node.js gridform + express

I'm trying to stream file uploads directly to Mongo. It seems like gridform (https://github.com/aheckmann/gridform) is a great solution for this.

I am already using the express framework and love what it's doing so want to keep using it, however the usage examples for gridform seem to be based on a native http server without express.

I found that the express.bodyParser() conflicts with gridform, so instead of:

app.use(express.bodyParser()); I'm using app.use(express.json()); app.use(express.urlencoded());

That part that's confusing me though is how I now use gridform within my route. app.post('/data/AddPropertyImage', db.addPropertyImage);

exports.addPropertyImage = function(req, res){ ??? }

Try as I might I can't seem to get a valid instance from var form = gridform(); this assertion keeps failing. assert(form instanceof formidable.IncomingForm);

This is the full code seg.

exports.addPropertyImage = function(req, res){

    var mongo = require('mongodb')
    var formidable = require('formidable');
    var assert = require('assert');

    var Db = require('mongodb').Db;
    var Server = require('mongodb').Server;
    var MongoDb = new Db('test', new Server('localhost', 27017), {w: 1});

    MongoDb.open(function(err, db) {
        var gridform = require('gridform');
        gridform.db = db;
        gridform.mongo = mongo;
        var form = gridform();

        // returns a custom IncomingForm
        assert(form instanceof formidable.IncomingForm);
        // this returns AssertionError: false == true 
    });

    res.send('test');
};

Edit...

As stated below I needed to use the specific version of formidable var formidable = require('gridform/node_modules/formidable');

The assertion now passes but the form.parse() doesn't seem to ever trigger. So the console.log('start parse'); line below is never hit.

    console.log('start');
    var mongo = require('mongodb')
    //var formidable = require('formidable');
    var formidable = require('gridform/node_modules/formidable');
    var gridfsStream = require('gridform/node_modules/gridfs-stream');
    console.log(gridfsStream);
    var assert = require('assert');

    var Db = require('mongodb').Db;
    var Server = require('mongodb').Server;
    var MongoDb = new Db('test', new Server('localhost', 27017), {w: 1});

    console.log('mongo open');
    MongoDb.open(function(err, db) {
        var gridform = require('gridform');
        gridform.db = db;
        gridform.mongo = mongo;
        var form = gridform();

        // returns a custom IncomingForm
        assert(form instanceof formidable.IncomingForm);
        // this returns AssertionError: false == true
        console.log('assert passed');

        // optionally store per-file metadata
        form.on('fileBegin', function (name, file) {
            console.log('mmmeta');
            file.metadata = 'so meta'
        })

        // parse normally
        form.parse(req, function (err, fields, files) {
            console.log('start parse');
            // use files and fields as you do today
            var file = files.inpFile1;
            console.log(file);
            file.name // the uploaded file name
            file.type // file type per [mime](https://github.com/bentomas/node-mime)
            file.size // uploaded file size (file length in GridFS) named "size" for compatibility
            file.path // same as file.name. included for compatibility
            file.lastModified // included for compatibility

            // files contain additional gridfs info
            file.root // the root of the files collection used in MongoDB ('fs' here means the full collection in mongo is named 'fs.files')
            file.id   // the ObjectId for this file

        });
    });

    res.send('test');