What type should I specify the image to be used using the waterline?

Question

Waterline in Sails is pretty cool, and this layer of abstraction is very useful. My question is: how to store images using the waterline? There is a type called binary. Should I use this type? Should I just transfer the image like any other data type? How to check the image, say, make sure that its format is one of several given parameters, such as png, jpeg, etc.

Answer 1

I would not recommend using a binary file to store images directly in your db. If your users want to upload images, it’s kind of a pain, and I don’t think that waterline supports streaming to the database. There is an alternative though!

Mongodb has a gridfs function that breaks large files into pieces and saves them for you.

The Sails file download library, skipper , has an adapter concept (such as a waterline) that allows you to connect an adapter to a download file. There the adapter is called skipper-gridfs , which does it for you! I used this and it is very easy to use. What are you doing:

Define the model sails, call it Image, it has the properties filename and filedescriptor

filedescriptor - , mongo . , ( ) gridfs filedescriptor. ( ) gridfs .

:

var adapter = require('skipper-gridfs');


 upload : function (req, res, next) {

    var params = req.params.all();

    var gf = _gridfs;

    //upload file to gridfs
    req.file('file').upload(
        {
            adapter:adapter,
            uri:constring
        },
        function (err,uploadedFiles){
            if (err) {return res.send(err);}

            var imagePromiseArray = [];
            //loop over the files uploaded to gridfs and store references to their IDs   in your Image model
            _.each(uploadedFiles,function(file){
                var imageParams = {
                    filename:file.filename,
                    fileDescriptor:file.fd
                };
                imagePromiseArray.push(Image.create(imageParams));

            });

            Promise
                .all(imagePromiseArray)
                .then(function(results){
                    res.status(200);
                    return res.send(results);
                })
                .catch(function(err){
                    res.status(500);
                    res.send(err);
                });

    });


},

:

var mime = require('mime');
download: function (req, res, next) {
    var params = req.params.all();

        Image
            .findOne(params.id)
            .then(function (image) {
                debugger;

                _gridfs.read(image.fileDescriptor, function (err, data) {

                    if (err) {
                        res.status(500);
                        res.json(err);
                    }
                    if (!data) {
                        res.status(404);
                        res.json({error: 'image not found'});
                    } else {
                        res.setHeader('Content-disposition', 'attachment; filename=' + image.filename);
                        var type = mime.lookup(image.filename);
                        res.setHeader('Content-type', type);
                        res.send(data);
                    }
                });

            })
            .catch(function (err) {
                res.json(err);
            });


},