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 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. 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://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 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](https://devpi.net/docs/devpi/devpi/latest/+d/quickstart-server.html) guide from the devpi developers for more information on a more permanent setup.