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NAME

Log::Any::Adapter::Development -- Manual for developing new Log::Any adapters

VERSION

version 0.09

SYNOPSIS

The adapter module:

   package Log::Any::Adapter::YAL;
   use strict;
   use warnings;
   use Log::Any::Adapter::Util qw(make_method);
   use base qw(Log::Any::Adapter::Base);
   
   # Optionally initialize object
   #
   sub init {
       my ($self) = @_;

       $self->{attr} = ...;
   }
   
   # Create logging methods: debug, info, etc.
   #
   foreach my $method ( Log::Any->logging_methods() ) {
       make_method($method, sub { ... });
   }
   
   # Create detection methods: is_debug, is_info, etc.
   #
   foreach my $method ( Log::Any->detection_methods() ) {
       make_method($method, sub { ... });
   }

and the application:

   Log::Any->set_adapter('YAL');

DESCRIPTION

This document describes how to implement a new Log::Any adapter.

The easiest way to start is to look at the source of existing adapters, such as Log::Any::Adapter::Log4perl and Log::Any::Adapter::Dispatch.

NAMING

If you are going to publicly release your adapter, call it 'Log::Any::Adapter::something' so that users can use it with

    Log::Any->set_adapter(I<something>);

If it's an internal driver, you can call it whatever you like and use it like

    Log::Any->set_adapter('+My::Log::Adapter');

BASE CLASS

All adapters must directly or indirectly inherit from Log::Any::Adapter::Base.

METHODS

Constructor

The constructor (new) is provided by Log::Any::Adapter::Base. It will:

  • place any adapter arguments into a hash, along with the category

  • bless the hash into your subclass

  • call "init" which may be optionally provided by your subclass

At this point, overriding the default constructor is not supported. Hopefully it will not be needed.

The constructor is called whenever a log object is requested. e.g. If the application initializes Log::Any like so:

    Log::Any->set_adapter('Log::YAL', yal_object => $yal, depth => 3);

and then a class requests a logger like so:

    package Foo;
    use Log::Any qw($log);

Then $log will be populated with the return value of:

    Log::Any::Adapter::Yal->new(yal_object => $yal, depth => 3, category => 'Foo');

This is memoized, so if the same category should be requested again (e.g. through a separate get_logger call, the same object will be returned. Therefore, you should try to avoid anything non-deterministic in your "init" function.

Required methods

The following methods have no default implementation, and MUST be defined by your subclass:

debug ($msg)
info ($msg)
notice ($msg)
warning ($msg)
error ($msg)
critical ($msg)
alert ($msg)
emergency ($msg)

These methods log a message at the specified level.

To help generate these methods programmatically, you can get a list of the sub names with #__METHOD

    Log::Any->logging_methods
is_debug ()
is_info ()
is_notice ()
is_warning ()
is_error ()
is_critical ()
is_alert ()
is_emergency ()

These methods return a boolean indicating whether the specified level is active.

To help generate these methods programmatically, you can get a list of the sub names with #__METHOD

    Log::Any->detection_methods

Optional methods

The following methods have no default implementation but MAY be provided by your subclass:

init ()

This is called after the adapter object is created and blessed into your class. It will be a hash containing the parameters that were passed to new(). Perform any necessary validation or initialization here.

Support methods

The following methods are useful for defining adapters:

delegate_method_to_slot ($slot, $method, $adapter_method)

Handle the specified $method by calling $adapter_method on the object contained in $self->{$slot}.

See Log::Any::Adapter::Dispatch and Log::Any::Adapter::Log4perl for examples of usage.

Log::Any->logging_methods

Returns a list of logging methods: debug, info, etc.

Log::Any->detection_methods

Returns a list of detection methods: is_debug, is_info, etc.

Log::Any->logging_and_detection_methods

Returns a combined list of logging and detection methods.

SEE ALSO

Log::Any

COPYRIGHT AND LICENSE

This software is copyright (c) 2011 by Jonathan Swartz.

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