ ping.js”:

exports.pinging = function(req, res, next){
console.log("ping ...");
}

就是这个。

或者就这么做:

var app = req.app

在中间件中使用这些路由，像这样:

router.use( (req,res,next) => {
app = req.app;
next();
});

1. To make your db object accessible to all controllers without passing it everywhere: make an application-level middleware which attachs the db object to every req object, then you can access it within in every controller.

// app.js
let db = ...;  // your db object initialized
const contextMiddleware = (req, res, next) => {
req.db=db;
next();
};
app.use(contextMiddleware);

2. 避免到处传递应用程序实例，而是传递到应用程序所在位置的路由

// routes.js  It's just a mapping.
exports.routes = [
['/', controllers.index],
['/posts', controllers.posts.index],
['/posts/:post', controllers.posts.show]
];


// app.js
var { routes }    = require('./routes');
routes.forEach(route => app.get(...route));
// You can customize this according to your own needs, like adding post request

最后的 app.js:

// app.js
var express   = require('express');
var app       = express.createServer();


let db = ...;  // your db object initialized
const contextMiddleware = (req, res, next) => {
req.db=db;
next();
};
app.use(contextMiddleware);


var { routes }    = require('./routes');
routes.forEach(route => app.get(...route));


app.listen(3000, function() {
console.log('Application is listening on port 3000');
});

Another version: you can customize this according to your own needs, like adding post request

// routes.js  It's just a mapping.
let get = ({path, callback}) => ({app})=>{
app.get(path, callback);
}
let post = ({path, callback}) => ({app})=>{
app.post(path, callback);
}
let someFn = ({path, callback}) => ({app})=>{
// ...custom logic
app.get(path, callback);
}
exports.routes = [
get({path: '/', callback: controllers.index}),
post({path: '/posts', callback: controllers.posts.index}),
someFn({path: '/posts/:post', callback: controllers.posts.show}),
];


// app.js
var { routes }    = require('./routes');
routes.forEach(route => route({app}));

If you want to pass an app-instance to others in 节点-类型脚本 :

选择1: 在 import(进口时)的帮助下

//routes.ts
import { Application } from "express";
import { categoryRoute } from './routes/admin/category.route'
import { courseRoute } from './routes/admin/course.route';


const routing = (app: Application) => {
app.use('/api/admin/category', categoryRoute)
app.use('/api/admin/course', courseRoute)
}
export { routing }

然后导入并通过应用程序:

import express, { Application } from 'express';


const app: Application = express();
import('./routes').then(m => m.routing(app))

Option 2: With the help of class

// index.ts
import express, { Application } from 'express';
import { Routes } from './routes';




const app: Application = express();
const rotues = new Routes(app)
...

在这里，我们将访问路由类的构造函数中的应用程序

// routes.ts
import { Application } from 'express'
import { categoryRoute } from '../routes/admin/category.route'
import { courseRoute } from '../routes/admin/course.route';


class Routes {
constructor(private app: Application) {
this.apply();
}


private apply(): void {
this.app.use('/api/admin/category', categoryRoute)
this.app.use('/api/admin/course', courseRoute)
}
}


export { Routes }

var express = require('express');


var router = express.Router();


router.get('/', function(req, res, next) {
console.log(req.app); // use req.app to get app instance ;


res.render('index', { title: 'Express' });


});


module.exports = router;