问题
I have the same question as was asked HERE but unfortunately I cannot install Moose and I think the solution described there was particular to Moose. Can someone tell me how to the same in old school "use base" speak?
To reiterate the question, I would like to have my base classes to have an automatic logging mechanism using Log4perl so if the user does not do anything I get some reasonable logging but if the user of my class needs/wants to overwrite the logger they can.
回答1:
Well, if you want to have role/mixin type behavior and such just like in the other answer, you could use vanilla multiple inheritance, or better yet use something like Ovid's Role::Basic.
回答2:
Here is the solution I came up with for anyone else that might be interested:
MyBaseClass.pm
package MyBaseClass;
use Log::Log4perl;
use Log::Log4perl::Layout;
use Log::Log4perl::Level;
our $VERSION = '0.01';
sub new {
my $class = shift;
my $name = shift;
my $starttime = time;
my $self = {
NAME => $name, # Single-word name (use underscores)
STDOUTLVL => "INFO",
LOGOUTLVL => "WARN",
LOG => ""
};
bless($self, $class);
return $self;
}
sub init_logs {
my ( $self, $stdoutlvl, $logoutlvl, $no_color, $trace_stack ) = @_;
# If stdoutlvl was not supplied then default to "INFO"
$self->{STDOUTLVL} = ( defined $stdoutlvl ) ? $stdoutlvl : "INFO";
$self->{LOGOUTLVL} = ( defined $logoutlvl ) ? $logoutlvl : "WARN";
my $color_enabled = ( defined $no_color ) ? "" : "ColoredLevels";
# Define a category logger
$self->{LOG} = Log::Log4perl->get_logger("MyBaseClass");
# Define 3 appenders, one for screen, one for script log and one for baseclass logging.
my $stdout_appender = Log::Log4perl::Appender->new(
"Log::Log4perl::Appender::Screen$color_enabled",
name => "screenlog",
stderr => 0);
my $script_appender = Log::Log4perl::Appender->new(
"Log::Log4perl::Appender::File",
name => "scriptlog",
filename => "/tmp/$self->{NAME}.log");
my $mybaseclass_appender = Log::Log4perl::Appender->new(
"Log::Log4perl::Appender::File",
name => "mybaseclasslog",
filename => "/tmp/MyBaseClass.pm.log");
# Define a layouts
my $stdout_layout;
if ( defined $trace_stack ) {
$stdout_layout = Log::Log4perl::Layout::PatternLayout->new("[%-5p] %M-%L --- %m --- %T%n");
} else {
$stdout_layout = Log::Log4perl::Layout::PatternLayout->new("[%-5p] %M-%L --- %m ---%n");
}
my $file_layout = Log::Log4perl::Layout::PatternLayout->new("%d [%-5p] PID_%05P $ENV{USER} --- %m --- %l %T%n");
my $mybaseclass_layout = Log::Log4perl::Layout::PatternLayout->new("%d [%-5p] PID_%05P $ENV{USER} --- %m --- %l %rmS %T%n");
# Assign the appenders to there layouts
$stdout_appender->layout($stdout_layout);
$script_appender->layout($file_layout);
$mybaseclass_appender->layout($mybaseclass_layout);
# Set the log levels and thresholds
$self->{LOG}->level($self->{STDOUTLVL});
$script_appender->threshold($self->{LOGOUTLVL});
$mybaseclass_appender->threshold("WARN"); # For the mybaseclass log I only ever want to read about WARNs or above:
# Add the appenders to the log object
$self->{LOG}->add_appender($stdout_appender);
$self->{LOG}->add_appender($script_appender);
$self->{LOG}->add_appender($mybaseclass_appender);
return( $self->{LOG} );
}
...
1;
MyRegrClass.pm
package MyBaseClass::MyRegrClass;
# This class extends from the base class MyBaseClass
use base qw(MyBaseClass);
sub new {
my $class = shift;
my $self = $class->SUPER::new( @_ );
...
$self->{passed} = 0;
bless($self, $class);
return $self;
}
...
1;
my_script.pl
#!/usr/bin/perl -w
use Getopt::Long;
use MyBaseClass::MyRegrClass;
##################################
# Initialize global variables
##################################
my $VERSION = '0.02';
my $regr_obj = MyBaseClass::MyRegrClass->new("my_script.pl");
##################################
# DEFINE ARGUMENTS TO BE PASSED IN
##################################
my %opts = ();
print_header("FATAL") unless &GetOptions(\%opts, 'help',
'min_stdout_lvl=s',
'min_logout_lvl=s',
'no_color'
);
if ( exists $opts{help} ) {
print_header();
exit;
}
##################################
# CONFIGURE OPTIONS
##################################
$opts{min_stdout_lvl} = "INFO" unless exists $opts{min_stdout_lvl};
$opts{min_logout_lvl} = "WARN" unless exists $opts{min_logout_lvl};
my $log = $regr_obj->init_logs($opts{min_stdout_lvl},$opts{min_logout_lvl},$opts{no_color});
$log->info("Only printed to STDOUT.");
$log->warn("Gets printed to the two logs and STDOUT.");
...
回答3:
Sounds a bit like Log::Any.
来源:https://stackoverflow.com/questions/5267486/self-logging-perl-modules-without-moose