oracular (3) Apache::TestTrace.3pm.gz

Provided by: libapache2-mod-perl2_2.0.13-2_amd64 bug

NAME

       Apache::TestTrace - Helper output generation functions

SYNOPSIS

           use Apache::TestTrace;

           debug "foo bar";

           info_sub "missed it";

           error_mark "something is wrong";

           # test sub that exercises all the tracing functions
           sub test {
               print $Apache::TestTrace::LogFH
                     "TraceLevel: $Apache::TestTrace::Level\n";
               $_->($_,[1..3],$_) for qw(emerg alert crit error
                                         warning notice info debug todo);
               print $Apache::TestTrace::LogFH "\n\n"
           };

           # demo the trace subs using default setting
           test();

           {
               # override the default trace level with 'crit'
               local $Apache::TestTrace::Level = 'crit';
               # now only 'crit' and higher levels will do tracing lower level
               test();
           }

           {
               # set the trace level to 'debug'
               local $Apache::TestTrace::Level = 'debug';
               # now only 'debug' and higher levels will do tracing lower level
               test();
           }

           {
               open OUT, ">/tmp/foo" or die $!;
               # override the default Log filehandle
               local $Apache::TestTrace::LogFH = \*OUT;
               # now the traces will go into a new filehandle
               test();
               close OUT;
           }

           # override tracing level via -trace opt
           % t/TEST -trace=debug

           # override tracing level via env var
           % env APACHE_TEST_TRACE_LEVEL=debug t/TEST

DESCRIPTION

       This module exports a number of functions that make it easier generating various diagnostics messages in
       your programs in a consistent way and saves some keystrokes as it handles the new lines and sends the
       messages to STDERR for you.

       This module provides the same trace methods as syslog(3)'s log levels. Listed from low level to high
       level: emerg(), alert(), crit(), error(), warning(), notice(), info(), debug(). The only different
       function is warning(), since warn is already taken by Perl.

       The module provides another trace function called todo() which is useful for todo items. It has the same
       level as debug (the highest).

       There are two more variants of each of these functions. If the _mark suffix is appended (e.g.,
       error_mark) the trace will start with the filename and the line number the function was called from. If
       the _sub suffix is appended (e.g., error_info) the trace will start with the name of the subroutine the
       function was called from.

       If you have "Term::ANSIColor" installed the diagnostic messages will be colorized, otherwise a special
       for each function prefix will be used.

       If "Data::Dumper" is installed and you pass a reference to a variable to any of these functions, the
       variable will be dumped with Data::Dumper::Dumper().

       Functions whose level is above the level set in $Apache::TestTrace::Level become NOPs. For example if the
       level is set to alert, only alert() and emerg() functions will generate the output. The default setting
       of this variable is warning. Other valid values are: emerg, alert, crit, error, warning, notice, info,
       debug.

       Another way to affect the trace level is to set $ENV{APACHE_TEST_TRACE_LEVEL}, which takes effect if
       $Apache::TestTrace::Level is not set. So an explicit setting of $Apache::TestTrace::Level always takes
       precedence.

       By default all the output generated by these functions goes to STDERR. You can override the default
       filehandler by overriding $Apache::TestTrace::LogFH with a new filehandler.

       When you override this package's global variables, think about localizing your local settings, so it
       won't affect other modules using this module in the same run.

TODO

        o provide an option to disable the coloring altogether via some flag
          or import()

AUTHOR

       Stas Bekman with contributions from Doug MacEachern