如何在 Mongoose/Node.js 中同时保存多个文档?

目前,我使用 save 来添加单个文档。假设我有一个希望存储为单个对象的文档数组。有没有一种方法可以通过一个函数调用将它们全部添加,然后在调用完成后获得一个回调?我可以单独添加所有的文档,但是管理回调以确定什么时候完成所有工作将是有问题的。

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Mongoose doesn't have bulk inserts implemented yet (see issue #723).

Since you know the number of documents you're saving, you could write something like this:

var total = docArray.length
, result = []
;


function saveAll(){
var doc = docArray.pop();


doc.save(function(err, saved){
if (err) throw err;//handle error


result.push(saved[0]);


if (--total) saveAll();
else // all saved here
})
}


saveAll();

This, of course, is a stop-gap solution and I would recommend using some kind of flow-control library (I use q and it's awesome).

Here is another way without using additional libraries (no error checking included)

function saveAll( callback ){
var count = 0;
docs.forEach(function(doc){
doc.save(function(err){
count++;
if( count == docs.length ){
callback();
}
});
});
}

Mongoose does now support passing multiple document structures to Model.create. To quote their API example, it supports being passed either an array or a varargs list of objects with a callback at the end:

Candy.create({ type: 'jelly bean' }, { type: 'snickers' }, function (err, jellybean, snickers) {
if (err) // ...
});

Or

var array = [{ type: 'jelly bean' }, { type: 'snickers' }];
Candy.create(array, function (err, jellybean, snickers) {
if (err) // ...
});

Edit: As many have noted, this does not perform a true bulk insert - it simply hides the complexity of calling save multiple times yourself. There are answers and comments below explaining how to use the actual Mongo driver to achieve a bulk insert in the interest of performance.

Add a file called mongoHelper.js

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


MongoClient.saveAny = function(data, collection, callback)
{
if(data instanceof Array)
{
saveRecords(data,collection, callback);
}
else
{
saveRecord(data,collection, callback);
}
}


function saveRecord(data, collection, callback)
{
collection.save
(
data,
{w:1},
function(err, result)
{
if(err)
throw new Error(err);
callback(result);
}
);
}
function saveRecords(data, collection, callback)
{
save
(
data,
collection,
callback
);
}
function save(data, collection, callback)
{
collection.save
(
data.pop(),
{w:1},
function(err, result)
{
if(err)
{
throw new Error(err);
}
if(data.length > 0)
save(data, collection, callback);
else
callback(result);
}
);
}


module.exports = MongoClient;

Then in your code change you requires to

var MongoClient = require("./mongoHelper.js");

Then when it is time to save call (after you have connected and retrieved the collection)

MongoClient.saveAny(data, collection, function(){db.close();});

You can change the error handling to suit your needs, pass back the error in the callback etc.

Use async parallel and your code will look like this:

  async.parallel([obj1.save, obj2.save, obj3.save], callback);

Since the convention is the same in Mongoose as in async (err, callback) you don't need to wrap them in your own callbacks, just add your save calls in an array and you will get a callback when all is finished.

If you use mapLimit you can control how many documents you want to save in parallel. In this example we save 10 documents in parallell until all items are successfully saved.

async.mapLimit(myArray, 10, function(document, next){
document.save(next);
}, done);

I know this is an old question, but it worries me that there are no properly correct answers here. Most answers just talk about iterating through all the documents and saving each of them individually, which is a BAD idea if you have more than a few documents, and the process gets repeated for even one in many requests.

MongoDB specifically has a batchInsert() call for inserting multiple documents, and this should be used from the native mongodb driver. Mongoose is built on this driver, and it doesn't have support for batch inserts. It probably makes sense as it is supposed to be a Object document modelling tool for MongoDB.

Solution: Mongoose comes with the native MongoDB driver. You can use that driver by requiring it require('mongoose/node_modules/mongodb') (not too sure about this, but you can always install the mongodb npm again if it doesn't work, but I think it should) and then do a proper batchInsert

Bulk inserts in Mongoose can be done with .insert() unless you need to access middleware.

Model.collection.insert(docs, options, callback)

https://github.com/christkv/node-mongodb-native/blob/master/lib/mongodb/collection.js#L71-91

Newer versions of MongoDB support bulk operations:

var col = db.collection('people');
var batch = col.initializeUnorderedBulkOp();


batch.insert({name: "John"});
batch.insert({name: "Jane"});
batch.insert({name: "Jason"});
batch.insert({name: "Joanne"});


batch.execute(function(err, result) {
if (err) console.error(err);
console.log('Inserted ' + result.nInserted + ' row(s).');
}

You can use the promise returned by mongoose save, Promise in mongoose does not have all, but you can add the feature with this module.

Create a module that enhance mongoose promise with all.

var Promise = require("mongoose").Promise;


Promise.all = function(promises) {
var mainPromise = new Promise();
if (promises.length == 0) {
mainPromise.resolve(null, promises);
}


var pending = 0;
promises.forEach(function(p, i) {
pending++;
p.then(function(val) {
promises[i] = val;
if (--pending === 0) {
mainPromise.resolve(null, promises);
}
}, function(err) {
mainPromise.reject(err);
});
});


return mainPromise;
}


module.exports = Promise;

Then use it with mongoose:

var Promise = require('./promise')


...


var tasks = [];


for (var i=0; i < docs.length; i++) {
tasks.push(docs[i].save());
}


Promise.all(tasks)
.then(function(results) {
console.log(results);
}, function (err) {
console.log(err);
})

This is an old question, but it came up first for me in google results when searching "mongoose insert array of documents".

There are two options model.create() [mongoose] and model.collection.insert() [mongodb] which you can use. View a more thorough discussion here of the pros/cons of each option:

Mongoose (mongodb) batch insert?

Here is an example of using MongoDB's Model.collection.insert() directly in Mongoose. Please note that if you don't have so many documents, say less than 100 documents, you don't need to use MongoDB's bulk operation (see this).

MongoDB also supports bulk insert through passing an array of documents to the db.collection.insert() method.

var mongoose = require('mongoose');


var userSchema = mongoose.Schema({
email : { type: String, index: { unique: true } },
name  : String
});


var User = mongoose.model('User', userSchema);




function saveUsers(users) {
User.collection.insert(users, function callback(error, insertedDocs) {
// Here I use KrisKowal's Q (https://github.com/kriskowal/q) to return a promise,
// so that the caller of this function can act upon its success or failure
if (!error)
return Q.resolve(insertedDocs);
else
return Q.reject({ error: error });
});
}


var users = [{email: 'foo@bar.com', name: 'foo'}, {email: 'baz@bar.com', name: 'baz'}];
saveUsers(users).then(function() {
// handle success case here
})
.fail(function(error) {
// handle error case here
});

Mongoose 4.4 added a method called insertMany

Shortcut for validating an array of documents and inserting them into MongoDB if they're all valid. This function is faster than .create() because it only sends one operation to the server, rather than one for each document.

Quoting vkarpov15 from issue #723:

The tradeoffs are that insertMany() doesn't trigger pre-save hooks, but it should have better performance because it only makes 1 round-trip to the database rather than 1 for each document.

The method's signature is identical to create:

Model.insertMany([ ... ], (err, docs) => {
...
})

Or, with promises:

Model.insertMany([ ... ]).then((docs) => {
...
}).catch((err) => {
...
})

Use insertMany function to insert many documents. This sends only one operation to the server and Mongoose validates all the documents before hitting the mongo server. By default Mongoose inserts item in the order they exist in the array. If you are ok with not maintaining any order then set ordered:false.

Important - Error handling:

When ordered:true validation and error handling happens in a group means if one fails everything will fail.

When ordered:false validation and error handling happens individually and operation will be continued. Error will be reported back in an array of errors.