Hey, I’m trying to upgrade to pants 1.16 for a project I’m working on (I’m working on a python2->3 migration so it’s the highest version I can use right now). When I try to run

pants compile ::

it fails with `Problem launching via NailgunClient`and

TruncatedHeaderError(u"Failed to read nailgun chunk header...

Do you have any thoughts on how I can go about debugging this? I think I want to see what the nailgun server is up to, but I’m not sure how to get my hands on its output.

Do you have custom pants backend code in your repo? Because if not then you should be able to use the most current version of pants - it requires python3 to run itself, but it can operate on python2 code.

We are on 1.7, so moving to 1.16 is a win 🙂 . Our laptops dont have a consistent py3 install, hence moving to the latest pants that still runs on py2. Yep we have custom

backend_packages

for play, s3cache, and a few other things. The annoying part is that it passes locally but not in travis, so would be great if there was extra debugging info it could spit out beyond this: https://gist.github.com/MasterDDT/f92a1f7999c421245abda0a4b8682ef3

the output from the nailgun server will be written under

.pants.d/ng/**

, iirc... so would want to look for sever failures there