Combine Jimp-module with Amazon AWS S3 in NodeJS

Question

The following I want to achieve:

1. Upload a picture to my backoffice
2. Resize this picture to reduce image-size.
3. Upload this picture to Amazon AWS S3.

I couldn't figure out how to directly store the picture to Amazon AWS S3 and therefore I upload it first to my backoffice.

My code:

router.post('/fileupload', function(req, res){

  // Prepare data
  var file = req.files.upfile;
  var uploadpath = 'profilepicture/' + req.session.user + '.jpg';
  var AWS = require('aws-sdk');
  var fs = require('fs');
  AWS.config.update({
    accessKeyId: **,
    secretAccessKey: **
  });

  // Upload file
  file.mv(uploadpath,function(err){
    if (err) throw err;

    // Read in the file, convert it to base64, store to S3
     Jimp.read(uploadpath, function (err, data) {
       if (err) throw err;

       // Reduce size
       data.resize(400, Jimp.AUTO).quality(100).write(uploadpath);

       var s3 = new AWS.S3();
       var stream = fs.createReadStream(uploadpath);

       s3.putObject({
           Bucket: bucketAmazon,
           Key: req.session.user + '.jpg',
           ContentType: 'image/jpg',
           Body: stream,
           ContentEncoding: 'base64',
           ACL: 'public-read',
           Metadata: {
             'Content-Type': 'image/jpeg'
           }
         }, function (resp) {
           console.log(arguments);
           console.log('Successfully uploaded package.');
           return res.render('settings', {
             user: req.session.user,
             logged: true,
             wrongPicture: false
           });
       });
    });
  });
});

However, when I run this code: the file is uploaded to my backoffice and cropped correctly but in Amazon AWS S3 it shows that the size is '0 B'.

If I remove the line data.resize(400, Jimp.AUTO).quality(100).write(uploadpath) , then the file is uploaded correctly to Amazon AWS S3, but ofcourse the picture is not reduced.

Answer 1

You can use the write callback to guarantee that the file is written before the upload starts.

...
data.resize(400, Jimp.AUTO).quality(100).write(uploadpath, () => {
    // upload to s3 code here
});