NAME HTTP::ProxyCheck - a class to check the functionality of HTTP proxy servers. SYNOPSIS use HTTP::ProxyCheck; my $proxy = 'proxy:8080'; my $url = 'http://search.cpan.org/'; my $proxy_check = new HTTP::ProxyCheck( proxy => $proxy, url => $url, answer_size => 'header', print_error => 0, ) or die $HTTP::ProxyCheck::error; print "Trying to connect to '$proxy' and retrieve '$url'\n"; if ( $proxy_check->check() ) { print "'$proxy' returns:\n\n", $proxy_check->get_answer(), "\n\n"; } else { print "Error: ", $proxy_check->get_error(), "\n"; } DESCRIPTION HTTP::ProxyCheck is a class to check HTTP proxy servers. It connects to given HTTP proxy servers and tries to retrieve a provided URL through them. CONSTRUCTOR new( [attribute => $value, ...] ) "new()" is the HTTP::ProxyCheck object constructor. If an error happens while constructing the object, use $HTTP::ProxyCheck::error to get the error message. All named attributes of "new()" are optional. Attributes * proxy => $proxy Specifies the address of the proxy server to check. This can also be done with "set_proxy()". The proxy server address has to match the patter 'host:port'. Host and port are tested whether they are valid. If you want to disable this test, you can set "check_proxy => 0". * check_proxy => 1|0 Set "check_proxy => 0" to disable the check whether the proxy server address is valid. The default value of "check_proxy" is 1 which means, the proxy server address gets tested. This attribute can also be set with "set_check_proxy()". * url => $url Specifies the URL to use for the proxy server check. This can also be done with "set_url()". The URL has to be of a valid form, e.g. 'http://search.cpan.org'. It gets tested whether it is valid. If you want to disable this test, you can set "check_url => 0". * check_url => 1|0 Set "check_url => 0" to disable the check whether the URL is valid. The default value of "check_url" is 1 which means, the URL gets tested. This attribute can also be set with "set_check_url()". * answer_size => short|header|full Defines the size of the proxy server answer. "short" means that only the HTTP status code, e.g. HTTP/1.0 200 OK is returned. With "header" the full HTTP header gets returned, e.g. HTTP/1.0 200 OK Date: Tue, 12 Aug 2003 12:19:46 GMT Server: Apache/1.3.27 (Unix) mod_perl/1.27 Cache-Control: max-age=3600 Expires: Tue, 12 Aug 2003 13:19:46 GMT Last-Modified: Tue, 12 Aug 2003 12:19:46 GMT Content-Type: text/html X-Cache: MISS from search.cpan.org X-Cache: MISS from hactar.earth.net X-Cache-Lookup: HIT from hactar.earth.net:8080 Proxy-Connection: close Use "full" if you want the HTTP header including the whole data from the proxy server. The default value of "answer_size" is "header". This attribute can also be set with "set_answer_size()". * user_agent => $user_agent Specifies the name of the user agent sent to the proxy. If you don't specify a user agent, "HTTP::ProxyCheck/1.3" is used. * verbose_errors => 0|1 Set "verbose_errors => 1" to enable verbose error messages. Verbose error messages look like this: $method failed: $error_message And non-verbose error messages like this: $error_message The default value of "verbose_errors" is 0. For more information see "ERROR HANDLING". * print_error => 1|0 Set "print_error => 0" to disable that error messages are displayed with "Carp::carp()". The default value of "print_error" is 1. For more information see "ERROR HANDLING". * raise_error => 0|1 Set "raise_error => 1" to enable that error messages are displayed with "Carp::croak()" and the program is brought to an end. The default value of "raise_error" is 0. For more information see "ERROR HANDLING". Return values * Okay Blessed reference * Error "undef" The error message can be retrieved with $HTTP::ProxyCheck::error. METHODS check( [attribute => $value, ...] ) "check()" does the actual proxy server checking. It connects to a specified proxy server and tries to get a defined URL through it. All named attributes of "check()" are optional, but "proxy" and "url" must be either set as object or method attribute. Attributes * proxy => $proxy Defines the proxy server to check. "proxy => $proxy" has higher precedence than the object attribute "proxy". It is only used by this method call. It doesn't get saved as object attribute or changes the object attribute. If you want to do this use "set_proxy()". For more information see "CONSTRUCTOR". * check_proxy => 1|0 Set "check_proxy => 0" to disable the check whether the proxy server address is valid. If "check_proxy => 1" is set the proxy server address gets tested. This method attribute has higher precedence than the object attribute "check_proxy". It is only used by this method call. It doesn't get saved as object attribute or changes the object attribute. If you want to do this use "set_check_proxy()". * url => $url Defines the URL to use with the proxy server check. "url => $url" has higher precedence than the object attribute "url". It is only used by this method call. It doesn't get saved as object attribute or changes the object attribute. If you want to do this use "set_url()". For more information see "CONSTRUCTOR". * check_url => 1|0 Set "check_url => 0" to disable the check whether the URL is valid. If "check_url => 1" is set the URL gets tested. This method attribute has higher precedence than the object attribute "check_url". It is only used by this method call. It doesn't get saved as object attribute or changes the object attribute. If you want to do this use "set_check_url()". * answer_size => short|header|full Defines the size of the proxy server answer. This method attribute has higher precedence than the object attribute "answer_size". It is only used by this method call. It doesn't get saved as object attribute or changes the object attribute. If you want to do this use "set_answer_size()". For more information see "CONSTRUCTOR". Return values * Okay 1 The answer of the proxy server can be retrieved with "get_answer()" or $HTTP::ProxyCheck::answer * Error "undef" The error message can be retrieved with "get_error()" or $HTTP::ProxyCheck::error get_answer( ) "get_answer()" gets the most recent proxy server answer. The proxy server answer is in the form specified by the "answer_size" attribute of the HTTP::ProxyCheck object or the "check()" method. For more information see "CONSTRUCTOR". Return values * Okay "$proxy_check->{answer}" This is the most recent proxy server answer. * Error "undef" The error message can be retrieved with "get_error()" or $HTTP::ProxyCheck::error get_error( ) "get_error()" gets the most recent error message. For more information see "ERROR HANDLING". Return values * Okay "$proxy_check->{error}" This is the most recent error message. get_proxy( ) "get_proxy()" gets the current value of the object attribute "proxy". Return values * Okay "$proxy_check->{proxy}" This is the current proxy server address. * Error "undef" The error message can be retrieved with "get_error()" or $HTTP::ProxyCheck::error set_proxy( $proxy ) "set_proxy()" sets the value of the object attribute "proxy". Attributes * $proxy The proxy server address has to match the patter 'host:port'. Host and port are tested whether they are valid. If you want to disable this test, you can set the object attribute "check_proxy => 0" or use set_check_proxy(0). Return values * Okay 1 * Error "undef" The error message can be retrieved with "get_error()" or $HTTP::ProxyCheck::error get_check_proxy( ) "get_check_proxy()" gets the current value of the object attribute "check_proxy". Return values * Okay "$proxy_check->{check_proxy}" This is the current value of the "check_proxy" attribute. set_check_proxy( $check ) "set_check_proxy" sets the object attribute "check_proxy". Attributes * $check Use 0 to disable the check whether the proxy server address is valid and 1 to enable it. Return values * Okay 1 * Error "undef" The error message can be retrieved with "get_error()" or $HTTP::ProxyCheck::error get_url( ) "get_url()" gets the current value of the object attribute "url". Return values * Okay "$proxy_check->{url}" This is the current URL. * Error "undef" The error message can be retrieved with "get_error()" or $HTTP::ProxyCheck::error set_url( $url ) "set_url" sets the object attribute "url". Attributes * $url The URL has to be of a valid form, e.g. 'http://search.cpan.org'. It gets tested whether it is valid. If you want to disable this test, you can set the object attribute "check_url => 0" or use set_check_url(0). Return values * Okay 1 * Error "undef" The error message can be retrieved with "get_error()" or $HTTP::ProxyCheck::error get_check_url( ) "get_check_url()" gets the current value of the object attribute "check_url". Return values * Okay "$proxy_check->{check_url}" This is the current value of the "check_url" attribute. set_check_url( $check ) "set_check_url" sets the object attribute "check_url". Attributes * $check Use 0 to disable the check whether the URL is valid and 1 to enable it. Return values * Okay 1 * Error "undef" The error message can be retrieved with "get_error()" or $HTTP::ProxyCheck::error get_answer_size( ) "get_answer_size()" gets the current value of the object attribute "answer_size". Return values * Okay "$proxy_check->{answer_size}" This is the current answer size. * Error "undef" The error message can be retrieved with "get_error()" or $HTTP::ProxyCheck::error set_answer_size( $answer_size ) "set_answer_size" sets the object attribute "answer_size". Attributes * $answer_size Defines the size of the proxy server answer. Use either "short", "header" or "full" as value. For more information see "CONSTRUCTOR". Return values * Okay 1 * Error "undef" The error message can be retrieved with "get_error()" or $HTTP::ProxyCheck::error ERROR HANDLING HTTP::ProxyCheck has a highly configurable error handling system. It is configured with the attributes "verbose_errors", "print_error" and "raise_error" at object creation: my $proxy_check = new HTTP::ProxyCheck( proxy => 'proxy:8080', url => 'http://search.cpan.org', verbose_errors => 1, print_error => 0, raise_error => 1, ); Every time you call a method of HTTP::ProxyCheck and an error happens, which means the method returns "undef", the error message can be retrieved with "get_error()" or $HTTP::ProxyCheck::error: $proxy_check->set_answer_size( 'full' ) or die $proxy_check->get_error(); $proxy_check->check() or die $HTTP::ProxyCheck::error; If there's an error during the object construction, you can't get the error message through "get_error()". Use $HTTP::ProxyCheck::error instead: my $proxy_check = new HTTP::ProxyCheck( proxy => 'proxy' ) or die $HTTP::ProxyCheck::error; The object attribute "verbose_errors" configures the verbosity of the error message. Set "verbose_errors => 1" to enable verbose error messages and "verbose_errors => 0" to disable verbose error messages. Verbose error messages look like this: $method failed: $error_message And non-verbose error messages like this: $error_message The default value of "verbose_errors" is 0. With "print_error" and "raise_error" you can set the degree of automation of the error handling. If "print_error" is set to 1, the error message is displayed with "Carp::carp()". Set "print_error" to 0 to disable this feature. If "raise_error" is set to 1, the error message is displayed with "Carp::croak()" and the program is brought to an end. If "raise_error" is set to 0, this feature is disabled. The default value of "print_error" is 1 and of "raise_error" it is 0. SUPPORT Contact the "AUTHOR". BUGS Unknown VERSION HTTP::ProxyCheck version 1.2 CHANGES 1.3 Sun May 7 11:51:50 CEST 2006 - Charles Longeau made a small patch to specify the user agent, instead of a fixed "HTTP::ProxyCheck/$VERSION" one. 1.2 Sat May 8 09:38:02 CEST 2004 - Fix to unset the error message of a previous IO::Socket::INET run Thanks to Ben Schnopp 1.1 Tue Aug 12 19:45:00 CEST 2003 - rewrote the module - added better error handling - updated POD 1.0 Fri Feb 21 17:09:32 CET 2003 - gone stable after detailed testing - updated POD (synopsis) 0.2 Fri Feb 21 11:57:43 CET 2003 - added check(answer => $type) - renamed methods to gain more consistency - updated POD (synopsis, methods) 0.1 Wed Feb 5 14:35:25 CET 2003 - original version AUTHOR Thomas Weibel cpan@beeblebrox.net http://beeblebrox.net/ COPYRIGHT Copyright (c) 2004 - 2006 Thomas Weibel. All rights reserved. This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.