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Revision 1.1 by root, Mon May 26 21:41:32 2008 UTC vs.
Revision 1.6 by root, Fri Oct 24 01:27:29 2008 UTC

1NAME 1NAME
2 AnyEvent::AIO - truly asynchronous file and directrory I/O 2 AnyEvent::HTTP - simple but non-blocking HTTP/HTTPS client
3 3
4SYNOPSIS 4SYNOPSIS
5 use AnyEvent::AIO; 5 use AnyEvent::HTTP;
6 use IO::AIO;
7 6
8 # can now use any of the aio requests your IO::AIO module supports 7 http_get "http://www.nethype.de/", sub { print $_[1] };
9 # as long as you use an event loop supported by AnyEvent. 8
9 # ... do something else here
10 10
11DESCRIPTION 11DESCRIPTION
12 This module is an AnyEvent user, you need to make sure that you use and 12 This module is an AnyEvent user, you need to make sure that you use and
13 run a supported event loop. 13 run a supported event loop.
14 14
15 Loading this module will install the necessary magic to seamlessly 15 This module implements a simple, stateless and non-blocking HTTP client.
16 integrate IO::AIO into AnyEvent, i.e. you no longer need to concern 16 It supports GET, POST and other request methods, cookies and more, all
17 yourself with calling "IO::AIO::poll_cb" or any of that stuff (you still 17 on a very low level. It can follow redirects supports proxies and
18 can, but this module will do it in case you don't). 18 automatically limits the number of connections to the values specified
19 in the RFC.
19 20
20 The AnyEvent watcher can be disabled by executing "undef 21 It should generally be a "good client" that is enough for most HTTP
21 $AnyEvent::AIO::WATCHER". Please notify the author of when and why you 22 tasks. Simple tasks should be simple, but complex tasks should still be
22 think this was necessary. 23 possible as the user retains control over request and response headers.
24
25 The caller is responsible for authentication management, cookies (if the
26 simplistic implementation in this module doesn't suffice), referer and
27 other high-level protocol details for which this module offers only
28 limited support.
29
30 METHODS
31 http_get $url, key => value..., $cb->($data, $headers)
32 Executes an HTTP-GET request. See the http_request function for
33 details on additional parameters and the return value.
34
35 http_head $url, key => value..., $cb->($data, $headers)
36 Executes an HTTP-HEAD request. See the http_request function for
37 details on additional parameters and the return value.
38
39 http_post $url, $body, key => value..., $cb->($data, $headers)
40 Executes an HTTP-POST request with a request body of $body. See the
41 http_request function for details on additional parameters and the
42 return value.
43
44 http_request $method => $url, key => value..., $cb->($data, $headers)
45 Executes a HTTP request of type $method (e.g. "GET", "POST"). The
46 URL must be an absolute http or https URL.
47
48 When called in void context, nothing is returned. In other contexts,
49 "http_request" returns a "cancellation guard" - you have to keep the
50 object at least alive until the callback get called. If the object
51 gets destroyed before the callbakc is called, the request will be
52 cancelled.
53
54 The callback will be called with the response data as first argument
55 (or "undef" if it wasn't available due to errors), and a hash-ref
56 with response headers as second argument.
57
58 All the headers in that hash are lowercased. In addition to the
59 response headers, the "pseudo-headers" "HTTPVersion", "Status" and
60 "Reason" contain the three parts of the HTTP Status-Line of the same
61 name. The pseudo-header "URL" contains the original URL (which can
62 differ from the requested URL when following redirects).
63
64 If the server sends a header multiple times, then their contents
65 will be joined together with a comma (","), as per the HTTP spec.
66
67 If an internal error occurs, such as not being able to resolve a
68 hostname, then $data will be "undef", "$headers->{Status}" will be
69 599 and the "Reason" pseudo-header will contain an error message.
70
71 A typical callback might look like this:
72
73 sub {
74 my ($body, $hdr) = @_;
75
76 if ($hdr->{Status} =~ /^2/) {
77 ... everything should be ok
78 } else {
79 print "error, $hdr->{Status} $hdr->{Reason}\n";
80 }
81 }
82
83 Additional parameters are key-value pairs, and are fully optional.
84 They include:
85
86 recurse => $count (default: $MAX_RECURSE)
87 Whether to recurse requests or not, e.g. on redirects,
88 authentication retries and so on, and how often to do so.
89
90 headers => hashref
91 The request headers to use. Currently, "http_request" may
92 provide its own "Host:", "Content-Length:", "Connection:" and
93 "Cookie:" headers and will provide defaults for "User-Agent:"
94 and "Referer:".
95
96 timeout => $seconds
97 The time-out to use for various stages - each connect attempt
98 will reset the timeout, as will read or write activity. Default
99 timeout is 5 minutes.
100
101 proxy => [$host, $port[, $scheme]] or undef
102 Use the given http proxy for all requests. If not specified,
103 then the default proxy (as specified by $ENV{http_proxy}) is
104 used.
105
106 $scheme must be either missing or "http" for HTTP, or "https"
107 for HTTPS.
108
109 body => $string
110 The request body, usually empty. Will be-sent as-is (future
111 versions of this module might offer more options).
112
113 cookie_jar => $hash_ref
114 Passing this parameter enables (simplified) cookie-processing,
115 loosely based on the original netscape specification.
116
117 The $hash_ref must be an (initially empty) hash reference which
118 will get updated automatically. It is possible to save the
119 cookie_jar to persistent storage with something like JSON or
120 Storable, but this is not recommended, as expire times are
121 currently being ignored.
122
123 Note that this cookie implementation is not of very high
124 quality, nor meant to be complete. If you want complete cookie
125 management you have to do that on your own. "cookie_jar" is
126 meant as a quick fix to get some cookie-using sites working.
127 Cookies are a privacy disaster, do not use them unless required
128 to.
129
130 Example: make a simple HTTP GET request for http://www.nethype.de/
131
132 http_request GET => "http://www.nethype.de/", sub {
133 my ($body, $hdr) = @_;
134 print "$body\n";
135 };
136
137 Example: make a HTTP HEAD request on https://www.google.com/, use a
138 timeout of 30 seconds.
139
140 http_request
141 GET => "https://www.google.com",
142 timeout => 30,
143 sub {
144 my ($body, $hdr) = @_;
145 use Data::Dumper;
146 print Dumper $hdr;
147 }
148 ;
149
150 Example: make another simple HTTP GET request, but immediately try
151 to cancel it.
152
153 my $request = http_request GET => "http://www.nethype.de/", sub {
154 my ($body, $hdr) = @_;
155 print "$body\n";
156 };
157
158 undef $request;
159
160 GLOBAL FUNCTIONS AND VARIABLES
161 AnyEvent::HTTP::set_proxy "proxy-url"
162 Sets the default proxy server to use. The proxy-url must begin with
163 a string of the form "http://host:port" (optionally "https:...").
164
165 $AnyEvent::HTTP::MAX_RECURSE
166 The default value for the "recurse" request parameter (default: 10).
167
168 $AnyEvent::HTTP::USERAGENT
169 The default value for the "User-Agent" header (the default is
170 "Mozilla/5.0 (compatible; AnyEvent::HTTP/$VERSION;
171 +http://software.schmorp.de/pkg/AnyEvent)").
172
173 $AnyEvent::HTTP::MAX_PERSISTENT
174 The maximum number of persistent connections to keep open (default:
175 8).
176
177 Not implemented currently.
178
179 $AnyEvent::HTTP::PERSISTENT_TIMEOUT
180 The maximum time to cache a persistent connection, in seconds
181 (default: 2).
182
183 Not implemented currently.
184
185 $AnyEvent::HTTP::ACTIVE
186 The number of active connections. This is not the number of
187 currently running requests, but the number of currently open and
188 non-idle TCP connections. This number of can be useful for
189 load-leveling.
23 190
24SEE ALSO 191SEE ALSO
25 AnyEvent, Coro::AIO (for a more natural syntax). 192 AnyEvent.
26 193
27AUTHOR 194AUTHOR
28 Marc Lehmann <schmorp@schmorp.de> 195 Marc Lehmann <schmorp@schmorp.de>
29 http://home.schmorp.de/ 196 http://home.schmorp.de/
30 197

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