Example code to use GridFS using mongoskin to upload file from form - mongoskin

Question

I am using mongoskin to connect mongodb in my project. Now I have requirement to use GridFs to upload images, audio etc. I have one HTML form to upload these files.
I tried to find out example code to upload file using mongoskin however could't find any good one.
Please help.

Answer 1

After spending many hours; I am able to use mongoskin to upload file to Gridfs. Not sure if this is perfect code however sharing it here because I couldn't find any single working code on searching Google :-)
https://github.com/dilipkumar2k6/gridfs-mongoskin
var DBModule = require('./DBModule.js');
var Grid = require('gridfs-stream');
var mongoskin = require('mongoskin');
//Upload file to server and also update the database
exports.uploadContent = function (req, res) {
console.log('Calling uploadFile inside FileUploadService');
req.pipe(req.busboy);
req.busboy.on('file', function (fieldname, file, filename, encoding, mimetype) {
console.log('uploadFile after busboy fieldname: ' + fieldname + ", file : " + file + ", filename : " + filename);
// make sure the db instance is open before passing into `Grid`
var gfs = Grid(DBModule.db, mongoskin);
//Get metadata var host = req.headers['host'];
var metadata = {contentType: mimetype};
var writestream = gfs.createWriteStream({filename: filename, metadata: metadata});
file.pipe(writestream);
writestream.on('close', function (file) {
// return URL to acces the uploaded content
var path = "contents/" + file._id;
res.json({"path": path});
});
writestream.on('error', function (err) {
log.error({err: err}, 'Failed to upload file to database');
res.status(constants.HTTP_CODE_INTERNAL_SERVER_ERROR);
res.json({error: err});
});
});
};
//view file from database
exports.previewContent = function (req, res) {
var contentId = new DBModule.BSON.ObjectID(req.params.contentid);
console.log('Calling previewFile inside FileUploadService for content id ' + contentId);
var gs = DBModule.db.gridStore(contentId, 'r');
gs.read(function (err, data) {
if (!err) {
//res.setHeader('Content-Type', metadata.contentType);
res.end(data);
} else {
log.error({err: err}, 'Failed to read the content for id ' + contentId);
res.status(constants.HTTP_CODE_INTERNAL_SERVER_ERROR);
res.json({error: err});
}
});
};

Answer 2

Try this to store the data using gridfs (by default uses mongoskin). It worked for me.
var ObjectID = require('mongodb').ObjectID,
GridStore = require('mongodb').GridStore;
exports.saveMedia = function(db, media, next) {
console.log(media)
db.open(function (err, db) {
// Create a file and open it
var gridStore = new GridStore(db, new ObjectID(), "w");
gridStore.open(function (err, gridStore) {
// Write some content to the file
gridStore.write(new Buffer(media), function (err, gridStore) {
// Flush the file to db
gridStore.close(function (err, fileData)
//returns filename
next(null, fileData)
});
});
});
});
}