Initial packaging of the extrepo-data

In its current form, extrepo goes fetching the repository data from pages.debian.net. However, if one modifies config.yaml, it's possible to configure extrepo this way:

url: file:///usr/share/extrepo/offline-data

the result is that extrepo will fetch all of the data from local files. The only thing that's really needed, is an offline version of all of the extrepo data that are normally hosted in pages.debian.net. This merge request is about that: providing an offline, packaged version, of the repositories data.

Having offline repositories information is interesting in many ways: 1/ If Salsa is down, like it did for more than 48 hours last week-end, using the packaged version is a good alternative. I don't like the fact Salsa is a SPOF... 2/ If a computer has no internet access, but still would like to install external repositories using local mirrors.

For 2/, we're thinking about adding an option in extrepo, so one may specify an alternative mirror URL. So we (myself and my colleague) are working on adding such an option to extrepo itself, and we will provide a merge request "soon".

We do have a direct application for this, when setting-up OpenStack: I would like to benefit from the authentication ability of extrepo, but using my own mirrors. Our OpenStack nodes, for security reasons, are always offline, and can only access package mirrors.

Wouter, if you don't have time to maintain this, I am happy to maintain the packaging by myself only, though I'd love to co-maintain it with you. My intention is to maintain this this in the official Stable backports repository.

Cheers,

Thomas Goirand (zigo)