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
Diskimage-builder currently writes cloud-init config file which adds a
host entry mapping the hostname and FQDN to 127.0.0.1 into every image
built. This is probably useful for some use cases but not for all, so we
now allow customizing the manage_etc_hosts value via
DIB_CLOUD_INIT_ETC_HOSTS variable and also not writing the config at all
if that variable is explicitly set to an empty string (currently the
default is 'localhost' but in the future the default will be empty
string).
Particular description of the problem this causes in TripleO follows:
We get hosts files like this:
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
127.0.0.1 ov-rl5i5saoc6h-1-hj5tzsbrdv4c-controller-dy6nuyarqy5z.novalocal ov-rl5i5saoc6h-1-hj5tzsbrdv4c-controller-dy6nuyarqy5z
# HEAT_HOSTS_START - Do not edit manually within this section!
192.0.2.17 ov-rl5i5saoc6h-0-wfzcsrqo34p6-controller-m3hy26lhxavl ov-rl5i5saoc6h-0-wfzcsrqo34p6-controller-m3hy26lhxavl.novalocal
192.0.2.15 ov-rl5i5saoc6h-1-hj5tzsbrdv4c-controller-dy6nuyarqy5z ov-rl5i5saoc6h-1-hj5tzsbrdv4c-controller-dy6nuyarqy5z.novalocal
192.0.2.16 ov-rl5i5saoc6h-2-a6v7saxnivm5-controller-7jboskte34r7 ov-rl5i5saoc6h-2-a6v7saxnivm5-controller-7jboskte34r7.novalocal
# HEAT_HOSTS_END
The duplicate hostname/FQDN entry for 127.0.0.1 and 192.0.2.15 confuses
Corosync, which then fails to start a cluster when using hostnames in
the config file instead of IPs.
Change-Id: Ia8582883f737548e2911d3f36a1943e5b236281b
Partial-Bug: #1447497
