update-manager silently ignores HTTP 403 on meta-release

[Ian Jackson]

Binary package hint: update-manager

I was attempting to use update-manager to upgrade a hardy desktop i386 install to intrepid. We enabled "show updates to normal releases" and did "check for updates" but no new release was advertised.

On checking the log on the squid web cache on the local LAN to see what update-manager was trying to download, I saw this:

1266165386.331 24 172.18.45.45 TCP_DENIED/403 1584 GET http://changelogs.ubuntu.com/meta-release - NONE/- text/html

Ie, the a mistake in my proxy configuration was preventing update-manager from fetching the meta-release file (although the ordinary upgrade files were fine).

The bug I am reporting here is that update-manager should have complained, with an error message of some kind, about the 403 HTTP error fetching the meta-release file. The user needs to know the difference between "there is no new release available" and "the update system is broken".

Steps to reproduce:
 * install squid on a convenient machine on the LAN
 * configure squid to deny requests to changelogs.ubuntu.com
 * install hardy, configuring it to use a squid proxy
 * run update-manager from the command line or menu
 * say "check for updates"
 * observe that the upgrade to Intrepid is not offered and no error message is displayed

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.