/ 
Log-ger-0.004
River stage four • 573 direct dependents • 1483 total dependents
/ Log::ger

NAME

Log::ger - A lightweight, flexible logging framework

VERSION

version 0.004

SYNOPSIS

In your module (producer):

package Foo;
use Log::ger; # will import some logging methods e.g. log_warn, log_error

# produce some logs
sub foo {
    ...
    log_warn "an error occurred";
    log_error "an error occurred: %03d - %s", $errcode, $errmsg;
}
1;

In your application:

use Foo;
use Log::ger::Output 'Screen';

foo();

DESCRIPTION

EARLY RELEASE, EXPERIMENTAL.

This is yet another logging framework. Like Log::Any, it separates producers and consumers. Unlike Log::Any (and like Log::Contextual), it uses plain functions (non-OO). Some features:

  • Low startup overhead;

  • Low overhead;

  • Customizable levels;

  • Changing levels and outputs during run-time;

    For example, you can debug your running server application to turn on trace logs temporarily when you need to investigate something.

  • Option to optimize away the logging statements when unnecessary;

    See Log::ger::OptAway.

  • Interoperability with other logging frameworks;

    See Log::ger::Output::LogAny to interop with Log::Any.

FAQ

How do I create multiple loggers?

For example, in Log::Any:

my $log = Log::Any->get_logger;
my $log_dump = Log::Any->get_logger(category => "dump"); # to dump contents

$log->debugf("Headers is: %s", $http_res->{headers});
$log_dump->debug($http_res->{content});

in Log::ger:

# instead of installing to package, we setup objects/hashes for the secondary
# loggers
my $log_dump = Log::ger::setup_object(category => "dump");
# or, for hash: my $log_dump = Log::ger::setup_hash(category => "dump");

log_debug("Headers is: %s", $http_res->{headers});
$log_dump->log_debug($http_res->{content});
# or, for hash: $log_dump->{log_debug}->($http_res->{content});

How do I do custom formatting

For example, a la Log::Contextual:

log_warn { 'The number of stuffs is: ' . $obj->stuffs_count };

See Log::ger::Format::Block for an example.

INTERNALS

Plugins

Plugins are how Log::ger provides its flexibility. Plugins are run at various phases. Plugin routine is passed a hash argument and is expected to return an array:

[$result, $flow_control]

Some phases will stop after the first plugin that returns non-undef $result. $flow_control can be set to 1 to stop immediately after this hook.

Aguments received by plugin: target (str, can be package if installing to a package, or hash or object), target_arg (str, when target is package, will be the package name; when target is hash will be the hash; when target is object will be the object's package), setup_args (hash, arguments passed to Log::ger when importing). These arguments are received by plugins for create_log_routine and create_log_is_routine which are run for every level: level (numeric level), str_level.

Available phases:

  • create_filter_routine

  • create_formatter_routine

  • create_log_routine phase

    Used to create "log_level" routines. Run for each level.

  • create_log_is_routine phase

    Used to create "log_level" routines. Run for each level.

  • after_install_log_routine phase

SEE ALSO

Some other recommended logging frameworks: Log::Any, Log::Contextual.

AUTHOR

perlancar <perlancar@cpan.org>

COPYRIGHT AND LICENSE

This software is copyright (c) 2017 by perlancar@cpan.org.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.