I am trying to figure out how I can post an image directly to GridFS without storing it anywhere on the server as a temporary file first.

I am using Postman (chrome ext.) to post a file, and I manage to store this post as a file using:

req.pipe(fs.createWriteStream('./test.png'));

I am also able to store directly to GridFS from a readStream when the readStream is created from a file on the server. (see code)

I have the following files, saveFromReq.js which listens for the POST and basically just passes this on to the savePic.js.

saveFromReq.js:

var express = require('express');

var app = express();

var savePic = require('./savePic');

var fs = require('fs');

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

var pic = './square.png';

var picID;







//When the following



 //var pic = fs.createReadStream('./square.png', {autoClose: true});



//is not commented out, and 'req' is replaced with 'pic' in the savePic function,

//the file square.png is stored correctly to GridFS



app.post('/picture', function(req, res){



    savePic(req, function(id){});

    res.writeHead(200, {'Content-Type': 'text' });

    res.end(Sucsess!n);



});



app.listen(process.env.PORT || 3413);

savePic.js:

var savePic = function(req, callback){





var Db = require('mongodb').Db,

    MongoClient = require('mongodb').MongoClient,

    Server = require('mongodb').Server,

    ReplSetServers = require('mongodb').ReplSetServers,

    ObjectID = require('mongodb').ObjectID,

    Binary = require('mongodb').Binary,

    GridStore = require('mongodb').GridStore,

    Grid = require('mongodb').Grid,

    Code = require('mongodb').Code,

    BSON = require('mongodb').pure().BSON,

    assert = require('assert');

    fs = require('fs');



    //When the following 



      //req.pipe(fs.createWriteStream('./test.png'));



    //is not commented out, the correct image is stored to test.png, and 

    //the sequence after req.on(data... starts

    //(That sequence does not start at all when this is commented out..)



var fileId = new ObjectID();

var db = new Db('testDB', new Server('localhost', 27017));

// Establish connection to db

db.open(function(err, db) {





  var gridStore = new GridStore(db, 'test', 'w');



  //open 

  gridStore.open(function(err, gridStore) {

    console.log(opened);





    req.on(data, function (data) {

        console.log(data recieved);

            gridStore.write(data, function (err, gridStore) {

                if (err) {

                    console.log(error writing file);

                }

            });

        });

     req.on(end, function () {

            gridStore.close(function (err, gridStore) {

                if (!err) {

                    console.log(The file has been stored to database.);

                    db.close();

                }

            });

        });

           req.pipe(gridStore);





      });









});

callback(fileId);

};

module.exports = savePic;

Any help would be greatly appreciated!