# documentation in manual or html file format (these utilities are part of the
# Perl 5 distribution).
-# Copyright 1995,1996, Lincoln D. Stein. All rights reserved.
+# Copyright 1995-2000, Lincoln D. Stein. All rights reserved.
# It may be used and modified freely, but I do request that this copyright
# notice remain attached to the file. You may modify this module as you
# wish, but if you redistribute a modified version, please attach a note
# The most recent version and complete docs are available at:
# http://stein.cshl.org/WWW/software/CGI/
-$CGI::Push::VERSION='1.02';
+$CGI::Push::VERSION='1.04';
use CGI;
use CGI::Util 'rearrange';
@ISA = ('CGI');
# unbuffer output
$| = 1;
srand;
- my ($random) = sprintf("%16.0f",rand()*1E16);
- my ($boundary) = "----------------------------------$random";
+ my ($random) = sprintf("%08.0f",rand()*1E8);
+ my ($boundary) = "----=_NeXtPaRt$random";
my (@header);
- my ($type,$callback,$delay,$last_page,$cookie,$target,$expires,@other) =
- rearrange([TYPE,NEXT_PAGE,DELAY,LAST_PAGE,[COOKIE,COOKIES],TARGET,EXPIRES],@p);
+ my ($type,$callback,$delay,$last_page,$cookie,$target,$expires,$nph,@other) = rearrange([TYPE,NEXT_PAGE,DELAY,LAST_PAGE,[COOKIE,COOKIES],TARGET,EXPIRES,NPH],@p);
$type = 'text/html' unless $type;
$callback = \&simple_counter unless $callback && ref($callback) eq 'CODE';
$delay = 1 unless defined($delay);
$self->push_delay($delay);
+ $nph = 1 unless defined($nph);
my(@o);
foreach (@other) { push(@o,split("=")); }
push(@o,'-Target'=>$target) if defined($target);
push(@o,'-Cookie'=>$cookie) if defined($cookie);
- push(@o,'-Type'=>"multipart/x-mixed-replace; boundary=$boundary");
- push(@o,'-Server'=>"CGI.pm Push Module");
+ push(@o,'-Type'=>"multipart/x-mixed-replace;boundary=\"$boundary\"");
+ push(@o,'-Server'=>"CGI.pm Push Module") if $nph;
push(@o,'-Status'=>'200 OK');
- push(@o,'-nph'=>1);
+ push(@o,'-nph'=>1) if $nph;
print $self->header(@o);
- print "${boundary}$CGI::CRLF";
+
+ $boundary = "$CGI::CRLF--$boundary";
+
+ print "WARNING: YOUR BROWSER DOESN'T SUPPORT THIS SERVER-PUSH TECHNOLOGY.${boundary}$CGI::CRLF";
+
+ my (@contents) = &$callback($self,++$COUNTER);
# now we enter a little loop
- my @contents;
while (1) {
- last unless (@contents = &$callback($self,++$COUNTER)) && defined($contents[0]);
- print "Content-type: ${type}$CGI::CRLF$CGI::CRLF"
- unless $type eq 'dynamic';
- print @contents,"$CGI::CRLF";
- print "${boundary}$CGI::CRLF";
- do_sleep($self->push_delay()) if $self->push_delay();
- }
-
- # Optional last page
- if ($last_page && ref($last_page) eq 'CODE') {
- print "Content-type: ${type}$CGI::CRLF$CGI::CRLF" unless $type =~ /^dynamic|heterogeneous$/i;
- print &$last_page($self,$COUNTER),"$CGI::CRLF${boundary}$CGI::CRLF";
+ print "Content-type: ${type}$CGI::CRLF$CGI::CRLF" unless $type =~ /^dynamic|heterogeneous$/i;
+ print @contents;
+ @contents = &$callback($self,++$COUNTER);
+ if ((@contents) && defined($contents[0])) {
+ print "${boundary}$CGI::CRLF";
+ do_sleep($self->push_delay()) if $self->push_delay();
+ } else {
+ if ($last_page && ref($last_page) eq 'CODE') {
+ print "${boundary}$CGI::CRLF";
+ do_sleep($self->push_delay()) if $self->push_delay();
+ print "Content-type: ${type}$CGI::CRLF$CGI::CRLF" unless $type =~ /^dynamic|heterogeneous$/i;
+ print &$last_page($self,$COUNTER);
+ }
+ print "${boundary}--$CGI::CRLF";
+ last;
+ }
}
+ print "WARNING: YOUR BROWSER DOESN'T SUPPORT THIS SERVER-PUSH TECHNOLOGY.$CGI::CRLF";
}
sub simple_counter {
my ($self,$count) = @_;
- return (
- CGI->start_html("CGI::Push Default Counter"),
- CGI->h1("CGI::Push Default Counter"),
- "This page has been updated ",CGI->strong($count)," times.",
- CGI->hr(),
- CGI->a({'-href'=>'http://www.genome.wi.mit.edu/ftp/pub/software/WWW/cgi_docs.html'},'CGI.pm home page'),
- CGI->end_html
- );
+ return $self->start_html("CGI::Push Default Counter"),
+ $self->h1("CGI::Push Default Counter"),
+ "This page has been updated ",$self->strong($count)," times.",
+ $self->hr(),
+ $self->a({'-href'=>'http://www.genome.wi.mit.edu/ftp/pub/software/WWW/cgi_docs.html'},'CGI.pm home page'),
+ $self->end_html;
}
sub do_sleep {
my $delay = shift;
if ( ($delay >= 1) && ($delay!~/\./) ){
- sleep($delay);
+ sleep($delay);
} else {
- select(undef,undef,undef,$delay);
+ select(undef,undef,undef,$delay);
}
}
sub push_delay {
- my ($self,$delay) = CGI::self_or_default(@_);
- return defined($delay) ? $self->{'.delay'} =
- $delay : $self->{'.delay'};
+ my ($self,$delay) = CGI::self_or_default(@_);
+ return defined($delay) ? $self->{'.delay'} =
+ $delay : $self->{'.delay'};
}
1;
my($q,$counter) = @_;
return undef if $counter >= 10;
return start_html('Test'),
- h1('Visible'),"\n",
+ h1('Visible'),"\n",
"This page has been called ", strong($counter)," times",
end_html();
- }
+ }
- sub last_page {
- my($q,$counter) = @_;
- return start_html('Done'),
- h1('Finished'),
- strong($counter),' iterations.',
- end_html;
- }
+ sub last_page {
+ my($q,$counter) = @_;
+ return start_html('Done'),
+ h1('Finished'),
+ strong($counter - 1),' iterations.',
+ end_html;
+ }
=head1 DESCRIPTION
return undef if $counter > 100;
return start_html('testing'),
h1('testing'),
- "This page called $counter times";
+ "This page called $counter times";
}
You are of course free to refer to create and use global variables
B<If not specified, -delay will default to 1 second>
-=item -cookie, -target, -expires
+=item -cookie, -target, -expires, -nph
These have the same meaning as the like-named parameters in
CGI::header().
+If not specified, -nph will default to 1 (as needed for many servers, see below).
+
=back
=head2 Heterogeneous Pages
sub my_draw_routine {
my($q,$counter) = @_;
return header('text/html'), # note we're producing the header here
- start_html('testing'),
+ start_html('testing'),
h1('testing'),
- "This page called $counter times";
+ "This page called $counter times";
}
You can add any header fields that you like, but some (cookies and
sub my_draw_routine {
my($q,$counter) = @_;
- return undef if $counter > 10;
+ return undef if $counter > 10;
return header('text/html'), # note we're producing the header here
- start_html('testing'),
+ start_html('testing'),
h1('testing'),
- "This page called $counter times";
+ "This page called $counter times";
}
sub my_last_page {
- header(-refresh=>'5; URL=http://somewhere.else/finished.html',
- -type=>'text/html'),
- start_html('Moved'),
- h1('This is the last page'),
- 'Goodbye!'
- hr,
- end_html;
+ return header(-refresh=>'5; URL=http://somewhere.else/finished.html',
+ -type=>'text/html'),
+ start_html('Moved'),
+ h1('This is the last page'),
+ 'Goodbye!'
+ hr,
+ end_html;
}
=head2 Changing the Page Delay on the Fly
=head1 INSTALLING CGI::Push SCRIPTS
-Server push scripts B<must> be installed as no-parsed-header (NPH)
-scripts in order to work correctly. On Unix systems, this is most
-often accomplished by prefixing the script's name with "nph-".
+Server push scripts must be installed as no-parsed-header (NPH)
+scripts in order to work correctly on many servers. On Unix systems,
+this is most often accomplished by prefixing the script's name with "nph-".
Recognition of NPH scripts happens automatically with WebSTAR and
Microsoft IIS. Users of other servers should see their documentation
for help.
+Apache web server from version 1.3b2 on does not need server
+push scripts installed as NPH scripts: the -nph parameter to do_push()
+may be set to a false value to disable the extra headers needed by an
+NPH script.
+
=head1 AUTHOR INFORMATION
Copyright 1995-1998, Lincoln D. Stein. All rights reserved.