Node.js: How to read a stream into a buffer?

Question

I wrote a pretty simple function that downloads an image from a given URL, resize it and upload to S3 (using \'gm\' and \'knox\'), I have no idea if I\'m doing the reading o

Answer 1

I suggest loganfsmyths method, using an array to hold the data.

var bufs = [];
stdout.on('data', function(d){ bufs.push(d); });
stdout.on('end', function(){
  var buf = Buffer.concat(bufs);
}

IN my current working example, i am working with GRIDfs and npm's Jimp.

   var bucket = new GridFSBucket(getDBReference(), { bucketName: 'images' } );
    var dwnldStream = bucket.openDownloadStream(info[0]._id);// original size
  dwnldStream.on('data', function(chunk) {
       data.push(chunk);
    });
  dwnldStream.on('end', function() {
    var buff =Buffer.concat(data);
    console.log("buffer: ", buff);
       jimp.read(buff)
.then(image => {
         console.log("read the image!");
         IMAGE_SIZES.forEach( (size)=>{
         resize(image,size);
         });
});

I did some other research

with a string method but that did not work, per haps because i was reading from an image file, but the array method did work.

const DISCLAIMER = "DONT DO THIS";
var data = "";
stdout.on('data', function(d){ 
           bufs+=d; 
         });
stdout.on('end', function(){
          var buf = Buffer.from(bufs);
          //// do work with the buffer here

          });

When i did the string method i got this error from npm jimp

buffer:  
{ Error: Could not find MIME for Buffer 

basically i think the type coersion from binary to string didnt work so well.