Question

Whenever I click PREVIEW after I've edited a topic I get an error that says "topics cannot be empty." If I click back then PREVIEW again, it usually works. It most frequently happens on the first edit in a new browser. Does this mean I'm sending undefined data every time? And if so, how do I change it?

Also, sometimes after I preview the changes and click SAVE, I get another error that says "Save function cannot be used in this manner" but if I click back and SAVE again it usually works.

We have another server running an almost identicle setup. The main difference is the one that's having the problem also uses mod_perl v1.29

Thanks in advance.

Environment

-- PaulRyan - 22 Jun 2004

Answer

First time I read this; not sure what causes this. You can probably fix that by running preview and save in regular cgi-mode, not mod_perl. It mainly pays off to run only the view script under mod_perl.

-- PeterThoeny - 28 Jun 2004

I followed the instructions according to ModPerlOnRedHat90, but changed the FilesMatch from ^(view|preview) to just ^(view). However now I simply get a "500 Internal Server Error" The error_log is below and the Registry.pm is in one of the locations recognized by @INC in perl. Any other suggestions? Thanks.

Undefined subroutine &ModPerl::Registry::handler called.\n
[Mon Jun 28 11:27:05 2004] [notice] cannot use a full URL in a 401 ErrorDocument directive --- ignoring!
[Mon Jun 28 11:27:05 2004] [error] Can't locate ModPerl/Registry.pm in @INC (@INC contains: /usr/local/src/mod_perl-1.29/lib/Apache/ 
/home/httpd/twiki/bin /usr/lib/perl5/5.8.0/i386-linux-thread-multi
/usr/lib/perl5/5.8.0 /usr/lib/perl5/site_perl/5.8.0/i386-linux-thread-multi 
/usr/lib/perl5/site_perl/5.8.0 /usr/lib/perl5/site_perl /usr/lib/perl5/vendor_perl/5.8.0/i386-linux-thread-multi 
/usr/lib/perl5/vendor_perl/5.8.0 /usr/lib/perl5/vendor_perl /usr/lib/perl5/5.8.0/i386-linux-thread-multi 
/usr/lib/perl5/5.8.0 . /usr/local/apache/ /usr/local/apache/lib/perl) at (eval 10) line 3.\n
[Mon Jun 28 11:27:05 2004] [error] Undefined subroutine &ModPerl::Registry::handler called.\n
[root@hornbeam conf]# slocate Registry.pm
/usr/lib/perl5/5.8.0/i386-linux-thread-multi/Registry.pm
/usr/lib/perl5/site_perl/5.8.0/i386-linux-thread-multi/Apache/Registry.pm
/usr/local/src/mod_perl-1.29/lib/Apache/Registry.pm

-- PaulRyan - 28 Jun 2004

Regarding the June 28th post, the problem seems to be the line PerlHandler was reading ModPerl::Registry instead of Apache::Registry.

 <FilesMatch "^(view)$">
          SetHandler perl-script
          PerlHandler Apache::Registry
          Options ExecCGI
          PerlSendHeader On
        </FilesMatch>

Yet I haven't gotten any further on this issue. I did a complete reinstall (OS, Apache, etc) because the modules that I was compiling showed up garbled regardless of error-free compilations. Yet, I'm still getting the same error with Preview. Additionally I sometimes get URI is too long errors. I checked my apache logs: error_log shows

[Wed Jul  7 16:41:07 2004] [notice] caught SIGTERM, shutting down
[Wed Jul  7 16:41:40 2004] [notice] Apache/1.3.31 (Unix) mod_perl/1.29 configured -- resuming normal operations
[Wed Jul  7 16:41:40 2004] [notice] Accept mutex: sysvsem (Default: sysvsem)
[Wed Jul  7 16:41:55 2004] [notice] cannot use a full URL in a 401 ErrorDocument directive --- ignoring!
[Wed Jul  7 16:41:56 2004] null: Use of uninitialized value in string ne at /www/html/twiki/bin/view line 427.
[Wed Jul  7 16:41:56 2004] null: print() on closed filehandle FILE at /www/html/twiki/lib//TWiki/Store.pm line 667.
[Wed Jul  7 16:41:56 2004] null: print() on closed filehandle FILE at /www/html/twiki/lib//TWiki/Store.pm line 667.
[Wed Jul  7 16:42:00 2004] [notice] cannot use a full URL in a 401 ErrorDocument directive --- ignoring!
[Wed Jul  7 16:42:00 2004] null: Use of uninitialized value in string ne at /www/html/twiki/bin/view line 427.
[Wed Jul  7 16:42:00 2004] null: print() on closed filehandle FILE at /www/html/twiki/lib//TWiki/Store.pm line 667.

While the access_log appears to be trying to shove everything in the edit field into the URL field

[07/Jul/2004:16:42:03 -0500] "GET /twiki/pub/TWiki/SlideShowPlugin/startpres.gif HTTP/1.1" 200 2065
192.168.29.35 - - [07/Jul/2004:16:42:06 -0500] "GET /twiki/bin/edit/Sandbox/PaulRyanTest?t=1089236523 HTTP/1.1" 401 409
192.168.29.35 - PaulRyan [07/Jul/2004:16:42:11 -0500] "GET /twiki/bin/edit/Sandbox/PaulRyanTest?t=1089236523 HTTP/1.1" 200 5674
192.168.29.35 - - [07/Jul/2004:16:42:11 -0500] "GET /twiki/pub/TWiki/TWikiLogos/twikiRobot46x50.gif HTTP/1.1" 304 -
192.168.29.35 - - [07/Jul/2004:16:42:20 -0500] "POST /twiki/bin/preview/Sandbox/PaulRyanTest HTTP/1.1" 401 409
192.168.29.35 - PaulRyan [07/Jul/2004:16:42:20 -0500] "text=---%2B%2B%2B%2BGauge+Test%0D%0Athis+is+to+see+if+a+gauge+works.%0D%0A%0D%0A%25GAUGE%7B+type%3D%22tambar%22+name%3D%22t1%22+scale%3D%220%2C+10%2C+20%2C+40%22+value%3D%2227%22+%7D%25%0D%0A%25GAUGE%7B+type%3D%22trend%22+name%3D%22t2%22+value%3D%22

<SNIP>

7C+text%2C+40+%7C%22+%7D%25%0D%0A%7C+*Key*+%7C+*Value*+%7C%0D%0A%7C+Name%3A+%7C+John+Smith+%7C%0D%0A%7C+Gender%3A+%7C+M+%25EDITCELL%7Bselect%2C+1%2C+F%2C+M%7D%25+%7C%0D%0A%7C+DOB%3A+%7C+1999%2F12%2F31+%25EDITCELL%7Bdate%2C+10%7D%25+%7C%0D%0A%7C+City%3A+%7C+Chicago+%7C%0D%0A%0D%0A%0D%0A&formtemplate=&topicparent=&cmd=POST /twiki/bin/preview/Sandbox/PaulRyanTest HTTP/1.1" 302 5
192.168.29.35 - - [07/Jul/2004:16:42:21 -0500] "GET /twiki/bin/oops/Sandbox/PaulRyanTest?template=oopsempty HTTP/1.1" 200 1732
192.168.29.35 - - [07/Jul/2004:16:42:21 -0500] "GET /twiki/pub/TWiki/TWikiLogos/twikiRobot46x50.gif HTTP/1.1" 304 -

I'm about 99% sure this is a mod_perl issue. Any and all help is appreciated.

-- PaulRyan - 07 Jul 2004

I have user who is experiencing the URI too long problem when trying to create a new topic. Anyone know what can cause the problem?

-- BenHochstedler - 01 Mar 2007

Please open a new support question.

-- PeterThoeny - 01 Mar 2007