Node.JS single socket, multiple events (uploads)

Question

I'm developing an upload tracker (progress bar, etc).

So for my front-end I use jQuery File upload. Back-end upload is done using separate workers and there I use Redis pub/sub. So to connect front and back-ends I use Node.JS (socket.io).

jQuery file upload has a "done" callback function that denotes reaching our file to the server.

This works absolutely fine for a single file.

Problem arises when I try upload 2+ files simultaneously. "done" callback function is getting attached to socket listeners 2+ times (correct me if I'm wrong) and as an output I get something like this:

579 " - progress: " 8.333333333333334
580 " - progress: " 8.333333333333334 
579 " - progress: " 16.666666666666668 
580 " - progress: " 16.666666666666668 
579 " - progress: " 25 
580 " - progress: " 25
....
579 " -> upload is finished!" 
580 " -> upload is finished!"

That was an example of uploading 2 files. Which doesn't make any sense at all, because they can only be processed one after another.

So it should look like this:

579 " - progress: " 8.333333333333334
579 " - progress: " 16.666666666666668 
579 " - progress: " 25
....

579 " -> upload is finished!"
580 " - progress: " 8.333333333333334
580 " - progress: " 16.666666666666668
....
580 " -> upload is finished!"

Node.js server-side works totally fine. This is a log from it:

RECEIVED  progress  FROM  upload-579
RECEIVED  progress  FROM  upload-579
RECEIVED  progress  FROM  upload-579
RECEIVED  progress  FROM  upload-579
RECEIVED  progress  FROM  upload-579
RECEIVED  progress  FROM  upload-579
RECEIVED  progress  FROM  upload-579
RECEIVED  progress  FROM  upload-579
RECEIVED  progress  FROM  upload-579
RECEIVED  progress  FROM  upload-579
RECEIVED  progress  FROM  upload-579
RECEIVED  done  FROM  upload-579
RECEIVED  progress  FROM  upload-580
RECEIVED  progress  FROM  upload-580
RECEIVED  progress  FROM  upload-580
RECEIVED  progress  FROM  upload-580
RECEIVED  progress  FROM  upload-580
RECEIVED  progress  FROM  upload-580
RECEIVED  progress  FROM  upload-580
RECEIVED  progress  FROM  upload-580
RECEIVED  progress  FROM  upload-580
RECEIVED  progress  FROM  upload-580
RECEIVED  progress  FROM  upload-580
RECEIVED  done  FROM  upload-580

It received messages from Redis channel and emits appropriate messages to the client side. I think problem lies somewhere on the client side, but I cannot figure out how to modify the code there to get what I want. Can something be done to separate them from each other?

P.S

Why do you assume that the uploads can't happen concurrently? — Tom Erik Støwer
– Tom Erik Støwer, Commented Sep 19, 2014 at 7:03
There is only one worker that processes the upload. So it is absolutely NOT possible. Also, see the log I provided. — Dmitri
– Dmitri, Commented Sep 19, 2014 at 7:04
One Node worker or one Redis worker? Can you also show the Node.js code please? — Tom Erik Støwer
– Tom Erik Støwer, Commented Sep 19, 2014 at 7:12

Tom Erik Støwer · Accepted Answer · 2014-09-19 08:09:47Z

1

The socket event callback on the client-side will fire for any emit messages from Node.js. That's why you are seeing duplicate log messages. Either send additional data in the socket message, or attach unique events.

answered Sep 19, 2014 at 8:09

Tom Erik Støwer

1,40910 silver badges19 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Node.JS single socket, multiple events (uploads)

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related