NixOS/nixpkgs — pull request #108 by aszlig (2012-08-17 11:01:40+00:00)
Title: chromium: Improve update script and update to latest versions.

Previously, we had a single hash of the whole version response from omahaproxy.

Unfortunately the dev version is released quite frequently, so the hash is of no use at all (we could rather directly fetch rather than executing the script, because it will fetch **all** channels anyway).

This pull request adds two methods of caching:

* First of all, if a perticular version/channel is already in the previous version of the sources.nix file, don't download it again.

* And the second method is to check if the current sha256 is already downloaded and reads the corresponding sha256 from the lookup table.

So, this should really help to avoid flooding the download servers and to not stress impatient users too much.