快速404号公路

Question

我的node.js特快线路出问题了。我对它很陌生，我看不出我的错误。当请求localhost:2700/api/subs时，我总是收到404错误，但我认为我的路径是正确的，不是吗？有人看到错误了吗？

错误消息的开头：

错误:未在Layer.handle request的*/app.js:45:13处找到

这里是app.js

var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');

const mongoose = require('mongoose');

// establish connection to the Database
mongoose.connect('mongodb://localhost/test', {
  useMongoClient: true
});

mongoose.connection.once('open', function() {
  console.log('Connection to Database has been established..');
}).on('error', function(error){
  console.log(error);
});


var index = require('./routes/index');
var users = require('./routes/users');
Subscriber = require('./routes/subscriber.js');

var app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');

// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

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

// catch 404 and forward to error handler
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});

// error handler
app.use(function(err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render('error');
});

app.get('/api/subs', function(req, res){
    Subscriber.getSubscribers(function(err, subscribers){
        if(err){
            throw err;
        }
        res.json(subscribers);
    });
});

// ... here is a function which creates the database objects and saves         
//       them. took it out for better overview....

app.listen(2700, function(){
  console.log("Listening on Port 2700")
});

module.exports = app;

以及子目录中的subscriber.js ./：

const mongoose = require('mongoose');

var subscriberSchema = mongoose.Schema({
    //seqnr shall go here. dunno how to declare integer x)
    nr: Number,
    name: String,
    email: String,
    uLink: String,
    anwalt: String
});

var Subscriber = module.exports = mongoose.model('Subscriber', subscriberSchema);

//get Subscriber
module.exports.getSubscribers = function(callback, limit){
    Subscriber.find(callback).limit(limit);
};

index.js

var express = require('express');
var router = express.Router();

/* GET home page. */ 
router.get('/', function(req, res, next) {
  res.render('index', { title: 'Express' });
});

module.exports = router;

Answer 1

您需要将您的404 app.use放在所有其他用途之后，否则它将忽略它之后的api/subs。

此外，此位将永远不会运行，因为它还会在总是抛出错误的api.use之后运行：

// error handler
app.use(function(err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render('error');
});

此外，你真的不应该抛错404。它应该告诉最终用户页面不存在，但它不应该破坏您的脚本。

另外，我同意另一个答案，即你应该将这些代码块移动到单独的路由器文件中，但这更多的是为了良好的实践和结构，而不是针对这个特定的错误。

Answer 2

尝试将其放在单独的文件中，并将其包括在404处理程序之前与其他路由一起执行的位置。

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

所以..。做一个subs.js路线

var express = require('express');
var router = express.Router();
Subscriber = require('./routes/subscriber.js');

router.get('/', function(req, res){
    Subscriber.getSubscribers(function(err, subscribers){
        if(err){
            throw err;
        }
        res.json(subscribers);
    });
});

module.exports = router;

然后将其包含在您的app.js中

var subs= require('./routes/subs');
...
api.use('/api/subs', subs);
...
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});