One Hat Cyber Team

Edit File: File.pod

=encoding utf8

=head1 NAME

Log::Report::Dispatcher::File - send messages to a file or file-handle

=head1 INHERITANCE

Log::Report::Dispatcher::File
   is a Log::Report::Dispatcher

=head1 SYNOPSIS

dispatcher Log::Report::Dispatcher::File => 'stderr'
   , to => \*STDERR, accept => 'NOTICE-';

# close a dispatcher
 dispatcher close => 'stderr';

# let dispatcher open and close the file
 dispatcher FILE => 'mylog', to => '/var/log/mylog'
   , charset => 'utf-8';
 ...
 dispatcher close => 'mylog';  # will close file

# open yourself, then also close yourself
 open OUT, ">:encoding('iso-8859-1')", '/var/log/mylog'
     or fault "...";
 dispatcher FILE => 'mylog', to => \*OUT;
 ...
 dispatcher close => 'mylog';  
 close OUT;

# dispatch into a scalar
 my $output = '';
 open $outfile, '>', \$output;
 dispatcher FILE => 'into-scalar', to => \$outfile;
 ...
 dispatcher close => 'into-scalar';
 print $output;

=head1 DESCRIPTION

This basic file logger accepts an file-handle or filename as destination.

[1.00] writing to the file protected by a lock, so multiple processes
can write to the same file.

Extends L<"DESCRIPTION" in Log::Report::Dispatcher|Log::Report::Dispatcher/"DESCRIPTION">.
 
=head1 METHODS

Extends L<"METHODS" in Log::Report::Dispatcher|Log::Report::Dispatcher/"METHODS">.
 
=head2 Constructors

Extends L<"Constructors" in Log::Report::Dispatcher|Log::Report::Dispatcher/"Constructors">.
 
=over 4

=item $obj-E<gt>B<close>()

Only when initiated with a FILENAME, the file will be closed.  In any
other case, nothing will be done.

=item Log::Report::Dispatcher::File-E<gt>B<new>($type, $name, %options)

-Option       --Defined in             --Default
  accept         Log::Report::Dispatcher  depend on mode
  charset        Log::Report::Dispatcher  LOCALE
  format                                  <adds timestamp>
  format_reason  Log::Report::Dispatcher  'LOWERCASE'
  locale         Log::Report::Dispatcher  <system locale>
  mode           Log::Report::Dispatcher  'NORMAL'
  replace                                 false
  to                                      <required>

=over 2

=item accept => REASONS

=item charset => CHARSET

=item format => CODE|'LONG'

[1.00] process each printed line.  By default, this adds a timestamp,
but you may want to add hostname, process number, or more.

format => sub { '['.localtime().'] '.$_[0] }
   format => sub { shift }   # no timestamp
   format => 'LONG'

The first parameter to format is the string to print; it is already
translated and trailed by a newline.  The second parameter is the
text-domain (if known).

[1.10] As third parameter, you get the $msg raw object as well (maybe
you want to use the message context?)
[1.19] After the three positional parameters, there may be a list
of pairs providing additional facts about the exception.  It may
contain C<location> information.

The "LONG" format is equivalent to:

my $t = strftime "%FT%T", gmtime;
  "[$t $$] $_[1] $_[0]"

Use of context:

format => sub { my ($msgstr, $domain, $msg, %more) = @_;
      my $host = $msg->context->{host};
      "$host $msgstr";
   }

=item format_reason => 'UPPERCASE'|'LOWERCASE'|'UCFIRST'|'IGNORE'|CODE

=item locale => LOCALE

=item mode => 'NORMAL'|'VERBOSE'|'ASSERT'|'DEBUG'|0..3

=item replace => BOOLEAN

Only used in combination with a FILENAME: throw away the old file
if it exists.  Probably you wish to append to existing information.

Use the LOCALE setting by default, which is LC_CTYPE or LC_ALL or LANG
(in that order).  If these contain a character-set which Perl understands,
then that is used, otherwise silently ignored.

=item to => FILENAME|FILEHANDLE|OBJECT|CODE

You can either specify a FILENAME, which is opened in append mode with
autoflush on. Or pass any kind of FILE-HANDLE or some OBJECT which
implements a C<print()> method. You probably want to have autoflush
enabled on your FILE-HANDLES.

When cleaning-up the dispatcher, the file will only be closed in case
of a FILENAME.

[1.10] When you pass a CODE, then for each log message the function is
called with two arguments: this dispatcher object and the message object.
In some way (maybe via the message context) you have to determine the
log filename.  This means that probably many log-files are open at the
same time.

# configuration time
   dispatcher FILE => 'logfile', to =>
       sub { my ($disp, $msg) = @_; $msg->context->{logfile} };

# whenever you want to change the logfile
   textdomain->updateContext(logfile => '/var/log/app');
   (textdomain 'mydomain')->setContext(logfile => '/var/log/app');

# or
   error __x"help", _context => {logfile => '/dev/tty'};
   error __x"help", _context => "logfile=/dev/tty";

=back

=head2 Accessors

Extends L<"Accessors" in Log::Report::Dispatcher|Log::Report::Dispatcher/"Accessors">.
 
=over 4

=item $obj-E<gt>B<filename>()

Returns the name of the opened file, or C<undef> in case this dispatcher
was started from a file-handle or file-object.

=item $obj-E<gt>B<format>()

=item $obj-E<gt>B<isDisabled>()

Inherited, see L<Log::Report::Dispatcher/"Accessors">

=item $obj-E<gt>B<mode>()

Inherited, see L<Log::Report::Dispatcher/"Accessors">

=item $obj-E<gt>B<name>()

Inherited, see L<Log::Report::Dispatcher/"Accessors">

=item $obj-E<gt>B<needs>( [$reason] )

Inherited, see L<Log::Report::Dispatcher/"Accessors">

=item $obj-E<gt>B<output>($msg)

Returns the file-handle to write the log lines to. [1.10] This may
depend on the $msg (especially message context)

=item $obj-E<gt>B<type>()

Inherited, see L<Log::Report::Dispatcher/"Accessors">

=back

=head2 File maintenance

=over 4

=item $obj-E<gt>B<rotate>($filename|CODE)

[1.00] Move the current file to $filename, and start a new file.

=back

=head2 Logging

Extends L<"Logging" in Log::Report::Dispatcher|Log::Report::Dispatcher/"Logging">.
 
=over 4

=item $obj-E<gt>B<addSkipStack>(@CODE)

=item Log::Report::Dispatcher::File-E<gt>B<addSkipStack>(@CODE)