net::http(3)

NAME

Net::HTTP - Low-level HTTP client connection

NOTE

This module is experimental. Details of its interface is
likely to change in the future.

SYNOPSIS

use Net::HTTP;
my $s = Net::HTTP->new(Host => "www.perl.com) || die $@;
$s->write_request(GET =>  "/",  'User-Agent'  =>  "Mozilla/5.0");
my($code, $mess, %h) = $s->read_response_headers;
while (1) {
   my $buf;
   my $n = $s->read_entity_body($buf, 1024);
   last unless $n;
   print $buf;
}

DESCRIPTION

The "Net::HTTP" class is a low-level HTTP client. An
instance of the "Net::HTTP" class represents a connection
to an HTTP server. The HTTP protocol is described in RFC
2616.

"Net::HTTP" is a sub-class of "IO::Socket::INET". You can
mix the methods described below with reading and writing
from the socket directly. This is not necessary a good
idea, unless you know what you are doing.

The following methods are provided (in addition to those
of "IO::Socket::INET"):

$s = Net::HTTP->new( %options )

The "Net::HTTP" constructor takes the same options as
"IO::Socket::INET" as well as these:

Host: Initial host attribute value
KeepAlive: Initial keep_alive attribute value
SendTE: Initial send_te attribute_value
HTTPVersion: Initial http_version attribute val

ue
PeerHTTPVersion: Initial peer_http_version attribute

value
MaxLineLength: Initial max_line_length attribute

value
MaxHeaderLines: Initial max_header_lines attribute

value

$s->host

Get/set the default value of the "Host" header to
send. The $host should not be set to an empty string
(or "undef").

$s->keep_alive

Get/set the keep-alive value. If this value is TRUE then the request will be sent with headers indicating
that the server should try to keep the connection open
so that multiple requests can be sent.

The actual headers set will depend on the value of the
"http_version" and "peer_http_version" attributes.

$s->send_te

Get/set the a value indicating if the request will be
sent with a "TE" header to indicate the transfer
encodings that the server can chose to use. If the
"Compress::Zlib" module is installed then this will
annouce that this client accept both the deflate and gzip encodings.

$s->http_version

Get/set the HTTP version number that this client
should announce. This value can only be set to "1.0"
or "1.1". The default is "1.1".

$s->peer_http_version

Get/set the protocol version number of our peer. This
value will initially be "1.0", but will be updated by
a successful read_response_headers() method call.

$s->max_line_length

Get/set a limit on the length of response line and
response header lines. The default is 4096. A value
of 0 means no limit.

$s->max_header_length

Get/set a limit on the number of headers lines that a
response can have. The default is 128. A value of 0
means no limit.

$s->format_request($method, $uri, %headers, [$content])

Format a request message and return it as a string.
If the headers do not include a "Host" header, then a
header is inserted with the value of the "host"
attribute. Headers like "Connection" and "Keep-Alive"
might also be added depending on the status of the
"keep_alive" attribute.

If $content is given (and it is non-empty), then a
"Content-Length" header is automatically added unless
it was already present.

$s->write_request($method, $uri, %headers, [$content])

Format and send a request message. Arguments are the
same as for format_request(). Returns true if suc cessful.

$s->write_chunk($data)

Will write a new chunk of request entity body data.
This method should only be used if the "Trans
fer-Encoding" header with a value of "chunked" was
sent in the request. Note, writing zero-length data
is a no-op. Use the write_chunk_eof() method to sig nal end of entity body data.

Returns true if successful.

$s->format_chunk($data)

Returns the string to be written for the given chunk
of data.

$s->write_chunk_eof(%trailers)

Will write eof marker for chunked data and optional
trailers. Note that trailers should not really be
used unless is was signaled with a "Trailer" header.

Returns true if successful.

$s->format_chunk_eof(%trailers)

Returns the string to be written for signaling EOF.

($code, $mess, %headers) = $s->read_response_headers(
%opts )

Read response headers from server. The $code is the 3
digit HTTP status code (see HTTP::Status) and $mess is
the textual message that came with it. Headers are
then returned as key/value pairs. Since key letter
casing is not normalized and the same key can occur
multiple times, assigning these values directly to a
hash might be risky.

As a side effect this method updates the
'peer_http_version' attribute.

The method will raise exceptions (die) if the server
does not speak proper HTTP.

Options might be passed in as key/value pairs. There
are currently only two options supported; "laxed" and
"junk_out".

The "laxed" option will make "read_response_headers"
more forgiving towards servers that have not learned
how to speak HTTP properly. The <laxed> option is a
boolean flag, and is enabled by passing in a TRUE
value. The "junk_out" option can be used to capture
bad header lines when "laxed" is enabled. The value
should be an array reference. Bad header lines will
be pushed onto the array.

$n = $s->read_entity_body($buf, $size);

Reads chunks of the entity body content. Basically
the same interface as for read() and sysread(), but buffer offset is not supported yet. This method
should only be called after a successful
read_response_headers() call.

The return value will be "undef" on errors, 0 on EOF,
-1 if no data could be returned this time, and other
wise the number of bytes added to $buf.

This method might raise exceptions (die) if the server
does not speak proper HTTP.

%headers = $s->get_trailers

After read_entity_body() has returned 0 to indicate end of the entity body, you might call this method to
pick up any trailers.

$s->_rbuf

Get/set the read buffer content. The
read_response_headers() and read_entity_body() methods use an internal buffer which they will look for data
before they actually sysread more from the socket
itself. If they read too much, the remaining data
will be left in this buffer.

$s->_rbuf_length

Returns the number of bytes in the read buffer.

SUBCLASSING

The read_response_headers() and read_entity_body() will invoke the sysread() method when they need more data. Subclasses might want to override this method to contol
how reading takes place.

The object itself is a glob. Subclasses should avoid
using hash key names prefixed with "http_" and "io_".

SEE ALSO

LWP, IO::Socket::INET, Net::HTTP::NB

COPYRIGHT

Copyright 2001 Gisle Aas.

This library is free software; you can redistribute it
and/or modify it under the same terms as Perl itself.

libwww-perl-5.65 2001-12-03 Net::HTTP(3)