trunk/Meteor/Channel.pm

#!/usr/bin/perl -w
###############################################################################
#   Meteor
#   An HTTP server for the 2.0 web
#   Copyright (c) 2006 contributing authors
#
#   Channel.pm
#
#       Description:
#       A Meteor Channel
#
###############################################################################
#
#   This program is free software; you can redistribute it and/or modify it
#   under the terms of the GNU General Public License as published by the Free
#   Software Foundation; either version 2 of the License, or (at your option)
#   any later version.
#
#   This program is distributed in the hope that it will be useful, but WITHOUT
#   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
#   FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
#   more details.
#
#   You should have received a copy of the GNU General Public License along
#   with this program; if not, write to the Free Software Foundation, Inc.,
#   59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#
#   For more information visit www.meteorserver.org
#
###############################################################################

package Meteor::Channel;
###############################################################################
# Configuration
###############################################################################
        
        use strict;
        
        use Meteor::Message;
        
        our %Channels=();
        our $MessageID=0;

###############################################################################
# Class methods
###############################################################################
sub channelWithName {
        my $class=shift;
        my $channelName=shift;
        my $avoidCreation=shift;
        
        unless(exists($Channels{$channelName}))
        {
                return undef if($avoidCreation);
                #
                # Create new channel
                #
                $Channels{$channelName}=$class->newChannel($channelName);
                
                &::syslog('debug',"New channel $channelName");
        }
        
        return $Channels{$channelName};
}

sub listChannels {
        my $class=shift;
        
        my $list='';
        foreach my $channelName (sort keys %Channels)
        {
                my $channel=$Channels{$channelName};
                
                $list.=$channelName.'('.$channel->messageCount().'/'.$channel->subscriberCount().")$::CRLF";
        }
        
        $list;
}

sub deleteChannel {
        my $class=shift;
        my $channelName=shift;
        
        delete($Channels{$channelName});
}

sub trimMessageStoresByTimestamp {
        my $class=shift;
        my $minTimeStamp=shift;
        
        return unless($minTimeStamp);
        
        map { $_->trimMessageStoreByTimestamp($minTimeStamp) } (values %Channels);
}

sub clearAllBuffers {
        my $class=shift;
        
        map { $_->clearBuffer() } (values %Channels);
}

sub numChannels {
        
        return scalar(keys %Channels);
}

###############################################################################
# Factory methods
###############################################################################
sub new {
        #
        # Create a new empty instance
        #
        my $class=shift;
        
        my $obj={};
        
        bless($obj,$class);
}
        
sub newChannel {
        #
        # new instance from new server connection
        #
        my $self=shift->new();
        
        my $name=shift;
        $self->{'name'}=$name;
        
        $self->{'subscribers'}=[];
        $self->{'messages'}=[];
        
        $self;
}

sub DESTROY {
        my $self=shift;
        
        my @subscribers=@{$self->{'subscribers'}};
        map { $_->closeChannel($self->{'name'}) } @subscribers;
}

###############################################################################
# Instance methods
###############################################################################
sub name {
        shift->{'name'};
}

sub addSubscriber {
        my $self=shift;
        my $subscriber=shift;
        my $startId=shift;
        my $persist=shift;
        my $mode=shift || '';
        my $userAgent=shift || '';
        
        # Note: negative $startId means go back that many messages
        my $startIndex=$self->indexForMessageID($startId);
        my $logStartIndex = $startIndex || $self->lastMsgID() || 0;
        
        push(@{$self->{'subscribers'}},$subscriber) if($persist);
        
        &::syslog('info','',
                'joinchannel',
                $subscriber->{'socketFN'},
                $self->{'name'},
                $logStartIndex
        );
        
        return unless(defined($startIndex));
        
        my $msgCount=scalar(@{$self->{'messages'}});
        my $txt='';
        
        $startIndex=0 if($startIndex<0);
        
        if($startIndex<$msgCount) {
                $subscriber->sendMessages(@{$self->{'messages'}}[$startIndex..$msgCount-1]);
        }
}

sub removeSubscriber {
        my $self=shift;
        my $subscriber=shift;
        my $reason=shift ||'unknown';
        
        my $idx=undef;
        my $numsubs = scalar(@{$self->{'subscribers'}});

        for (my $i=0; $i<$numsubs; $i++) {
                if($self->{'subscribers'}->[$i]==$subscriber) {
                        $idx=$i;
                        last;
                }
        }
        
        if(defined($idx))
        {
                splice(@{$self->{'subscribers'}},$idx,1);
                
                my $timeConnected = time - $subscriber->{'connectionStart'};
                &::syslog('info','',
                        'leavechannel',
                        $subscriber->{'ip'},
                        $subscriber->{'subscriberID'},
                        $self->{'name'},
                        $timeConnected,
                        $subscriber->{'messageCount'},
                        $subscriber->{'bytesWritten'},
                        $reason
                );
        }
        
        $self->checkExpiration();
}

sub subscriberCount {
        my $self=shift;
        
        scalar(@{$self->{'subscribers'}});
}

sub addMessage {
        my $self=shift;
        my $messageText=shift;
        
        my $message=Meteor::Message->newWithID($MessageID++);
        $message->setText($messageText);
        $message->setChannelName($self->{'name'});
        push(@{$self->{'messages'}},$message);
        &::syslog('debug',"New message ".$message->{"id"}." on channel ".$self->{'name'});
        
        $self->trimMessageStoreBySize();
        
        map { $_->sendMessages($message) } @{$self->{'subscribers'}};
        
        $message;
}

sub messageCount {
        my $self=shift;
        
        scalar(@{$self->{'messages'}});
}

sub trimMessageStoreBySize {
        my $self=shift;
        
        my $numMessages=scalar(@{$self->{'messages'}});
        
        if($numMessages>$::CONF{'MaxMessagesPerChannel'})
        {
                splice(@{$self->{'messages'}},0,-$::CONF{'MaxMessagesPerChannel'});
        }
}

sub trimMessageStoreByTimestamp {
        my $self=shift;
        my $ts=shift;
        
        while(scalar(@{$self->{'messages'}})>0 && $self->{'messages'}->[0]->timestamp()<$ts)
        {
                my $msg=shift(@{$self->{'messages'}});
        }
        
        $self->checkExpiration();
}

sub clearBuffer {
        my $self=shift;
        
        $self->{'messages'}=[];
        
        $self->checkExpiration();
}

sub checkExpiration {
        my $self=shift;
        
        if($self->messageCount()==0 && $self->subscriberCount()==0)
        {
                my $name=$self->name();
                &::syslog('debug',"Channel expired: $name");
                $self->deleteChannel($name);
        }
}

sub indexForMessageID {
        my $self=shift;
        my $id=shift;
        
        # the messages is always sorted by ID, so we can
        # use a binary search to find the message.
        # return undef if there are no messages or the
        # ID is that of the last message.
        # Otherwise return the ID of the found message
        # of if no message with that ID exists the one
        # with the next higher ID
        #
        return undef unless(defined($id));
        
        my $numMessages=scalar(@{$self->{'messages'}});
        
        return undef unless($numMessages);
        return -1 unless($id ne '');
        
        # Note: negative $id means go back that many messages
        return $numMessages+$id if($id<0);
        
        my $low=0;
        my $high=$numMessages-1;
        my $mid;
        my $cond;
        while($low<=$high)
        {
                $mid=($low+$high)>>1;
                $cond=$id <=> $self->{'messages'}->[$mid]->id();
                if($cond<0)
                {
                        $high=$mid-1;
                }
                elsif($cond>0)
                {
                        $low=$mid+1;
                }
                else
                {
                        return $mid;
                }
        }
        
        return undef if($low>=$numMessages);
        
        return $low;
}

sub lastMsgID {
        my $self=shift;
        my $numMessages=scalar(@{$self->{'messages'}});
        return undef unless($numMessages>0);
        @{$self->{'messages'}}[-1]->id();
}

sub descriptionWithTemplate {
        my $self=shift;
        my $template=shift;
        
        return '' unless(defined($template) && $template ne '');
        
        $template=~s/~([a-zA-Z0-9_]*)~/
                if(!defined($1) || $1 eq '') {
                        '~';
                } elsif($1 eq 'messageCount') {
                        $self->messageCount();
                } elsif($1 eq 'subscriberCount') {
                        $self->subscriberCount();
                } elsif($1 eq 'lastMsgID') {
                        $self->lastMsgID() || 1;
                } elsif($1 eq 'name') {
                        $self->{'name'};
                } else {
                        '';
                }
        /gex;
        
        $template;
}

1;
############################################################################EOF
1	knops.gerd	11	#!/usr/bin/perl -w
2			###############################################################################
3			# Meteor
4			# An HTTP server for the 2.0 web
5			# Copyright (c) 2006 contributing authors
6			#
7	andrew.betts	62	# Channel.pm
8	knops.gerd	11	#
9			# Description:
10			# A Meteor Channel
11			#
12			###############################################################################
13			#
14			# This program is free software; you can redistribute it and/or modify it
15			# under the terms of the GNU General Public License as published by the Free
16			# Software Foundation; either version 2 of the License, or (at your option)
17			# any later version.
18			#
19			# This program is distributed in the hope that it will be useful, but WITHOUT
20			# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
21			# FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
22			# more details.
23			#
24			# You should have received a copy of the GNU General Public License along
25			# with this program; if not, write to the Free Software Foundation, Inc.,
26			# 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
27			#
28			# For more information visit www.meteorserver.org
29			#
30			###############################################################################
31
32			package Meteor::Channel;
33			###############################################################################
34			# Configuration
35			###############################################################################
36
37			use strict;
38
39			use Meteor::Message;
40
41			our %Channels=();
42			our $MessageID=0;
43
44			###############################################################################
45			# Class methods
46			###############################################################################
47			sub channelWithName {
48			my $class=shift;
49			my $channelName=shift;
50			my $avoidCreation=shift;
51
52			unless(exists($Channels{$channelName}))
53			{
54			return undef if($avoidCreation);
55			#
56			# Create new channel
57			#
58			$Channels{$channelName}=$class->newChannel($channelName);
59
60			&::syslog('debug',"New channel $channelName");
61			}
62
63			return $Channels{$channelName};
64			}
65
66			sub listChannels {
67			my $class=shift;
68
69			my $list='';
70			foreach my $channelName (sort keys %Channels)
71			{
72			my $channel=$Channels{$channelName};
73
74			$list.=$channelName.'('.$channel->messageCount().'/'.$channel->subscriberCount().")$::CRLF";
75			}
76
77			$list;
78			}
79
80			sub deleteChannel {
81			my $class=shift;
82			my $channelName=shift;
83
84			delete($Channels{$channelName});
85			}
86
87			sub trimMessageStoresByTimestamp {
88			my $class=shift;
89			my $minTimeStamp=shift;
90
91			return unless($minTimeStamp);
92
93			map { $_->trimMessageStoreByTimestamp($minTimeStamp) } (values %Channels);
94			}
95
96			sub clearAllBuffers {
97			my $class=shift;
98
99			map { $_->clearBuffer() } (values %Channels);
100			}
101
102	knops.gerd	25	sub numChannels {
103
104			return scalar(keys %Channels);
105			}
106
107	knops.gerd	11	###############################################################################
108			# Factory methods
109			###############################################################################
110			sub new {
111			#
112			# Create a new empty instance
113			#
114			my $class=shift;
115
116			my $obj={};
117
118			bless($obj,$class);
119			}
120
121			sub newChannel {
122			#
123			# new instance from new server connection
124			#
125			my $self=shift->new();
126
127			my $name=shift;
128			$self->{'name'}=$name;
129
130			$self->{'subscribers'}=[];
131			$self->{'messages'}=[];
132
133			$self;
134			}
135
136			sub DESTROY {
137			my $self=shift;
138
139			my @subscribers=@{$self->{'subscribers'}};
140	knops.gerd	13	map { $_->closeChannel($self->{'name'}) } @subscribers;
141	knops.gerd	11	}
142
143			###############################################################################
144			# Instance methods
145			###############################################################################
146			sub name {
147			shift->{'name'};
148			}
149
150			sub addSubscriber {
151			my $self=shift;
152			my $subscriber=shift;
153			my $startId=shift;
154			my $persist=shift;
155	knops.gerd	47	my $mode=shift \|\| '';
156			my $userAgent=shift \|\| '';
157	knops.gerd	11
158			# Note: negative $startId means go back that many messages
159	andrew.betts	50	my $startIndex=$self->indexForMessageID($startId);
160			my $logStartIndex = $startIndex \|\| $self->lastMsgID() \|\| 0;
161	knops.gerd	11
162			push(@{$self->{'subscribers'}},$subscriber) if($persist);
163
164	knops.gerd	47	&::syslog('info','',
165			'joinchannel',
166	andrew.betts	62	$subscriber->{'socketFN'},
167	knops.gerd	47	$self->{'name'},
168	andrew.betts	62	$logStartIndex
169	knops.gerd	47	);
170
171	knops.gerd	11	return unless(defined($startIndex));
172
173			my $msgCount=scalar(@{$self->{'messages'}});
174			my $txt='';
175
176			$startIndex=0 if($startIndex<0);
177
178	andrew.betts	50	if($startIndex<$msgCount) {
179			$subscriber->sendMessages(@{$self->{'messages'}}[$startIndex..$msgCount-1]);
180	knops.gerd	11	}
181			}
182
183			sub removeSubscriber {
184			my $self=shift;
185			my $subscriber=shift;
186	knops.gerd	47	my $reason=shift \|\|'unknown';
187	knops.gerd	11
188			my $idx=undef;
189	andrew.betts	50	my $numsubs = scalar(@{$self->{'subscribers'}});
190	andrew.betts	53
191			for (my $i=0; $i<$numsubs; $i++) {
192			if($self->{'subscribers'}->[$i]==$subscriber) {
193	knops.gerd	11	$idx=$i;
194			last;
195			}
196			}
197
198			if(defined($idx))
199			{
200			splice(@{$self->{'subscribers'}},$idx,1);
201	knops.gerd	47
202	andrew.betts	62	my $timeConnected = time - $subscriber->{'connectionStart'};
203	knops.gerd	47	&::syslog('info','',
204			'leavechannel',
205	andrew.betts	53	$subscriber->{'ip'},
206	knops.gerd	47	$subscriber->{'subscriberID'},
207			$self->{'name'},
208	andrew.betts	50	$timeConnected,
209	andrew.betts	62	$subscriber->{'messageCount'},
210	knops.gerd	47	$subscriber->{'bytesWritten'},
211			$reason
212			);
213	knops.gerd	11	}
214
215			$self->checkExpiration();
216			}
217
218			sub subscriberCount {
219			my $self=shift;
220
221			scalar(@{$self->{'subscribers'}});
222			}
223
224			sub addMessage {
225			my $self=shift;
226			my $messageText=shift;
227
228			my $message=Meteor::Message->newWithID($MessageID++);
229	knops.gerd	16	$message->setText($messageText);
230			$message->setChannelName($self->{'name'});
231	knops.gerd	11	push(@{$self->{'messages'}},$message);
232	andrew.betts	50	&::syslog('debug',"New message ".$message->{"id"}." on channel ".$self->{'name'});
233	knops.gerd	11
234			$self->trimMessageStoreBySize();
235
236	knops.gerd	45	map { $_->sendMessages($message) } @{$self->{'subscribers'}};
237	knops.gerd	46
238			$message;
239	knops.gerd	11	}
240
241			sub messageCount {
242			my $self=shift;
243
244			scalar(@{$self->{'messages'}});
245			}
246
247			sub trimMessageStoreBySize {
248			my $self=shift;
249
250			my $numMessages=scalar(@{$self->{'messages'}});
251
252			if($numMessages>$::CONF{'MaxMessagesPerChannel'})
253			{
254			splice(@{$self->{'messages'}},0,-$::CONF{'MaxMessagesPerChannel'});
255			}
256			}
257
258			sub trimMessageStoreByTimestamp {
259			my $self=shift;
260			my $ts=shift;
261
262			while(scalar(@{$self->{'messages'}})>0 && $self->{'messages'}->[0]->timestamp()<$ts)
263			{
264			my $msg=shift(@{$self->{'messages'}});
265			}
266
267			$self->checkExpiration();
268			}
269
270			sub clearBuffer {
271			my $self=shift;
272
273			$self->{'messages'}=[];
274
275			$self->checkExpiration();
276			}
277
278			sub checkExpiration {
279			my $self=shift;
280
281			if($self->messageCount()==0 && $self->subscriberCount()==0)
282			{
283			my $name=$self->name();
284			&::syslog('debug',"Channel expired: $name");
285			$self->deleteChannel($name);
286			}
287			}
288
289			sub indexForMessageID {
290			my $self=shift;
291			my $id=shift;
292
293			# the messages is always sorted by ID, so we can
294			# use a binary search to find the message.
295			# return undef if there are no messages or the
296			# ID is that of the last message.
297			# Otherwise return the ID of the found message
298			# of if no message with that ID exists the one
299			# with the next higher ID
300			#
301			return undef unless(defined($id));
302
303	knops.gerd	46	my $numMessages=scalar(@{$self->{'messages'}});
304	knops.gerd	11
305			return undef unless($numMessages);
306			return -1 unless($id ne '');
307
308			# Note: negative $id means go back that many messages
309			return $numMessages+$id if($id<0);
310
311			my $low=0;
312			my $high=$numMessages-1;
313			my $mid;
314			my $cond;
315			while($low<=$high)
316			{
317			$mid=($low+$high)>>1;
318			$cond=$id <=> $self->{'messages'}->[$mid]->id();
319			if($cond<0)
320			{
321			$high=$mid-1;
322			}
323			elsif($cond>0)
324			{
325			$low=$mid+1;
326			}
327			else
328			{
329			return $mid;
330			}
331			}
332
333			return undef if($low>=$numMessages);
334
335			return $low;
336			}
337
338	knops.gerd	46	sub lastMsgID {
339			my $self=shift;
340			my $numMessages=scalar(@{$self->{'messages'}});
341	andrew.betts	50	return undef unless($numMessages>0);
342	knops.gerd	46	@{$self->{'messages'}}[-1]->id();
343			}
344
345	knops.gerd	45	sub descriptionWithTemplate {
346			my $self=shift;
347			my $template=shift;
348
349	andrew.betts	53	return '' unless(defined($template) && $template ne '');
350
351	knops.gerd	45	$template=~s/~([a-zA-Z0-9_]*)~/
352	andrew.betts	50	if(!defined($1) \|\| $1 eq '') {
353	knops.gerd	45	'~';
354	andrew.betts	50	} elsif($1 eq 'messageCount') {
355	knops.gerd	45	$self->messageCount();
356	andrew.betts	50	} elsif($1 eq 'subscriberCount') {
357	knops.gerd	45	$self->subscriberCount();
358	andrew.betts	50	} elsif($1 eq 'lastMsgID') {
359	andrew.betts	58	$self->lastMsgID() \|\| 1;
360	andrew.betts	50	} elsif($1 eq 'name') {
361			$self->{'name'};
362			} else {
363	knops.gerd	45	'';
364			}
365			/gex;
366
367			$template;
368			}
369
370	knops.gerd	11	1;
371	andrew.betts	3	############################################################################EOF