User Help
This chapter is for those needing help using mod_perl and related software.
There is a parallel Getting Help document written mainly for mod_perl core developers, but may be found useful to non-core problems as well.
Whenever you want to report a bug or a problem remember that in order to help you, you need to provide us the information about the software that you are using and other relevant details. Please follow the instructions in the following sections when reporting problems.
The most important thing to understand is that you should try hard to provide all the information that may assist to understand and reproduce the problem. When you prepare a bug report, put yourself in the position of a person who is going to try to help you, realizing that a guess-work on behalf of that helpful person, more often doesn't work than it does. Unfortunately most people don't realize that, and it takes several emails to squeeze the needed details from the person reporting the bug, a process which may drag for days.
First of all:
Apache 2.0 doesn't work with mod_perl 1.0. Apache 1.0 doesn't work with mod_perl 2.0.
So if you aren't using Apache 2.x with mod_perl 2.0 please do not send any bug reports.
META: mod_perl-1.99_xx is mod_perl 2.0 to-be.
Before you post the report, make sure that you've checked the error_log file (t/logs/error_log in case of the failing test suite). Usually the errors are self-descriptive and if you remember to always check this file whenever you have a problem, chances are that you won't need to ask for help.
If you are using an older version than the most recently released one, chances are that a bug that you are about to report has already been fixed. If possible, save us and yourself time and try first to upgrade to the latest version, and only if the bug persists report it.
Reviewing the Changes file may help as well. Here is the Changes file of the most recenly released version: http://perl.apache.org/dist/mod_perl-2.0-current/Changes .
If the problem persists with the latest version, you may also want to try to reproduce the problem with the latest development version. It's possible that the problem was resolved since the last release has been made. Of course if this version solves the problem, don't rush to put it in production unless you know what you are doing. Instead ask the developers when the new version will be released.
Make sure to include a good subject like explaining the problem in a few words. Also please mention that this a problem with mod_perl 2.0 and not mod_perl 1.0. Here is an example of a good subject:
Subject: [mp2] protocol module doesn't work with filters
This is especially important now that we support mod_perl versions 1.0 and 2.0 on the same list.
When sending the bug report, please inline it and don't attach it to the email. It's hard following up on the attachments.
Whenever you send a bug report make sure to include the information about your system by doing the following:
% cd modperl-2.0 % t/REPORT > mybugreport
where modperl-2.0 is the source directory where mod_perl was built. The t/REPORT utility is autogenerated when perl Makefile.PL is run, so you should have it already after building mod_perl.
modperl-2.0
t/REPORT
perl Makefile.PL
META: soon we will have mp2bug report script which will be installed system-wide. For now, if you don't have the source, you can create the report by running the following:
mp2bug
% perl -MApache2 -MApache::TestReportPerl \ -le 'Apache::TestReportPerl->new->run'
Now add the problem description to the report and send it to the list.
If the problem incurs with your own code, please try to reduce the code to the very minimum and include it in the bug report. Remember that if you include a long code, chances that somebody will look at it are low. If the problem is with some CPAN module, just provide its name.
Also remember to include the relevant part of httpd.conf and of startup.pl if applicable. Don't include whole files, only the parts that should aid to understand and reproduce the problem.
Finally don't forget to copy-n-paste (not type!) the relevant part of the error_log file (not the whole file!).
make test
If when running 'make test' some of the tests fail, please re-run them in the verbose mode and post the output of the run and the contents of the error_log file to the list.
For example if 'make test' reports:
Failed Test Stat Wstat Total Fail Failed List of Failed ------------------------------------------------------------------ compat/apache_util.t 15 1 6.67% 13 modperl/pnotes.t 5 1 20% 2
Do the following:
% cd modperl-1.99_xx % make test TEST_VERBOSE=1 \ TEST_FILES="compat/apache_util.t modperl/pnotes.t"
or use an altenative way:
% cd modperl-1.99_xx % rm t/logs/error_log % t/TEST -verbose compat/apache_util.t modperl/pnotes.t
If you are using the latter, remember to remove the error_log file before running tests, so you won't have clutter from the previous run. make test always removes the old error_log file for you.
Also please notice that there is more than one make test run. The first one is running at the top directory, the second inside a sub-directory ModPerl-Registry/. The first logs errors to t/logs/error_log, the second to ModPerl-Registry/t/logs/error_log. Therefore if you get failures in the second run, make sure to chdir() to that directory before you look at the t/logs/error_log file and re-run tests in the verbose mode. For example:
% cd modperl-1.99_xx/ModPerl-Registry % rm t/logs/error_log % t/TEST -verbose closure.t
If during make test or the use of mod_perl you get a segmentation fault you should send to the list a stack backtrace. This section explains how to extract this backtrace.
Of course to generate a useful backtrace you need to have mod_perl with debugging symbols in it (and probably perl and/or httpd too) and also to be able to see the arguments in the calls trace. To accomplish that do:
mod_perl
rebuild mod_perl with MP_DEBUG=1.
MP_DEBUG=1
% perl Makefile.PL MP_DEBUG=1 ... % make && make test && make install
httpd
If the segfault happens inside ap_ or apr_ calls, rebuild httpd with --enable-maintainer-mode:
--enable-maintainer-mode
% ./configure --enable-maintainer-mode ... % make && make install
perl
If the segfault happens inside Perl_ calls, rebuild perl with -Doptimize='-g':
-Doptimize='-g'
% ./Configure -Doptimize='-g' ... % make && make test && make install
3rd party perl modules
if the trace happens in one of the 3rd party perl modules, make sure to rebuild them, now that you've perl re-built with debugging flags. They will automatically pick the right compile flags from perl.
Once a proper stack backtrace is obtained append it to the bug report as explained in the previous section.
If you have general Apache questions, please refer to: http://httpd.apache.org/lists.html.
If you have general Perl questions, please refer to: http://lists.perl.org/.
For other remotely related to mod_perl questions see the references to other documentation.
Finally, if you are not familiar with the modperl list etiquette, please refer to the mod_perl mailing lists' Guidelines before posting.
When developing with mod_perl, you often find yourself having questions regarding other projects and topics like Apache, Perl, SQL, etc. This document will help you find the right resource where you can find the answers to your questions.
Maintainer is the person(s) you should contact with updates, corrections and patches.
Stas Bekman
Only the major authors are listed above. For contributors see the Changes file.
To install mod_perl, copy and paste the appropriate command in to your terminal.
cpanm
cpanm mod_perl
CPAN shell
perl -MCPAN -e shell install mod_perl
For more information on module installation, please visit the detailed CPAN module installation guide.