infinite redirect loop

[anonymous]

Since trac 0.11.5 redirecting to login-page for anonymous user does not work anymore.

This seems on the first glance like a setup/configuration/plugin issue (AuthRequiredPlugin or PermRedirectPlugin) but after much of trial and investigation i think it's not.

If i compare the apache error_log of an 0.11.4 installation with the same log after upgrading to 0.11.5 the difference becomes obvious.

0.11.4 system, apache error log:

[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121] mod_python (pid=4008, interpreter='main_interpreter', phase='PythonHandler', handler='trac.web.modpython_frontend'): Application error
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121] ServerName: 'socver02.verigy.net'
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121] DocumentRoot: '/users/atsscm/webadmin/htdocs/'
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121] URI: '/trac/TPdev/wiki'
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121] Location: '/trac'
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121] Directory: None
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121] Filename: '/users/atsscm/webadmin/htdocs/trac'
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121] PathInfo: '/TPdev/wiki'
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121] Traceback (most recent call last):
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/mod_python/importer.py", line 1537, in HandlerDispatch\n    default=default_handler, arg=req, silent=hlist.silent)
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/mod_python/importer.py", line 1229, in _process_target\n    result = _execute_target(config, req, object, arg)
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/mod_python/importer.py", line 1128, in _execute_target\n    result = object(arg)
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.4-py2.5.egg/trac/web/modpython_frontend.py", line 149, in handler\n    gateway.run(dispatch_request)
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.4-py2.5.egg/trac/web/wsgi.py", line 87, in run\n    response = application(self.environ, self._start_response)
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.4-py2.5.egg/trac/web/main.py", line 406, in dispatch_request\n    return _dispatch_request(req, env, env_error)
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.4-py2.5.egg/trac/web/main.py", line 463, in _dispatch_request\n    req.chrome['notices'].append(Markup(
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.4-py2.5.egg/trac/web/api.py", line 194, in __getattr__\n    value = self.callbacks[name](self)
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.4-py2.5.egg/trac/web/chrome.py", line 476, in prepare_request\n    for category, name, text in contributor.get_navigation_items(req):
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121]   File "build/bdist.linux-i686/egg/tracauthrequired/authrequired.py", line 60, in get_navigation_items\n    req.redirect(req.href.login(referer = req.abs_href(req.path_info)))
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.4-py2.5.egg/trac/web/api.py", line 318, in redirect\n    raise RequestDone
[Thu Aug 20 16:50:08 2009] [error] [client 10.17.16.121] RequestDone

0.11.5 system, apache error_log:

[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121] mod_python (pid=4553, interpreter='main_interpreter', phase='PythonHandler', handler='trac.web.modpython_frontend'): Application error
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121] ServerName: 'socver02.verigy.net'
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121] DocumentRoot: '/users/atsscm/webadmin/htdocs/'
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121] URI: '/trac/TPdev/wiki'
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121] Location: '/trac'
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121] Directory: None
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121] Filename: '/users/atsscm/webadmin/htdocs/trac'
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121] PathInfo: '/TPdev/wiki'
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121] Traceback (most recent call last):
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/mod_python/importer.py", line 1537, in HandlerDispatch\n    default=default_handler, arg=req, silent=hlist.silent)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/mod_python/importer.py", line 1229, in _process_target\n    result = _execute_target(config, req, object, arg)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/mod_python/importer.py", line 1128, in _execute_target\n    result = object(arg)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.5-py2.5.egg/trac/web/modpython_frontend.py", line 149, in handler\n    gateway.run(dispatch_request)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.5-py2.5.egg/trac/web/wsgi.py", line 92, in run\n    response = application(self.environ, self._start_response)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.5-py2.5.egg/trac/web/main.py", line 414, in dispatch_request\n    return _dispatch_request(req, env, env_error)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.5-py2.5.egg/trac/web/main.py", line 472, in _dispatch_request\n    req.chrome['notices'].append(Markup(
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.5-py2.5.egg/trac/web/api.py", line 195, in __getattr__\n    value = self.callbacks[name](self)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.5-py2.5.egg/trac/web/chrome.py", line 489, in prepare_request\n    for category, name, text in contributor.get_navigation_items(req):
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "build/bdist.linux-i686/egg/tracauthrequired/authrequired.py", line 60, in get_navigation_items\n    req.redirect(req.href.login(referer = req.abs_href(req.path_info)))
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.5-py2.5.egg/trac/web/api.py", line 303, in redirect\n    listener(self, url, permanent)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.5-py2.5.egg/trac/web/chrome.py", line 193, in _save_messages\n    for (i, message) in enumerate(req.chrome[type_]):
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.5-py2.5.egg/trac/web/api.py", line 195, in __getattr__\n    value = self.callbacks[name](self)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.5-py2.5.egg/trac/web/chrome.py", line 489, in prepare_request\n    for category, name, text in contributor.get_navigation_items(req):
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "build/bdist.linux-i686/egg/tracauthrequired/authrequired.py", line 60, in get_navigation_items\n    req.redirect(req.href.login(referer = req.abs_href(req.path_info)))
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.5-py2.5.egg/trac/web/api.py", line 303, in redirect\n    listener(self, url, permanent)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.5-py2.5.egg/trac/web/chrome.py", line 193, in _save_messages\n    for (i, message) in enumerate(req.chrome[type_]):
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.5-py2.5.egg/trac/web/api.py", line 195, in __getattr__\n    value = self.callbacks[name](self)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/site-packages/Trac-0.11.5-py2.5.egg/trac/web/chrome.py", line 489, in prepare_request\n    for category, name, text in contributor.get_navigation_items(req):

...the last 5 lines repeated OFTEN...

[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/logging/__init__.py", line 971, in debug\n    apply(self._log, (DEBUG, msg, args), kwargs)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/logging/__init__.py", line 1101, in _log\n    self.handle(record)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/logging/__init__.py", line 1111, in handle\n    self.callHandlers(record)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/logging/__init__.py", line 1148, in callHandlers\n    hdlr.handle(record)
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/logging/__init__.py", line 653, in handle\n    self.acquire()
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121]   File "/users/atsscm/install/lib/python2.5/logging/__init__.py", line 604, in acquire\n    self.lock.acquire()
[Thu Aug 20 16:54:55 2009] [error] [client 10.17.16.121] RuntimeError: maximum recursion depth exceeded

Trac-0.11.4 terminates the redirection by throwing the 'RequestDone' exception while Trac-0.11.5 calls itself again and again.

The part which seems to me causing the error is: ​http://trac.edgewall.org/browser/tags/trac-0.11.5/trac/web/api.py#L302 which came in with r8271.

[Christian Boos]

With r8217, you meant. Thanks for troubleshooting this.

I think we should check in _save_messages if req.chrome is already there.

[Christian Boos]

This should work…

trac/web/chrome.py

@@ -189 +189 @@
 def _save_messages(req, url, permanent):
     """Save warnings and notices in case of redirect, so that they can
     be displayed after the redirect."""
-    for type_ in ['warnings', 'notices']:
-        for (i, message) in enumerate(req.chrome[type_]):
-            req.session['chrome.%s.%d' % (type_, i)] = message
+    if hasattr(req, 'chrome'): # don't risk a recursion (#8583)
+        for type_ in ['warnings', 'notices']:
+            for (i, message) in enumerate(req.chrome[type_]):
+                req.session['chrome.%s.%d' % (type_, i)] = message
 
 
 class INavigationContributor(Interface):

[Christian Boos]

… this also:

trac/web/chrome.py

@@ -445 +445 @@
 
         chrome = {'links': {}, 'scripts': [], 'ctxtnav': [], 'warnings': [],
                   'notices': []}
-        req.add_redirect_listener(_save_messages)
 
         # This is ugly... we can't pass the real Request object to the
         # add_xxx methods, because it doesn't yet have the chrome attribute
@@ -537 +536 @@
         # Default theme file
         chrome['theme'] = 'theme.html'
 
+        # if we do it earlier we risk a recursion (#8583)
+        req.add_redirect_listener(_save_messages)
+
         return chrome
 
     def get_icon_data(self, req):

Please choose your fix and test ;-)

[Remy Blank]

I'll test it this week-end (I'm on a business trip ATM). The second patch looks nicer ;-)

[anonymous]

Hi Trac-Team!

Sorry for the typo in the mentioned changeset :-| and many thanks for the fast replies!

I've tried both patches.

• The first one results in a endless loop (i had to stop apache to terminate it)
  apache logs didn't show anything, trac.log was permanently increasing (loop between auth-required-plugin and trac-chrome)
• The second one redirects as expected (seen in the logs) but i still get 'Internal Server Error' from apache. Maybe the exception is not caught and passed to mod_python/apache even when everything went well?

With best regards,

Klaus

PS : Trac is a really cool tool. I like the concept and extendability very much. It's of great value for our projects.

[Remy Blank]

I believe the second fix is the correct one (applied in [8506]). With that, the PermRedirectPlugin works again. OTOH, the AuthRequiredPlugin is broken beyond repair, as it tries to redirect at a very inconvenient time (in get_navigation_items(), which is called by Chrome.prepare_request(), which is itself called from main._dispatch_request() while registering the message saying that the user should log in).

[anonymous]

The patch together with the PermRedirectPlugin works as expected.
I'll switch over to it and drop the AuthRequiredPlugin.

Many thanks for your support!

With best regards,

Klaus

[anonymous]

I am running 0.11.5 with the [8506] patch applied. the permredirect stuff appears to work as expected, but I still get an infinite redirect loop on /prefs/account if a user requests a password reset and then logs in.

[anonymous]

nevermind, this appears to be ​th:#3233.