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LWP::RobotUA - A class for Web Robots
require LWP::RobotUA; $ua = new LWP::RobotUA 'my-robot/0.1', 'me@foo.com'; $ua->delay(10); # be very nice, go slowly ... # just use it just like a normal LWP::UserAgent $res = $ua->request($req);
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 <URL:http://info.webcrawler.com/mak/projects/robots/robots.html>.
When you use a LWP::RobotUA as your user agent, then you do not really have to think about these things yourself. Just send requests as you do when you are using a normal LWP::UserAgent and this special agent will make sure you are nice.
The LWP::RobotUA is a sub-class of LWP::UserAgent and implements the same methods. In addition the following methods are provided:
Optionally it allows you to specify the WWW::RobotRules object to use.
delay([$minutes])
use_sleep([$boolean])
sleep()
if requests
arrive too fast (before $ua->delay minutes has passed). The default is
TRUE. If this value is FALSE then an internal SERVICE_UNAVAILABLE
response will be generated. It will have an Retry-After header that
indicates when it is OK to send another request to this server.
rules([$rules])
no_visits($netloc)
num_visits()
or
something like that. :-(
host_wait($netloc)
the LWP::UserAgent manpage, the WWW::RobotRules manpage
Copyright 1996-2000 Gisle Aas.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.