# man > TAP::Parser::IteratorFactory

## NAME
    [TAP::Parser::IteratorFactory](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3AIteratorFactory/markdown) - Figures out which SourceHandler objects to use for a given Source

## VERSION
    Version 3.43

## SYNOPSIS
      use [TAP::Parser::IteratorFactory](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3AIteratorFactory/markdown);
      my $factory = [TAP::Parser::IteratorFactory](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3AIteratorFactory/markdown)->new({ %config });
      my $iterator  = $factory->make_iterator( $filename );

## DESCRIPTION
    This is a factory class that takes a [TAP::Parser::Source](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASource/markdown) and runs it through all the registered
    [TAP::Parser::SourceHandlers](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASourceHandlers/markdown) to see which one should handle the source.

    If you're a plugin author, you'll be interested in how to "register_handler"s, how
    "detect_source" works.

## METHODS
### Class Methods
   "new"
    Creates a new factory class:

      my $sf = [TAP::Parser::IteratorFactory](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3AIteratorFactory/markdown)->new( $config );

    $config is optional. If given, sets "config" and calls "load_handlers".

   "register_handler"
    Registers a new [TAP::Parser::SourceHandler](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASourceHandler/markdown) with this factory.

      __PACKAGE__->register_handler( $handler_class );

   "handlers"
    List of handlers that have been registered.

### Instance Methods
   "config"
     my $cfg = $sf->config;
     $sf->config({ Perl => { %config } });

    Chaining getter/setter for the configuration of the available source handlers. This is a hashref
    keyed on handler class whose values contain config to be passed onto the handlers during
    detection & creation. Class names may be fully qualified or abbreviated, eg:

      # these are equivalent
      $sf->config({ '[TAP::Parser::SourceHandler::Perl](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASourceHandler%3A%3APerl/markdown)' => { %config } });
      $sf->config({ 'Perl' => { %config } });

   "load_handlers"
     $sf->load_handlers;

    Loads the handler classes defined in "config". For example, given a config:

      $sf->config({
        MySourceHandler => { some => 'config' },
      });

    "load_handlers" will attempt to load the "MySourceHandler" class by looking in @INC for it in
    this order:

      [TAP::Parser::SourceHandler::MySourceHandler](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASourceHandler%3A%3AMySourceHandler/markdown)
      MySourceHandler

    "croak"s on error.

   "make_iterator"
      my $iterator = $src_factory->make_iterator( $source );

    Given a [TAP::Parser::Source](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASource/markdown), finds the most suitable [TAP::Parser::SourceHandler](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASourceHandler/markdown) to use to create
    a [TAP::Parser::Iterator](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3AIterator/markdown) (see "detect_source"). Dies on error.

   "detect_source"
    Given a [TAP::Parser::Source](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASource/markdown), detects what kind of source it is and returns *one*
    [TAP::Parser::SourceHandler](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASourceHandler/markdown) (the most confident one). Dies on error.

    The detection algorithm works something like this:

      for (@registered_handlers) {
        # ask them how confident they are about handling this source
        $confidence{$handler} = $handler->can_handle( $source )
      }
      # choose the most confident handler

    Ties are handled by choosing the first handler.

## SUBCLASSING
    Please see "SUBCLASSING" in [TAP::Parser](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser/markdown) for a subclassing overview.

### Example
    If we've done things right, you'll probably want to write a new source, rather than sub-classing
    this (see [TAP::Parser::SourceHandler](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASourceHandler/markdown) for that).

    But in case you find the need to...

      package MyIteratorFactory;

      use strict;

      use base '[TAP::Parser::IteratorFactory](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3AIteratorFactory/markdown)';

      # override source detection algorithm
      sub detect_source {
        my ($self, $raw_source_ref, $meta) = @_;
        # do detective work, using $meta and whatever else...
      }

      1;

## AUTHORS
    Steve Purkis

## ATTRIBUTION
    Originally ripped off from [Test::Harness](http://localhost/phpMan.php/perldoc/Test%3A%3AHarness/markdown).

    Moved out of [TAP::Parser](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser/markdown) & converted to a factory class to support extensible TAP source
    detective work by Steve Purkis.

## SEE ALSO
    [TAP::Object](http://localhost/phpMan.php/perldoc/TAP%3A%3AObject/markdown), [TAP::Parser](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser/markdown), [TAP::Parser::SourceHandler](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASourceHandler/markdown), [TAP::Parser::SourceHandler::File](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASourceHandler%3A%3AFile/markdown),
    [TAP::Parser::SourceHandler::Perl](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASourceHandler%3A%3APerl/markdown), [TAP::Parser::SourceHandler::RawTAP](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASourceHandler%3A%3ARawTAP/markdown),
    [TAP::Parser::SourceHandler::Handle](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASourceHandler%3A%3AHandle/markdown), [TAP::Parser::SourceHandler::Executable](http://localhost/phpMan.php/perldoc/TAP%3A%3AParser%3A%3ASourceHandler%3A%3AExecutable/markdown)