To make express web application modular use router factories:
Example-1
// Module: (greet.js)
let express = require('express');
module.exports = function(options = {}) { // Router factory
let router = express.Router();
router.get('/greet', (req, res, next) => {
res.end(options.greeting);
});
return router;
};
// Application: (app.js)
let express = require('express');
let greetMiddleware = require('./greet.js');
express()
.use('/api/v1/', greetMiddleware({ greeting:'Hi Morol' }))
.listen(3000);
// This will make your application modular, customisable and your code reusable.- http://localhost:3000/api/v1/greet
- Hi, Morol
Example-2
// Module: (greet.js)
const express = require('express');
module.exports = function(options = {}) { // Router factory
const router = express.Router();
// Get controller
const {service} = options;
router.get('/greet', (req, res, next) => {
res.end(
service.createGreeting(req.query.name || 'Stranger')
);
});
return router;
};
// Application: (app.js)
const express = require('express');
const greetMiddleware = require('./greet.js');
class GreetingService {
constructor(greeting = 'Hello') {
this.greeting = greeting;
}
createGreeting(name) {
return `${this.greeting}, ${name}!`;
}
}
express()
.use('/api/v1/service1', greetMiddleware({
service: new GreetingService('Hello'),
}))
.use('/api/v1/service2', greetMiddleware({
service: new GreetingService('Hi'),
}))
.listen(8080);