--- loncom/lonsql 2000/05/08 15:14:27 1.1
+++ loncom/lonsql 2004/06/08 22:09:44 1.62
@@ -1,113 +1,596 @@
#!/usr/bin/perl
# The LearningOnline Network
-# lonsql
-# provides unix domain sockets to receive queries from lond and send replies to lonc
+# lonsql - LON TCP-MySQL-Server Daemon for handling database requests.
+#
+# $Id: lonsql,v 1.62 2004/06/08 22:09:44 raeburn Exp $
+#
+# Copyright Michigan State University Board of Trustees
+#
+# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
+#
+# LON-CAPA 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.
+#
+# LON-CAPA 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 LON-CAPA; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+#
+# /home/httpd/html/adm/gpl.txt
+#
+# http://www.lon-capa.org/
#
-# PID in subdir logs/lonc.pid
-# kill kills
-# HUP restarts
-# USR1 tries to open connections again
-
-# 6/4/99,6/5,6/7,6/8,6/9,6/10,6/11,6/12,7/14,7/19,
-# 10/8,10/9,10/15,11/18,12/22,
-# 2/8 Gerd Kortemeyer
-# based on nonforker from Perl Cookbook
-# - server who multiplexes without forking
-use POSIX;
+=pod
+
+=head1 NAME
+
+lonsql - LON TCP-MySQL-Server Daemon for handling database requests.
+
+=head1 SYNOPSIS
+
+This script should be run as user=www.
+Note that a lonsql.pid file contains the pid of the parent process.
+
+=head1 OVERVIEW
+
+=head2 Purpose within LON-CAPA
+
+LON-CAPA is meant to distribute A LOT of educational content to A LOT
+of people. It is ineffective to directly rely on contents within the
+ext2 filesystem to be speedily scanned for on-the-fly searches of
+content descriptions. (Simply put, it takes a cumbersome amount of
+time to open, read, analyze, and close thousands of files.)
+
+The solution is to index various data fields that are descriptive of
+the educational resources on a LON-CAPA server machine in a
+database. Descriptive data fields are referred to as "metadata". The
+question then arises as to how this metadata is handled in terms of
+the rest of the LON-CAPA network without burdening client and daemon
+processes.
+
+The obvious solution, using lonc to send a query to a lond process,
+doesn't work so well in general as you can see in the following
+example:
+
+ lonc= loncapa client process A-lonc= a lonc process on Server A
+ lond= loncapa daemon process
+
+ database command
+ A-lonc --------TCP/IP----------------> B-lond
+
+The problem emerges that A-lonc and B-lond are kept waiting for the
+MySQL server to "do its stuff", or in other words, perform the
+conceivably sophisticated, data-intensive, time-sucking database
+transaction. By tying up a lonc and lond process, this significantly
+cripples the capabilities of LON-CAPA servers.
+
+The solution is to offload the work onto another process, and use
+lonc and lond just for requests and notifications of completed
+processing:
+
+ database command
+
+ A-lonc ---------TCP/IP-----------------> B-lond =====> B-lonsql
+ <---------------------------------/ |
+ "ok, I'll get back to you..." |
+ |
+ /
+ A-lond <------------------------------- B-lonc <======
+ "Guess what? I have the result!"
+
+Of course, depending on success or failure, the messages may vary, but
+the principle remains the same where a separate pool of children
+processes (lonsql's) handle the MySQL database manipulations.
+
+Thus, lonc and lond spend effectively no time waiting on results from
+the database.
+
+=head1 Internals
+
+=over 4
+
+=cut
+
+use strict;
+
+use lib '/home/httpd/lib/perl/';
+use LONCAPA::Configuration;
+use LONCAPA::lonmetadata();
+
use IO::Socket;
+use Symbol;
+use POSIX;
use IO::Select;
use IO::File;
use Socket;
use Fcntl;
use Tie::RefHash;
-use Crypt::IDEA;
use DBI;
+use File::Find;
+use localenroll;
+########################################################
+########################################################
-$childmaxattempts=10;
-$run =0;
-# ------------------------------------ Read httpd access.conf and get variables
-
-open (CONFIG,"/etc/httpd/conf/access.conf") || die "Can't read access.conf";
-
-while ($configline=<CONFIG>) {
- if ($configline =~ /PerlSetVar/) {
- my ($dummy,$varname,$varvalue)=split(/\s+/,$configline);
- chomp($varvalue);
- $perlvar{$varname}=$varvalue;
- }
+=pod
+
+=item Global Variables
+
+=over 4
+
+=item dbh
+
+=back
+
+=cut
+
+########################################################
+########################################################
+my $dbh;
+
+########################################################
+########################################################
+
+=pod
+
+=item Variables required for forking
+
+=over 4
+
+=item $MAX_CLIENTS_PER_CHILD
+
+The number of clients each child should process.
+
+=item %children
+
+The keys to %children are the current child process IDs
+
+=item $children
+
+The current number of children
+
+=back
+
+=cut
+
+########################################################
+########################################################
+my $MAX_CLIENTS_PER_CHILD = 5; # number of clients each child should process
+my %children = (); # keys are current child process IDs
+my $children = 0; # current number of children
+
+###################################################################
+###################################################################
+
+=pod
+
+=item Main body of code.
+
+=over 4
+
+=item Read data from loncapa_apache.conf and loncapa.conf.
+
+=item Ensure we can access the database.
+
+=item Determine if there are other instances of lonsql running.
+
+=item Read the hosts file.
+
+=item Create a socket for lonsql.
+
+=item Fork once and dissociate from parent.
+
+=item Write PID to disk.
+
+=item Prefork children and maintain the population of children.
+
+=back
+
+=cut
+
+###################################################################
+###################################################################
+my $childmaxattempts=10;
+my $run =0; # running counter to generate the query-id
+#
+# Read loncapa_apache.conf and loncapa.conf
+#
+my $perlvarref=LONCAPA::Configuration::read_conf('loncapa.conf');
+my %perlvar=%{$perlvarref};
+#
+# Make sure that database can be accessed
+#
+my $dbh;
+unless ($dbh = DBI->connect("DBI:mysql:loncapa","www",
+ $perlvar{'lonSqlAccess'},
+ { RaiseError =>0,PrintError=>0})) {
+ print "Cannot connect to database!\n";
+ my $emailto="$perlvar{'lonAdmEMail'},$perlvar{'lonSysEMail'}";
+ my $subj="LON: $perlvar{'lonHostID'} Cannot connect to database!";
+ system("echo 'Cannot connect to MySQL database!' |".
+ " mailto $emailto -s '$subj' > /dev/null");
+
+ open(SMP,'>/home/httpd/html/lon-status/mysql.txt');
+ print SMP 'time='.time.'&mysql=defunct'."\n";
+ close(SMP);
+
+ exit 1;
+} else {
+ $dbh->disconnect;
}
-close(CONFIG);
-# ------------------------------------------------------------- Read hosts file
-#$PREFORK=4; # number of children to maintain, at least four spare
+#
+# Check if other instance running
+#
+my $pidfile="$perlvar{'lonDaemons'}/logs/lonsql.pid";
+if (-e $pidfile) {
+ my $lfh=IO::File->new("$pidfile");
+ my $pide=<$lfh>;
+ chomp($pide);
+ if (kill 0 => $pide) { die "already running"; }
+}
+#
+# Read hosts file
+#
+my %hostip;
+my $thisserver;
+my $PREFORK=4; # number of children to maintain, at least four spare
open (CONFIG,"$perlvar{'lonTabDir'}/hosts.tab") || die "Can't read host file";
-
-while ($configline=<CONFIG>) {
+while (my $configline=<CONFIG>) {
my ($id,$domain,$role,$name,$ip)=split(/:/,$configline);
chomp($ip);
+ $hostip{$ip}=$id;
+ $thisserver=$name if ($id eq $perlvar{'lonHostID'});
+ $PREFORK++;
+}
+close(CONFIG);
+#
+$PREFORK=int($PREFORK/4);
+
+#
+# Create a socket to talk to lond
+#
+my $unixsock = "mysqlsock";
+my $localfile="$perlvar{'lonSockDir'}/$unixsock";
+my $server;
+unlink ($localfile);
+unless ($server=IO::Socket::UNIX->new(Local =>"$localfile",
+ Type => SOCK_STREAM,
+ Listen => 10)) {
+ print "in socket error:$@\n";
+}
- #$hostip{$ip}=$id;
- $hostip{$id}=$ip;
+#
+# Fork once and dissociate
+#
+my $fpid=fork;
+exit if $fpid;
+die "Couldn't fork: $!" unless defined ($fpid);
+POSIX::setsid() or die "Can't start new session: $!";
- if ($id eq $perlvar{'lonHostID'}) { $thisserver=$name; }
+#
+# Write our PID on disk
+my $execdir=$perlvar{'lonDaemons'};
+open (PIDSAVE,">$execdir/logs/lonsql.pid");
+print PIDSAVE "$$\n";
+close(PIDSAVE);
+&logthis("<font color='red'>CRITICAL: ---------- Starting ----------</font>");
- #$PREFORK++;
+#
+# Ignore signals generated during initial startup
+$SIG{HUP}=$SIG{USR1}='IGNORE';
+# Now we are on our own
+# Fork off our children.
+for (1 .. $PREFORK) {
+ make_new_child();
}
-close(CONFIG);
+#
+# Install signal handlers.
+$SIG{CHLD} = \&REAPER;
+$SIG{INT} = $SIG{TERM} = \&HUNTSMAN;
+$SIG{HUP} = \&HUPSMAN;
-# -------------------------------------------------------- Routines for forking
-# global variables
-#$MAX_CLIENTS_PER_CHILD = 5; # number of clients each child should process
-%children = (); # keys are current child process IDs
-#$children = 0; # current number of children
-%childpid = (); # the other way around
+#
+# And maintain the population.
+while (1) {
+ sleep; # wait for a signal (i.e., child's death)
+ for (my $i = $children; $i < $PREFORK; $i++) {
+ make_new_child(); # top up the child pool
+ }
+}
-%childatt = (); # number of attempts to start server
- # for ID
+########################################################
+########################################################
+=pod
-sub REAPER { # takes care of dead children
- $SIG{CHLD} = \&REAPER;
- my $pid = wait;
+=item &make_new_child
- #$children --;
- #&logthis("Child $pid died");
- #delete $children{$pid};
-
- my $wasserver=$children{$pid};
- &logthis("<font color=red>CRITICAL: "
- ."Child $pid for server $wasserver died ($childatt{$wasserver})</font>");
- delete $children{$pid};
- delete $childpid{$wasserver};
- my $port = "$perlvar{'lonSockDir'}/$wasserver";
- unlink($port);
+Inputs: None
+Returns: None
-}
+=cut
-sub HUNTSMAN { # signal handler for SIGINT
- local($SIG{CHLD}) = 'IGNORE'; # we're going to kill our children
- kill 'INT' => keys %children;
- my $execdir=$perlvar{'lonDaemons'};
- unlink("$execdir/logs/lonsql.pid");
- &logthis("<font color=red>CRITICAL: Shutting down</font>");
- exit; # clean up with dignity
+########################################################
+########################################################
+sub make_new_child {
+ my $pid;
+ my $sigset;
+ #
+ # block signal for fork
+ $sigset = POSIX::SigSet->new(SIGINT);
+ sigprocmask(SIG_BLOCK, $sigset)
+ or die "Can't block SIGINT for fork: $!\n";
+ #
+ die "fork: $!" unless defined ($pid = fork);
+ #
+ if ($pid) {
+ # Parent records the child's birth and returns.
+ sigprocmask(SIG_UNBLOCK, $sigset)
+ or die "Can't unblock SIGINT for fork: $!\n";
+ $children{$pid} = 1;
+ $children++;
+ return;
+ } else {
+ # Child can *not* return from this subroutine.
+ $SIG{INT} = 'DEFAULT'; # make SIGINT kill us as it did before
+ # unblock signals
+ sigprocmask(SIG_UNBLOCK, $sigset)
+ or die "Can't unblock SIGINT for fork: $!\n";
+ #open database handle
+ # making dbh global to avoid garbage collector
+ unless ($dbh = DBI->connect("DBI:mysql:loncapa","www",
+ $perlvar{'lonSqlAccess'},
+ { RaiseError =>0,PrintError=>0})) {
+ sleep(10+int(rand(20)));
+ &logthis("<font color='blue'>WARNING: Couldn't connect to database".
+ ": $@</font>");
+ # "($st secs): $@</font>");
+ print "database handle error\n";
+ exit;
+ }
+ # make sure that a database disconnection occurs with
+ # ending kill signals
+ $SIG{TERM}=$SIG{INT}=$SIG{QUIT}=$SIG{__DIE__}=\&DISCONNECT;
+ # handle connections until we've reached $MAX_CLIENTS_PER_CHILD
+ for (my $i=0; $i < $MAX_CLIENTS_PER_CHILD; $i++) {
+ my $client = $server->accept() or last;
+ # do something with the connection
+ $run = $run+1;
+ my $userinput = <$client>;
+ chomp($userinput);
+ #
+ my ($conserver,$query,
+ $arg1,$arg2,$arg3)=split(/&/,$userinput);
+ my $query=unescape($query);
+ #
+ #send query id which is pid_unixdatetime_runningcounter
+ my $queryid = $thisserver;
+ $queryid .="_".($$)."_";
+ $queryid .= time."_";
+ $queryid .= $run;
+ print $client "$queryid\n";
+ #
+ # &logthis("QUERY: $query - $arg1 - $arg2 - $arg3");
+ sleep 1;
+ #
+ my $result='';
+ #
+ # At this point, query is received, query-ID assigned and sent
+ # back, $query eq 'logquery' will mean that this is a query
+ # against log-files
+ if (($query eq 'userlog') || ($query eq 'courselog')) {
+ # beginning of log query
+ my $udom = &unescape($arg1);
+ my $uname = &unescape($arg2);
+ my $command = &unescape($arg3);
+ my $path = &propath($udom,$uname);
+ if (-e "$path/activity.log") {
+ if ($query eq 'userlog') {
+ $result=&userlog($path,$command);
+ } else {
+ $result=&courselog($path,$command);
+ }
+ } else {
+ &logthis('Unable to do log query: '.$uname.'@'.$udom);
+ $result='no_such_file';
+ }
+ # end of log query
+ } elsif ($query eq 'fetchenrollment') {
+ # retrieve institutional class lists
+ my $dom = &unescape($arg1);
+ my %affiliates = ();
+ my %replies = ();
+ my $locresult = '';
+ my $querystr = &unescape($arg3);
+ foreach (split/%%/,$querystr) {
+ if (/^(\w+)=([^=]+)$/) {
+ @{$affiliates{$1}} = split/,/,$2;
+ }
+ }
+ $locresult = &localenroll::fetch_enrollment($dom,\%affiliates,\%replies);
+ $result = &escape($locresult.':');
+ if ($locresult) {
+ $result .= &escape(join(':',map{$_.'='.$replies{$_}} keys %replies));
+ }
+ } else {
+ # Do an sql query
+ $result = &do_sql_query($query,$arg1,$arg2);
+ }
+ # result does not need to be escaped because it has already been
+ # escaped.
+ #$result=&escape($result);
+ &reply("queryreply:$queryid:$result",$conserver);
+ }
+ # tidy up gracefully and finish
+ #
+ # close the database handle
+ $dbh->disconnect
+ or &logthis("<font color='blue'>WARNING: Couldn't disconnect".
+ " from database $DBI::errstr : $@</font>");
+ # this exit is VERY important, otherwise the child will become
+ # a producer of more and more children, forking yourself into
+ # process death.
+ exit;
+ }
}
-sub HUPSMAN { # signal handler for SIGHUP
- local($SIG{CHLD}) = 'IGNORE'; # we're going to kill our children
- kill 'INT' => keys %children;
- close($server); # free up socket
- &logthis("<font color=red>CRITICAL: Restarting</font>");
- my $execdir=$perlvar{'lonDaemons'};
- exec("$execdir/lonsql"); # here we go again
+########################################################
+########################################################
+
+=pod
+
+=item &do_sql_query
+
+Runs an sql metadata table query.
+
+Inputs: $query, $custom, $customshow
+
+Returns: A string containing escaped results.
+
+=cut
+
+########################################################
+########################################################
+{
+ my @metalist;
+
+sub process_file {
+ if ( -e $_ && # file exists
+ -f $_ && # and is a normal file
+ /\.meta$/ && # ends in meta
+ ! /^.+\.\d+\.[^\.]+\.meta$/ # is not a previous version
+ ) {
+ push(@metalist,$File::Find::name);
+ }
}
+sub do_sql_query {
+ my ($query,$custom,$customshow) = @_;
+ $custom = &unescape($custom);
+ $customshow = &unescape($customshow);
+ #
+ @metalist = ();
+ #
+ my $result = '';
+ my @results = ();
+ my @files;
+ my $subsetflag=0;
+ #
+ if ($query) {
+ #prepare and execute the query
+ my $sth = $dbh->prepare($query);
+ unless ($sth->execute()) {
+ &logthis('<font color="blue">'.
+ 'WARNING: Could not retrieve from database:'.
+ $sth->errstr().'</font>');
+ } else {
+ my $aref=$sth->fetchall_arrayref;
+ foreach my $row (@$aref) {
+ push @files,@{$row}[3] if ($custom or $customshow);
+ my @b=map { &escape($_); } @$row;
+ push @results,join(",", @b);
+ # Build up the @files array with the LON-CAPA urls
+ # of the resources.
+ }
+ }
+ }
+ # do custom metadata searching here and build into result
+ return join("&",@results) if (! ($custom or $customshow));
+ # Only get here if there is a custom query or custom show request
+ &logthis("Doing custom query for $custom");
+ if ($query) {
+ @metalist=map {
+ $perlvar{'lonDocRoot'}.$_.'.meta';
+ } @files;
+ } else {
+ my $dir = "$perlvar{'lonDocRoot'}/res/$perlvar{'lonDefDomain'}";
+ @metalist=();
+ opendir(RESOURCES,$dir);
+ my @homeusers=grep {
+ &ishome($dir.'/'.$_);
+ } grep {!/^\.\.?$/} readdir(RESOURCES);
+ closedir RESOURCES;
+ # Define the
+ foreach my $user (@homeusers) {
+ find (\&process_file,$dir.'/'.$user);
+ }
+ }
+ # if file is indicated in sql database and
+ # not part of sql-relevant query, do not pattern match.
+ #
+ # if file is not in sql database, output error.
+ #
+ # if file is indicated in sql database and is
+ # part of query result list, then do the pattern match.
+ my $customresult='';
+ my @results;
+ foreach my $metafile (@metalist) {
+ my $fh=IO::File->new($metafile);
+ my @lines=<$fh>;
+ my $stuff=join('',@lines);
+ if ($stuff=~/$custom/s) {
+ foreach my $f ('abstract','author','copyright',
+ 'creationdate','keywords','language',
+ 'lastrevisiondate','mime','notes',
+ 'owner','subject','title') {
+ $stuff=~s/\n?\<$f[^\>]*\>.*?<\/$f[^\>]*\>\n?//s;
+ }
+ my $mfile=$metafile;
+ my $docroot=$perlvar{'lonDocRoot'};
+ $mfile=~s/^$docroot//;
+ $mfile=~s/\.meta$//;
+ unless ($query) {
+ my $q2="SELECT * FROM metadata WHERE url ".
+ " LIKE BINARY '?'";
+ my $sth = $dbh->prepare($q2);
+ $sth->execute($mfile);
+ my $aref=$sth->fetchall_arrayref;
+ foreach my $a (@$aref) {
+ my @b=map { &escape($_)} @$a;
+ push @results,join(",", @b);
+ }
+ }
+ # &logthis("found: $stuff");
+ $customresult.='&custom='.&escape($mfile).','.
+ escape($stuff);
+ }
+ }
+ $result=join("&",@results) unless $query;
+ $result.=$customresult;
+ #
+ return $result;
+} # End of &do_sql_query
+
+} # End of scoping curly braces for &process_file and &do_sql_query
+########################################################
+########################################################
+
+=pod
+
+=item &logthis
+
+Inputs: $message, the message to log
+
+Returns: nothing
+
+Writes $message to the logfile.
+
+=cut
+
+########################################################
+########################################################
sub logthis {
my $message=shift;
my $execdir=$perlvar{'lonDaemons'};
@@ -117,35 +600,25 @@ sub logthis {
print $fh "$local ($$): $message\n";
}
-# ----------------------------------------------------------- Send USR1 to lonc
-sub reconlonc {
- my $peerfile=shift;
- &logthis("Trying to reconnect for $peerfile");
- my $loncfile="$perlvar{'lonDaemons'}/logs/lonc.pid";
- if (my $fh=IO::File->new("$loncfile")) {
- my $loncpid=<$fh>;
- chomp($loncpid);
- if (kill 0 => $loncpid) {
- &logthis("lonc at pid $loncpid responding, sending USR1");
- kill USR1 => $loncpid;
- sleep 1;
- if (-e "$peerfile") { return; }
- &logthis("$peerfile still not there, give it another try");
- sleep 5;
- if (-e "$peerfile") { return; }
- &logthis(
- "<font color=blue>WARNING: $peerfile still not there, giving up</font>");
- } else {
- &logthis(
- "<font color=red>CRITICAL: "
- ."lonc at pid $loncpid not responding, giving up</font>");
- }
- } else {
- &logthis('<font color=red>CRITICAL: lonc not running, giving up</font>');
- }
-}
-
# -------------------------------------------------- Non-critical communication
+
+########################################################
+########################################################
+
+=pod
+
+=item &subreply
+
+Sends a command to a server. Called only by &reply.
+
+Inputs: $cmd,$server
+
+Returns: The results of the message or 'con_lost' on error.
+
+=cut
+
+########################################################
+########################################################
sub subreply {
my ($cmd,$server)=@_;
my $peerfile="$perlvar{'lonSockDir'}/$server";
@@ -156,10 +629,27 @@ sub subreply {
print $sclient "$cmd\n";
my $answer=<$sclient>;
chomp($answer);
- if (!$answer) { $answer="con_lost"; }
+ $answer="con_lost" if (!$answer);
return $answer;
}
+########################################################
+########################################################
+
+=pod
+
+=item &reply
+
+Sends a command to a server.
+
+Inputs: $cmd,$server
+
+Returns: The results of the message or 'con_lost' on error.
+
+=cut
+
+########################################################
+########################################################
sub reply {
my ($cmd,$server)=@_;
my $answer;
@@ -167,176 +657,304 @@ sub reply {
$answer=subreply($cmd,$server);
if ($answer eq 'con_lost') {
$answer=subreply("ping",$server);
- if ($answer ne $server) {
- &reconlonc("$perlvar{'lonSockDir'}/$server");
- }
$answer=subreply($cmd,$server);
}
} else {
$answer='self_reply';
+ $answer=subreply($cmd,$server);
}
return $answer;
}
-$unixsock = "msua1_sql";
-my $localfile="$perlvar{'lonSockDir'}/$unixsock";
-my $server=IO::Socket::UNIX->new(LocalAddr =>"$localfile",
- Type => SOCK_STREAM,
- Timeout => 10);
+########################################################
+########################################################
-# ---------------------------------------------------- Fork once and dissociate
-$fpid=fork;
-exit if $fpid;
-die "Couldn't fork: $!" unless defined ($fpid);
+=pod
-POSIX::setsid() or die "Can't start new session: $!";
+=item &escape
-# ------------------------------------------------------- Write our PID on disk
+Escape special characters in a string.
-$execdir=$perlvar{'lonDaemons'};
-open (PIDSAVE,">$execdir/logs/lonsql.pid");
-print PIDSAVE "$$\n";
-close(PIDSAVE);
-&logthis("<font color=red>CRITICAL: ---------- Starting ----------</font>");
+Inputs: string to escape
-# ----------------------------- Ignore signals generated during initial startup
-$SIG{HUP}=$SIG{USR1}='IGNORE';
+Returns: The input string with special characters escaped.
+
+=cut
+
+########################################################
+########################################################
+sub escape {
+ my $str=shift;
+ $str =~ s/(\W)/"%".unpack('H2',$1)/eg;
+ return $str;
+}
+
+########################################################
+########################################################
+
+=pod
-# ------------------------------------------------------- Now we are on our own
-#Fork of children one for every server
+=item &unescape
-#for (1 .. $PREFORK) {
-# make_new_child($thisserver);
-#}
+Unescape special characters in a string.
-foreach $thisserver (keys %hostip) {
- make_new_child($thisserver);
+Inputs: string to unescape
+
+Returns: The input string with special characters unescaped.
+
+=cut
+
+########################################################
+########################################################
+sub unescape {
+ my $str=shift;
+ $str =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
+ return $str;
}
-&logthis("Done starting initial servers");
-# ----------------------------------------------------- Install signal handlers
+########################################################
+########################################################
-$SIG{CHLD} = \&REAPER;
-$SIG{INT} = $SIG{TERM} = \&HUNTSMAN;
-$SIG{HUP} = \&HUPSMAN;
+=pod
-# And maintain the population.
-while (1) {
- sleep; # wait for a signal (i.e., child's death)
+=item &ishome
+
+Determine if the current machine is the home server for a user.
+The determination is made by checking the filesystem for the users information.
- #for ($i = $children; $i < $PREFORK; $i++) {
- # make_new_child(); # top up the child pool
- #}
-
- foreach $thisserver (keys %hostip) {
- if (!$childpid{$thisserver}) {
- if ($childatt{$thisserver}<=$childmaxattempts) {
- $childatt{$thisserver}++;
- &logthis(
- "<font color=yellow>INFO: Trying to reconnect for $thisserver "
- ."($childatt{$thisserver} of $childmaxattempts attempts)</font>");
- make_new_child($thisserver);
- }
- }
+Inputs: $author
+
+Returns: 0 - this is not the authors home server, 1 - this is.
+
+=cut
+
+########################################################
+########################################################
+sub ishome {
+ my $author=shift;
+ $author=~s/\/home\/httpd\/html\/res\/([^\/]*)\/([^\/]*).*/$1\/$2/;
+ my ($udom,$uname)=split(/\//,$author);
+ my $proname=propath($udom,$uname);
+ if (-e $proname) {
+ return 1;
+ } else {
+ return 0;
}
}
-sub make_new_child {
- my $conserver=shift;
- my $pid;
- my $sigset;
- my $queryid;
+########################################################
+########################################################
- &logthis("Attempting to start child");
- # block signal for fork
- $sigset = POSIX::SigSet->new(SIGINT);
- sigprocmask(SIG_BLOCK, $sigset)
- or die "Can't block SIGINT for fork: $!\n";
-
- die "fork: $!" unless defined ($pid = fork);#do the forking of children
-
- if ($pid) {
- # Parent records the child's birth and returns.
- sigprocmask(SIG_UNBLOCK, $sigset)
- or die "Can't unblock SIGINT for fork: $!\n";
- $children{$pid} = 1;
- $children++;
- return;
- } else {
- # Child can *not* return from this subroutine.
- $SIG{INT} = 'DEFAULT'; # make SIGINT kill us as it did before
-
- # unblock signals
- sigprocmask(SIG_UNBLOCK, $sigset)
- or die "Can't unblock SIGINT for fork: $!\n";
+=pod
- #connect to the database
- unless (
- my $dbh = DBI->connect("DBI:mysql:loncapa","root","mysql",{ RaiseError =>1,})
- ) {
- my $st=120+int(rand(240));
- &logthis("<font color=blue>WARNING: Couldn't connect to database ($st secs): $@</font>");
- sleep($st);
- exit;#do I need to cleanup before exit if can't connect to database
- };
-
- # handle connections until we've reached $MAX_CLIENTS_PER_CHILD
- for ($i=0; $i < $MAX_CLIENTS_PER_CHILD; $i++) {
- $client = $server->accept() or last;
- $run = $run+1;
-# =============================================================================
- # do something with the connection
-# -----------------------------------------------------------------------------
- my $userinput = "1";
- #while (my $userinput=<$client>) {
- while (my $userinput="1") {
- print ("here we go\n");
- chomp($userinput);
-
- #send query id which is pid_unixdatetime_runningcounter
- $queryid = $conserver;
- $queryid .=($$)."_";
- $queryid .= time."_";
- $queryid .= run;
- print $client "$queryid\n";
-
- #prepare and execute the query
-
- my $sth = $dbh->prepare("select * into outfile \"$queryid\" from resource");#can't use $userinput directly since we the query to write to a file which depends on the query id generated
-
- $sth->execute();
- if (-e "$queryid") { print "Oops ,file is already there!\n";}
- else
- {
- print "error reading into file\n";
- }
-
- #connect to lonc and send the query results
- $reply = reply($queryid,$conserver);
-
- }
-# =============================================================================
+=item &propath
+
+Inputs: user name, user domain
+
+Returns: The full path to the users directory.
+
+=cut
+
+########################################################
+########################################################
+sub propath {
+ my ($udom,$uname)=@_;
+ $udom=~s/\W//g;
+ $uname=~s/\W//g;
+ my $subdir=$uname.'__';
+ $subdir =~ s/(.)(.)(.).*/$1\/$2\/$3/;
+ my $proname="$perlvar{'lonUsersDir'}/$udom/$subdir/$uname";
+ return $proname;
+}
+
+########################################################
+########################################################
+
+=pod
+
+=item &courselog
+
+Inputs: $path, $command
+
+Returns: unescaped string of values.
+
+=cut
+
+########################################################
+########################################################
+sub courselog {
+ my ($path,$command)=@_;
+ my %filters=();
+ foreach (split(/\:/,&unescape($command))) {
+ my ($name,$value)=split(/\=/,$_);
+ $filters{$name}=$value;
+ }
+ my @results=();
+ open(IN,$path.'/activity.log') or return ('file_error');
+ while (my $line=<IN>) {
+ chomp($line);
+ my ($timestamp,$host,$log)=split(/\:/,$line);
+#
+# $log has the actual log entries; currently still escaped, and
+# %26(timestamp)%3a(url)%3a(user)%3a(domain)
+# then additionally
+# %3aPOST%3a(name)%3d(value)%3a(name)%3d(value)
+# or
+# %3aCSTORE%3a(name)%3d(value)%26(name)%3d(value)
+#
+# get delimiter between timestamped entries to be &&&
+ $log=~s/\%26(\d+)\%3a/\&\&\&$1\%3a/g;
+# now go over all log entries
+ foreach (split(/\&\&\&/,&unescape($log))) {
+ my ($time,$res,$uname,$udom,$action,@values)=split(/\:/,$_);
+ my $values=&unescape(join(':',@values));
+ $values=~s/\&/\:/g;
+ $res=&unescape($res);
+ my $include=1;
+ if (($filters{'username'}) && ($uname ne $filters{'username'}))
+ { $include=0; }
+ if (($filters{'domain'}) && ($udom ne $filters{'domain'}))
+ { $include=0; }
+ if (($filters{'url'}) && ($res!~/$filters{'url'}/))
+ { $include=0; }
+ if (($filters{'start'}) && ($time<$filters{'start'}))
+ { $include=0; }
+ if (($filters{'end'}) && ($time>$filters{'end'}))
+ { $include=0; }
+ if (($filters{'action'} eq 'view') && ($action))
+ { $include=0; }
+ if (($filters{'action'} eq 'submit') && ($action ne 'POST'))
+ { $include=0; }
+ if (($filters{'action'} eq 'grade') && ($action ne 'CSTORE'))
+ { $include=0; }
+ if ($include) {
+ push(@results,($time<1000000000?'0':'').$time.':'.$res.':'.
+ $uname.':'.$udom.':'.
+ $action.':'.$values);
+ }
+ }
+ }
+ close IN;
+ return join('&',sort(@results));
+}
+
+########################################################
+########################################################
+
+=pod
+
+=item &userlog
+
+Inputs: $path, $command
+
+Returns: unescaped string of values.
+
+=cut
+
+########################################################
+########################################################
+sub userlog {
+ my ($path,$command)=@_;
+ my %filters=();
+ foreach (split(/\:/,&unescape($command))) {
+ my ($name,$value)=split(/\=/,$_);
+ $filters{$name}=$value;
+ }
+ my @results=();
+ open(IN,$path.'/activity.log') or return ('file_error');
+ while (my $line=<IN>) {
+ chomp($line);
+ my ($timestamp,$host,$log)=split(/\:/,$line);
+ $log=&unescape($log);
+ my $include=1;
+ if (($filters{'start'}) && ($timestamp<$filters{'start'}))
+ { $include=0; }
+ if (($filters{'end'}) && ($timestamp>$filters{'end'}))
+ { $include=0; }
+ if (($filters{'action'} eq 'log') && ($log!~/^Log/)) { $include=0; }
+ if (($filters{'action'} eq 'check') && ($log!~/^Check/))
+ { $include=0; }
+ if ($include) {
+ push(@results,$timestamp.':'.$log);
}
-
- # tidy up gracefully and finish
-
- # this exit is VERY important, otherwise the child will become
- # a producer of more and more children, forking yourself into
- # process death.
- exit;
}
-}
-
+ close IN;
+ return join('&',sort(@results));
+}
+
+########################################################
+########################################################
+
+=pod
-
+=item Functions required for forking
+=over 4
+=item REAPER
+REAPER takes care of dead children.
+=item HUNTSMAN
+Signal handler for SIGINT.
+=item HUPSMAN
+
+Signal handler for SIGHUP
+
+=item DISCONNECT
+
+Disconnects from database.
+
+=back
+
+=cut
+
+########################################################
+########################################################
+sub REAPER { # takes care of dead children
+ $SIG{CHLD} = \&REAPER;
+ my $pid = wait;
+ $children --;
+ &logthis("Child $pid died");
+ delete $children{$pid};
+}
+sub HUNTSMAN { # signal handler for SIGINT
+ local($SIG{CHLD}) = 'IGNORE'; # we're going to kill our children
+ kill 'INT' => keys %children;
+ my $execdir=$perlvar{'lonDaemons'};
+ unlink("$execdir/logs/lonsql.pid");
+ &logthis("<font color='red'>CRITICAL: Shutting down</font>");
+ $unixsock = "mysqlsock";
+ my $port="$perlvar{'lonSockDir'}/$unixsock";
+ unlink($port);
+ exit; # clean up with dignity
+}
+
+sub HUPSMAN { # signal handler for SIGHUP
+ local($SIG{CHLD}) = 'IGNORE'; # we're going to kill our children
+ kill 'INT' => keys %children;
+ close($server); # free up socket
+ &logthis("<font color='red'>CRITICAL: Restarting</font>");
+ my $execdir=$perlvar{'lonDaemons'};
+ $unixsock = "mysqlsock";
+ my $port="$perlvar{'lonSockDir'}/$unixsock";
+ unlink($port);
+ exec("$execdir/lonsql"); # here we go again
+}
+
+sub DISCONNECT {
+ $dbh->disconnect or
+ &logthis("<font color='blue'>WARNING: Couldn't disconnect from database ".
+ " $DBI::errstr : $@</font>");
+ exit;
+}
+=pod
+=back
+=cut