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
2.5 KiB
pypi
Inject a PyPI mirror
Use a custom PyPI mirror to build images. The default is to bind mount one from ~/.cache/image-create/pypi/mirror into the build environment as mirror URL file:///tmp/pypi. The element temporarily overwrites /root/.pip.conf and .pydistutils.cfg to use it.
When online, the official pypi.python.org pypi index is supplied as an extra-url, so uncached dependencies will still be available. When offline, only the mirror is used - be warned that a stale mirror will cause build failures. To disable the pypi.python.org index without using --offline (e.g. when working behind a corporate firewall that prohibits pypi.python.org) set DIB_NO_PYPI_PIP to any non-empty value.
To use an arbitrary mirror set DIB_PYPI_MIRROR_URL=http[s]://somevalue/
Additional mirrors can be added by exporting DIB_PYPI_MIRROR_URL_1=... etc. Only the one mirror can be used by easy-install, but since wheels need to be in the first mirror to be used, the last listed mirror is used as the pydistutils index. NB: The sort order for these variables is a simple string sort - if you have more than 9 additional mirrors, some care will be needed.
You can also set the number of retries that occur on failure by setting the DIB_PIP_RETRIES environment variable. If setting fallback pip mirrors you typically want to set this to 0 to prevent the need to fail multiple times before falling back.
A typical use of this element is thus: export DIB_PYPI_MIRROR_URL=http://site/pypi/Ubuntu-13.10 export DIB_PYPI_MIRROR_URL_1=http://site/pypi/ export DIB_PYPI_MIRROR_URL_2=file:///tmp/pypi export DIB_PIP_RETRIES=0
[devpi-server](https://git.openstack.org/cgit/openstack-infra/pypi-mirro://pypi.python.org/pypi/devpi-server) can be useful in making a partial PyPI mirror suitable for building images. For instance:
- pip install -U devpi
- devpi-server quickstart
- devpi use http://machinename:3141
Re-export your variables to point at the new mirror:
export DIB_PYPI_MIRROR_URL=http://machinename:3141/ unset DIB_PYPI__MIRROR_URL_1 unset DIB_PYPI__MIRROR_URL_2
The next time packages are installed, they'll be cached on the local devpi server; subsequent runs pointed at the same mirror will use the local cache if the upstream can't be contacted.
Note that this process only has the server running temporarily; see [Quickstart: Permanent install on server/laptop](http://doc.devpi.net/latest/quickstart-server.html) guide from the devpi developers for more information on a more permanent setup.