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 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 index without using –offline (e.g. when working behind a corporate firewall that prohibits 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]( can be useful in making a partial PyPI mirror suitable for building images. For instance:

  • 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]( guide from the devpi developers for more information on a more permanent setup.