This was originally required to allow other methods in SourcesList to
fail, but subsequent changes rendered that unnecessary, and it's just
a cleanup now, and avoids passing in module separately to save().
1. Don't test check_mode in both the caller and in the callee.
2. Don't test HAVE_PYTHON_APT inside an if that tests HAVE_PYTHON_APT
3. Don't be irritatingly vague about why the module fails ("You may be
seeing this because…").
Note that if «apt-get -y install python-apt» succeeds with rc==0, but
for some reason python_apt is not usable afterwards, this will break
because the imports in install_python_apt aren't wrapped inside a
try/except.
In other words, we assume that install_python_apt either succeeds or
fails with a traceback. This commit doesn't affect that behaviour.
Some things cannot be updated via the API, so check for those and fail
if the user is wanting to update them. Also don't try to update ipv6
stuff, as that doesn't work and will cause a traceback.
If `docker.__version__` contains non-digit characters, such as:
>>> import docker
>>> docker.__version__
'1.4.0-dev'
Then `get_docker_py_versioninfo` will fail with:
ValueError: invalid literal for int() with base 10: '0-de'
This patch corrects the parsing of the version string so that
`get_docker_py_versioninfo` in this example would return:
(1, 4, 0, '-dev')
If `password` is defined as `*` `useradd` or `usermod` returns an error:
msg: usermod: Invalid password: `*'
This works very well on Linux host to not define any password for a
user (mainly useful if your setup is only based on SSH keys for
auth). On OpenBSD this does not work, so we have to ignore the encrypted
password parameter if it defined as `*`.