1HTTP::Proxy::HeaderFiltUesre(r3)Contributed Perl DocumenHtTaTtPi:o:nProxy::HeaderFilter(3)
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6 HTTP::Proxy::HeaderFilter - A base class for HTTP message header
7 filters
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10 package MyFilter;
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12 use base qw( HTTP::Proxy::HeaderFilter );
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14 # changes the User-Agent header in all requests
15 # this filter must be pushed on the request stack
16 sub filter {
17 my ( $self, $headers, $message ) = @_;
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19 $message->headers->header( User_Agent => 'MyFilter/1.0' );
20 }
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22 1;
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25 The HTTP::Proxy::HeaderFilter class is used to create filters for HTTP
26 request/response headers.
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28 Creating a HeaderFilter
29 A HeaderFilter is just a derived class that implements some methods
30 called by the proxy. Of all the methods presented below, only
31 "filter()" must be defined in the derived class.
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33 filter()
34 The signature of the filter() method is the following:
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36 sub filter { my ( $self, $headers, $message) = @_; ... }
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38 where $self is the filter object, $headers is a HTTP::Headers
39 object, and $message is either a HTTP::Request or a HTTP::Response
40 object.
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42 The $headers HTTP::Headers object is the one that will be sent to
43 the client (if the filter is on the response stack) or origin
44 server (if the filter is on the request stack). If $headers is
45 modified by the filter, the modified headers will be sent to the
46 client or server.
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48 The init() method (if it exists) is called by the new()
49 constructeur to perform all initisalisation tasks. It's called once
50 in the filter lifetime.
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52 A HTTP::Proxy::HeaderFilter object is a blessed hash, and the base
53 class reserves only hash keys that start with "_hphf".
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55 new()
56 The constructor is defined for all subclasses. Initialisation tasks
57 (if any) for subclasses should be done in the "init()" method (see
58 below).
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60 init()
61 This method is called by the "new()" constructeur to perform all
62 initisalisation tasks. It's called once in the filter lifetime.
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64 It receives all the parameters passed to "new()".
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66 Standard HeaderFilters
67 Standard HTTP::Proxy::HeaderFilter classes are lowercase.
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69 The following HeaderFilters are included in the HTTP::Proxy
70 distribution:
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72 simple
73 This class lets you create a simple header filter from a code
74 reference.
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76 standard
77 This is the filter that provides standard headers handling for
78 HTTP::Proxy. It is loaded automatically by HTTP::Proxy.
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80 Please read each filter's documentation for more details about their
81 use.
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84 Some methods are available to filters, so that they can eventually use
85 the little knowledge they might have of HTTP::Proxy's internals. They
86 mostly are accessors.
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88 proxy()
89 Gets a reference to the HTTP::Proxy objects that owns the filter.
90 This gives access to some of the proxy methods.
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93 Philippe "BooK" Bruhat, <book@cpan.org>.
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96 HTTP::Proxy, HTTP::Proxy::BodyFilter.
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99 Copyright 2003-2005, Philippe Bruhat.
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102 This module is free software; you can redistribute it or modify it
103 under the same terms as Perl itself.
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107perl v5.12.0 2010-05-02 HTTP::Proxy::HeaderFilter(3)