插入Mongodb集合（新手）

Question

I'm new to nodejs and mongodb. I'm trying to insert newClass into the class collection. Everything seems to be working except this function. It gives a 500 error and doesn't save the class.

I checked the mongodb docs and it seemed correct. Can someone please point me in the right direction?

routes

Class.createNewClass(newClass, function(err){
    if (err){
        console.log(err);
        res.send(err);
    } else {
        console.log('Class saved.")
    }
})

model

module.exports.createNewClass = function(newClass, callback){
    Class.insert({newClass}, callback);
}

Answer 1

There's a syntax error in your createNewClass function, assuming the newClass variable is an object that contains all the key:value pairs you're saving to the new document, you should remove the curly braces:

module.exports.createNewClass = function(newClass, callback){
    Class.insert(newClass, callback);
}

That said, the code you posted for your routes doesn't look much like a route to me, so there could be other errors your transcription is not revealing.

Answer 2

I'm not really clear on the overall structure of your app, but here is a very simple Express app that can insert new classes to the database.

var express = require('express');
var bodyParser = require('body-parser');

var mongodb = require('mongodb');
var app = express();
app.use(bodyParser.json());

var MongoClient = require('mongodb').MongoClient;
var db;

// Initialize connection once
MongoClient.connect("mongodb://localhost:27017/school", function(err, database) {
  if(err) throw err;

  db = database;

  // Start the application after the database connection is ready
  app.listen(3000);
  console.log("Listening on port 3000");
});

app.post('/class', function(req,res) {
  var collection = db.collection('classes');
  var newClass = req.body;
  console.log(req.body);
  collection.insert(newClass);
  res.json(newClass);
});

Answer 3

In your model change it to:

module.exports.createNewClass = function(newClass, callback){
      Class.collection.insert(newClass, callback);
};

Check that "Class" should be schema model object.

  module.exports.createNewClass = function(newClass, callback){
      new Class(newClass).save(callback);
    };

It's the basic mongoose way. In mongoose we use "insert" to multiple documents but you can also use insert for single document.