Save binary file in MongoDB

mongo-binary.js

var mongoBinary = {

    save : function(url, collection, filename) {

        var fs = require('fs')
        var Binary = require('mongodb').Binary
        var MongoClient = require('mongodb').MongoClient
        var assert = require('assert')

        var doc = {
            name: filename,
            data: new Binary(fs.readFileSync(filename))
        }

        MongoClient.connect(url, function(err,db) {
            assert.equal(null,err,err)
            
            db.collection(collection).insert(doc, function(err,res) {
                assert.equal(null,err,err)
                console.log(res)
            })
        })
    },

    write : function(url, collection, filename, outname) {

        var outname = outname || filename

        var fs = require('fs')
        var Binary = require('mongodb').Binary
        var MongoClient = require('mongodb').MongoClient
        var assert = require('assert')

        var doc = {
            name: filename
        }

        MongoClient.connect(url, function(err,db) {
            assert.equal(null,err,err)
            
            db.collection(collection).find(doc).next(function(err,res) {
                assert.equal(null,err,err)
            
                fs.writeFile(outname, res.data.buffer, function(err) {
                    assert.equal(null,err,err)
                    console.log('File ' + outname + ' saved.')
                })
            })
        })
    }

}