How to get all count of mongoose model?

Question

The reason your code doesn't work is because the count function is asynchronous, it doesn't synchronously return a value.

Here's an example of usage:

userModel.count({}, function( err, count){
    console.log( "Number of users:", count );
})

The code below works. Note the use of countDocuments.

 var mongoose = require('mongoose');
 var db = mongoose.connect('mongodb://localhost/myApp');
 var userSchema = new mongoose.Schema({name:String,password:String});
 var userModel =db.model('userlists',userSchema);
 var anand = new userModel({ name: 'anand', password: 'abcd'});
 anand.save(function (err, docs) {
   if (err) {
       console.log('Error');
   } else {
       userModel.countDocuments({name: 'anand'}, function(err, c) {
           console.log('Count is ' + c);
      });
   }
 }); 

You should give an object as argument

userModel.countDocuments({name: "sam"});

or

userModel.countDocuments({name: "sam"}).exec(); //if you are using promise

or

userModel.countDocuments({}); // if you want to get all counts irrespective of the fields

For the older versions of mongoose, use

userModel.count({name: "sam"});

The collection.count is deprecated, and will be removed in a future version. Use collection.countDocuments or collection.estimatedDocumentCount instead.

userModel.countDocuments(query).exec((err, count) => {
    if (err) {
        res.send(err);
        return;
    }

    res.json({ count: count });
});

Background for the solution

As stated in the mongoose documentation and in the answer by Benjamin, the method Model.count() is deprecated. Instead of using count(), the alternatives are the following:

Model.countDocuments(filterObject, callback)

Counts how many documents match the filter in a collection. Passing an empty object {} as filter executes a full collection scan. If the collection is large, the following method might be used.

Model.estimatedDocumentCount()

This model method estimates the number of documents in the MongoDB collection. This method is faster than the previous countDocuments(), because it uses collection metadata instead of going through the entire collection. However, as the method name suggests, and depending on db configuration, the result is an estimate as the metadata might not reflect the actual count of documents in a collection at the method execution moment.

Both methods return a mongoose query object, which can be executed in one of the following two ways. Use .exec() if you want to execute a query at a later time.

The solution

Option 1: Pass a callback function

For example, count all documents in a collection using .countDocuments():

someModel.countDocuments({}, function(err, docCount) {
    if (err) { return handleError(err) } //handle possible errors
    console.log(docCount)
    //and do some other fancy stuff
})

Or, count all documents in a collection having a certain name using .countDocuments():

someModel.countDocuments({ name: 'Snow' }, function(err, docCount) {
    //see other example
}

Option 2: Use .then()

A mongoose query has .then() so it’s “thenable”. This is for a convenience and query itself is not a promise.

For example, count all documents in a collection using .estimatedDocumentCount():

someModel
    .estimatedDocumentCount()
    .then(docCount => {
        console.log(docCount)
        //and do one super neat trick
    })
    .catch(err => {
        //handle possible errors
    })

Option 3: Use async/await

When using async/await approach, the recommended way is to use it with .exec() as it provides better stack traces.

const docCount = await someModel.countDocuments({}).exec();

Learning by stackoverflowing,

Using mongoose.js you can count documents,

• count all

const count = await Schema.countDocuments();

• count specific

const count = await Schema.countDocuments({ key: value });