97c01e48ed
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 |
||
---|---|---|
.. | ||
extra-data.d | ||
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.