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Revision: 1.2
Committed: Thu Jun 5 18:42:16 2008 UTC (16 years 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

# User Rev Content
1 root 1.1 NAME
2 root 1.2 AnyEvent::HTTP - simple but non-blocking HTTP/HTTPS client
3 root 1.1
4     SYNOPSIS
5 root 1.2 use AnyEvent::HTTP;
6 root 1.1
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 root 1.2 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 root 1.1
167     SEE ALSO
168 root 1.2 AnyEvent.
169 root 1.1
170     AUTHOR
171     Marc Lehmann <schmorp@schmorp.de>
172     http://home.schmorp.de/
173