1: #!/usr/bin/perl
2:
3: # The LearningOnline Network
4: # lonsql - LON TCP-MySQL-Server Daemon for handling database requests.
5: #
6: # $Id: lonsql,v 1.45 2002/06/17 20:25:51 www Exp $
7: #
8: # Copyright Michigan State University Board of Trustees
9: #
10: # This file is part of the LearningOnline Network with CAPA (LON-CAPA).
11: #
12: # LON-CAPA is free software; you can redistribute it and/or modify
13: # it under the terms of the GNU General Public License as published by
14: # the Free Software Foundation; either version 2 of the License, or
15: # (at your option) any later version.
16: #
17: # LON-CAPA is distributed in the hope that it will be useful,
18: # but WITHOUT ANY WARRANTY; without even the implied warranty of
19: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20: # GNU General Public License for more details.
21: #
22: # You should have received a copy of the GNU General Public License
23: # along with LON-CAPA; if not, write to the Free Software
24: # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25: #
26: # /home/httpd/html/adm/gpl.txt
27: #
28: # http://www.lon-capa.org/
29: #
30: # YEAR=2000
31: # lonsql-based on the preforker:harsha jagasia:date:5/10/00
32: # 7/25 Gerd Kortemeyer
33: # many different dates Scott Harrison
34: # YEAR=2001
35: # many different dates Scott Harrison
36: # 03/22/2001 Scott Harrison
37: # 8/30 Gerd Kortemeyer
38: # 10/17,11/28,11/29,12/20 Scott Harrison
39: # YEAR=2001
40: # 5/11 Scott Harrison
41: #
42: ###
43:
44: ###############################################################################
45: ## ##
46: ## ORGANIZATION OF THIS PERL SCRIPT ##
47: ## 1. Modules used ##
48: ## 2. Enable find subroutine ##
49: ## 3. Read httpd config files and get variables ##
50: ## 4. Make sure that database can be accessed ##
51: ## 5. Make sure this process is running from user=www ##
52: ## 6. Check if other instance is running ##
53: ## 7. POD (plain old documentation, CPAN style) ##
54: ## ##
55: ###############################################################################
56:
57: use lib '/home/httpd/lib/perl/';
58: use LONCAPA::Configuration;
59:
60: use IO::Socket;
61: use Symbol;
62: use POSIX;
63: use IO::Select;
64: use IO::File;
65: use Socket;
66: use Fcntl;
67: use Tie::RefHash;
68: use DBI;
69:
70: my @metalist;
71: # ----------------- Code to enable 'find' subroutine listing of the .meta files
72: require "find.pl";
73: sub wanted {
74: (($dev,$ino,$mode,$nlink,$uid,$gid) = lstat($_)) &&
75: -f _ &&
76: /^.*\.meta$/ && !/^.+\.\d+\.[^\.]+\.meta$/ &&
77: push(@metalist,"$dir/$_");
78: }
79:
80: $childmaxattempts=10;
81: $run =0;#running counter to generate the query-id
82:
83: # -------------------------------- Read loncapa_apache.conf and loncapa.conf
84: my $perlvarref=LONCAPA::Configuration::read_conf('loncapa_apache.conf',
85: 'loncapa.conf');
86: my %perlvar=%{$perlvarref};
87:
88: # ------------------------------------- Make sure that database can be accessed
89: {
90: my $dbh;
91: unless (
92: $dbh = DBI->connect("DBI:mysql:loncapa","www",$perlvar{'lonSqlAccess'},{ RaiseError =>0,PrintError=>0})
93: ) {
94: print "Cannot connect to database!\n";
95: $emailto="$perlvar{'lonAdmEMail'},$perlvar{'lonSysEMail'}";
96: $subj="LON: $perlvar{'lonHostID'} Cannot connect to database!";
97: system("echo 'Cannot connect to MySQL database!' |\
98: mailto $emailto -s '$subj' > /dev/null");
99: exit 1;
100: }
101: else {
102: $dbh->disconnect;
103: }
104: }
105:
106: # --------------------------------------------- Check if other instance running
107:
108: my $pidfile="$perlvar{'lonDaemons'}/logs/lonsql.pid";
109:
110: if (-e $pidfile) {
111: my $lfh=IO::File->new("$pidfile");
112: my $pide=<$lfh>;
113: chomp($pide);
114: if (kill 0 => $pide) { die "already running"; }
115: }
116:
117: # ------------------------------------------------------------- Read hosts file
118: $PREFORK=4; # number of children to maintain, at least four spare
119:
120: open (CONFIG,"$perlvar{'lonTabDir'}/hosts.tab") || die "Can't read host file";
121:
122: while ($configline=<CONFIG>) {
123: my ($id,$domain,$role,$name,$ip)=split(/:/,$configline);
124: chomp($ip);
125:
126: $hostip{$ip}=$id;
127: if ($id eq $perlvar{'lonHostID'}) { $thisserver=$name; }
128:
129: $PREFORK++;
130: }
131: close(CONFIG);
132:
133: $PREFORK=int($PREFORK/4);
134:
135: $unixsock = "mysqlsock";
136: my $localfile="$perlvar{'lonSockDir'}/$unixsock";
137: my $server;
138: unlink ($localfile);
139: unless ($server=IO::Socket::UNIX->new(Local =>"$localfile",
140: Type => SOCK_STREAM,
141: Listen => 10))
142: {
143: print "in socket error:$@\n";
144: }
145:
146: # -------------------------------------------------------- Routines for forking
147: # global variables
148: $MAX_CLIENTS_PER_CHILD = 5; # number of clients each child should process
149: %children = (); # keys are current child process IDs
150: $children = 0; # current number of children
151:
152: sub REAPER { # takes care of dead children
153: $SIG{CHLD} = \&REAPER;
154: my $pid = wait;
155: $children --;
156: &logthis("Child $pid died");
157: delete $children{$pid};
158: }
159:
160: sub HUNTSMAN { # signal handler for SIGINT
161: local($SIG{CHLD}) = 'IGNORE'; # we're going to kill our children
162: kill 'INT' => keys %children;
163: my $execdir=$perlvar{'lonDaemons'};
164: unlink("$execdir/logs/lonsql.pid");
165: &logthis("<font color=red>CRITICAL: Shutting down</font>");
166: $unixsock = "mysqlsock";
167: my $port="$perlvar{'lonSockDir'}/$unixsock";
168: unlink(port);
169: exit; # clean up with dignity
170: }
171:
172: sub HUPSMAN { # signal handler for SIGHUP
173: local($SIG{CHLD}) = 'IGNORE'; # we're going to kill our children
174: kill 'INT' => keys %children;
175: close($server); # free up socket
176: &logthis("<font color=red>CRITICAL: Restarting</font>");
177: my $execdir=$perlvar{'lonDaemons'};
178: $unixsock = "mysqlsock";
179: my $port="$perlvar{'lonSockDir'}/$unixsock";
180: unlink(port);
181: exec("$execdir/lonsql"); # here we go again
182: }
183:
184: sub logthis {
185: my $message=shift;
186: my $execdir=$perlvar{'lonDaemons'};
187: my $fh=IO::File->new(">>$execdir/logs/lonsqlfinal.log");
188: my $now=time;
189: my $local=localtime($now);
190: print $fh "$local ($$): $message\n";
191: }
192:
193:
194:
195: # -------------------------------------------- Return path to profile directory
196:
197: sub propath {
198: my ($udom,$uname)=@_;
199: $udom=~s/\W//g;
200: $uname=~s/\W//g;
201: my $subdir=$uname.'__';
202: $subdir =~ s/(.)(.)(.).*/$1\/$2\/$3/;
203: my $proname="$perlvar{'lonUsersDir'}/$udom/$subdir/$uname";
204: return $proname;
205: }
206:
207: # ------------------------------------------------------------------ Course log
208:
209: sub courselog {
210: my ($path,$command)=@_;
211: return 'not_yet_implemented';
212: }
213:
214: # -------------------------------------------------------------------- User log
215:
216: sub userlog {
217: my ($path,$command)=@_;
218: return 'not_yet_implemented';
219: }
220:
221:
222: # ---------------------------------------------------- Fork once and dissociate
223: $fpid=fork;
224: exit if $fpid;
225: die "Couldn't fork: $!" unless defined ($fpid);
226:
227: POSIX::setsid() or die "Can't start new session: $!";
228:
229: # ------------------------------------------------------- Write our PID on disk
230:
231: $execdir=$perlvar{'lonDaemons'};
232: open (PIDSAVE,">$execdir/logs/lonsql.pid");
233: print PIDSAVE "$$\n";
234: close(PIDSAVE);
235: &logthis("<font color=red>CRITICAL: ---------- Starting ----------</font>");
236:
237: # ----------------------------- Ignore signals generated during initial startup
238: $SIG{HUP}=$SIG{USR1}='IGNORE';
239: # ------------------------------------------------------- Now we are on our own
240: # Fork off our children.
241: for (1 .. $PREFORK) {
242: make_new_child();
243: }
244:
245: # Install signal handlers.
246: $SIG{CHLD} = \&REAPER;
247: $SIG{INT} = $SIG{TERM} = \&HUNTSMAN;
248: $SIG{HUP} = \&HUPSMAN;
249:
250: # And maintain the population.
251: while (1) {
252: sleep; # wait for a signal (i.e., child's death)
253: for ($i = $children; $i < $PREFORK; $i++) {
254: make_new_child(); # top up the child pool
255: }
256: }
257:
258:
259: sub make_new_child {
260: my $pid;
261: my $sigset;
262:
263: # block signal for fork
264: $sigset = POSIX::SigSet->new(SIGINT);
265: sigprocmask(SIG_BLOCK, $sigset)
266: or die "Can't block SIGINT for fork: $!\n";
267:
268: die "fork: $!" unless defined ($pid = fork);
269:
270: if ($pid) {
271: # Parent records the child's birth and returns.
272: sigprocmask(SIG_UNBLOCK, $sigset)
273: or die "Can't unblock SIGINT for fork: $!\n";
274: $children{$pid} = 1;
275: $children++;
276: return;
277: } else {
278: # Child can *not* return from this subroutine.
279: $SIG{INT} = 'DEFAULT'; # make SIGINT kill us as it did before
280:
281: # unblock signals
282: sigprocmask(SIG_UNBLOCK, $sigset)
283: or die "Can't unblock SIGINT for fork: $!\n";
284:
285:
286: #open database handle
287: # making dbh global to avoid garbage collector
288: unless (
289: $dbh = DBI->connect("DBI:mysql:loncapa","www",$perlvar{'lonSqlAccess'},{ RaiseError =>0,PrintError=>0})
290: ) {
291: sleep(10+int(rand(20)));
292: &logthis("<font color=blue>WARNING: Couldn't connect to database ($st secs): $@</font>");
293: print "database handle error\n";
294: exit;
295:
296: };
297: # make sure that a database disconnection occurs with ending kill signals
298: $SIG{TERM}=$SIG{INT}=$SIG{QUIT}=$SIG{__DIE__}=\&DISCONNECT;
299:
300: # handle connections until we've reached $MAX_CLIENTS_PER_CHILD
301: for ($i=0; $i < $MAX_CLIENTS_PER_CHILD; $i++) {
302: $client = $server->accept() or last;
303:
304: # do something with the connection
305: $run = $run+1;
306: my $userinput = <$client>;
307: chomp($userinput);
308:
309: my ($conserver,$query,
310: $arg1,$arg2,$arg3)=split(/&/,$userinput);
311: my $query=unescape($query);
312:
313: #send query id which is pid_unixdatetime_runningcounter
314: $queryid = $thisserver;
315: $queryid .="_".($$)."_";
316: $queryid .= time."_";
317: $queryid .= $run;
318: print $client "$queryid\n";
319:
320: &logthis("QUERY: $query");
321: sleep 1;
322:
323: my $result='';
324:
325: # ---------- At this point, query is received, query-ID assigned and sent back
326: # $query eq 'logquery' will mean that this is a query against log-files
327:
328:
329: if (($query eq 'userlog') || ($query eq 'courselog')) {
330: # ----------------------------------------------------- beginning of log query
331: #
332: # this goes against a user's log file
333: #
334: my $udom=&unescape($arg1);
335: my $uname=&unescape($arg2);
336: my $command=&unescape($arg3);
337: my $path=&propath($udom,$uname);
338: if (-e "$path/activity.log") {
339: if ($query eq 'userlog') {
340: $result=&userlog($path,$command);
341: } else {
342: $result=&courselog($path,$command);
343: }
344: } else {
345: &logthis('Unable to do log query: '.$uname.'@'.$udom);
346: $result='no_such_file';
347: }
348: # ------------------------------------------------------------ end of log query
349: } else {
350: # -------------------------------------------------------- This is an sql query
351: my $custom=unescape($arg1);
352: my $customshow=unescape($arg2);
353: #prepare and execute the query
354: my $sth = $dbh->prepare($query);
355:
356: my @files;
357: my $subsetflag=0;
358: if ($query) {
359: unless ($sth->execute())
360: {
361: &logthis("<font color=blue>WARNING: Could not retrieve from database: $@</font>");
362: $result="";
363: }
364: else {
365: my $r1=$sth->fetchall_arrayref;
366: my @r2;
367: foreach (@$r1) {my $a=$_;
368: my @b=map {escape($_)} @$a;
369: push @files,@{$a}[3];
370: push @r2,join(",", @b)
371: }
372: $result=join("&",@r2);
373: }
374: }
375: # do custom metadata searching here and build into result
376: if ($custom or $customshow) {
377: &logthis("am going to do custom query for $custom");
378: if ($query) {
379: @metalist=map {$perlvar{'lonDocRoot'}.$_.'.meta'} @files;
380: }
381: else {
382: @metalist=(); pop @metalist;
383: opendir(RESOURCES,"$perlvar{'lonDocRoot'}/res/$perlvar{'lonDefDomain'}");
384: my @homeusers=grep
385: {&ishome("$perlvar{'lonDocRoot'}/res/$perlvar{'lonDefDomain'}/$_")}
386: grep {!/^\.\.?$/} readdir(RESOURCES);
387: closedir RESOURCES;
388: foreach my $user (@homeusers) {
389: &find("$perlvar{'lonDocRoot'}/res/$perlvar{'lonDefDomain'}/$user");
390: }
391: }
392: # &logthis("FILELIST:" . join(":::",@metalist));
393: # if file is indicated in sql database and
394: # not part of sql-relevant query, do not pattern match.
395: # if file is not in sql database, output error.
396: # if file is indicated in sql database and is
397: # part of query result list, then do the pattern match.
398: my $customresult='';
399: my @r2;
400: foreach my $m (@metalist) {
401: my $fh=IO::File->new($m);
402: my @lines=<$fh>;
403: my $stuff=join('',@lines);
404: if ($stuff=~/$custom/s) {
405: foreach my $f ('abstract','author','copyright',
406: 'creationdate','keywords','language',
407: 'lastrevisiondate','mime','notes',
408: 'owner','subject','title') {
409: $stuff=~s/\n?\<$f[^\>]*\>.*?<\/$f[^\>]*\>\n?//s;
410: }
411: my $m2=$m; my $docroot=$perlvar{'lonDocRoot'};
412: $m2=~s/^$docroot//;
413: $m2=~s/\.meta$//;
414: unless ($query) {
415: my $q2="select * from metadata where url like binary '$m2'";
416: my $sth = $dbh->prepare($q2);
417: $sth->execute();
418: my $r1=$sth->fetchall_arrayref;
419: foreach (@$r1) {my $a=$_;
420: my @b=map {escape($_)} @$a;
421: push @files,@{$a}[3];
422: push @r2,join(",", @b)
423: }
424: }
425: # &logthis("found: $stuff");
426: $customresult.='&custom='.escape($m2).','.escape($stuff);
427: }
428: }
429: $result=join("&",@r2) unless $query;
430: $result.=$customresult;
431: }
432: # ------------------------------------------------------------ end of sql query
433: }
434: # reply with result, append \n unless already there
435:
436: $result.="\n" unless ($result=~/\n$/);
437: &reply("queryreply:$queryid:$result",$conserver);
438:
439: }
440:
441: # tidy up gracefully and finish
442:
443: #close the database handle
444: $dbh->disconnect
445: or &logthis("<font color=blue>WARNING: Couldn't disconnect from database $DBI::errstr ($st secs): $@</font>");
446:
447: # this exit is VERY important, otherwise the child will become
448: # a producer of more and more children, forking yourself into
449: # process death.
450: exit;
451: }
452: }
453:
454: sub DISCONNECT {
455: $dbh->disconnect or
456: &logthis("<font color=blue>WARNING: Couldn't disconnect from database $DBI::errstr ($st secs): $@</font>");
457: exit;
458: }
459:
460: # -------------------------------------------------- Non-critical communication
461:
462: sub subreply {
463: my ($cmd,$server)=@_;
464: my $peerfile="$perlvar{'lonSockDir'}/$server";
465: my $sclient=IO::Socket::UNIX->new(Peer =>"$peerfile",
466: Type => SOCK_STREAM,
467: Timeout => 10)
468: or return "con_lost";
469: print $sclient "$cmd\n";
470: my $answer=<$sclient>;
471: chomp($answer);
472: if (!$answer) { $answer="con_lost"; }
473: return $answer;
474: }
475:
476: sub reply {
477: my ($cmd,$server)=@_;
478: my $answer;
479: if ($server ne $perlvar{'lonHostID'}) {
480: $answer=subreply($cmd,$server);
481: if ($answer eq 'con_lost') {
482: $answer=subreply("ping",$server);
483: $answer=subreply($cmd,$server);
484: }
485: } else {
486: $answer='self_reply';
487: $answer=subreply($cmd,$server);
488: }
489: return $answer;
490: }
491:
492: # -------------------------------------------------------- Escape Special Chars
493:
494: sub escape {
495: my $str=shift;
496: $str =~ s/(\W)/"%".unpack('H2',$1)/eg;
497: return $str;
498: }
499:
500: # ----------------------------------------------------- Un-Escape Special Chars
501:
502: sub unescape {
503: my $str=shift;
504: $str =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
505: return $str;
506: }
507:
508: # --------------------------------------- Is this the home server of an author?
509: # (copied from lond, modification of the return value)
510: sub ishome {
511: my $author=shift;
512: $author=~s/\/home\/httpd\/html\/res\/([^\/]*)\/([^\/]*).*/$1\/$2/;
513: my ($udom,$uname)=split(/\//,$author);
514: my $proname=propath($udom,$uname);
515: if (-e $proname) {
516: return 1;
517: } else {
518: return 0;
519: }
520: }
521:
522: # -------------------------------------------- Return path to profile directory
523: # (copied from lond)
524: sub propath {
525: my ($udom,$uname)=@_;
526: $udom=~s/\W//g;
527: $uname=~s/\W//g;
528: my $subdir=$uname.'__';
529: $subdir =~ s/(.)(.)(.).*/$1\/$2\/$3/;
530: my $proname="$perlvar{'lonUsersDir'}/$udom/$subdir/$uname";
531: return $proname;
532: }
533:
534: # ----------------------------------- POD (plain old documentation, CPAN style)
535:
536: =head1 NAME
537:
538: lonsql - LON TCP-MySQL-Server Daemon for handling database requests.
539:
540: =head1 SYNOPSIS
541:
542: This script should be run as user=www. The following is an example invocation
543: from the loncron script. Note that a lonsql.pid file contains the pid of
544: the parent process.
545:
546: if (-e $lonsqlfile) {
547: my $lfh=IO::File->new("$lonsqlfile");
548: my $lonsqlpid=<$lfh>;
549: chomp($lonsqlpid);
550: if (kill 0 => $lonsqlpid) {
551: print $fh "<h3>lonsql at pid $lonsqlpid responding</h3>";
552: $restartflag=0;
553: } else {
554: $errors++; $errors++;
555: print $fh "<h3>lonsql at pid $lonsqlpid not responding</h3>";
556: $restartflag=1;
557: print $fh
558: "<h3>Decided to clean up stale .pid file and restart lonsql</h3>";
559: }
560: }
561: if ($restartflag==1) {
562: $errors++;
563: print $fh '<br><font color="red">Killall lonsql: '.
564: system('killall lonsql').' - ';
565: sleep 60;
566: print $fh unlink($lonsqlfile).' - '.
567: system('killall -9 lonsql').
568: '</font><br>';
569: print $fh "<h3>lonsql not running, trying to start</h3>";
570: system(
571: "$perlvar{'lonDaemons'}/lonsql 2>>$perlvar{'lonDaemons'}/logs/lonsql_errors");
572: sleep 10;
573:
574: =head1 DESCRIPTION
575:
576: Not yet written.
577:
578: =head1 README
579:
580: Not yet written.
581:
582: =head1 PREREQUISITES
583:
584: IO::Socket
585: Symbol
586: POSIX
587: IO::Select
588: IO::File
589: Socket
590: Fcntl
591: Tie::RefHash
592: DBI
593:
594: =head1 COREQUISITES
595:
596: =head1 OSNAMES
597:
598: linux
599:
600: =head1 SCRIPT CATEGORIES
601:
602: Server/Process
603:
604: =cut
FreeBSD-CVSweb <freebsd-cvsweb@FreeBSD.org>
![[BACK]](/icons/back.gif){kind=icon}
Return to lonsql CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [LON-CAPA] / loncom