mongodb 神秘错误 process.nextTick(function() { throw err; }) ^ Error at Object.<anonymous>

Question

在添加 mongoose 和几个 mongoose Schema 后尝试启动我的 MEAN 应用程序时，我遇到了一个奇怪的错误。

node_modules/mongoose/node_modules/mongodb/lib/server.js:228
        process.nextTick(function() { throw err; })
                                            ^
Error
    at Object.<anonymous> (/Projects/node/flapper-news/node_modules/mongoose/node_modules/mongodb/node_modules/mongodb-core/lib/error.js:42:24)
    at Module._compile (module.js:460:26)
    at Object.Module._extensions..js (module.js:478:10)
    at Module.load (module.js:355:32)
    at Function.Module._load (module.js:310:12)
    at Module.require (module.js:365:17)
    at require (module.js:384:17)
    at Object.<anonymous> (/Projects/node/flapper-news/node_modules/mongoose/node_modules/mongodb/node_modules/mongodb-core/index.js:2:17)
    at Module._compile (module.js:460:26)
    at Object.Module._extensions..js (module.js:478:10)

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');
var mongoose = require('mongoose');

require('./models/Posts');
require('./models/Comments');
mongoose.connect('mongodb://localhost/news');

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

var app = express();

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

// uncomment after placing your favicon in /public
//app.use(favicon(__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('/', routes);
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 handlers

// development error handler
// will print stacktrace
if (app.get('env') === 'development') {
  app.use(function(err, req, res, next) {
    res.status(err.status || 500);
    res.render('error', {
      message: err.message,
      error: err
    });
  });
}

// production error handler
// no stacktraces leaked to user
app.use(function(err, req, res, next) {
  res.status(err.status || 500);
  res.render('error', {
    message: err.message,
    error: {}
  });
});


module.exports = app;

路线

var express = require('express'),
    router = express.Router(),
    mongoose = require('mongoose'),
    Post = mongoose.model('Post'),
    Comment= mongoose.model('Comment');

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

router.get('/posts', function(req, res, next) {
    Post.find(function(err, posts){
        if(err){
            return next(err);
        }

        res.json(posts);
    });
});

router.post('/posts', function(req, res, next) {
    var post = new Post(req.body);

    post.save(function(err, post) {
        if (err) {
            return next(err);
        }
        res.json(post);
    });
});

module.exports = router;

模式

var mongoose = require('mongoose');

var PostSchema = new mongoose.Schema({
    title: String,
    link: String,
    upvotes: {type: Number, default: 0},
    comments: [{ type: mongoose.Schema.Types.ObjectId, ref: 'Comment' }]
});

mongoose.model('Post', PostSchema);

var CommentSchema = new mongoose.Schema({
    body: String,
    author: String,
    upvotes: {type: Number, default: 0},
    post: { type: mongoose.Schema.Types.ObjectId, ref: 'Post' }
});

mongoose.model('Comment', CommentSchema);

我之前在 app.js 中声明 app = express() 之后有架构和 mongoose 连接调用 ，但这引发了不同的错误。有人能看出我哪里出错了吗？

Answer 1

我没有为我的 MongoDB 安装创建 /data/db 目录。创建目录并将自己设置为所有者，现在一切正常。