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Net::HTTP(3)                         User Contributed Perl Documentation                        Net::HTTP(3)



NAME
       Net::HTTP - Low-level HTTP connection (client)

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);
           die "read failed: $!" unless defined $n;
           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.  The "Net::HTTP" class
       supports "HTTP/1.0" and "HTTP/1.1".

       "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 method takes the same options as "IO::Socket::INET"'s 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 value
             PeerHTTPVersion: Initial peer_http_version attribute value
             MaxLineLength:   Initial max_line_length attribute value
             MaxHeaderLines:  Initial max_header_lines attribute value

           The "Host" option is also the default for "IO::Socket::INET"'s "PeerAddr".  The "PeerPort"
           defaults to 80 if not provided.

           The "Listen" option provided by "IO::Socket::INET"'s constructor method is not allowed.

           If unable to connect to the given HTTP server then the constructor returns "undef" and $@
           contains the reason.  After a successful connect, a "Net:HTTP" object is returned.

       $s->host
           Get/set the default value of the "Host" header to send.  The $host must not be set to an empty
           string (or "undef") for HTTP/1.1.

       $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 choose to use.  The list of encodings announced as
           accepted by this client depends on availability of the following modules: "Compress::Raw::Zlib"
           for deflate, and "IO::Compress::Gunzip" for gzip.

       $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 8192.
           A value of 0 means no limit.

       $s->max_header_length
           Get/set a limit on the number of header 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 successful.

       $s->format_chunk( $data )
           Returns the string to be written for the given chunk of data.

       $s->write_chunk($data)
           Will write a new chunk of request entity body data.  This method should only be used if the
           "Transfer-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 signal end of entity body data.

           Returns true if successful.

       $s->format_chunk_eof( %trailers )
           Returns the string to be written for signaling EOF when a "Transfer-Encoding" of "chunked" is
           used.

       $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.

       ($code, $mess, %headers) = $s->read_response_headers( %opts )
           Read response headers from server and return it.  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 even occur
           multiple times, assigning these values directly to a hash is not wise.  Only the $code is
           returned if this method is called in scalar context.

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

           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.

           The "laxed" option must be specified in order to communicate with pre-HTTP/1.0 servers that don't
           describe the response outcome or the data they send back with a header block.  For these servers
           peer_http_version is set to "0.9" and this method returns (200, "Assumed OK").

           The method will raise an exception (die) if the server does not speak proper HTTP or if the
           "max_line_length" or "max_header_length" limits are reached.  If the "laxed" option is turned on
           and "max_line_length" and "max_header_length" checks are turned off, then no exception will be
           raised and this method will always return a response code.

       $n = $s->read_entity_body($buf, $size);
           Reads chunks of the entity body content.  Basically the same interface as for read() and
           sysread(), but the buffer offset argument is not supported yet.  This method should only be
           called after a successful read_response_headers() call.

           The return value will be "undef" on read errors, 0 on EOF, -1 if no data could be returned this
           time, otherwise the number of bytes assigned to $buf.  The $buf is set to "" when the return
           value is -1.

           You normally want to retry this call if this function returns either -1 or "undef" with $! as
           EINTR or EAGAIN (see Errno).  EINTR can happen if the application catches signals and EAGAIN can
           happen if you made the socket non-blocking.

           This method will raise exceptions (die) if the server does not speak proper HTTP.  This can only
           happen when reading chunked data.

       %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.  This should always be the same as:

               length($s->_rbuf)

           but might be more efficient.

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 control 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 2001-2003 Gisle Aas.

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



perl v5.12.5                                     2011-04-17                                     Net::HTTP(3)