[darcs-devel] [issue757] darcs2 fails to identify the repository on some restrictive http servers.

[David Roundy]

On Sat, Mar 22, 2008 at 05:43:27PM -0000, Nicolas Pouillard wrote:
> With darcs2 doing
> 
>   darcs get http://www.lri.fr/~sozeau/repos/coq/fingertrees
> 
> Shows that asking for the _darcs/format file returns an HTML error since the
> format file doesn't exist.
>
> I would like to help but I don't know what would be the right fix. There is a
> trade-off between reporting parsing errors and conclude that the file is not
> reliable and so fall back to darcs1 repo format.

Darcs handles file-not-found errors just fine.  The problem is that this
server isn't returning a 404 error as it's supposed to, instead it's giving
a 302 response.  I'm not sure what's the best workaround for buggy web
servers.  The simplest fix is to just create a format file on the server,
or perhaps to use a less buggy file server.

If neither of these are reasonable options, I suppose we could try to hack
up some sort of workaround, maybe searching for the text "This page is not
available"... but that's a *seriously* ugly hack.  We can't just ignore
format files that we don't understand, because the entire point of the
format file is that when it's present and we don't understand it, we know
that it's a format we don't understand, and can thus fail with a nice error
message.
-- 
David Roundy
Department of Physics
Oregon State University