diskimage-builder/diskimage_builder/elements/centos-minimal
Ian Wienand 97c01e48ed Move elements & lib relative to diskimage_builder package
Currently we have all our elements and library files in a top-level
directory and install them into
<root>/share/diskimage-builder/[elements|lib] (where root is either /
or the root of a virtualenv).

The problem with this is that editable/development installs (pip -e)
do *not* install data_files.  Thus we have no canonical location to
look for elements -- leading to the various odd things we do such as a
whole bunch of guessing at the top of disk-image-create and having a
special test-loader in tests/test_elements.py so we can run python
unit tests on those elements that have it.

data_files is really the wrong thing to use for what are essentially
assets of the program.  data_files install works well for things like
config-files, init.d files or dropping documentation files.

By moving the elements under the diskimage_builder package, we always
know where they are relative to where we import from.  In fact,
pkg_resources has an api for this which we wrap in the new
diskimage_builder/paths.py helper [1].

We use this helper to find the correct path in the couple of places we
need to find the base-elements dir, and for the paths to import the
library shell functions.

Elements such as svc-map and pkg-map include python unit-tests, which
we do not need tests/test_elements.py to special-case load any more.
They just get found automatically by the normal subunit loader.

I have a follow-on change (I69ca3d26fede0506a6353c077c69f735c8d84d28)
to move disk-image-create to a regular python entry-point.

Unfortunately, this has to move to work with setuptools.  You'd think
a symlink under diskimage_builder/[elements|lib] would work, but it
doesn't.

[1] this API handles stuff like getting files out of .zip archive
modules, which we don't do.  Essentially for us it's returning
__file__.

Change-Id: I5e3e3c97f385b1a4ff2031a161a55b231895df5b
2016-11-01 17:27:41 -07:00
..
environment.d Move elements & lib relative to diskimage_builder package 2016-11-01 17:27:41 -07:00
test-elements/build-succeeds Move elements & lib relative to diskimage_builder package 2016-11-01 17:27:41 -07:00
yum.repos.d Move elements & lib relative to diskimage_builder package 2016-11-01 17:27:41 -07:00
element-deps Move elements & lib relative to diskimage_builder package 2016-11-01 17:27:41 -07:00
element-provides Move elements & lib relative to diskimage_builder package 2016-11-01 17:27:41 -07:00
README.rst Move elements & lib relative to diskimage_builder package 2016-11-01 17:27:41 -07:00

==============
centos-minimal
==============
Create a minimal image based on CentOS 7.

Use of this element will require 'yum' and 'yum-utils' to be installed on
Ubuntu and Debian. Nothing additional is needed on Fedora or CentOS.

The `DIB_OFFLINE` or more specific `DIB_YUMCHROOT_USE_CACHE`
variables can be set to prefer the use of a pre-cached root filesystem
tarball.

By default, `DIB_YUM_MINIMAL_CREATE_INTERFACES` is set to enable the
creation of `/etc/sysconfig/network-scripts/ifcfg-eth[0|1]` scripts to
enable DHCP on the `eth0` & `eth1` interfaces.  If you do not have
these interfaces, or if you are using something else to setup the
network such as cloud-init, glean or network-manager, you would want
to set this to `0`.