express.js中的路由器优先级顺序 [英] Order of router precedence in express.js

问题描述

我想了解express.js中的顺序优先级。例如，如下代码

I would like to understand the order precedence in express.js. For example, as bellow code

var routes = require('./routes/index');
var users = require('./routes/users');
var api = require('./routes/api');


app.use('/api', api);
app.use('/users', users);

app.use('/:name', function(req, res, next) {    
    console.log('from app.js name:', req.params.name);   

    res.render('index', {
        title: req.params.name
    });
}, routes);

app.use('/', function(req, res, next) {   
    res.render('index', {
        title: 'MainPage'
    });
});

如果请求来自客户端localhost：3000 / api / abc和localhost：3000 / user / abc ，来自api和用户模块的响应。但是如果我提出了一个localhost：3000 / myName / xyz的请求，应用程序模块会返回一个响应。这个行为让我关注expressjs的优先级以及路由器模块的正确顺序。为什么路由器不会在api，users和参数：name之间混淆。请让我明白清楚表达方式和优先级。

If a request come from client localhost:3000/api/abc and localhost:3000/user/abc, the response from api and user module. But if I make a request like localhost:3000/myName/xyz, the app module return a response. This behavior let me concern about what is precedence of expressjs and what is correct order for router modules. Why routers do not confuse between actions "api", "users" and parameter ":name". Please let me understand clearly how express does and what is precedence.

推荐答案

订单先到先得。

在你的情况下，如果用户命中/ api，他将从api获得响应。但是如果在 / api 之前写入 /：name route， /：name 将用于 / api 请求。

In your case, if user hits /api, he will get response from api. But if you write /:name route before /api, /:name will serve for /api requests also.

案例1： / api 将提供 / api 的请求。

Case1: /api will serve requests for /api.

var routes = require('./routes/index');
var users = require('./routes/users');
var api = require('./routes/api');


app.use('/api', api);
app.use('/users', users);

app.use('/:name', function(req, res, next) {    
    console.log('from app.js name:', req.params.name);   

    res.render('index', {
        title: req.params.name
    });
}, routes);

app.use('/', function(req, res, next) {   
    res.render('index', {
        title: 'MainPage'
    });
});

Case2： /：name 请求 / api 和 / users

Case2: /:name serves requests for /api and /users

var routes = require('./routes/index');
var users = require('./routes/users');
var api = require('./routes/api');

app.use('/:name', function(req, res, next) {    
    console.log('from app.js name:', req.params.name);   

    res.render('index', {
        title: req.params.name
    });
}, routes);

app.use('/api', api);
app.use('/users', users);



app.use('/', function(req, res, next) {   
    res.render('index', {
        title: 'MainPage'
    });
});

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