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Revision: 1.2
Committed: Thu Jun 5 18:42:16 2008 UTC (15 years, 11 months ago) by root
Branch: MAIN
CVS Tags: rel-1_0, rel-1_01
Changes since 1.1: +158 -15 lines
Log Message:
1.0

File Contents

# Content
1 NAME
2 AnyEvent::HTTP - simple but non-blocking HTTP/HTTPS client
3
4 SYNOPSIS
5 use AnyEvent::HTTP;
6
7 DESCRIPTION
8 This module is an AnyEvent user, you need to make sure that you use and
9 run a supported event loop.
10
11 This module implements a simple, stateless and non-blocking HTTP client.
12 It supports GET, POST and other request methods, cookies and more, all
13 on a very low level. It can follow redirects supports proxies and
14 automatically limits the number of connections to the values specified
15 in the RFC.
16
17 It should generally be a "good client" that is enough for most HTTP
18 tasks. Simple tasks should be simple, but complex tasks should still be
19 possible as the user retains control over request and response headers.
20
21 The caller is responsible for authentication management, cookies (if the
22 simplistic implementation in this module doesn't suffice), referer and
23 other high-level protocol details for which this module offers only
24 limited support.
25
26 METHODS
27 http_get $url, key => value..., $cb->($data, $headers)
28 Executes an HTTP-GET request. See the http_request function for
29 details on additional parameters.
30
31 http_head $url, key => value..., $cb->($data, $headers)
32 Executes an HTTP-HEAD request. See the http_request function for
33 details on additional parameters.
34
35 http_post $url, $body, key => value..., $cb->($data, $headers)
36 Executes an HTTP-POST request with a request body of $bod. See the
37 http_request function for details on additional parameters.
38
39 http_request $method => $url, key => value..., $cb->($data, $headers)
40 Executes a HTTP request of type $method (e.g. "GET", "POST"). The
41 URL must be an absolute http or https URL.
42
43 The callback will be called with the response data as first argument
44 (or "undef" if it wasn't available due to errors), and a hash-ref
45 with response headers as second argument.
46
47 All the headers in that hash are lowercased. In addition to the
48 response headers, the three "pseudo-headers" "HTTPVersion", "Status"
49 and "Reason" contain the three parts of the HTTP Status-Line of the
50 same name. If the server sends a header multiple lines, then their
51 contents will be joined together with "\x00".
52
53 If an internal error occurs, such as not being able to resolve a
54 hostname, then $data will be "undef", "$headers->{Status}" will be
55 599 and the "Reason" pseudo-header will contain an error message.
56
57 A typical callback might look like this:
58
59 sub {
60 my ($body, $hdr) = @_;
61
62 if ($hdr->{Status} =~ /^2/) {
63 ... everything should be ok
64 } else {
65 print "error, $hdr->{Status} $hdr->{Reason}\n";
66 }
67 }
68
69 Additional parameters are key-value pairs, and are fully optional.
70 They include:
71
72 recurse => $count (default: $MAX_RECURSE)
73 Whether to recurse requests or not, e.g. on redirects,
74 authentication retries and so on, and how often to do so.
75
76 headers => hashref
77 The request headers to use. Currently, "http_request" may
78 provide its own "Host:", "Content-Length:", "Connection:" and
79 "Cookie:" headers and will provide defaults for "User-Agent:"
80 and "Referer:".
81
82 timeout => $seconds
83 The time-out to use for various stages - each connect attempt
84 will reset the timeout, as will read or write activity. Default
85 timeout is 5 minutes.
86
87 proxy => [$host, $port[, $scheme]] or undef
88 Use the given http proxy for all requests. If not specified,
89 then the default proxy (as specified by $ENV{http_proxy}) is
90 used.
91
92 $scheme must be either missing or "http" for HTTP, or "https"
93 for HTTPS.
94
95 body => $string
96 The request body, usually empty. Will be-sent as-is (future
97 versions of this module might offer more options).
98
99 cookie_jar => $hash_ref
100 Passing this parameter enables (simplified) cookie-processing,
101 loosely based on the original netscape specification.
102
103 The $hash_ref must be an (initially empty) hash reference which
104 will get updated automatically. It is possible to save the
105 cookie_jar to persistent storage with something like JSON or
106 Storable, but this is not recommended, as expire times are
107 currently being ignored.
108
109 Note that this cookie implementation is not of very high
110 quality, nor meant to be complete. If you want complete cookie
111 management you have to do that on your own. "cookie_jar" is
112 meant as a quick fix to get some cookie-using sites working.
113 Cookies are a privacy disaster, do not use them unless required
114 to.
115
116 Example: make a simple HTTP GET request for http://www.nethype.de/
117
118 http_request GET => "http://www.nethype.de/", sub {
119 my ($body, $hdr) = @_;
120 print "$body\n";
121 };
122
123 Example: make a HTTP HEAD request on https://www.google.com/, use a
124 timeout of 30 seconds.
125
126 http_request
127 GET => "https://www.google.com",
128 timeout => 30,
129 sub {
130 my ($body, $hdr) = @_;
131 use Data::Dumper;
132 print Dumper $hdr;
133 }
134 ;
135
136 GLOBAL FUNCTIONS AND VARIABLES
137 AnyEvent::HTTP::set_proxy "proxy-url"
138 Sets the default proxy server to use. The proxy-url must begin with
139 a string of the form "http://host:port" (optionally "https:...").
140
141 $AnyEvent::HTTP::MAX_RECURSE
142 The default value for the "recurse" request parameter (default: 10).
143
144 $AnyEvent::HTTP::USERAGENT
145 The default value for the "User-Agent" header (the default is
146 "Mozilla/5.0 (compatible; AnyEvent::HTTP/$VERSION;
147 +http://software.schmorp.de/pkg/AnyEvent)").
148
149 $AnyEvent::HTTP::MAX_PERSISTENT
150 The maximum number of persistent connections to keep open (default:
151 8).
152
153 Not implemented currently.
154
155 $AnyEvent::HTTP::PERSISTENT_TIMEOUT
156 The maximum time to cache a persistent connection, in seconds
157 (default: 2).
158
159 Not implemented currently.
160
161 $AnyEvent::HTTP::ACTIVE
162 The number of active connections. This is not the number of
163 currently running requests, but the number of currently open and
164 non-idle TCP connections. This number of can be useful for
165 load-leveling.
166
167 SEE ALSO
168 AnyEvent.
169
170 AUTHOR
171 Marc Lehmann <schmorp@schmorp.de>
172 http://home.schmorp.de/
173