=head1 NAME
-Catalyst::Manual::Tutorial::Debugging - Catalyst Tutorial - Part 7: Debugging
+Catalyst::Manual::Tutorial::Debugging - Catalyst Tutorial - Chapter 7: Debugging
=head1 OVERVIEW
-This is B<Part 7 of 10> for the Catalyst tutorial.
+This is B<Chapter 7 of 10> for the Catalyst tutorial.
L<Tutorial Overview|Catalyst::Manual::Tutorial>
=head1 DESCRIPTION
-This part of the tutorial takes a brief look at the primary options
+This chapter of the tutorial takes a brief look at the primary options
available for troubleshooting Catalyst applications.
Note that when it comes to debugging and troubleshooting, there are two
Catalyst is able to easily accommodate both styles of debugging.
+
=head1 LOG STATEMENTS
-Folks in the former group can use Catalyst's C<$c-E<gt>log> facility.
-(See L<Catalyst::Log> for more detail.) For example, if you add the
-following code to a controller action method:
+Folks in the former group can use Catalyst's C<$c-E<gt>log> facility.
+(See L<Catalyst::Log|Catalyst::Log> for more detail.) For example, if
+you add the following code to a controller action method:
$c->log->info("Starting the foreach loop here");
$c->log->debug("Value of \$id is: ".$id);
Then the Catalyst development server will display your message along
-with the other debug output. To accomplish the same thing in a TTSite
-view use:
+with the other debug output. To accomplish the same thing in a TT
+template view use:
+
+ [% c.log.debug("This is a test log message") %]
+
+As with many other logging facilities, you a method is defined for
+each of the following "logging levels" (in increasing order of
+severity/importance):
- [% Catalyst.log.debug("This is a test log message") %]
+ $c->log->debug
+ $c->log->info
+ $c->log->warn
+ $c->log->error
+ $c->log->fatal
You can also use L<Data::Dumper|Data::Dumper> in both Catalyst code
(C<use Data::Dumper; $c-E<gt>log-E<gt>debug("\$var is: ".Dumper($var));)>)
and TT templates (C<[% Dumper.dump(book) %]>.
+
=head1 RUNNING CATALYST UNDER THE PERL DEBUGGER
Members of the interactive-debugger fan club will also be at home with
$ perl -d script/myapp_server.pl
- Loading DB routines from perl5db.pl version 1.27
+ Loading DB routines from perl5db.pl version 1.3
Editor support available.
Enter h or `h h' for help, or `man perldebug' for more help.
- main::(script/myapp_server.pl:14): my $debug = 0;
+ main::(script/myapp_server.pl:16): my $debug = 0;
DB<1>
C<MyApp::Controller::list> method, the console session running the
development server will drop to the Perl debugger prompt:
- MyApp::Controller::Books::list(/home/me/MyApp/script/../lib/MyApp/Controller/Books.pm:40):
- 40: $c->stash->{books} = [$c->model('DB::Books')->all];
+ MyApp::Controller::Books::list(/home/me/MyApp/script/../lib/MyApp/Controller/Books.pm:48):
+ 48: $c->stash->{books} = [$c->model('DB::Books')->all];
DB<1>
DB<1> n
SELECT me.id, me.authors, me.title, me.rating FROM books me:
- MyApp::Controller::Books::list(/home/me/MyApp/script/../lib/MyApp/Controller/Books.pm:44):
- 44: $c->stash->{template} = 'books/list.tt2';
+ MyApp::Controller::Books::list(/home/me/MyApp/script/../lib/MyApp/Controller/Books.pm:53):
+ 53: $c->stash->{template} = 'books/list.tt2';
DB<1>
()
(0+
(bool
- MODIFY_CODE_ATTRIBUTES
- _attr_cache
- _collapse_result
- _construct_object
- _count
- _result_class_accessor
- _result_source_accessor
- all
- carp
+ __source_handle_accessor
+ _add_alias
+ _build_unique_query
+ _calculate_score
+ _collapse_cond
<lines removed for brevity>
DB<2>
mkdir -p lib/Module; cp `perldoc -l Module::Name` lib/Module/
-Note: If you are following along in Ubuntu, you will need to install
+Note: If you are following along in Debian 5, you will need to install
the C<perl-doc> package to use the C<perldoc> command. Use
-C<sudo apt-get install perl-doc> to do that.
+C<sudo aptitude install perl-doc> to do that.
For example, you could make a copy of
L<Catalyst::Plugin::Authentication|Catalyst::Plugin::Authentication>
Check the version of an installed module:
- perl -MModule::Name -e 'print $Module::Name::VERSION;'
+ perl -ME<lt>mod_nameE<gt> -e '"print $E<lt>mod_nameE<gt>::VERSION\n"'
For example:
=back
+=head1 TT DEBUGGING
+
+If you run into issues during the rendering of your template, it might
+be helpful to enable TT C<DEBUG> options. You can do this in a Catalyst
+environment by adding a C<DEBUG> line to the C<__PACKAGE__->config>
+declaration in C<lib/MyApp/View/TT.pm>:
+
+ __PACKAGE__->config({
+ TEMPLATE_EXTENSION => '.tt2',
+ DEBUG => 'undef',
+ });
+
+There are a variety of options you can use, such as 'undef', 'all',
+'service', 'context', 'parser' and 'provider'. See
+L<Template::Constants|Template::Constants> for more information
+(remove the C<DEBUG_> portion of the name shown in the TT docs and
+convert to lower case for use inside Catalyst).
+
+B<NOTE:> B<Please be sure to disable TT debug options before continuing
+with the tutorial> (especially the 'undef' option -- leaving this
+enabled will conflict with several of the conventions used by this
+tutorial to leave some variables undefined on purpose).
+
+
=head1 AUTHOR
Kennedy Clark, C<hkclark@gmail.com>
Please report any errors, issues or suggestions to the author. The
most recent version of the Catalyst Tutorial can be found at
-L<http://dev.catalyst.perl.org/repos/Catalyst/trunk/Catalyst-Manual/lib/Catalyst/Manual/Tutorial/>.
+L<http://dev.catalyst.perl.org/repos/Catalyst/Catalyst-Manual/5.70/trunk/lib/Catalyst/Manual/Tutorial/>.
Copyright 2006-2008, Kennedy Clark, under Creative Commons License
-(L<http://creativecommons.org/licenses/by-nc-sa/2.5/>).
+(L<http://creativecommons.org/licenses/by-sa/3.0/us/>).