Hi group, I have an interesting problem on my server with mod_wsgi and mod_fcgid, this is an update of a posting I did on the mod_wsgi list, see http://groups.google.com/group/modwsgi/browse_thread/thread/f7171b7442965c78# for the full thread. The mod_wsgi developers had no explanation for the effect so I crosspost here with some updates. I run trac and subversion in the same configuration and on the same vhost, see http://ktk.netlabs.org/misc/svn.netlabs.conf for my configuration. The configuration starts with the SVN repositories residing on /repos and then configures trac with mod_wsgi. So far this used to work just fine for many years. As you can see on http://svn.netlabs.org I run a lot of TRAC repositories for several OSS projects. A few weeks ago I upgraded subversion on the server to version 1.7, since then I can still checkout and commit to svn repositories with clients which are below version 1.7 (I tested 1.6.x), everything works as expected. However, any subversion client >= 1.7 cannot _commit_ anymore, checkout works as before though. After dumping with tcpdump I could see the following packet (decoded TCP stream via wireshark, Subversion 1.7.x client): -- POST /repos/sandbox/!svn/me HTTP/1.1 User-Agent: SVN/1.7.3 neon/0.29.6 Connection: TE TE: trailers Host: svn.netlabs.org Content-Type: application/vnd.svn-skel DAV: http://subversion.tigris.org/xmlns/dav/svn/depth DAV: http://subversion.tigris.org/xmlns/dav/svn/mergeinfo DAV: http://subversion.tigris.org/xmlns/dav/svn/log-revprops Content-Length: 14 Accept-Encoding: gzip ( create-txn )HTTP/1.1 404 Not Found Date: Thu, 22 Mar 2012 20:38:39 GMT Server: Apache Content-Length: 21 Content-Type: text/plain Environment not found -- full decoded TCP stream: http://pastebin.com/4bAT2TMA tcpdump: http://ktk.netlabs.org/misc/subversion-commit_17.dmp This "Environment not found" is definitely an error message from TRAC in case there is no trac environment found. So for some reason mod_wsgi hits in at this point instead of the DAV handler. Again, this works just fine with subversion 1.6.x (it does not do a POST there though): full decoded TCP stream: http://pastebin.com/X9J3k7kE tcpdump: http://ktk.netlabs.org/misc/subversion-commit_16.dmp >From the subversion changelog I can see that they changed the way subversion interacts with the server: http://subversion.apache.org/docs/release-notes/1.7.html#httpv2 -- Subversion 1.7 offers a simpler HTTP protocol variant that can be used when connecting to supported servers. This simpler protocol (sometimes referred to as HTTPv2) requires fewer client-server round trips to establish a connection, making Subversion much more performant on high- latency network connections. As mentioned in the compatibility table, Subversion 1.7 will only use HTTPv2 when connecting with a 1.7 (or greater) server, but will continue to use existing protocols when communicating with earlier versions of Subversion. Likewise, older clients will only use the old protocol when connecting to a Subversion server, regardless of version. -- So the only explanation I have is that with 1.7 clients subversion tries to do HTTPv2 and for some reason mod_wsgi decides to take over even if it's not its job because the post goes to /repos, which should be the DAV handler. Note that I can "fix" the issue if I deactivate mod_wsgi or mod_fcgid with the current subversion configuration so the subversion module itself seems to work fine with new clients as well. I first suspected a bug in mod_wsgi, for that reason I changed the configuration to mod_fcgid. Unfortunately it behaves exactly like that so my next guess (with the limited understanding of Apache internals I have) would be a bug in the internal processing of Apache. Software versions (running on FreeBSD 8): ap22-mod_wsgi-3.3_2 apache-2.2.22_5 py26-subversion-1.7.3 subversion-1.7.3 trac-0.12.3 python26-2.6.7_3 content of trac-netlabs.wsgi (looks a bit different for mod_fcgid but as I said same bug): -- #!/usr/local/bin/python2.6 # -*- coding: utf-8 -*- import os def application(environ, start_request): os.environ['TRAC_ENV_PARENT_DIR'] = '/data/trac/netlabs.org' os.environ['PYTHON_EGG_CACHE'] = '/tmp/egg-cache' from trac.web.main import dispatch_request environ['trac.locale'] = 'sv_SE.UTF-8' return dispatch_request(environ, start_request) -- If someone wants to try committing, there is a sandbox repository which is world read/writable at: http://svn.netlabs.org/repos/sandbox/ I'm more than happy to run more tests if someone has some ideas, I ran out of them. thanks Adrian -- Adrian Gschwend @ netlabs.org ktk [a t] netlabs.org ------- Open Source Project http://www.netlabs.org --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx
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