Ryo Anazawa
and 1 contributors

NAME

WWW::GoKGS - KGS Go Server (http://www.gokgs.com/) Scraper

SYNOPSIS

  use WWW::GoKGS;

  my $gokgs = WWW::GoKGS->new(
      from => 'user@example.com'
  );

  # Game archives
  my $game_archives_1 = $gokgs->scrape( '/gameArchives.jsp?user=foo' );
  my $game_archives_2 = $gokgs->game_archives->query( user => 'foo' );

  # Top 100 players
  my $top_100_1 = $gokgs->scrape( '/top100.jsp' );
  my $top_100_2 = $gokgs->top_100->query;

  # List of tournaments 
  my $tourn_list_1 = $gokgs->scrape( '/tournList.jsp?year=2014' );
  my $tourn_list_2 = $gokgs->tourn_list->query( year => 2014 );

  # Information for the tournament
  my $tourn_info_1 = $gokgs->scrape( '/tournInfo.jsp?id=123' );
  my $tourn_info_2 = $gokgs->tourn_info->query( id => 123 );

  # The tournament entrants
  my $tourn_entrants_1 = $gokgs->scrape( '/tournEntrans.jsp?id=123&sort=n' );
  my $tourn_entrants_2 = $gokgs->tourn_entrants->query( id => 123, sort => 'n' );

  # The tournament games
  my $tourn_games_1 = $gokgs->scrape( '/tournGames.jsp?id=123&round=1' );
  my $tourn_games_2 = $gokgs->tourn_games->query( id => 123, round => 1 );

  # List of time zones
  my $tz_list_1 = $gokgs->scrape( '/tzList.jsp' );
  my $tz_list_2 = $gokgs->tz_list->query;

DESCRIPTION

This module is a KGS Go Server (http://www.gokgs.com/) scraper. KGS allows the users to play a board game called go a.k.a. baduk (Korean) or weiqi (Chinese). Although the web server provides resources generated dynamically, such as Game Archives, they are formatted as HTML, the only format. This module provides yet another representation of those resources, Perl data structure.

This class maps a URI preceded by http://www.gokgs.com/ to a proper scraper. The supported resources on KGS are as follows:

KGS Game Archives (http://www.gokgs.com/archives.jsp)

Handled by WWW::GoKGS::Scraper::GameArchives.

Top 100 KGS Players (http://www.gokgs.com/top100.jsp)

Handled by WWW::GoKGS::Scraper::Top100.

KGS Tournaments (http://www.gokgs.com/tournList.jsp)

Handled by WWW::GoKGS::Scraper::TournList, WWW::GoKGS::Scraper::TournInfo, WWW::GoKGS::Scraper::TournEntrants and WWW::GoKGS::Scraper::TournGames.

KGS Time Zone Selector (http://www.gokgs.com/tzList.jsp)

Handled by WWW::GoKGS::Scraper::TzList.

ATTRIBUTES

$UserAgent = $gokgs->user_agent
$gokgs->user_agent( LWP::RoboUA->new(...) )

Can be used to get or set a user agent object which is used to GET the requested resource. Defaults to LWP::RobotUA object which consults http://www.gokgs.com/robots.txt before sending HTTP requests, and also sets a proper delay between requests.

NOTE: LWP::RobotUA fails to read /robots.txt since the KGS web server doesn't returns the Content-Type response header as of June 23rd, 2014. This module can not solve this problem.

You can also set your own user agent object which inherits from LWP::UserAgent as follows:

  use LWP::UserAgent;

  $gokgs->user_agent(
      LWP::UserAgent->new(
          agent => 'MyAgent/1.00'
      )
  );

NOTE: You should set a delay between requests to avoid overloading the KGS server.

$GameArchives = $gokgs->game_archives

Returns a WWW::GoKGS::Scraper::GameArchives object.

$Top100 = $gokgs->top_100

Returns to a WWW::GoKGS::Scraper::Top100 object.

$TournList = $gokgs->tourn_list

Returns a WWW::GoKGS::Scraper::TournList object.

$TournInfo = $gokgs->tourn_info

Returns a WWW::GoKGS::Scraper::TournInfo object.

$TournEntrants = $gokgs->tourn_entrants

Returns a WWW::GoKGS::Scraper::TournEntrants object.

$TournGames = $gokgs->tourn_games

Returns a WWW::GoKGS::Scraper::TournGames object.

$TzList = $gokgs->tz_list

Returns a WWW::GoKGS::Scraper::TzList object.

INSTANCE METHODS

$email_address = $gokgs->from
$gokgs->from( 'user@example.com' )

Can be used to get or set your email address which is used to send the From request header that indicates who is making the request.

$agent = $gokgs->agent
$gokgs->agent( 'MyAgent/0.01' )

Can be used to get or set the product token that is used to send the User-Agent request header.

$Response = $gokgs->get( URI->new(...) )

A shortcut for:

  my $response = $gokgs->user_agent->get( URI->new(...) );

This method is used by scrape method to GET the requested resource. You can override this method by subclassing.

$cookie_jar = $gokgs->cookie_jar
$gokgs->cookie_jar( $cookie_jar_obj )

Can be used to get or set a cookie jar object to use.

$scraper = $gokgs->can_scrape( '/fooBar.jsp' )
$scraper = $gokgs->can_scrape( 'http://www.gokgs.com/fooBar.jsp' )

Returns a scraper object which can scrape the resource specified by the given URL. If the scraper object does not exist, then undef is returned. This method can be used to check whether $gokgs can scrape the resource.

$HashRef = $gokgs->scrape( '/gameArchives.jsp?user=foo' )
$HashRef = $gokgs->scrape( 'http://www.gokgs.com/gameArchives.jsp?user=foo' )

A shortcut for:

  my $uri = URI->new( 'http://www.gokgs.com/gameArchives.jsp?user=foo' );
  my $game_archives = $gokgs->game_archives->scrape( $uri );

See WWW::GoKGS::Scraper::GameArchives for details.

$HashRef = $gokgs->scrape( '/top100.jsp' )
$HashRef = $gokgs->scrape( 'http://www.gokgs.com/top100.jsp' )

A shortcut for:

  my $uri = URI->new( 'http://www.gokgs.com/top100.jsp' );
  my $top_100 = $gokgs->top_100->scrape( $uri );

See WWW::GoKGS::Scraper::Top100 for details.

$HashRef = $gokgs->scrape( '/tournList.jsp?year=2014' )
$HashRef = $gokgs->scrape( 'http://www.gokgs.com/tournList.jsp?year=2014' )

A shortcut for:

  my $uri = URI->new( 'http://www.gokgs.com/tournList.jsp?year=2014' );
  my $tourn_list = $gokgs->tourn_list->scrape( $uri );

See WWW::GoKGS::Scraper::TournList for details.

$HashRef = $gokgs->scrape( '/tournInfo.jsp?id=123' )
$HashRef = $gokgs->scrape( 'http://www.gokgs.com/tournInfo.jsp?id=123' )

A shortcut for:

  my $uri = URI->new( 'http://www.gokgs.com/tournInfo.jsp?id=123' );
  my $tourn_info = $gokgs->tourn_info->scrape( $uri );

See WWW::GoKGS::Scraper::TournInfo for details.

$HashRef = $gokgs->scrape( '/tournEntrants.jsp?id=123&s=n' )
$HashRef = $gokgs->scrape( 'http://www.gokgs.com/tournEntrants.jsp?id=123&s=n' )

A shortcut for:

  my $uri = URI->new( 'http://www.gokgs.com/tournEntrants.jsp?id=123&s=n' );
  my $tourn_entrants = $gokgs->tourn_entrants->scrape( $uri );

See WWW::GoKGS::Scraper::TournEntrants for details.

$HashRef = $gokgs->scrape( '/tournGames.jsp?id=123&round=1' )
$HashRef = $gokgs->scrape( 'http://www.gokgs.com/tournGames.jsp?id=123&round=1' )

A shortcut for:

  my $uri = URI->new( 'http://www.gokgs.com/tournGames.jsp?id=123&round=1' );
  my $tourn_games = $gokgs->tourn_games->scrape( $uri );

See WWW::GoKGS::Scraper::TournGames for details.

$HashRef = $gokgs->scrape( '/tzList.jsp' )
$HashRef = $gokgs->scrape( 'http://www.gokgs.com/tzList.jsp' )

A shortcut for:

  my $uri = URI->new( 'http://www.gokgs.com/tzList.jsp' );
  my $tz_list = $gokgs->tz_list->scrape( $uri );

See WWW::GoKGS::Scraper::TzList for details.

$scraper = $gokgs->get_scraper( $path )

Returns a scraper object which can scrape a resource located at $path on KGS. If the scraper object does not exist, then undef is returned.

  my $game_archives = $gokgs->get_scraper( '/gameArchives.jsp' );
  # => WWW::GoKGS::Scraper::GameArchives object
$gokgs->each_scraper( sub { my ($path, $scraper) = @_; ... } )

Given a subref, applies the subroutine to each scraper object in turn. The callback routine is called with two parameters; the path to the resource on KGS and the scraper object which can scrape the resource.

  $gokgs->each_scraper(sub {
      my $path = shift; # => "/gameArchives.jsp"
      my $scraper = shift; # isa WWW::GoKGS::Scraper::GameArchives

      # overwrite "user_agent" attributes of all the scraper objects
      $scraper->user_agent( $gokgs->user_agent );
  });

DIAGNOSTICS

This module throws the following exceptions:

LWP::RobotUA from required

This message is printed by the constructor of LWP::RobotUA. You must provide your email address when you use the module.

  my $gokgs = WWW::GoKGS->new(
      from => 'user@example.com'
  );
Don't know how to scrape '/fooBar.jsp'

You tried to scrape a resource which $gokgs can't handle. Use can_scrape before invoke the scrape method.

  # scrape safely
  if ( $gokgs->can_scrape('/fooBar.jsp') ) {
      my $result = $gokgs->scrape('/fooBar.jsp');
  }
GET /fooBar.jsp failed: ...

$gokgs failed to GET the requested resource. The reason phrase is added to the end of the message.

LIMITATIONS

Although KGS website allows you to set a locale and time zone by using HTTP cookie, this module ignores the settings. The scrapers assume the locale is set to en_US, and the time zone GMT.

  # not supported
  $gokgs->user_agent->cookie_jar(...);

ENVIRONMENTAL VARIABLES

AUTHOR_TESTING

Some tests for scrapers send HTTP requests to GET resources on KGS. When you run ./Build test, they are skipped by default to avoid overloading the KGS server. To run those tests, you have to set AUTHOR_TESTING to true explicitly:

  $ perl Build.PL
  $ env AUTHOR_TESTING=1 ./Build test

Author tests are run by Travis CI once a day. You can visit the website to check whether the tests passed or not.

ACKNOWLEDGEMENT

Thanks to wms, the author of KGS Go Server, we can enjoy playing go online for free.

SEE ALSO

KGS Go Server, Web::Scraper

AUTHOR

Ryo Anazawa (anazawa@cpan.org)

LICENSE

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic.