| Net::HTTP - Low-level HTTP connection |
Net::HTTP - Low-level HTTP connection (client)
version 6.19
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;
}
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 one of IO::Socket::IP (IPv6+IPv4),
IO::Socket::INET6 (IPv6+IPv4), or IO::Socket::INET (IPv4 only).
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):
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 PeerPort specification can also be embedded in the PeerAddr
by preceding it with a ``:'', and closing the IPv6 address on brackets ``[]'' if
necessary: ``192.0.2.1:80'',``[2001:db8::1]:80'',``any.example.com:80''.
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.
Host header to send. The $host
must not be set to an empty string (or undef) for HTTP/1.1.
The actual headers set will depend on the value of the http_version
and peer_http_version attributes.
Compress::Raw::Zlib for
deflate, and IO::Compress::Gunzip for gzip.
read_response_headers() method call.
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 $content is given (and it is non-empty), then a Content-Length
header is automatically added unless it was already present.
write_chunk($data)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.
Transfer-Encoding of chunked is used.
Trailer header.
Returns true if successful.
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.
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 $! as EINTR or EAGAIN (see the Errno manpage). EINTR
can happen if the application catches signals and EAGAIN can happen if
you made the socket non-blocking.
This method will raise exceptions (die) if the server does not speak proper HTTP. This can only happen when reading chunked data.
read_entity_body() has returned 0 to indicate end of the entity
body, you might call this method to pick up any trailers.
read_response_headers() and
read_entity_body() methods use an internal buffer which they will look
for data before they actually sysread more from the socket itself. If
they read too much, the remaining data will be left in this buffer.
length($s->_rbuf)
but might be more efficient.
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_.
the LWP manpage, the IO::Socket::INET manpage, the Net::HTTP::NB manpage
Gisle Aas <gisle@activestate.com>
This software is copyright (c) 2001-2017 by Gisle Aas.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.
| Net::HTTP - Low-level HTTP connection |