Tom Gross: Workaround setuptools 8.0 bug with zc.buildout

Buildout always fetches the latest version of setuptools for bootstraping. No matter what is defined in versions.cfg. It is possible to set the version of zc.buildout when bootstraping but not the one of setuptools.

This behavior is hardcoded in bootstrap.py.

77 ez = {}
78 exec(urlopen('https://bootstrap.pypa.io/ez_setup.py'
79             ).read(), ez)
80 if not options.allow_site_packages:

Unfortunately there are some incompatible changes (a bug?) in setuptools 8.0 which prevent zc.buildout from bootstraping. It fails with the following error:

tom@localhost:~/demobuildout> python2.7 bootstrap.py
Downloading https://pypi.python.org/packages/source/s/setuptools/setuptools-8.0.zip
Extracting in /tmp/tmp_34LbA
Now working in /tmp/tmp_34LbA/setuptools-8.0
Building a Setuptools egg in /tmp/tmpeA5PHB
/tmp/tmpeA5PHB/setuptools-8.0-py2.7.egg
Traceback (most recent call last):
  File "bootstrap.py", line 145, in <module>
    if _final_version(distv):
  File "bootstrap.py", line 131, in _final_version
    for part in parsed_version:
TypeError: 'Version' object is not iterable

I found a quite easy workaround to use a different version of setuptools until this issue is fixed. Setuptools 7.0 seems to work fine. Do the following:

1. Create a directory and change to it:

   $ mkdir setuptools-workaround
   $ cd setuptools-workaround
   

2. Download ez_setup.py:

   $ wget https://bootstrap.pypa.io/ez_setup.py
   

3. Edit ez_setup.py and change the setuptools version to be used.:

   39 DEFAULT_VERSION = "7.0"
   40 DEFAULT_URL = "https://pypi.python.org/packages/source/s/setuptools/"

4. Start a python webserver in the directory.:

   $ python -m SimpleHTTPServer
   

   The server does not daemonize itself. The following actions need to be done in a new terminal.

5. Now change the line where it downloads ez_setup.py in your bootstrap.py file to use the patched ez_setup.py.:

   77 ez = {}
   78 exec(urlopen('http://localhost:8000/ez_setup.py'
   79             ).read(), ez)
   80 if not options.allow_site_packages:
   

6. You are ready to start your working buildout.

   tom@linux-zoc2:~/demobuildout> python bootstrap.py
   Downloading https://pypi.python.org/packages/source/s/setuptools/setuptools-7.0.zip
   Extracting in /tmp/tmp82Jp3m
   Now working in /tmp/tmp82Jp3m/setuptools-7.0
   Building a Setuptools egg in /tmp/tmpgDuB3k
   /tmp/tmpgDuB3k/setuptools-7.0-py2.7.egg
   Generated script '/home/tom/demobuildout/bin/buildout'.
   

This works for me. Hope this bug is fixed soon anyway.