zc.buildout randomly broke during routine patch today

Question

Deploying a security patch to a production machine today and zc.buildout just randomly breaks. I already tried to upgrade pip and this still doesn't resolve the issue.

$ ./bin/buildout 
mr.developer: Queued 'django-appregister' for checkout.
mr.developer: Queued 'django-countries' for checkout.
mr.developer: Queued 'django-mailer' for checkout.
mr.developer: Queued 'django-ostinato' for checkout.
mr.developer: Skipped checkout of existing package 'django-appregister'.
mr.developer: Skipped checkout of existing package 'django-countries'.
mr.developer: Skipped checkout of existing package 'django-mailer'.
mr.developer: Skipped checkout of existing package 'django-ostinato'.
Develop: '/home/evopoints/webapp/src/django-ostinato'
/usr/lib/python2.7/dist-packages/setuptools/dist.py:364: UserWarning: Normalizing '1.1.beta' to '1.1b0'
normalized_version,
warning: no previously-included files matching '*.pyc' found anywhere in distribution
Develop: '/home/evopoints/webapp/src/django-mailer'
Develop: '/home/evopoints/webapp/src/django-countries'
Develop: '/home/evopoints/webapp/src/django-appregister'
/usr/lib/python2.7/dist-packages/setuptools/dist.py:364: UserWarning: Normalizing '0.4.dev' to '0.4.dev0'
normalized_version,
Unused options for buildout: 'include-site-packages' 'unzip'.
Updating _mr.developer.
Installing python.
While:
Installing python.

An internal error occurred due to a bug in either zc.buildout or in a
recipe being used:
Traceback (most recent call last):
File "/home/evopoints/webapp/eggs/zc.buildout-2.9.4-py2.7.egg/zc/buildout/buildout.py", line 2123, in main
    getattr(buildout, command)(args)
File "/home/evopoints/webapp/eggs/zc.buildout-2.9.4-py2.7.egg/zc/buildout/buildout.py", line 796, in install
    installed_files = self[part]._call(recipe.install)
File "/home/evopoints/webapp/eggs/zc.buildout-2.9.4-py2.7.egg/zc/buildout/buildout.py", line 1553, in _call
    return f()
File "/home/evopoints/webapp/eggs/zc.recipe.egg-2.0.3-py2.7.egg/zc/recipe/egg/egg.py", line 126, in install
    reqs, ws = self.working_set()
File "/home/evopoints/webapp/eggs/zc.recipe.egg-2.0.3-py2.7.egg/zc/recipe/egg/egg.py", line 84, in working_set
    allow_hosts=self.allow_hosts)
File "/home/evopoints/webapp/eggs/zc.buildout-2.9.4-py2.7.egg/zc/buildout/easy_install.py", line 913, in install
    return installer.install(specs, working_set)
File "/home/evopoints/webapp/eggs/zc.buildout-2.9.4-py2.7.egg/zc/buildout/easy_install.py", line 657, in install
    for spec in specs]
File "/usr/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 2879, in parse
    req, = parse_requirements(s)
ValueError: need more than 0 values to unpack

Why does this happen at random times? (It's not the first time) This is now at the point that I'm going to have to move away from buildout entirely, because it's too unreliable, for a client production site to randomly fail during a small patch in he's site code.

It's random time, but is the traceback always the same? If so,you can expect that the data sent to the module is causing this. Can't you look at commonalities in inputs? It says that it has no values to unpack. So there must be something that is not where it should be. — Ando Jurai, Aug 01 '17 at 10:16
@AndoJurai I literally ran the exact same buildout script last week (Friday), with no issues. The only thing that is in this patch is a new html file. Build scripts are still the same, deployment scripts are also still the same. — Andre, Aug 01 '17 at 10:25

ndpu · Answer 1 · 2018-12-19T14:55:19.713

0

Changing interpreter option to python2.7 from python helped me in similar situation:

[buildout]
parts =
  python

[python]
# ...
interpreter = python2.7

edited Dec 19 '18 at 14:55

answered Dec 19 '18 at 14:49

ndpu

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score 0 · Accepted Answer · answered Dec 20 '18 at 14:42

If you run buildout with -vvvv, you might see the actual error. The "need more than 0 values to unpack" error, in my experience, sometimes occurs when there's an error downloading something.

What could also help is to upgrade your versions of setuptools and zc.buildout (2.12.0 is out, you're using 2.9.4). There have been quite a number of fixes to buildout to compensate for changes in the environment (most often changes in setuptools).

Note that pypi also moved. From http to https, and from pypi.python.org to pypi.org. So adjusting your index= line (if you have it) might save a bunch of redirects, which could also work.

I haven't seen any serious breakage in buildout in the last few months, at least the github issue tracker has been quiet :-)

It's been a while now and I'm not sure why I never marked this as resolved; But if I remember correctly this was indeed the cause of the issue. I had to tell buildout to change the `index` as you indicated. — Andre, May 02 '21 at 23:25

zc.buildout randomly broke during routine patch today

2 Answers2