Mongoose 不将数据保存到 MongoDB

下面是我试图保存到 MongoDB 的对象文字。它是在 app.js 文件中定义的，该文件是一个 Express 服务器。由于该对象是在服务器内硬编码的，因此我的假设是每次运行服务器时都会将一个新副本保存到数据库中，或者至少将文档保存一次，并在检测到该对象时覆盖或保持不变。新文档与上次服务器运行时保存的文档相同。令我惊讶的是，MongoDB 中不仅没有创建任何副本，而且该文档根本没有保存。但是，“新闻”集合已创建，已使用 mongo shell“显示集合”进行验证。另外，我在回调函数中没有收到任何错误。我还在我的 Express '/news' 路线中尝试了 Model.create(doc, fn) ，但这也不起作用（每次客户端调用 '/news' 路线时都应该保存文档，但它不是）。我缺少什么？
请阅读我标有“

var express = require('express')
  , routes = require('./routes')
  , user = require('./routes/user')
  , http = require('http')
  , path = require('path')
  , fs = require('fs');

// Defining connection to the database:
var mongoose = require('mongoose').
    connect("mongodb://localhost:27017/my-test-db"),
    db = mongoose.connection;
var Schema = mongoose.Schema;
var ObjectID = Schema.ObjectId;
// Setting up the debug flag:
mongoose.set('debug, true');
// Logging connection:
db
  .on('error', console.error.bind(console, 'DB connection error.'))
  .once('open', console.log.bind(console, 'DB Connection established.'));

// Defining MongoDB schemas:
var usr = new Schema({
    first: String,
    last: String
});
var newsSchema = new Schema({
    headline: String,
    bd: String,
    imgURI: String,
    imgThumbURI: String,
    imgCaption: String,
    addedOn: Date,
    addedBy: {
        type: ObjectID,
        ref: 'usr'
    }
// On user action 'save' populate the addedOn and addedBy fields before the news article is actually saved to the DB:
newsSchema.pre('save', function(next){
    if( !this.addedOn ) this.addedOn = new Date();
    if( !this.addedBy ) this.addedBy = {first: "admin", last: "admin"};
});
// Indexing important fields:
usr.index({last: 1});
newsSchema.index({headline: 1});
//Adding the News model:
var News = mongoose.model('news', newsSchema);

var nws1 = new News({
    headline: "Test news Headline",
    bd: "Test news body. Test news body. Test news body. Test news body. Test news body. ",
    imgURI: encodeURI("images/news/img.jpg"),
    imgThumbURI: encodeURI("images/news/thumbs/img.jpg"),
    imgCaption: "Test news image caption.",
    addedOn: new Date(),
    addedBy: {first: "Admin", last: "Admin"}
});
nws1.save(function(err, news){
        if(err) return console.error("Error while saving data to MongoDB: " + err); // <- this gets executed when there's an error
        console.error(news); // <- this never gets logged, even if there's no error.
    });

var app = express();

// all environments
app.set('port', process.env.PORT || 3000);
app.set('views', path.resolve(__dirname + '/public'));
app.set('view engine', 'html')
    .engine('html', function(path, options, fn){
        if('finction' == typeof options){
            fn = options, options = {};
        }
        fs.readFile(path, 'utf8', fn);
    });
app.use(express.favicon());
app.use(express.logger('dev'));
app.use(express.bodyParser());
app.use(express.methodOverride());
app.use(express.session());

app.use(express.static(path.join(__dirname, 'public')));
http.createServer(app).listen(app.get('port'), function(){
console.log('Express server listening on port ' + app.get('port'));
});

感谢您的时间
此致
Jared

看起来问题出在您的新闻架构的保存中间件中。

newsSchema.pre('save', function(next){
    if( !this.addedOn ) this.addedOn = new Date();
    if( !this.addedBy ) this.addedBy = {first: "admin", last: "admin"};
});

您的函数会收到一个“下一个”回调，您必须执行该回调以让猫鼬知道您已完成并准备好保存文档。由于您没有调用它，因此它可以解释为什么您没有保存任何内容，也没有错误。

尝试像这样调用 next ：

newsSchema.pre('save', function(next){
    if( !this.addedOn ) this.addedOn = new Date();
    if( !this.addedBy ) this.addedBy = {first: "admin", last: "admin"};
    next();
});