.\" -*- mode: troff; coding: utf-8 -*- .\" Automatically generated by Pod::Man 5.01 (Pod::Simple 3.43) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" \*(C` and \*(C' are quotes in nroff, nothing in troff, for use with C<>. .ie n \{\ . ds C` "" . ds C' "" 'br\} .el\{\ . ds C` . ds C' 'br\} .\" .\" Escape single quotes in literal strings from groff's Unicode transform. .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" .\" If the F register is >0, we'll generate index entries on stderr for .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index .\" entries marked with X<> in POD. Of course, you'll have to process the .\" output yourself in some meaningful fashion. .\" .\" Avoid warning from groff about undefined register 'F'. .de IX .. .nr rF 0 .if \n(.g .if rF .nr rF 1 .if (\n(rF:(\n(.g==0)) \{\ . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF .\" ======================================================================== .\" .IX Title "LWP::RobotUA 3pm" .TH LWP::RobotUA 3pm 2024-03-16 "perl v5.38.2" "User Contributed Perl Documentation" .\" For nroff, turn off justification. Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH NAME LWP::RobotUA \- a class for well\-behaved Web robots .SH SYNOPSIS .IX Header "SYNOPSIS" .Vb 4 \& use LWP::RobotUA; \& my $ua = LWP::RobotUA\->new(\*(Aqmy\-robot/0.1\*(Aq, \*(Aqme@foo.com\*(Aq); \& $ua\->delay(10); # be very nice \-\- max one hit every ten minutes! \& ... \& \& # Then just use it just like a normal LWP::UserAgent: \& my $response = $ua\->get(\*(Aqhttp://whatever.int/...\*(Aq); \& ... .Ve .SH DESCRIPTION .IX Header "DESCRIPTION" This class implements a user agent that is suitable for robot applications. Robots should be nice to the servers they visit. They should consult the \fI/robots.txt\fR file to ensure that they are welcomed and they should not make requests too frequently. .PP But before you consider writing a robot, take a look at . .PP When you use an \fILWP::RobotUA\fR object as your user agent, then you do not really have to think about these things yourself; \f(CW\*(C`robots.txt\*(C'\fR files are automatically consulted and obeyed, the server isn't queried too rapidly, and so on. Just send requests as you do when you are using a normal \fILWP::UserAgent\fR object (using \f(CW\*(C`$ua\->get(...)\*(C'\fR, \f(CW\*(C`$ua\->head(...)\*(C'\fR, \&\f(CW\*(C`$ua\->request(...)\*(C'\fR, etc.), and this special agent will make sure you are nice. .SH METHODS .IX Header "METHODS" The LWP::RobotUA is a sub-class of LWP::UserAgent and implements the same methods. In addition the following methods are provided: .SS new .IX Subsection "new" .Vb 3 \& my $ua = LWP::RobotUA\->new( %options ) \& my $ua = LWP::RobotUA\->new( $agent, $from ) \& my $ua = LWP::RobotUA\->new( $agent, $from, $rules ) .Ve .PP The LWP::UserAgent options \f(CW\*(C`agent\*(C'\fR and \f(CW\*(C`from\*(C'\fR are mandatory. The options \f(CW\*(C`delay\*(C'\fR, \f(CW\*(C`use_sleep\*(C'\fR and \f(CW\*(C`rules\*(C'\fR initialize attributes private to the RobotUA. If \f(CW\*(C`rules\*(C'\fR are not provided, then WWW::RobotRules is instantiated providing an internal database of \&\fIrobots.txt\fR. .PP It is also possible to just pass the value of \f(CW\*(C`agent\*(C'\fR, \f(CW\*(C`from\*(C'\fR and optionally \f(CW\*(C`rules\*(C'\fR as plain positional arguments. .SS delay .IX Subsection "delay" .Vb 2 \& my $delay = $ua\->delay; \& $ua\->delay( $minutes ); .Ve .PP Get/set the minimum delay between requests to the same server, in \&\fIminutes\fR. The default is \f(CW1\fR minute. Note that this number doesn't have to be an integer; for example, this sets the delay to \f(CW10\fR seconds: .PP .Vb 1 \& $ua\->delay(10/60); .Ve .SS use_sleep .IX Subsection "use_sleep" .Vb 2 \& my $bool = $ua\->use_sleep; \& $ua\->use_sleep( $boolean ); .Ve .PP Get/set a value indicating whether the UA should "sleep" in LWP::RobotUA if requests arrive too fast, defined as \f(CW\*(C`$ua\->delay\*(C'\fR minutes not passed since last request to the given server. The default is true. If this value is false then an internal \f(CW\*(C`SERVICE_UNAVAILABLE\*(C'\fR response will be generated. It will have a \f(CW\*(C`Retry\-After\*(C'\fR header that indicates when it is OK to send another request to this server. .SS rules .IX Subsection "rules" .Vb 2 \& my $rules = $ua\->rules; \& $ua\->rules( $rules ); .Ve .PP Set/get which \fIWWW::RobotRules\fR object to use. .SS no_visits .IX Subsection "no_visits" .Vb 1 \& my $num = $ua\->no_visits( $netloc ) .Ve .PP Returns the number of documents fetched from this server host. Yeah I know, this method should probably have been named \f(CW\*(C`num_visits\*(C'\fR or something like that. :\-( .SS host_wait .IX Subsection "host_wait" .Vb 1 \& my $num = $ua\->host_wait( $netloc ) .Ve .PP Returns the number of \fIseconds\fR (from now) you must wait before you can make a new request to this host. .SS as_string .IX Subsection "as_string" .Vb 1 \& my $string = $ua\->as_string; .Ve .PP Returns a string that describes the state of the UA. Mainly useful for debugging. .SH "SEE ALSO" .IX Header "SEE ALSO" LWP::UserAgent, WWW::RobotRules .SH COPYRIGHT .IX Header "COPYRIGHT" Copyright 1996\-2004 Gisle Aas. .PP This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.