better network error messages

[tj]

I've brought this up before but I can't find the issue, or if/why it was denied, but anyway I think we could do a lot better with network related error reporting:

Error: connect ECONNREFUSED
    at errnoException (net.js:901:11)
    at Object.afterConnect [as oncomplete] (net.js:892:19)

isn't overly informative, it would be awesome if (when available) we tack on some information, host/port etc. It's easy to argue that when you receive the error you should be printing it or doing something with it in a way that makes the message more useful, but it certainly wouldn't hurt for cases where you just use a console.error(err.stack) etc

[tjfontaine]

That's a reasonable request, I would enthusiastically review such a PR

[trevnorris]

Don't have source in front of me, but do we make sure to always attach the
E* to error.code?

[tjfontaine]

The code is already supplied in the example, econnreset, but like we
do for child process of including command and args, for network errors
we could provide context like remote and local host and port

[tj]

rad! I'll try and send a patch over in the next few days when I have a chance

[bpytlik]

Since issue #7042 was closed as a dup of this one, please take a broad interpretation of this issue to also cover things like failed dns lookup. The lack of information is a broader problem than just net.js. It's just my 2 cents, but it might be worth having Socket.prototype.send (in dgram.js) handle a bunch of these issues. I don't know if your path to net.js also passes through that code, but in my case that seemed like the place that really had the useful information about what was being attempted.

[tj]

haven't had time for a patch yet but yeah this is a massive issue in production haha :D. Nothing worse than getting this in your logs, IMO this should be pretty high priority, it renders node pretty useless unless you manually go tag every single error in the system

  { message: 'write EPIPE',
    stack: 'Error: write EPIPE\n    at errnoException (net.js:770:11)\n    at Object.afterWrite (net.js:594:19)',
    code: 'EPIPE',
    errno: 'EPIPE',
    syscall: 'write',
    app: 'ingestion' }

EDIT:

something like:

{ message: '10.0.1.99:1234 - write EPIPE',
  host: '10.0.1.99',
  port: 1234
...

[rauchg]

+1 – we've gone extremely long with these uninformative errors. Definitely nice for 0.12

[Fishrock123]

👍

[jpillora]

👍 (anyone else get double comments when posting from mobile?)

[matejkramny]

👍

[fyockm]

👍

[jasnell]

@joyent/node-coreteam ... do we want to keep this open here? error message improvements were made in io.js and will come along in the converged stream. It's possible we may want to backport many of those fixes, and it's possible that many more improvements could still be made.

[trevnorris]

I'd just wait until they're converged before backporting.

[jasnell]

Agreed. Closing. Can reopen if folks feel it's worthwhile to backport those changes.