Stream file uploaded with Express.js through formidable and gm to eliminate double write

Question

I want to upload and resize an image in one go without writing to disk twice.

To upload the image I use: node-formidable: https://github.com/felixge/node-formidable

To resize the image I use: gm: http://aheckmann.github.com/gm/

When I run this code I get an error: 'This socket is closed'.

Error: spawn ENOENT at errnoException (child_process.js:988:11) at Process.ChildProcess._handle.onexit (child_process.js:779:34)

My code:

function uploadPhotos (req, res) {
  // parse a file upload
  var form = new formidable.IncomingForm();
  form.multiples = true;      // Allow multiple files with HTML5 multiple attribute.
  form.maxFields = 100;       // Maximum number of fields (no files).
  form.keepExtensions = true; // Include the extensions of the original files.
  form.uploadDir = ORIGINAL_IMAGES_DIR;

  form.onPart = function (part) {

    if (!part.filename) {
      // Let formidable handle all non-file parts.
      return this.handlePart(part);
    }

    gm(part)
    .resize(200, 200)
    .stream(function (err, stdout, stderr) {
      stdout.pipe(fs.createWriteStream(path.join(RESIZED_IMAGES_DIR, 'resized_' + part.filename)));
      stdout.on('end', function () {
        res.send(200);
      });
    });
  };

  form.parse(req);
}

I can't figure out what the problem is. A similar problem can be found here: Stream file uploaded with Express.js through gm to eliminate double write

Any suggestions?

Thanks!

Answer 1

I thought npm install would do the trick but it didn't install GraphicsMagick. Installing GraphicsMagick manually solved my problem.

Thanks to tuck: gm stream stdout pipe throwing unhandled error