handle EPIPE gracefully about axon HOT 10 CLOSED

+1 for this ticket. And I think it's about ECONNRESET too:

events.js:68
throw arguments[1]; // Unhandled 'error' event
^
Error: write ECONNRESET
at errnoException (net.js:769:11)
at Object.afterWrite (net.js:593:19)

from axon.

@visionmedia I am messing with this too, however it gets complicated. :-) Given that with EPIPE and ECONNRESET we did actually connect to the peer, but it broke mid-flight, meaning we did not fallback to enqueue(). Wondering if we should re-tweak a few things to have any sockets that need to buffer actually always enqueue messages and have them removed upon an "ack" message from the peer... Not all the different from keeping track of a "callback stack" with req/rep.

Anyhow, you can reproduce easily with larger messages that will be chunked, then close() the peer: gjohnson@233bc1c

from axon.

good point, hmMmM.. I'm seeing

    if (nbytes == -1 && (errno == ECONNRESET || errno == EPIPE ||
          errno == ETIMEDOUT))
        return -1;

in zmq's .write(), followed by the out_event():

    //  Handle problems with the connection.
    if (nbytes == -1) {
        error ();
        return;
    }

and

#if defined ZMQ_HAVE_OSX || defined ZMQ_HAVE_FREEBSD
    //  Make sure that SIGPIPE signal is not generated when writing to a
    //  connection that was already closed by the peer.
    int set = 1;
    int rc = setsockopt (s, SOL_SOCKET, SO_NOSIGPIPE, &set, sizeof (int));
    errno_assert (rc == 0);

in the constructor, seems like they just bail on errors as well

from axon.

I think it's easy to handle at least in pub/sub: just drop the message being sent like the socket had been already shut down prior to error.

from axon.

yeah agreed that's definitely the easy case

from axon.

That commit I referenced would do that, I can pull... it will just hide errors on the other sockets as a side-effect, for now at least.

from axon.

sounds good, we might have to mock some node internals to get a reproducible test case, that one just hung for me

from axon.

Here's a js that stably reproduces such errors, just uncomment corresponding line:

var net = require('net');
var server = net.createServer(function(c) {
  c.write('hello\r\n');
  c.pipe(c);
});
server.listen(8124, function() {});

var client = net.connect({port: 8124}, function() { //'connect' listener
  //server.close(); // reproduces ECONNRESET
  var msg = 'world';
  client.write(msg);
  //client.destroy(); // reproduces EPIPE
});

from axon.

@AlexeyKupershtokh awesome thanks I will try that out in a minute

from axon.

just ended up sneaking in some faux errors

from axon.