Empty XMLRPC response from launchpad

[Gavin Panella]

On Wed, 28 Oct 2009 15:51:59 +0000 (UTC)
Gordon Tyler <gordon at doxxx.net> wrote:

> Gordon Tyler <gordon <at> doxxx.net> writes:
> 
> > 
> > Gavin Panella <gavin.panella <at> canonical.com> writes:
> > 
> > > On Tue, 27 Oct 2009 21:00:19 +0000 (UTC)
> > > Gordon Tyler <gordon <at> doxxx.net> wrote:
> > > 
> > > > I'm trying fix bug #186920 by using a modified form of Bill Bumgarner's 
> > > > HTTPTransport (python bug #648658) for xmlrpclib which allows it to use 
> > urllib2 
> > > > and thus an HTTP proxy, but I'm having a problem where the XMLRPC reply 
> from 
> > > > launchpad is just an empty page.
> > > 
> > > Is this still happening? Launchpad had a brown-out last night at about
> > > the time of your email, and I noticed issues pulling branches at that
> > > time, with XML-RPC related error messages. Maybe it's just Launchpad
> > > and not your code.
> > 
> > I've had this problem since I started working on the bug last week. I'm going 
> to 
> > try running my code from an non-firewalled host to see if its the web proxy 
> that 
> > is the problem.
> 
> Running from a non-firewalled host works when the http_proxy is not set. This is 
> not unexpected since it's using the unaltered HTTP codepath for xmlrpclib. 
> However, once I install a web proxy on the same host and set http_proxy to point 
> to it, I get a different problem: A 302 response which redirects to the same URL 
> that was requested, causing the HTTP client to fail with an infinite redirect 
> loop error.

I can't promise that this will help in your case, but there is an
XML-RPC transport in Launchpad that we use to work through proxies:

http://bazaar.launchpad.net/~launchpad-pqm/launchpad/devel/annotate/head%3A/lib/lp/bugs/externalbugtracker/xmlrpc.py

It's used all the time, every day, so it works, but it might not be
suitable for you. The code says "this transport isn't fit for general
XML-RPC use", but it might be useful to help isolate the issue you've
been seeing.

Gavin.