diskimage-builder/doc/source/elements.rst

Elements
========

Elements are found in the subdirectory elements. Each element is in a directory
named after the element itself. Elements *should* have a README.rst in the root
of the element directory describing what it is for.

.. toctree::
   :glob:

   diskimage_builder/elements/*/*
Split out README into separate files This makes the docs site a lot more manageable and begins moving us in the direction of separate user and developer docs. Change-Id: I1650ef9d5be1733b8bc118d99090143cb5b06102 2015-02-12 07:07:47 +00:00			`Elements`
			`========`

			`Elements are found in the subdirectory elements. Each element is in a directory`
			`named after the element itself. Elements should have a README.rst in the root`
			`of the element directory describing what it is for.`

			`.. toctree::`
			`:glob:`

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 2016-09-09 03:11:52 +00:00			`diskimage_builder/elements//`