History

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
..
extra-data.d	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

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

extra-data.d

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

README.rst

install-types

Enable install-types support for elements.

Install types permit elements to be installed from different sources, such as git repositories, distribution packages, or pip. The default install type is 'source' but it can be modified on the disk-image-create command line via the --install-type option. For example you can set:

--install-type=package

to enable package installs by default. Alternately, you can also set DIB_DEFAULT_INSTALLTYPE.

Many elements expose different install types. The different implementations live under <install-dir-prefix>-<install-type>-install directories under an element's install.d. The base element enables the chosen install type by symlinking the correct hook scripts under install.d directly. <install-dir-prefix> can be a string of alphanumeric and '-' characters, but typically corresponds to the element name.

For example, the nova element would provide:

nova/install.d/nova-package-install/74-nova nova/install.d/nova-source-install/74-nova

The following symlink would be created for the package install type:

install.d/74-nova -> nova-package-install/74-nova

Or, for the source install type:

install.d/74-nova -> nova-source-install/74-nova

All other scripts that exist under install.d for an element will be executed as normal. This allows common install code to live in a script under install.d.

Environment Variables

DIB_INSTALLTYPE<install_dir_prefix>

Required: No
Default: source
Description: Set the install type for the dir prefix. '-' characters can be replaced with a '_'.
Example: DIB_INSTALLTYPE_simple_init=repo Sets the simple-init element install type to be repo.