LWP::RobotUA(3)       User Contributed Perl Documentation      LWP::RobotUA(3)


NAME
       LWP::RobotUA - a class for well-behaved Web robots

SYNOPSIS
         use LWP::RobotUA;
         my $ua = LWP::RobotUA->new('my-robot/0.1', 'me@foo.com');
         $ua->delay(10);  # be very nice -- max one hit every ten minutes!
         ...

         # Then just use it just like a normal LWP::UserAgent:
         my $response = $ua->get('http://whatever.int/...');
         ...

DESCRIPTION
       This class implements a user agent that is suitable for robot
       applications.  Robots should be nice to the servers they visit.  They
       should consult the /robots.txt file to ensure that they are welcomed
       and they should not make requests too frequently.

       But before you consider writing a robot, take a look at
       <http://www.robotstxt.org/>.

       When you use an LWP::RobotUA object as your user agent, then you do not
       really have to think about these things yourself; "robots.txt" files
       are automatically consulted and obeyed, the server isn't queried too
       rapidly, and so on.  Just send requests as you do when you are using a
       normal LWP::UserAgent object (using "$ua->get(...)", "$ua->head(...)",
       "$ua->request(...)", etc.), and this special agent will make sure you
       are nice.

METHODS
       The LWP::RobotUA is a sub-class of LWP::UserAgent and implements the
       same methods. In addition the following methods are provided:

   new
           my $ua = LWP::RobotUA->new( %options )
           my $ua = LWP::RobotUA->new( $agent, $from )
           my $ua = LWP::RobotUA->new( $agent, $from, $rules )

       The LWP::UserAgent options "agent" and "from" are mandatory.  The
       options "delay", "use_sleep" and "rules" initialize attributes private
       to the RobotUA.  If "rules" are not provided, then WWW::RobotRules is
       instantiated providing an internal database of robots.txt.

       It is also possible to just pass the value of "agent", "from" and
       optionally "rules" as plain positional arguments.

   delay
           my $delay = $ua->delay;
           $ua->delay( $minutes );

       Get/set the minimum delay between requests to the same server, in
       minutes.  The default is 1 minute.  Note that this number doesn't have
       to be an integer; for example, this sets the delay to 10 seconds:

           $ua->delay(10/60);

   use_sleep
           my $bool = $ua->use_sleep;
           $ua->use_sleep( $boolean );

       Get/set a value indicating whether the UA should "sleep" in
       LWP::RobotUA if requests arrive too fast, defined as "$ua->delay"
       minutes not passed since last request to the given server.  The default
       is true.  If this value is false then an internal "SERVICE_UNAVAILABLE"
       response will be generated.  It will have a "Retry-After" header that
       indicates when it is OK to send another request to this server.

   rules
           my $rules = $ua->rules;
           $ua->rules( $rules );

       Set/get which WWW::RobotRules object to use.

   no_visits
           my $num = $ua->no_visits( $netloc )

       Returns the number of documents fetched from this server host. Yeah I
       know, this method should probably have been named "num_visits" or
       something like that. :-(

   host_wait
           my $num = $ua->host_wait( $netloc )

       Returns the number of seconds (from now) you must wait before you can
       make a new request to this host.

   as_string
           my $string = $ua->as_string;

       Returns a string that describes the state of the UA.  Mainly useful for
       debugging.

SEE ALSO
       LWP::UserAgent, WWW::RobotRules

COPYRIGHT
       Copyright 1996-2004 Gisle Aas.

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

perl v5.38.0                      2023-09-24                   LWP::RobotUA(3)