trunk/Meteor/Channel.pm

#!/usr/bin/perl -w
###############################################################################
#   Meteor
#   An HTTP server for the 2.0 web
#   Copyright (c) 2006 contributing authors
#
#   Subscriber.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 listChannelsUsingTemplate {
        my $class=shift;
        my $template=shift;
        
        return '' unless(defined($template) && $template ne '');
        
        my $list='';
        foreach my $channelName (sort keys %Channels)
        {
                my $channel=$Channels{$channelName};
                
                $list.=$channel->descriptionWithTemplate($template);
        }
        
        $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->{'subscriberID'},
                $self->{'name'},
                $mode,
                $logStartIndex,
                $userAgent
        );
        
        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->{'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;
        
        $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();
                } elsif($1 eq 'name') {
                        $self->{'name'};
                } else {
                        '';
                }
        /gex;
        
        $template;
}

1;
############################################################################EOF
1	#!/usr/bin/perl -w
2	###############################################################################
3	# Meteor
4	# An HTTP server for the 2.0 web
5	# Copyright (c) 2006 contributing authors
6	#
7	# Subscriber.pm
8	#
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 listChannelsUsingTemplate {
81	my $class=shift;
82	my $template=shift;
83
84	return '' unless(defined($template) && $template ne '');
85
86	my $list='';
87	foreach my $channelName (sort keys %Channels)
88	{
89	my $channel=$Channels{$channelName};
90
91	$list.=$channel->descriptionWithTemplate($template);
92	}
93
94	$list;
95	}
96
97	sub deleteChannel {
98	my $class=shift;
99	my $channelName=shift;
100
101	delete($Channels{$channelName});
102	}
103
104	sub trimMessageStoresByTimestamp {
105	my $class=shift;
106	my $minTimeStamp=shift;
107
108	return unless($minTimeStamp);
109
110	map { $_->trimMessageStoreByTimestamp($minTimeStamp) } (values %Channels);
111	}
112
113	sub clearAllBuffers {
114	my $class=shift;
115
116	map { $_->clearBuffer() } (values %Channels);
117	}
118
119	sub numChannels {
120
121	return scalar(keys %Channels);
122	}
123
124	###############################################################################
125	# Factory methods
126	###############################################################################
127	sub new {
128	#
129	# Create a new empty instance
130	#
131	my $class=shift;
132
133	my $obj={};
134
135	bless($obj,$class);
136	}
137
138	sub newChannel {
139	#
140	# new instance from new server connection
141	#
142	my $self=shift->new();
143
144	my $name=shift;
145	$self->{'name'}=$name;
146
147	$self->{'subscribers'}=[];
148	$self->{'messages'}=[];
149
150	$self;
151	}
152
153	sub DESTROY {
154	my $self=shift;
155
156	my @subscribers=@{$self->{'subscribers'}};
157	map { $_->closeChannel($self->{'name'}) } @subscribers;
158	}
159
160	###############################################################################
161	# Instance methods
162	###############################################################################
163	sub name {
164	shift->{'name'};
165	}
166
167	sub addSubscriber {
168	my $self=shift;
169	my $subscriber=shift;
170	my $startId=shift;
171	my $persist=shift;
172	my $mode=shift \|\| '';
173	my $userAgent=shift \|\| '';
174
175	# Note: negative $startId means go back that many messages
176	my $startIndex=$self->indexForMessageID($startId);
177	my $logStartIndex = $startIndex \|\| $self->lastMsgID() \|\| 0;
178
179	push(@{$self->{'subscribers'}},$subscriber) if($persist);
180
181	&::syslog('info','',
182	'joinchannel',
183	$subscriber->{'subscriberID'},
184	$self->{'name'},
185	$mode,
186	$logStartIndex,
187	$userAgent
188	);
189
190	return unless(defined($startIndex));
191
192	my $msgCount=scalar(@{$self->{'messages'}});
193	my $txt='';
194
195	$startIndex=0 if($startIndex<0);
196
197	if($startIndex<$msgCount) {
198	$subscriber->sendMessages(@{$self->{'messages'}}[$startIndex..$msgCount-1]);
199	}
200	}
201
202	sub removeSubscriber {
203	my $self=shift;
204	my $subscriber=shift;
205	my $reason=shift \|\|'unknown';
206
207	my $idx=undef;
208	my $numsubs = scalar(@{$self->{'subscribers'}});
209	for(my $i=0;$i<$numsubs;$i++)
210	{
211	if($self->{'subscribers'}->[$i]==$subscriber)
212	{
213	$idx=$i;
214	last;
215	}
216	}
217
218	if(defined($idx))
219	{
220	splice(@{$self->{'subscribers'}},$idx,1);
221
222	my $timeConnected = time - $subscriber->{'ConnectionStart'};
223	&::syslog('info','',
224	'leavechannel',
225	$subscriber->{'subscriberID'},
226	$self->{'name'},
227	$timeConnected,
228	$subscriber->{'MessageCount'},
229	$subscriber->{'bytesWritten'},
230	$reason
231	);
232	}
233
234	$self->checkExpiration();
235	}
236
237	sub subscriberCount {
238	my $self=shift;
239
240	scalar(@{$self->{'subscribers'}});
241	}
242
243	sub addMessage {
244	my $self=shift;
245	my $messageText=shift;
246
247	my $message=Meteor::Message->newWithID($MessageID++);
248	$message->setText($messageText);
249	$message->setChannelName($self->{'name'});
250	push(@{$self->{'messages'}},$message);
251	&::syslog('debug',"New message ".$message->{"id"}." on channel ".$self->{'name'});
252
253	$self->trimMessageStoreBySize();
254
255	map { $_->sendMessages($message) } @{$self->{'subscribers'}};
256
257	$message;
258	}
259
260	sub messageCount {
261	my $self=shift;
262
263	scalar(@{$self->{'messages'}});
264	}
265
266	sub trimMessageStoreBySize {
267	my $self=shift;
268
269	my $numMessages=scalar(@{$self->{'messages'}});
270
271	if($numMessages>$::CONF{'MaxMessagesPerChannel'})
272	{
273	splice(@{$self->{'messages'}},0,-$::CONF{'MaxMessagesPerChannel'});
274	}
275	}
276
277	sub trimMessageStoreByTimestamp {
278	my $self=shift;
279	my $ts=shift;
280
281	while(scalar(@{$self->{'messages'}})>0 && $self->{'messages'}->[0]->timestamp()<$ts)
282	{
283	my $msg=shift(@{$self->{'messages'}});
284	}
285
286	$self->checkExpiration();
287	}
288
289	sub clearBuffer {
290	my $self=shift;
291
292	$self->{'messages'}=[];
293
294	$self->checkExpiration();
295	}
296
297	sub checkExpiration {
298	my $self=shift;
299
300	if($self->messageCount()==0 && $self->subscriberCount()==0)
301	{
302	my $name=$self->name();
303	&::syslog('debug',"Channel expired: $name");
304	$self->deleteChannel($name);
305	}
306	}
307
308	sub indexForMessageID {
309	my $self=shift;
310	my $id=shift;
311
312	# the messages is always sorted by ID, so we can
313	# use a binary search to find the message.
314	# return undef if there are no messages or the
315	# ID is that of the last message.
316	# Otherwise return the ID of the found message
317	# of if no message with that ID exists the one
318	# with the next higher ID
319	#
320	return undef unless(defined($id));
321
322	my $numMessages=scalar(@{$self->{'messages'}});
323
324	return undef unless($numMessages);
325	return -1 unless($id ne '');
326
327	# Note: negative $id means go back that many messages
328	return $numMessages+$id if($id<0);
329
330	my $low=0;
331	my $high=$numMessages-1;
332	my $mid;
333	my $cond;
334	while($low<=$high)
335	{
336	$mid=($low+$high)>>1;
337	$cond=$id <=> $self->{'messages'}->[$mid]->id();
338	if($cond<0)
339	{
340	$high=$mid-1;
341	}
342	elsif($cond>0)
343	{
344	$low=$mid+1;
345	}
346	else
347	{
348	return $mid;
349	}
350	}
351
352	return undef if($low>=$numMessages);
353
354	return $low;
355	}
356
357	sub lastMsgID {
358	my $self=shift;
359	my $numMessages=scalar(@{$self->{'messages'}});
360	return undef unless($numMessages>0);
361	@{$self->{'messages'}}[-1]->id();
362	}
363
364	sub descriptionWithTemplate {
365	my $self=shift;
366	my $template=shift;
367
368	$template=~s/~([a-zA-Z0-9_]*)~/
369	if(!defined($1) \|\| $1 eq '') {
370	'~';
371	} elsif($1 eq 'messageCount') {
372	$self->messageCount();
373	} elsif($1 eq 'subscriberCount') {
374	$self->subscriberCount();
375	} elsif($1 eq 'lastMsgID') {
376	$self->lastMsgID();
377	} elsif($1 eq 'name') {
378	$self->{'name'};
379	} else {
380	'';
381	}
382	/gex;
383
384	$template;
385	}
386
387	1;
388	############################################################################EOF