Reproducible hang in busboy

I’ve been investigating an occasional hang in our application, and tracked it down to what appears to be a busboy issue. There is a test case (client and server) in this repository. See the README in that repository for instructions and some discussion. A couple of key points from there:

• The problem only seems to occur when using the .pipe() method of the file object. Listening for data and end events works as expected, without hanging.
• It seems to depend on how the request is split across TCP/IP packets. Sending the terminator string in the same chunk as the final field also makes it work without hanging.

Issues of this sort seem to have been reported before (e.g. #116, mscdex/connect-busboy#15; probably others) without any resolution being reached. I hope having a simple test case will make it easier to find the root cause.

[mscdex]

Thanks for repro repo! I ended up at the same conclusion as you, however I made the fix in a slightly different place because a file.push(null) may not translate to 'end' being emitted immediately if the file stream is paused IIRC, so it may not be safe to resume parsing until we see 'end'.

[jaydenseric]

@mscdex thanks for the quick fix, graphql-upload consumers had noticed this subtle issue but we couldn’t pin it down at the time.

But why is this release semver v0.3.0 instead of v0.2.15?

And could you please release v1.0.0. Consumers won’t get fixes like this without every library author manually changing their busboy v0.x dependency and publishing a new release: