在express中的root之后使用可选参数传递路由控制? [英] Passing route control with optional parameter after root in express?

问题描述

我正在开发一个简单的 url-shortening 应用程序，并有以下快速路线:

I'm working on a simple url-shortening app and have the following express routes:

app.get('/', function(req, res){
  res.render('index', {
    link: null
  });
});

app.post('/', function(req, res){
  function makeRandom(){
    var text = "";
    var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";

    for( var i=0; i < 3 /*y u looking at me <33??*/; i++ )
      text += possible.charAt(Math.floor(Math.random() * possible.length));
    return text;
  }
  var url = req.body.user.url;
  var key = makeRandom();
  client.set(key, url);
  var link = 'http://50.22.248.74/l/' + key;
  res.render('index', {
    link: link
  });
  console.log(url);
  console.log(key);
});

app.get('/l/:key', function(req, res){
  client.get(req.params.key, function(err, reply){
    if(client.get(reply)){
      res.redirect(reply);
    }
    else{
      res.render('index', {
        link: null
      });
    }
  });
});

我想从我的路由中删除 /l/ (以使我的 url 更短)并使 :key 参数可选.这是正确的方法吗:

I would like to remove the /l/ from my route (to make my url's shorter) and make the :key parameter optional. Would this be the correct way to do this:

app.get('/:key?', function(req, res, next){
  client.get(req.params.key, function(err, reply){
    if(client.get(reply)){
      res.redirect(reply);
    }
    else{
      next();
    }
  });
});

app.get('/', function(req, res){
  res.render('index, {
    link: null
  });
});

不确定我是否需要指定我的 / 路线是要下一个"的路线.但由于我唯一的其他路线是我更新后的 / 路线，我想它会正常工作.

Not sure if I need to specify that my / route is the one to be "nexted" to. But since my only other route would be my updated post / route, I would imagine it would work fine.

推荐答案

这取决于 client.get 在传递 undefined 作为其第一个参数时所做的工作.

That would work depending on what client.get does when passed undefined as its first parameter.

这样的东西会更安全:

app.get('/:key?', function(req, res, next) {
    var key = req.params.key;
    if (!key) {
        next();
        return;
    }
    client.get(key, function(err, reply) {
        if(client.get(reply)) {
            res.redirect(reply);
        }
        else {
            res.render('index', {
                link: null
            });
        }
    });
});

在回调中调用 next() 没有问题.

There's no problem in calling next() inside the callback.

根据this，处理程序按添加顺序调用, 所以只要你的下一条路由是 app.get('/', ...) 如果没有键就会被调用.

According to this, handlers are invoked in the order that they are added, so as long as your next route is app.get('/', ...) it will be called if there is no key.

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