Node.js stream upload directly to Google Cloud Storage - node.js

Question

I have a Node.js app running on a Google Compute VM instance that receives file uploads directly from POST requests (not via the browser) and streams the incoming data to Google Cloud Storage (GCS).
I'm using Restify b/c I don't need the extra functionality of Express and because it makes it easy to stream the incoming data.
I create a random filename for the file, take the incoming req and toss it to a neat little Node wrapper for GCS (found here: https://github.com/bsphere/node-gcs) which makes a PUT request to GCS. The documentation for GCS using PUT can be found here: https://developers.google.com/storage/docs/reference-methods#putobject ... it says Content-Length is not necessary if using chunked transfer encoding.
Good news: the file is being created inside the appropriate GCS storage "bucket"!
Bad News:
I haven't figured out how to get the incoming file's extension from Restify (notice I'm manually setting '.jpg' and the content-type manually).
The file is experiencing slight corruption (almost certainly do to something I'm doing wrong with the PUT request). If I download the POSTed file from Google, OSX tells me its damaged ... BUT, if I use PhotoShop, it opens and looks just fine.
Update / Solution
As pointed out by vkurchatkin, I needed to parse the request object instead of just piping the whole thing to GCS. After trying out the lighter busboy module, I decided it was just a lot easier to use multiparty. For dynamically setting the Content-Type, I simply used Mimer (https://github.com/heldr/mimer), referencing the file extension of the incoming file. It's important to note that since we're piping the part object, the part.headers must be cleared out. Otherwise, unintended info, specifically content-type, will be passed along and can/will conflict with the content-type we're trying to set explicitly.
Here's the applicable, modified code:
var restify = require('restify'),
server = restify.createServer(),
GAPI = require('node-gcs').gapitoken,
GCS = require('node-gcs'),
multiparty = require('multiparty'),
Mimer = require('mimer');
server.post('/upload', function(req, res) {
var form = new multiparty.Form();
form.on('part', function(part){
var fileType = '.' + part.filename.split('.').pop().toLowerCase();
var fileName = Math.random().toString(36).slice(2) + fileType;
// clear out the part's headers to prevent conflicting data being passed to GCS
part.headers = null;
var gapi = new GAPI({
iss: '-- your -- #developer.gserviceaccount.com',
scope: 'https://www.googleapis.com/auth/devstorage.full_control',
keyFile: './key.pem'
},
function(err) {
if (err) { console.log('google cloud authorization error: ' + err); }
var headers = {
'Content-Type': Mimer(fileType),
'Transfer-Encoding': 'Chunked',
'x-goog-acl': 'public-read'
};
var gcs = new GCS(gapi);
gcs.putStream(part, myBucket, '/' + fileName, headers, function(gerr, gres){
console.log('file should be there!');
});
});
});
};

Answer 1

You can't use the raw req stream since it yields whole request body, which is multipart. You need to parse the request with something like multiparty give you a readable steam and all metadata you need.