abortConnection may throw EPIPE exception

[mingc00]

Note: for support questions, please use one of these channels: stackoverflow or slack

You want to:

• report a bug
• request a feature

Current behaviour

Application terminated by uncaught exception.

events.js:187
throw er; // Unhandled 'error' event
^

Error: write EPIPE
at afterWriteDispatched (internal/stream_base_commons.js:150:25)
at writeGeneric (internal/stream_base_commons.js:141:3)
at Socket._writeGeneric (net.js:771:11)
at Socket._write (net.js:783:8)
at doWrite (_stream_writable.js:431:12)
at writeOrBuffer (_stream_writable.js:415:5)
at Socket.Writable.write (_stream_writable.js:305:11)
at abortConnection (/volume1/@appstore/Spreadsheet/server/node_modules/engine.io/lib/server.js:506:12)
at /volume1/@appstore/Spreadsheet/server/node_modules/engine.io/lib/server.js:353:7
at Server.verify (/volume1/@appstore/Spreadsheet/server/node_modules/engine.io/lib/server.js:158:14)
Emitted 'error' event on Socket instance at:
at errorOrDestroy (internal/streams/destroy.js:108:12)
at onwriteError (_stream_writable.js:446:5)
at onwrite (_stream_writable.js:473:5)
at internal/streams/destroy.js:50:7
at Socket._destroy (net.js:664:5)
at Socket.destroy (internal/streams/destroy.js:38:8)
at afterWriteDispatched (internal/stream_base_commons.js:150:17)
at writeGeneric (internal/stream_base_commons.js:141:3)
at Socket._writeGeneric (net.js:771:11)
at Socket._write (net.js:783:8) {
  errno: 'EPIPE',
  code: 'EPIPE',
  syscall: 'write'
}

Steps to reproduce (if the current behaviour is a bug)

1. make Server be busy.

io.use(function(socket, next) {
  const time = Date.now() + 60000); // 1min
  while (Date.now() < time) {} // busy task
  next();
});

2. Client try to connect the socket.io server.
3. Close browser tab. ( abortConnection)
4. server may got EPIPE error.

Expected behaviour

Error should be ignore.

Setup

• OS: Node.js v12.14.1
• browser: Chrome
• engine.io version: 3.4.0

Other information (e.g. stacktraces, related issues, suggestions how to fix)

Add error handler before socket.write, otherwise EventEmitter will throw exception.

socket.once('error', function() { /* ignore */ });
socket.write(...);