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- #
- # $Id: nntp.pm,v 1.8 1998/11/19 21:45:02 aas Exp $
-
- # Implementation of the Network News Transfer Protocol (RFC 977)
- #
-
- package LWP::Protocol::nntp;
-
- require LWP::Protocol;
- @ISA = qw(LWP::Protocol);
-
- require LWP::Debug;
- require HTTP::Response;
- require HTTP::Status;
- require Net::NNTP;
-
- use strict;
-
-
- sub request
- {
- my($self, $request, $proxy, $arg, $size, $timeout) = @_;
-
- LWP::Debug::trace('()');
-
- $size = 4096 unless $size;
-
- # Check for proxy
- if (defined $proxy) {
- return HTTP::Response->new(&HTTP::Status::RC_BAD_REQUEST,
- 'You can not proxy through NNTP');
- }
-
- # Check that the scheme is as expected
- my $url = $request->url;
- my $scheme = $url->scheme;
- unless ($scheme eq 'news') {
- return HTTP::Response->new(&HTTP::Status::RC_INTERNAL_SERVER_ERROR,
- "LWP::Protocol::nntp::request called for '$scheme'");
- }
-
- # check for a valid method
- my $method = $request->method;
- unless ($method eq 'GET' || $method eq 'HEAD' || $method eq 'POST') {
- return HTTP::Response->new(&HTTP::Status::RC_BAD_REQUEST,
- 'Library does not allow method ' .
- "$method for 'news:' URLs");
- }
-
- # extract the identifier and check against posting to an article
- my $groupart = $url->_group;
- my $is_art = $groupart =~ /@/;
-
- if ($is_art && $method eq 'POST') {
- return HTTP::Response->new(&HTTP::Status::RC_BAD_REQUEST,
- "Can't post to an article <$groupart>");
- }
-
- my $nntp = Net::NNTP->new(undef,
- #Port => 18574,
- Timeout => $timeout,
- #Debug => 1,
- );
- die "Can't connect to nntp server" unless $nntp;
-
- # Check the initial welcome message from the NNTP server
- if ($nntp->status != 2) {
- return HTTP::Response->new(&HTTP::Status::RC_SERVICE_UNAVAILABLE,
- $nntp->message);
- }
- my $response = HTTP::Response->new(&HTTP::Status::RC_OK, "OK");
-
- my $mess = $nntp->message;
- LWP::Debug::debug($mess);
-
- # Try to extract server name from greating message.
- # Don't know if this works well for a large class of servers, but
- # this works for our server.
- $mess =~ s/\s+ready\b.*//;
- $mess =~ s/^\S+\s+//;
- $response->header(Server => $mess);
-
-
- # First we handle posting of articles
- if ($method eq 'POST') {
- return HTTP::Response->new(&HTTP::Status::RC_NOT_IMPLEMENTED,
- "POST not implemented yet");
- }
-
- # The method must be "GET" or "HEAD" by now
- if (!$is_art) {
- if (!$nntp->group($groupart)) {
- return HTTP::Response->new(&HTTP::Status::RC_NOT_FOUND,
- $nntp->message);
- }
- return HTTP::Response->new(&HTTP::Status::RC_NOT_IMPLEMENTED,
- "GET newsgroup not implemented yet");
- }
-
- # Send command to server to retrieve an article (or just the headers)
- my $get = $method eq 'HEAD' ? "head" : "article";
- my $art = $nntp->$get("<$groupart>");
- unless ($art) {
- return HTTP::Response->new(&HTTP::Status::RC_NOT_FOUND,
- $nntp->message);
- }
- LWP::Debug::debug($nntp->message);
-
- # Parse headers
- my($key, $val);
- while ($_ = shift @$art) {
- if (/^\s+$/) {
- last; # end of headers
- } elsif (/^(\S+):\s*(.*)/) {
- $response->push_header($key, $val) if $key;
- ($key, $val) = ($1, $2);
- } elsif (/^\s+(.*)/) {
- next unless $key;
- $val .= $1;
- } else {
- unshift(@$art, $_);
- last;
- }
- }
- $response->push_header($key, $val) if $key;
-
- # Ensure that there is a Content-Type header
- $response->header("Content-Type", "text/plain")
- unless $response->header("Content-Type");
-
- # Collect the body
- $response = $self->collect_once($arg, $response, join("", @$art))
- if @$art;
-
- # Say godbye to the server
- $nntp->quit;
- $nntp = undef;
-
- $response;
- }
-
- 1;
-