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NAME

Mojar::Log - Simple logger

SYNOPSIS

  use Mojar::Log;

  # Log to STDERR without timestamps
  my $log = Mojar::Log->new(pattern => undef);

  # Customise log file location and timestamp pattern
  my $log = Mojar::Log->new(path => '/tmp/abc.log', pattern => '[%F %X] ');

  # Log messages
  $log->debug('Hmmm?');
  $log->info(q{We're charging per character});
  $log->warn('Uh-oh!');
  $log->error(q{You won't believe this});
  $log->fatal('OH NOES!');

DESCRIPTION

Mojar::Log is a simple logger extending Mojo::Log. The additions are the ability to set defaults at 'use' time (via a mixin) and a more ISO-ish timestamp with support for customising that pattern. (Mojo::Log now let's you customise the format by passing a coderef/closure to the format attribute.)

USAGE

Standard usage is by creating a Log object as in the SYNOPSIS. For shared code, large codebases, or long-running processes, that is the only recommended usage. In standalone classes and scripts it's often more convenient to set the parameters via an implicit mixin. In a standalone script this could be done as:

  use Mojar::Log (
    path => '/var/log/something.log',
    level => 'info',
    pattern => '%F %X...'
  );
  main->log->debug('Go!');

If the same 'use' is employed in a class then it could be done as:

  package MyClass;
  use Mojar::Log (...);

  my $o = MyClass->new(...);
  $o->log->debug('Go!');  # object method
  MyClass->log->debug('Go!');  # class method

Employing use-time parameters entails the implicit creation of a method (mixin) and a hash entry. The mixin works by assigning a Log object to the caller's 'log' hash key, so only works with objects implemented as hashrefs. In other words, only use the convenience of the mixin if that's what you were going to do anyway. [Using the package name to hold a hashref is considered hacky and makes debugging a little trickier; creating a log object per caller object can be considered sub-optimal. If either of those trouble you, please re-read the intro to this section then return to the SYNOPSIS.]

Thanks to Mojolicious being so versatile, you can even use Mojar::Log in those projects, taking advantage of the introduced 'pattern' attribute.

  package MyApp;
  use Mojo::Base 'Mojolicious';
  use Mojar::Log;
  sub startup {
    my $self = shift;
    $self->log(Mojar::Log->new(pattern => '...', path => '...'));
  }

And in a Lite app:

  use Mojolicious::Lite;
  use Mojar::Log;
  app->log(Mojar::Log->new(pattern => '...', path => '...'));

After which you can use the usual Mojolicious 'log' method.

ATTRIBUTES

Mojar::Log inherits its attributes from Mojo::Log and adds the following.

pattern

  $pattern = $log->pattern;
  $log     = $log->pattern('%Y%m%d %H:%M:%S');

Pattern to use for the timestamp. The default pattern (above) is a fairly minimal 17 characters. The timestamp can be disabled altogether by setting it to 'undef'.

  $log->pattern(undef)->info('Timeless!');  # $log then uses no timestamp

See Time::CTime for the full list of specifiers, but a few common choices are the following.

  $log->pattern('[%FT%X] ');  # ISO 8601 timestamp with secs and brackets
  $log->pattern('[%F %R] ');  # ISO 8601 timestamp omitting 'T' and secs
  $log->pattern('%y%m%d%H%M%S');  # A more minimal 12 chars

On a linux system, you can test your pattern by calling date.

  date +'%Y.%m.%d %H.%M.%S'

LEGACY NEEDS

The current version of this requires at least v5 of Mojolicious. If you need to work with an older version of Mojolicious, consider using v1.062.

  cpanm Mojar@1.062

SEE ALSO

Mojo::Log, the parent class which provides the majority of documentation.