gridfs-storage-engine

gridfs-storage-engine is a Multer Storage Engine implementation for Gridfs (MongoDB).

It allows you to stream files from your form or nodejs application into your mongodb directly.

How does it work

gridfs-storage-engine streams a file or group of files to mongodb using grind-stream.

Following the Multer Storage Engine pattern, to use this Storage engine you will need to initialize it with multer.

var storage = require('gridfs-storage-engine')();
var upload = multer({ storage: storage });

Then you could activate it for the end points that you choose

router.post('/api/v1/uploadFile/', upload.single('file'), function () { //what next } );
router.post('/api/v1/uploadFiles', upload.array('files'), function () { //what next });

Any key/value body elements a part from the file, will be added as the file metadata.

If there is no connection on initialization, the system will throw an exception.

You can catch the error and retry to reconnect using the function connectToMongoDB

Options

By default, gridfs-storage-engine will try to open a database connection with the following details

{
    database: 'test',
    hostname: '127.0.0.1',
    port: 27017,
    url: undefined
}

You can overwrite those by providing as parameters of the require.

var storage = require('gridfs-storage-engine')({
    database: 'yourDatabase'
});
var upload = multer({ storage: storage });

You can use the normal url parameter to connect to a mongoDB database like mongodb://localhost:27017/test. This is the prefered method.

If you need to submit files using nodejs check form-data.

Current limitations & future improvements

No tests provided. Adding test coverage will be a next release priority.

As per multer limitations, the only supported encoding is "multipart/form-data".

There isn't a check for duplicate files. If you insert a file that is already present in the datase, a new record will be created. This is a limitations of GridFS and can be addressed by removing the old file after an insert.

Further reading

Multer Storage Engine

GridFS