1Net::HTTP(3) User Contributed Perl Documentation Net::HTTP(3)
2
6 Net::HTTP - Low-level HTTP connection (client)
7
9 version 6.17
10
12 use Net::HTTP;
13 my $s = Net::HTTP->new(Host => "www.perl.com") || die $@;
14 $s->write_request(GET => "/", 'User-Agent' => "Mozilla/5.0");
15 my($code, $mess, %h) = $s->read_response_headers;
16 while (1) {
18 my $buf;
19 my $n = $s->read_entity_body($buf, 1024);
20 die "read failed: $!" unless defined $n;
21 last unless $n;
22 print $buf;
23 }
24
26 The "Net::HTTP" class is a low-level HTTP client. An instance of the
27 "Net::HTTP" class represents a connection to an HTTP server. The HTTP
28 protocol is described in RFC 2616. The "Net::HTTP" class supports
29 "HTTP/1.0" and "HTTP/1.1".
30 "Net::HTTP" is a sub-class of one of "IO::Socket::IP" (IPv6+IPv4),
32 "IO::Socket::INET6" (IPv6+IPv4), or "IO::Socket::INET" (IPv4 only).
33 You can mix the methods described below with reading and writing from
34 the socket directly. This is not necessary a good idea, unless you
35 know what you are doing.
36 The following methods are provided (in addition to those of
38 "IO::Socket::INET"):
39 $s = Net::HTTP->new( %options )
41 The "Net::HTTP" constructor method takes the same options as
42 "IO::Socket::INET"'s as well as these:
43 Host: Initial host attribute value
45 KeepAlive: Initial keep_alive attribute value
46 SendTE: Initial send_te attribute_value
47 HTTPVersion: Initial http_version attribute value
48 PeerHTTPVersion: Initial peer_http_version attribute value
49 MaxLineLength: Initial max_line_length attribute value
50 MaxHeaderLines: Initial max_header_lines attribute value
51 The "Host" option is also the default for "IO::Socket::INET"'s
53 "PeerAddr". The "PeerPort" defaults to 80 if not provided. The
54 "PeerPort" specification can also be embedded in the "PeerAddr" by
55 preceding it with a ":", and closing the IPv6 address on brackets
56 "[]" if necessary:
57 "192.0.2.1:80","[2001:db8::1]:80","any.example.com:80".
58 The "Listen" option provided by "IO::Socket::INET"'s constructor
60 method is not allowed.
61 If unable to connect to the given HTTP server then the constructor
63 returns "undef" and $@ contains the reason. After a successful
64 connect, a "Net:HTTP" object is returned.
65 $s->host
67 Get/set the default value of the "Host" header to send. The $host
68 must not be set to an empty string (or "undef") for HTTP/1.1.
69 $s->keep_alive
71 Get/set the keep-alive value. If this value is TRUE then the
72 request will be sent with headers indicating that the server should
73 try to keep the connection open so that multiple requests can be
74 sent.
75 The actual headers set will depend on the value of the
77 "http_version" and "peer_http_version" attributes.
78 $s->send_te
80 Get/set the a value indicating if the request will be sent with a
81 "TE" header to indicate the transfer encodings that the server can
82 choose to use. The list of encodings announced as accepted by this
83 client depends on availability of the following modules:
84 "Compress::Raw::Zlib" for deflate, and "IO::Compress::Gunzip" for
85 gzip.
86 $s->http_version
88 Get/set the HTTP version number that this client should announce.
89 This value can only be set to "1.0" or "1.1". The default is
90 "1.1".
91 $s->peer_http_version
93 Get/set the protocol version number of our peer. This value will
94 initially be "1.0", but will be updated by a successful
95 read_response_headers() method call.
96 $s->max_line_length
98 Get/set a limit on the length of response line and response header
99 lines. The default is 8192. A value of 0 means no limit.
100 $s->max_header_length
102 Get/set a limit on the number of header lines that a response can
103 have. The default is 128. A value of 0 means no limit.
104 $s->format_request($method, $uri, %headers, [$content])
106 Format a request message and return it as a string. If the headers
107 do not include a "Host" header, then a header is inserted with the
108 value of the "host" attribute. Headers like "Connection" and
109 "Keep-Alive" might also be added depending on the status of the
110 "keep_alive" attribute.
111 If $content is given (and it is non-empty), then a "Content-Length"
113 header is automatically added unless it was already present.
114 $s->write_request($method, $uri, %headers, [$content])
116 Format and send a request message. Arguments are the same as for
117 format_request(). Returns true if successful.
118 $s->format_chunk( $data )
120 Returns the string to be written for the given chunk of data.
121 $s->write_chunk($data)
123 Will write a new chunk of request entity body data. This method
124 should only be used if the "Transfer-Encoding" header with a value
125 of "chunked" was sent in the request. Note, writing zero-length
126 data is a no-op. Use the write_chunk_eof() method to signal end of
127 entity body data.
128 Returns true if successful.
130 $s->format_chunk_eof( %trailers )
132 Returns the string to be written for signaling EOF when a
133 "Transfer-Encoding" of "chunked" is used.
134 $s->write_chunk_eof( %trailers )
136 Will write eof marker for chunked data and optional trailers. Note
137 that trailers should not really be used unless is was signaled with
138 a "Trailer" header.
139 Returns true if successful.
141 ($code, $mess, %headers) = $s->read_response_headers( %opts )
143 Read response headers from server and return it. The $code is the
144 3 digit HTTP status code (see HTTP::Status) and $mess is the
145 textual message that came with it. Headers are then returned as
146 key/value pairs. Since key letter casing is not normalized and the
147 same key can even occur multiple times, assigning these values
148 directly to a hash is not wise. Only the $code is returned if this
149 method is called in scalar context.
150 As a side effect this method updates the 'peer_http_version'
152 attribute.
153 Options might be passed in as key/value pairs. There are currently
155 only two options supported; "laxed" and "junk_out".
156 The "laxed" option will make read_response_headers() more forgiving
158 towards servers that have not learned how to speak HTTP properly.
159 The "laxed" option is a boolean flag, and is enabled by passing in
160 a TRUE value. The "junk_out" option can be used to capture bad
161 header lines when "laxed" is enabled. The value should be an array
162 reference. Bad header lines will be pushed onto the array.
163 The "laxed" option must be specified in order to communicate with
165 pre-HTTP/1.0 servers that don't describe the response outcome or
166 the data they send back with a header block. For these servers
167 peer_http_version is set to "0.9" and this method returns (200,
168 "Assumed OK").
169 The method will raise an exception (die) if the server does not
171 speak proper HTTP or if the "max_line_length" or
172 "max_header_length" limits are reached. If the "laxed" option is
173 turned on and "max_line_length" and "max_header_length" checks are
174 turned off, then no exception will be raised and this method will
175 always return a response code.
176 $n = $s->read_entity_body($buf, $size);
178 Reads chunks of the entity body content. Basically the same
179 interface as for read() and sysread(), but the buffer offset
180 argument is not supported yet. This method should only be called
181 after a successful read_response_headers() call.
182 The return value will be "undef" on read errors, 0 on EOF, -1 if no
184 data could be returned this time, otherwise the number of bytes
185 assigned to $buf. The $buf is set to "" when the return value is
186 -1.
187 You normally want to retry this call if this function returns
189 either -1 or "undef" with $! as EINTR or EAGAIN (see Errno). EINTR
190 can happen if the application catches signals and EAGAIN can happen
191 if you made the socket non-blocking.
192 This method will raise exceptions (die) if the server does not
194 speak proper HTTP. This can only happen when reading chunked data.
195 %headers = $s->get_trailers
197 After read_entity_body() has returned 0 to indicate end of the
198 entity body, you might call this method to pick up any trailers.
199 $s->_rbuf
201 Get/set the read buffer content. The read_response_headers() and
202 read_entity_body() methods use an internal buffer which they will
203 look for data before they actually sysread more from the socket
204 itself. If they read too much, the remaining data will be left in
205 this buffer.
206 $s->_rbuf_length
208 Returns the number of bytes in the read buffer. This should always
209 be the same as:
210 length($s->_rbuf)
212 but might be more efficient.
214
216 The read_response_headers() and read_entity_body() will invoke the
217 sysread() method when they need more data. Subclasses might want to
218 override this method to control how reading takes place.
219 The object itself is a glob. Subclasses should avoid using hash key
221 names prefixed with "http_" and "io_".
222
224 LWP, IO::Socket::INET, Net::HTTP::NB
225
227 Gisle Aas <gisle@activestate.com>
228
230 This software is copyright (c) 2001-2017 by Gisle Aas.
231 This is free software; you can redistribute it and/or modify it under
233 the same terms as the Perl 5 programming language system itself.
234perl v5.26.3 2017-09-01 Net::HTTP(3)