--- loncom/lonsql 2001/03/22 19:25:52 1.10
+++ loncom/lonsql 2004/05/11 21:08:20 1.60
@@ -1,8 +1,110 @@
#!/usr/bin/perl
-# lonsql-based on the preforker:harsha jagasia:date:5/10/00
-# 7/25 Gerd Kortemeyer
-# many different dates Scott Harrison
-# 03/22/2001 Scott Harrison
+
+# The LearningOnline Network
+# lonsql - LON TCP-MySQL-Server Daemon for handling database requests.
+#
+# $Id: lonsql,v 1.60 2004/05/11 21:08:20 matthew 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/
+#
+
+=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;
@@ -12,37 +114,122 @@ use Socket;
use Fcntl;
use Tie::RefHash;
use DBI;
+use File::Find;
-my @metalist;
-# ----------------- Code to enable 'find' subroutine listing of the .meta files
-require "find.pl";
-sub wanted {
- (($dev,$ino,$mode,$nlink,$uid,$gid) = lstat($_)) &&
- -f _ &&
- /^.*\.meta$/ &&
- push(@metalist,"$dir/$_");
-}
+########################################################
+########################################################
+=pod
-$childmaxattempts=10;
-$run =0;#running counter to generate the query-id
-
-# ------------------------------------ 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;
- }
-}
-close(CONFIG);
+=item Global Variables
-# --------------------------------------------- Check if other instance running
+=over 4
-my $pidfile="$perlvar{'lonDaemons'}/logs/lonsql.pid";
+=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;
+}
+
+#
+# Check if other instance running
+#
+my $pidfile="$perlvar{'lonDaemons'}/logs/lonsql.pid";
if (-e $pidfile) {
my $lfh=IO::File->new("$pidfile");
my $pide=<$lfh>;
@@ -50,128 +237,103 @@ if (-e $pidfile) {
if (kill 0 => $pide) { die "already running"; }
}
-# ------------------------------------------------------------- Read hosts file
-$PREFORK=4; # number of children to maintain, at least four spare
-
+#
+# 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}=$id;
-
- if ($id eq $perlvar{'lonHostID'}) { $thisserver=$name; }
-
+ $thisserver=$name if ($id eq $perlvar{'lonHostID'});
$PREFORK++;
}
close(CONFIG);
+#
+$PREFORK=int($PREFORK/4);
-$unixsock = "mysqlsock";
+#
+# 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))
-{
+ Type => SOCK_STREAM,
+ Listen => 10)) {
print "in socket error:$@\n";
}
-# -------------------------------------------------------- Routines for forking
-# global variables
-$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
-
-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 logthis {
- my $message=shift;
- my $execdir=$perlvar{'lonDaemons'};
- my $fh=IO::File->new(">>$execdir/logs/lonsqlfinal.log");
- my $now=time;
- my $local=localtime($now);
- print $fh "$local ($$): $message\n";
-}
-# ---------------------------------------------------- Fork once and dissociate
-$fpid=fork;
+#
+# Fork once and dissociate
+#
+my $fpid=fork;
exit if $fpid;
die "Couldn't fork: $!" unless defined ($fpid);
-
POSIX::setsid() or die "Can't start new session: $!";
-# ------------------------------------------------------- Write our PID on disk
-
-$execdir=$perlvar{'lonDaemons'};
+#
+# Write our PID on disk
+my $execdir=$perlvar{'lonDaemons'};
open (PIDSAVE,">$execdir/logs/lonsql.pid");
print PIDSAVE "$$\n";
close(PIDSAVE);
-&logthis("<font color=red>CRITICAL: ---------- Starting ----------</font>");
+&logthis("<font color='red'>CRITICAL: ---------- Starting ----------</font>");
-# ----------------------------- Ignore signals generated during initial startup
+#
+# Ignore signals generated during initial startup
$SIG{HUP}=$SIG{USR1}='IGNORE';
-# ------------------------------------------------------- Now we are on our own
-# Fork off our children.
+# Now we are on our own
+# Fork off our children.
for (1 .. $PREFORK) {
make_new_child();
}
+#
# Install signal handlers.
$SIG{CHLD} = \&REAPER;
$SIG{INT} = $SIG{TERM} = \&HUNTSMAN;
$SIG{HUP} = \&HUPSMAN;
+#
# And maintain the population.
while (1) {
sleep; # wait for a signal (i.e., child's death)
- for ($i = $children; $i < $PREFORK; $i++) {
+ for (my $i = $children; $i < $PREFORK; $i++) {
make_new_child(); # top up the child pool
}
}
+########################################################
+########################################################
+
+=pod
+=item &make_new_child
+
+Inputs: None
+
+Returns: None
+
+=cut
+
+########################################################
+########################################################
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)
@@ -182,84 +344,83 @@ sub make_new_child {
} 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","123",{ RaiseError =>0,PrintError=>0})
- ) {
- my $st=120+int(rand(240));
- &logthis("<font color=blue>WARNING: Couldn't connect to database ($st secs): $@</font>");
- print "database handle error\n";
- sleep($st);
- exit;
-
- };
- # make sure that a database disconnection occurs with ending kill signals
+ 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 $MAX_CLIENTS_PER_CHILD
- for ($i=0; $i < $MAX_CLIENTS_PER_CHILD; $i++) {
- $client = $server->accept() or last;
-
+ 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,$querytmp,$customtmp)=split(/&/,$userinput);
- my $query=unescape($querytmp);
- my $custom=unescape($customtmp);
-
+ #
+ my ($conserver,$query,
+ $arg1,$arg2,$arg3)=split(/&/,$userinput);
+ my $query=unescape($query);
+ #
#send query id which is pid_unixdatetime_runningcounter
- $queryid = $thisserver;
+ my $queryid = $thisserver;
$queryid .="_".($$)."_";
$queryid .= time."_";
$queryid .= $run;
print $client "$queryid\n";
-
- #prepare and execute the query
- my $sth = $dbh->prepare($query);
- my $result;
- unless ($sth->execute())
- {
- &logthis("<font color=blue>WARNING: Could not retrieve from database: $@</font>");
- $result="";
- }
- else {
- my $r1=$sth->fetchall_arrayref;
- my @r2; map {my $a=$_; my @b=map {escape($_)} @$a; push @r2,join(",", @b)} (@$r1);
- $result=join("&",@r2) . "\n";
- }
-
- # do custom metadata searching here and build into result
- if ($custom) {
- &logthis("am going to do custom query for $custom");
- @metalist=(); pop @metalist;
- &find("$perlvar{'lonDocRoot'}/res");
- &logthis("FILELIST:" . join(":::",@metalist));
- # 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.
- }
- # reply with result
+ #
+ &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
+ } 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
+ #
+ # close the database handle
$dbh->disconnect
- or &logthis("<font color=blue>WARNING: Couldn't disconnect from database $DBI::errstr ($st secs): $@</font>");
-
+ 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.
@@ -267,14 +428,179 @@ sub make_new_child {
}
}
-sub DISCONNECT {
- $dbh->disconnect or
- &logthis("<font color=blue>WARNING: Couldn't disconnect from database $DBI::errstr ($st secs): $@</font>");
- exit;
+########################################################
+########################################################
+
+=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'};
+ my $fh=IO::File->new(">>$execdir/logs/lonsql.log");
+ my $now=time;
+ my $local=localtime($now);
+ print $fh "$local ($$): $message\n";
}
# -------------------------------------------------- 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";
@@ -285,10 +611,27 @@ 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;
@@ -300,22 +643,300 @@ sub reply {
}
} else {
$answer='self_reply';
+ $answer=subreply($cmd,$server);
}
return $answer;
}
-# -------------------------------------------------------- Escape Special Chars
+########################################################
+########################################################
+
+=pod
+
+=item &escape
+Escape special characters in a string.
+
+Inputs: string to escape
+
+Returns: The input string with special characters escaped.
+
+=cut
+
+########################################################
+########################################################
sub escape {
my $str=shift;
$str =~ s/(\W)/"%".unpack('H2',$1)/eg;
return $str;
}
-# ----------------------------------------------------- Un-Escape Special Chars
+########################################################
+########################################################
+
+=pod
+
+=item &unescape
+
+Unescape special characters in a string.
+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;
}
+
+########################################################
+########################################################
+
+=pod
+
+=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.
+
+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 $proname) {
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+########################################################
+########################################################
+
+=pod
+
+=item &propath
+
+Inputs: user name, user domain
+
+Returns: The full path to the users directory.
+
+=cut
+
+########################################################
+########################################################
+sub propath {
+ my ($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);
+ }
+ }
+ 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