Cannot receive Buffer in NodeJS server/client

[jacargentina]

You want to:

• report a bug
• request a feature

Current behaviour

Emitting a Buffer is not working, the client is not receiving anything.

Steps to reproduce

• git clone https://github.com/jacargentina/socket-test
• cd socket-test
• npm install
• npm run test-fail

Also can do npm run test-pass which is exactly the same but emitting a string, which simply works!

Expected behaviour

Should just work

Setup

• OS: macOS/Linux
• socket.io version: 2.1.1

[jacargentina]

@darrachequesne could u look at this please?

[darrachequesne]

@jacargentina thanks for providing a way to reproduce, that really helps 👍

That looks reaaaaaally weird, I'm not able to reproduce within the fiddle: https://github.com/socketio/socket.io-fiddle/tree/issues-3316

// server-side
  socket:test starting server +0ms
  socket:test connection +4s /hub#VduhqmBscd9Z3sMsAAAA
  socket:test data response +6ms <Buffer 68 69 21>
// client-side
  socket:test starting client +0ms
  socket:test connected +73ms
  socket:test data +0ms <Buffer 68 65 6c 6c 6f 20 79 6f 75 21>

Hmm... could it be related to jest?

Edit: possibly related to jestjs/jest#3186

[jacargentina]

@darrachequesne you're right with jest, replacing with mocha just works! At least i can go on with mocha, while jest team fixes this.

[efkan]

@jacargentina , @darrachequesne

I've spent three days to diagnosis this issue. Anyway..

Yes, Mocha testing works seamlessly and I also use Mocha when testing socket.io related code.

I've just realized that if server allowUpgrades option is set as false then Jest testing can be passed!

As a workaround allowUpgrades option can be set as false for testing like the following:

if (process.env.NODE_ENV === 'test') {
  io = require('socket.io')(server, {  allowUpgrades : false }); 
} else {
  // current socket constuction code
}

If the issue is the same as mine it must works.

Edit
Actually giving {upgrade: false} option to socket.io-client is more sense.

const socket = require('socket.io-client')(serverUrl, {upgrade: false});

[darrachequesne]

Closed due to inactivity, please reopen if needed.