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Diff for /loncom/interface/loncoursedata.pm between versions 1.2 and 1.69

version 1.2, 2002/07/17 12:38:25 version 1.69, 2003/04/18 19:05:30
Line 1 Line 1
 # The LearningOnline Network with CAPA  # The LearningOnline Network with CAPA
 # (Publication Handler  
 #  #
 # $Id$  # $Id$
 #  #
Line 35  loncoursedata Line 34  loncoursedata
   
 =head1 SYNOPSIS  =head1 SYNOPSIS
   
 Set of functions that download and process student information.  Set of functions that download and process student and course information.
   
 =head1 PACKAGES USED  =head1 PACKAGES USED
   
  Apache::Constants qw(:common :http)   Apache::Constants qw(:common :http)
  Apache::lonnet()   Apache::lonnet()
    Apache::lonhtmlcommon
  HTML::TokeParser   HTML::TokeParser
  GDBM_File   GDBM_File
   
Line 51  package Apache::loncoursedata; Line 51  package Apache::loncoursedata;
 use strict;  use strict;
 use Apache::Constants qw(:common :http);  use Apache::Constants qw(:common :http);
 use Apache::lonnet();  use Apache::lonnet();
   use Apache::lonhtmlcommon;
   use Time::HiRes;
   use Apache::lonmysql;
 use HTML::TokeParser;  use HTML::TokeParser;
 use GDBM_File;  use GDBM_File;
   
Line 58  use GDBM_File; Line 61  use GDBM_File;
   
 =head1 DOWNLOAD INFORMATION  =head1 DOWNLOAD INFORMATION
   
 This section contains all the files that get data from other servers   This section contains all the functions that get data from other servers 
 and/or itself.  There is one function that has a call to get remote  and/or itself.
 information but isn't included here which is ProcessTopLevelMap.  The  
 usage was small enough to be ignored, but that portion may be moved  
 here in the future.  
   
 =cut  =cut
   
 # ----- DOWNLOAD INFORMATION -------------------------------------------  ####################################################
   ####################################################
   
 =pod  =pod
   
 =item &DownloadNamePIDSection()  =item &get_sequence_assessment_data()
   
 Collects lastname, generation, middlename, firstname, PID, and section for each  AT THIS TIME THE USE OF THIS FUNCTION IS *NOT* RECOMMENDED
 student from their environment database.  The list of students is built from  
 collecting a classlist for the course that is to be displayed.  
   
 =over 4  Use lonnavmaps to build a data structure describing the order and 
   assessment contents of each sequence in the current course.
   
 Input: $courseID, $c  The returned structure is a hash reference. 
   
 $courseID:  The id of the course  { title => 'title',
     symb  => 'symb',
     src   => '/s/o/u/r/c/e',
     type  => (container|assessment),
     num_assess   => 2,               # only for container
     parts        => [11,13,15],      # only for assessment
     response_ids => [12,14,16],      # only for assessment
     contents     => [........]       # only for container
   }
   
 $c: The connection class that can determine if the browser has aborted.  It  $hash->{'contents'} is a reference to an array of hashes of the same structure.
 is used to short circuit this function so that it doesn't continue to   
 get information when there is no need.  
   
 Output: \%classlist  Also returned are array references to the sequences and assessments contained
   in the course.
   
 \%classlist: A pointer to a hash containing the following data:  
   
 -A list of student name:domain (as keys) (known below as $name)  =cut
   
 -A hash pointer for each student containing lastname, generation, firstname,  ####################################################
 middlename, and PID : Key is $name.'studentInformation'  ####################################################
   sub get_sequence_assessment_data {
       my $fn=$ENV{'request.course.fn'};
       ##
       ## use navmaps
       my $navmap = Apache::lonnavmaps::navmap->new($fn.".db",
                                                    $fn."_parms.db",1,0);
       if (!defined($navmap)) {
           return 'Can not open Coursemap';
       }
       my $iterator = $navmap->getIterator(undef, undef, undef, 1);
       my $curRes = $iterator->next(); # Top level sequence
       ##
       ## Prime the pump 
       ## 
       ## We are going to loop until we run out of sequences/pages to explore for
       ## resources.  This means we have to start out with something to look
       ## at.
       my $title = $ENV{'course.'.$ENV{'request.course.id'}.'.description'};
       my $symb  = 'top';
       my $src   = 'not applicable';
       #
       my @Sequences; 
       my @Assessments;
       my @Nested_Sequences = ();   # Stack of sequences, keeps track of depth
       my $top = { title    => $title,
                   src      => $src,
                   symb     => $symb,
                   type     => 'container',
                   num_assess => 0,
                   num_assess_parts => 0,
                   contents   => [], };
       push (@Sequences,$top);
       push (@Nested_Sequences, $top);
       #
       # We need to keep track of which sequences contain homework problems
       # 
       my $previous;
       while (scalar(@Nested_Sequences)) {
           $previous = $curRes;
           $curRes = $iterator->next();
           my $currentmap = $Nested_Sequences[-1]; # Last one on the stack
           if ($curRes == $iterator->BEGIN_MAP()) {
               # get the map itself, instead of BEGIN_MAP
               $title = $previous->title();
               $symb  = $previous->symb();
               $src   = $previous->src();
               my $newmap = { title    => $title,
                              src      => $src,
                              symb     => $symb,
                              type     => 'container',
                              num_assess => 0,
                              contents   => [],
                          };
               push (@{$currentmap->{'contents'}},$newmap); # this is permanent
               push (@Sequences,$newmap);
               push (@Nested_Sequences, $newmap); # this is a stack
               next;
           }
           if ($curRes == $iterator->END_MAP()) {
               pop(@Nested_Sequences);
               next;
           }
           next if (! ref($curRes));
           next if (! $curRes->is_problem());# && !$curRes->randomout);
           # Okay, from here on out we only deal with assessments
           $title = $curRes->title();
           $symb  = $curRes->symb();
           $src   = $curRes->src();
           my $parts = $curRes->parts();
           my $assessment = { title => $title,
                              src   => $src,
                              symb  => $symb,
                              type  => 'assessment',
                              parts => $parts,
                              num_parts => scalar(@$parts),
                          };
           push(@Assessments,$assessment);
           push(@{$currentmap->{'contents'}},$assessment);
           $currentmap->{'num_assess'}++;
           $currentmap->{'num_assess_parts'}+= scalar(@$parts);
       }
       $navmap->untieHashes();
       return ($top,\@Sequences,\@Assessments);
   }
   
 -A hash pointer to each students section data : Key is $name.section  sub LoadDiscussion {
       my ($courseID)=@_;
       my %Discuss=();
       my %contrib=&Apache::lonnet::dump(
                   $courseID,
                   $ENV{'course.'.$courseID.'.domain'},
                   $ENV{'course.'.$courseID.'.num'});
     
       #my %contrib=&DownloadCourseInformation($name, $courseID, 0);
   
       foreach my $temp(keys %contrib) {
    if ($temp=~/^version/) {
       my $ver=$contrib{$temp};
       my ($dummy,$prb)=split(':',$temp);
       for (my $idx=1; $idx<=$ver; $idx++ ) {
    my $name=$contrib{"$idx:$prb:sendername"};
    $Discuss{"$name:$prb"}=$idx;
       }
    }
       }       
   
 =back      return \%Discuss;
   }
   
   =pod
   
   =item &ProcessFullName()
   
   Takes lastname, generation, firstname, and middlename (or some partial
   set of this data) and returns the full name version as a string.  Format
   is Lastname generation, firstname middlename or a subset of this.
   
 =cut  =cut
   
 sub DownloadStudentNamePIDSection {  sub ProcessFullName {
     my ($courseID, $c)=@_;      my ($lastname, $generation, $firstname, $middlename)=@_;
     my ($courseDomain,$courseNumber)=split(/\_/,$courseID);      my $Str = '';
   
     my %classlist=&Apache::lonnet::dump('classlist',$courseDomain,      # Strip whitespace preceeding & following name components.
                                         $courseNumber);      $lastname   =~ s/(\s+$|^\s+)//g;
     my ($checkForError)=keys (%classlist);      $generation =~ s/(\s+$|^\s+)//g;
     if($checkForError =~ /^(con_lost|error|no_such_host)/i) {      $firstname  =~ s/(\s+$|^\s+)//g;
         return \%classlist;      $middlename =~ s/(\s+$|^\s+)//g;
   
       if($lastname ne '') {
    $Str .= $lastname;
    $Str .= ' '.$generation if ($generation ne '');
    $Str .= ',';
           $Str .= ' '.$firstname  if ($firstname ne '');
           $Str .= ' '.$middlename if ($middlename ne '');
       } else {
           $Str .= $firstname      if ($firstname ne '');
           $Str .= ' '.$middlename if ($middlename ne '');
           $Str .= ' '.$generation if ($generation ne '');
     }      }
   
     foreach my $name (keys(%classlist)) {      return $Str;
         if($c->aborted()) {  }
             $classlist{'error'}='aborted';  
             return \%classlist;  
         }  
   
         my ($studentName,$studentDomain) = split(/\:/,$name);  ################################################
         # Download student environment data, specifically the full name and id.  ################################################
         my %studentInformation=&Apache::lonnet::get('environment',  
                                                     ['lastname','generation',  
                                                      'firstname','middlename',  
                                                      'id'],  
                                                     $studentDomain,  
                                                     $studentName);  
         $classlist{$name.':studentInformation'}=\%studentInformation;  
   
         if($c->aborted()) {  =pod
             $classlist{'error'}='aborted';  
             return \%classlist;  
         }  
   
         #Section  =item &make_into_hash($values);
         my %section=&Apache::lonnet::dump('roles',$studentDomain,$studentName);  
         $classlist{$name.':section'}=\%section;  Returns a reference to a hash as described by $values.  $values is
     }  assumed to be the result of 
       join(':',map {&Apache::lonnet::escape($_)} %orighash);
   
   This is a helper function for get_current_state.
   
     return \%classlist;  =cut
   
   ################################################
   ################################################
   sub make_into_hash {
       my $values = shift;
       my %tmp = map { &Apache::lonnet::unescape($_); }
                                              split(':',$values);
       return \%tmp;
 }  }
   
   
   ################################################
   ################################################
   
 =pod  =pod
   
 =item &DownloadStudentCourseInformation()  =head1 LOCAL DATA CACHING SUBROUTINES
   
   The local caching is done using MySQL.  There is no fall-back implementation
   if MySQL is not running.
   
   The programmers interface is to call &get_current_state() or some other
   primary interface subroutine (described below).  The internals of this 
   storage system are documented here.
   
   There are six tables used to store student performance data (the results of
   a dumpcurrent).  Each of these tables is created in MySQL with a name of
   $courseid_*****, where ***** is 'symb', 'part', or whatever is appropriate 
   for the table.  The tables and their purposes are described below.
   
   Some notes before we get started.
   
 Dump of all the course information for a single student.  There is no  Each table must have a PRIMARY KEY, which is a column or set of columns which
 pruning of data, it is all stored in a hash and returned.  will serve to uniquely identify a row of data.  NULL is not allowed!
   
   INDEXes work best on integer data.
   
   JOIN is used to combine data from many tables into one output.
   
   lonmysql.pm is used for some of the interface, specifically the table creation
   calls.  The inserts are done in bulk by directly calling the database handler.
   The SELECT ... JOIN statement used to retrieve the data does not have an
   interface in lonmysql.pm and I shudder at the thought of writing one.
   
   =head3 Table Descriptions
   
 =over 4  =over 4
   
 Input: $name, $courseID  =item $symb_table
   
 $name: student name:domain  The symb_table has two columns.  The first is a 'symb_id' and the second
   is the text name for the 'symb' (limited to 64k).  The 'symb_id' is generated
   automatically by MySQL so inserts should be done on this table with an
   empty first element.  This table has its PRIMARY KEY on the 'symb_id'.
   
   =item $part_table
   
   The part_table has two columns.  The first is a 'part_id' and the second
   is the text name for the 'part' (limited to 100 characters).  The 'part_id' is
   generated automatically by MySQL so inserts should be done on this table with
   an empty first element.  This table has its PRIMARY KEY on the 'part' (100
   characters) and a KEY on 'part_id'.
   
   =item $student_table
   
   The student_table has two columns.  The first is a 'student_id' and the second
   is the text description of the 'student' (typically username:domain) (less
   than 100 characters).  The 'student_id' is automatically generated by MySQL.
   The use of the name 'student_id' is loaded, I know, but this ID is used ONLY 
   internally to the MySQL database and is not the same as the students ID 
   (stored in the students environment).  This table has its PRIMARY KEY on the
   'student' (100 characters).
   
   =item $updatetime_table
   
   The updatetime_table has two columns.  The first is 'student' (100 characters,
   typically username:domain).  The second is 'updatetime', which is an unsigned
   integer, NOT a MySQL date.  This table has its PRIMARY KEY on 'student' (100
   characters).
   
   =item $performance_table
   
   The performance_table has 9 columns.  The first three are 'symb_id', 
   'student_id', and 'part_id'.  These comprise the PRIMARY KEY for this table
   and are directly related to the $symb_table, $student_table, and $part_table
   described above.  MySQL does better indexing on numeric items than text,
   so we use these three "index tables".  The remaining columns are
   'solved', 'tries', 'awarded', 'award', 'awarddetail', and 'timestamp'.
   These are either the MySQL type TINYTEXT or various integers ('tries' and 
   'timestamp').  This table has KEYs of 'student_id' and 'symb_id'.
   For use of this table, see the functions described below.
   
   =item $parameters_table
   
   The parameters_table holds the data that does not fit neatly into the
   performance_table.  The parameters table has four columns: 'symb_id',
   'student_id', 'parameter', and 'value'.  'symb_id', 'student_id', and
   'parameter' comprise the PRIMARY KEY for this table.  'parameter' is 
   limited to 255 characters.  'value' is limited to 64k characters.
   
 $courseID:  The id of the course  =back
   
   =head3 Important Subroutines
   
 Output: \%courseData  Here is a brief overview of the subroutines which are likely to be of 
   interest:
   
   =over 4
   
 \%courseData:  A hash pointer to the raw data from the student's course  =item &get_current_state(): programmers interface.
 database.  
   =item &init_dbs(): table creation
   
   =item &update_student_data(): data storage calls
   
   =item &get_student_data_from_performance_cache(): data retrieval
   
 =back  =back
   
   =head3 Main Documentation
   
   =over 4
   
 =cut  =cut
   
 sub DownloadStudentCourseInformation {  ################################################
     my ($name,$courseID)=@_;  ################################################
     my ($studentName,$studentDomain) = split(/\:/,$name);  
   
     # Download student course data  ################################################
     my %courseData=&Apache::lonnet::dump($courseID,$studentDomain,  ################################################
  $studentName);  {
     return \%courseData;  
 }  my $current_course ='';
   my $symb_table;
   my $part_table;
   my $student_table;
   my $updatetime_table;
   my $performance_table;
   my $parameters_table;
   
 # ----- END DOWNLOAD INFORMATION ---------------------------------------  ################################################
   ################################################
   
 =pod  =pod
   
 =head1 PROCESSING FUNCTIONS  =item &init_dbs()
   
 These functions process all the data for all the students.  Also, they  Input: course id
 are the only functions that access the cache database for writing.  Thus  
 they are the only functions that cache data.  The downloading and caching  Output: 0 on success, positive integer on error
 were separated to reduce problems with stopping downloading then can't  
 tie hash to database later.  This routine issues the calls to lonmysql to create the tables used to
   store student data.
   
 =cut  =cut
   
 # ----- PROCESSING FUNCTIONS ---------------------------------------  ################################################
   ################################################
   sub init_dbs {
       my $courseid = shift;
       &setup_table_names($courseid);
       #
       # Note - changes to this table must be reflected in the code that 
       # stores the data (calls &Apache::lonmysql::store_row with this table
       # id
       my $symb_table_def = {
           id => $symb_table,
           permanent => 'no',
           columns => [{ name => 'symb_id',
                         type => 'MEDIUMINT UNSIGNED',
                         restrictions => 'NOT NULL',
                         auto_inc     => 'yes', },
                       { name => 'symb',
                         type => 'MEDIUMTEXT',
                         restrictions => 'NOT NULL'},
                       ],
           'PRIMARY KEY' => ['symb_id'],
       };
       #
       my $part_table_def = {
           id => $part_table,
           permanent => 'no',
           columns => [{ name => 'part_id',
                         type => 'MEDIUMINT UNSIGNED',
                         restrictions => 'NOT NULL',
                         auto_inc     => 'yes', },
                       { name => 'part',
                         type => 'VARCHAR(100)',
                         restrictions => 'NOT NULL'},
                       ],
           'PRIMARY KEY' => ['part (100)'],
           'KEY' => [{ columns => ['part_id']},],
       };
       #
       my $student_table_def = {
           id => $student_table,
           permanent => 'no',
           columns => [{ name => 'student_id',
                         type => 'MEDIUMINT UNSIGNED',
                         restrictions => 'NOT NULL',
                         auto_inc     => 'yes', },
                       { name => 'student',
                         type => 'VARCHAR(100)',
                         restrictions => 'NOT NULL'},
                       ],
           'PRIMARY KEY' => ['student (100)'],
           'KEY' => [{ columns => ['student_id']},],
       };
       #
       my $updatetime_table_def = {
           id => $updatetime_table,
           permanent => 'no',
           columns => [{ name => 'student',
                         type => 'VARCHAR(100)',
                         restrictions => 'NOT NULL UNIQUE',},
                       { name => 'updatetime',
                         type => 'INT UNSIGNED',
                         restrictions => 'NOT NULL' },
                       ],
           'PRIMARY KEY' => ['student (100)'],
       };
       #
       my $performance_table_def = {
           id => $performance_table,
           permanent => 'no',
           columns => [{ name => 'symb_id',
                         type => 'MEDIUMINT UNSIGNED',
                         restrictions => 'NOT NULL'  },
                       { name => 'student_id',
                         type => 'MEDIUMINT UNSIGNED',
                         restrictions => 'NOT NULL'  },
                       { name => 'part_id',
                         type => 'MEDIUMINT UNSIGNED',
                         restrictions => 'NOT NULL' },
                       { name => 'solved',
                         type => 'TINYTEXT' },
                       { name => 'tries',
                         type => 'SMALLINT UNSIGNED' },
                       { name => 'awarded',
                         type => 'TINYTEXT' },
                       { name => 'award',
                         type => 'TINYTEXT' },
                       { name => 'awarddetail',
                         type => 'TINYTEXT' },
                       { name => 'timestamp',
                         type => 'INT UNSIGNED'},
                       ],
           'PRIMARY KEY' => ['symb_id','student_id','part_id'],
           'KEY' => [{ columns=>['student_id'] },
                     { columns=>['symb_id'] },],
       };
       #
       my $parameters_table_def = {
           id => $parameters_table,
           permanent => 'no',
           columns => [{ name => 'symb_id',
                         type => 'MEDIUMINT UNSIGNED',
                         restrictions => 'NOT NULL'  },
                       { name => 'student_id',
                         type => 'MEDIUMINT UNSIGNED',
                         restrictions => 'NOT NULL'  },
                       { name => 'parameter',
                         type => 'TINYTEXT',
                         restrictions => 'NOT NULL'  },
                       { name => 'value',
                         type => 'MEDIUMTEXT' },
                       ],
           'PRIMARY KEY' => ['symb_id','student_id','parameter (255)'],
       };
       #
       # Create the tables
       my $tableid;
       $tableid = &Apache::lonmysql::create_table($symb_table_def);
       if (! defined($tableid)) {
           &Apache::lonnet::logthis("error creating symb_table: ".
                                    &Apache::lonmysql::get_error());
           return 1;
       }
       #
       $tableid = &Apache::lonmysql::create_table($part_table_def);
       if (! defined($tableid)) {
           &Apache::lonnet::logthis("error creating part_table: ".
                                    &Apache::lonmysql::get_error());
           return 2;
       }
       #
       $tableid = &Apache::lonmysql::create_table($student_table_def);
       if (! defined($tableid)) {
           &Apache::lonnet::logthis("error creating student_table: ".
                                    &Apache::lonmysql::get_error());
           return 3;
       }
       #
       $tableid = &Apache::lonmysql::create_table($updatetime_table_def);
       if (! defined($tableid)) {
           &Apache::lonnet::logthis("error creating updatetime_table: ".
                                    &Apache::lonmysql::get_error());
           return 4;
       }
       #
       $tableid = &Apache::lonmysql::create_table($performance_table_def);
       if (! defined($tableid)) {
           &Apache::lonnet::logthis("error creating preformance_table: ".
                                    &Apache::lonmysql::get_error());
           return 5;
       }
       #
       $tableid = &Apache::lonmysql::create_table($parameters_table_def);
       if (! defined($tableid)) {
           &Apache::lonnet::logthis("error creating parameters_table: ".
                                    &Apache::lonmysql::get_error());
           return 6;
       }
       return 0;
   }
   
   ################################################
   ################################################
   
 =pod  =pod
   
 =item &ProcessTopResourceMap()  =item &get_part_id()
   
 Trace through the "big hash" created in rat/lonuserstate.pm::loadmap.    Get the MySQL id of a problem part string.
 Basically, this function organizes a subset of the data and stores it in  
 cached data.  The data stored is the problems, sequences, sequence titles,  
 parts of problems, and their ordering.  Column width information is also   
 partially handled here on a per sequence basis.  
   
 =over 4  Input: $part
   
 Input: $cache, $c  Output: undef on error, integer $part_id on success.
   
 $cache:  A pointer to a hash to store the information  =item &get_part()
   
 $c:  The connection class used to determine if an abort has been sent to the   Get the string describing a part from the MySQL id of the problem part.
 browser  
   
 Output: A string that contains an error message or "OK" if everything went   Input: $part_id
 smoothly.  
   
 =back  Output: undef on error, $part string on success.
   
 =cut  =cut
   
 sub ProcessTopResourceMap {  ################################################
     my ($cache,$c)=@_;  ################################################
     my %hash;  
     my $fn=$ENV{'request.course.fn'};  my $have_read_part_table = 0;
     if(-e "$fn.db") {  my %ids_by_part;
  my $tieTries=0;  my %parts_by_id;
  while($tieTries < 3) {  
             if($c->aborted()) {  sub get_part_id {
                 return;      my ($part) = @_;
             }      $part = 0 if (! defined($part));
     if(tie(%hash,'GDBM_File',"$fn.db",&GDBM_READER,0640)) {      if (! $have_read_part_table) {
  last;          my @Result = &Apache::lonmysql::get_rows($part_table);
     }          foreach (@Result) {
     $tieTries++;              $ids_by_part{$_->[1]}=$_->[0];
     sleep 1;          }
  }          $have_read_part_table = 1;
  if($tieTries >= 3) {      }
             return 'Coursemap undefined.';      if (! exists($ids_by_part{$part})) {
           &Apache::lonmysql::store_row($part_table,[undef,$part]);
           undef(%ids_by_part);
           my @Result = &Apache::lonmysql::get_rows($part_table);
           foreach (@Result) {
               $ids_by_part{$_->[1]}=$_->[0];
         }          }
     } else {  
         return 'Can not open Coursemap.';  
     }      }
       return $ids_by_part{$part} if (exists($ids_by_part{$part}));
       return undef; # error
   }
   
     # Initialize state machine.  Set information pointing to top level map.  sub get_part {
     my (@sequences, @currentResource, @finishResource);      my ($part_id) = @_;
     my ($currentSequence, $currentResourceID, $lastResourceID);      if (! exists($parts_by_id{$part_id})  || 
           ! defined($parts_by_id{$part_id}) ||
     $currentResourceID=$hash{'ids_/res/'.$ENV{'request.course.uri'}};          $parts_by_id{$part_id} eq '') {
     push(@currentResource, $currentResourceID);          my @Result = &Apache::lonmysql::get_rows($part_table);
     $lastResourceID=-1;          foreach (@Result) {
     $currentSequence=-1;              $parts_by_id{$_->[0]}=$_->[1];
     my $topLevelSequenceNumber = $currentSequence;          }
       }
     while(1) {      return $parts_by_id{$part_id} if(exists($parts_by_id{$part_id}));
         if($c->aborted()) {      return undef; # error
             last;  }
         }  
  # HANDLE NEW SEQUENCE!  
  #if page || sequence  
  if(defined($hash{'map_pc_'.$hash{'src_'.$currentResourceID}})) {  
     push(@sequences, $currentSequence);  
     push(@currentResource, $currentResourceID);  
     push(@finishResource, $lastResourceID);  
   
     $currentSequence=$hash{'map_pc_'.$hash{'src_'.$currentResourceID}};  
   
             # Mark sequence as containing problems.  If it doesn't, then  
             # it will be removed when processing for this sequence is  
             # complete.  This allows the problems in a sequence  
             # to be outputed before problems in the subsequences  
             if(!defined($cache->{'orderedSequences'})) {  
                 $cache->{'orderedSequences'}=$currentSequence;  
             } else {  
                 $cache->{'orderedSequences'}.=':'.$currentSequence;  
             }  
   
     $lastResourceID=$hash{'map_finish_'.  ################################################
   $hash{'src_'.$currentResourceID}};  ################################################
     $currentResourceID=$hash{'map_start_'.  
      $hash{'src_'.$currentResourceID}};  
   
     if(!($currentResourceID) || !($lastResourceID)) {  
  $currentSequence=pop(@sequences);  
  $currentResourceID=pop(@currentResource);  
  $lastResourceID=pop(@finishResource);  
  if($currentSequence eq $topLevelSequenceNumber) {  
     last;  
  }  
     }  
  }  
   
  # Handle gradable resources: exams, problems, etc  =pod
  $currentResourceID=~/(\d+)\.(\d+)/;  
         my $partA=$1;  
         my $partB=$2;  
  if($hash{'src_'.$currentResourceID}=~  
    /\.(problem|exam|quiz|assess|survey|form)$/ &&  
    $partA eq $currentSequence) {  
     my $Problem = &Apache::lonnet::symbclean(  
   &Apache::lonnet::declutter($hash{'map_id_'.$partA}).  
   '___'.$partB.'___'.  
   &Apache::lonnet::declutter($hash{'src_'.  
  $currentResourceID}));  
   
     $cache->{$currentResourceID.':problem'}=$Problem;  
     if(!defined($cache->{$currentSequence.':problems'})) {  
  $cache->{$currentSequence.':problems'}=$currentResourceID;  
     } else {  
  $cache->{$currentSequence.':problems'}.=  
     ':'.$currentResourceID;  
     }  
   
     my $meta=$hash{'src_'.$currentResourceID};  =item &get_symb_id()
 #            $cache->{$currentResourceID.':title'}=  
 #                &Apache::lonnet::metdata($meta,'title');  
             $cache->{$currentResourceID.':title'}=  
                 $hash{'title_'.$currentResourceID};  
   
             # Get Parts for problem  
     foreach (split(/\,/,&Apache::lonnet::metadata($meta,'keys'))) {  
  if($_=~/^stores\_(\d+)\_tries$/) {  
     my $Part=&Apache::lonnet::metadata($meta,$_.'.part');  
                     if(!defined($cache->{$currentSequence.':'.  
                                           $currentResourceID.':parts'})) {  
                         $cache->{$currentSequence.':'.$currentResourceID.  
                                    ':parts'}=$Part;  
                     } else {  
                         $cache->{$currentSequence.':'.$currentResourceID.  
                                    ':parts'}.=':'.$Part;  
                     }  
                     foreach (split(/\,/,  
                              &Apache::lonnet::metadata($meta,'packages'))) {  
                         if($_=~/^optionresponse\_($Part)\_(\w+)$/) {  
                             if(defined($cache->{'OptionResponses'})) {  
                                 $cache->{'OptionResponses'}.= ':::'.  
                                     $hash{'src_'.$currentResourceID}.'::'.  
                                     $hash{'title_'.$currentResourceID}.'::'.  
                                     $Part.'::'.$Problem;  
                             } else {  
                                 $cache->{'OptionResponses'}=  
                                     $hash{'src_'.$currentResourceID}.'::'.  
                                     $hash{'title_'.$currentResourceID}.'::'.  
                                     $Part.'::'.$Problem;  
                             }  
                         }  
                     }  
                 }  
     }  
  }  
   
  # if resource == finish resource, then it is the end of a sequence/page  Get the MySQL id of a symb.
  if($currentResourceID eq $lastResourceID) {  
     # pop off last resource of sequence  
     $currentResourceID=pop(@currentResource);  
     $lastResourceID=pop(@finishResource);  
   
     if(defined($cache->{$currentSequence.':problems'})) {  
  # Capture sequence information here  
  $cache->{$currentSequence.':title'}=  
     $hash{'title_'.$currentResourceID};  
                 $cache->{$currentSequence.':source'}=  
                     $hash{'src_'.$currentResourceID};  
   
                 my $totalProblems=0;  
                 foreach my $currentProblem (split(/\:/,  
                                                $cache->{$currentSequence.  
                                                ':problems'})) {  
                     foreach (split(/\:/,$cache->{$currentSequence.':'.  
                                                    $currentProblem.  
                                                    ':parts'})) {  
                         $totalProblems++;  
                     }  
                 }  
  my @titleLength=split(//,$cache->{$currentSequence.  
                                                     ':title'});  
                 # $extra is 3 for problems correct and 3 for space  
                 # between problems correct and problem output  
                 my $extra = 6;  
  if(($totalProblems + $extra) > (scalar @titleLength)) {  
     $cache->{$currentSequence.':columnWidth'}=  
                         $totalProblems + $extra;  
  } else {  
     $cache->{$currentSequence.':columnWidth'}=  
                         (scalar @titleLength);  
  }  
     } else {  
                 # Remove sequence from list, if it contains no problems to  
                 # display.  
                 $cache->{'orderedSequences'}=~s/$currentSequence//;  
                 $cache->{'orderedSequences'}=~s/::/:/g;  
                 $cache->{'orderedSequences'}=~s/^:|:$//g;  
             }  
   
     $currentSequence=pop(@sequences);  Input: $symb
     if($currentSequence eq $topLevelSequenceNumber) {  
  last;  
     }  
  }  
   
  # MOVE!!!  Output: undef on error, integer $symb_id on success.
  # move to next resource  
  unless(defined($hash{'to_'.$currentResourceID})) {  
     # big problem, need to handle.  Next is probably wrong  
     last;  
  }  
  my @nextResources=();  
  foreach (split(/\,/,$hash{'to_'.$currentResourceID})) {  
     push(@nextResources, $hash{'goesto_'.$_});  
  }  
  push(@currentResource, @nextResources);  
  # Set the next resource to be processed  
  $currentResourceID=pop(@currentResource);  
     }  
   
     unless (untie(%hash)) {  =item &get_symb()
         &Apache::lonnet::logthis("<font color=blue>WARNING: ".  
                                  "Could not untie coursemap $fn (browse)".  
                                  ".</font>");   
     }  
   
     return 'OK';  Get the symb associated with a MySQL symb_id.
 }  
   
 =pod  Input: $symb_id
   
 =item &ProcessSection()  Output: undef on error, $symb on success.
   
 Determine the section number for a student for the class.  A student can have   =cut
 multiple sections for the same class.  The correct one is chosen.  
   
 =over 4  ################################################
   ################################################
   
   my $have_read_symb_table = 0;
   my %ids_by_symb;
   my %symbs_by_id;
   
   sub get_symb_id {
       my ($symb) = @_;
       if (! $have_read_symb_table) {
           my @Result = &Apache::lonmysql::get_rows($symb_table);
           foreach (@Result) {
               $ids_by_symb{$_->[1]}=$_->[0];
           }
           $have_read_symb_table = 1;
       }
       if (! exists($ids_by_symb{$symb})) {
           &Apache::lonmysql::store_row($symb_table,[undef,$symb]);
           undef(%ids_by_symb);
           my @Result = &Apache::lonmysql::get_rows($symb_table);
           foreach (@Result) {
               $ids_by_symb{$_->[1]}=$_->[0];
           }
       }
       return $ids_by_symb{$symb} if(exists( $ids_by_symb{$symb}));
       return undef; # error
   }
   
 Input: $sectionData, $courseid, $ActiveFlag  sub get_symb {
       my ($symb_id) = @_;
       if (! exists($symbs_by_id{$symb_id})  || 
           ! defined($symbs_by_id{$symb_id}) ||
           $symbs_by_id{$symb_id} eq '') {
           my @Result = &Apache::lonmysql::get_rows($symb_table);
           foreach (@Result) {
               $symbs_by_id{$_->[0]}=$_->[1];
           }
       }
       return $symbs_by_id{$symb_id} if(exists( $symbs_by_id{$symb_id}));
       return undef; # error
   }
   
 $sectionData:  A pointer to a hash containing all section data for this   ################################################
 student for the class  ################################################
   
 $courseid:  The course ID.  =pod
   
 $ActiveFlag:  The student's active status (Active/Expired)  =item &get_student_id()
   
 Output: $oldsection, $cursection, or -1  Get the MySQL id of a student.
   
 $oldsection and $cursection and sections number that will be displayed in the   Input: $sname, $dom
 chart.  
   
 -1 is returned if an error occurs.  Output: undef on error, integer $student_id on success.
   
 =back  =item &get_student()
   
   Get student username:domain associated with the MySQL student_id.
   
   Input: $student_id
   
   Output: undef on error, string $student (username:domain) on success.
   
 =cut  =cut
   
 sub ProcessSection {  ################################################
     my ($sectionData,$courseid,$ActiveFlag)=@_;  ################################################
     $courseid=~s/\_/\//g;  
     $courseid=~s/^(\w)/\/$1/;  
   
     my $cursection='-1';  
     my $oldsection='-1';  
     my $status='Expired';  
     my $section='';  
     foreach my $key (keys (%$sectionData)) {  
  my $value = $sectionData->{$key};  
         if ($key=~/^$courseid(?:\/)*(\w+)*\_st$/) {  
     $section=$1;  
     if($key eq $courseid.'_st') {  
  $section='';  
     }  
   
     my ($dummy,$end,$start)=split(/\_/,$value);  my $have_read_student_table = 0;
     my $now=time;  my %ids_by_student;
             my $notactive=0;  my %students_by_id;
             if ($start) {  
                 if($now<$start) {  sub get_student_id {
                     $notactive=1;      my ($sname,$sdom) = @_;
                 }      my $student = $sname.':'.$sdom;
             }      if (! $have_read_student_table) {
             if($end) {          my @Result = &Apache::lonmysql::get_rows($student_table);
                 if ($now>$end) {          foreach (@Result) {
                     $notactive=1;              $ids_by_student{$_->[1]}=$_->[0];
                 }          }
             }          $have_read_student_table = 1;
             if($notactive == 0) {  
                 $status='Active';  
                 $cursection=$section;  
                 last;  
             }  
             if($notactive == 1) {  
                 $oldsection=$section;  
             }  
  }  
     }      }
     if($status eq $ActiveFlag) {      if (! exists($ids_by_student{$student})) {
         if($cursection eq '-1') {          &Apache::lonmysql::store_row($student_table,[undef,$student]);
             return $oldsection;          undef(%ids_by_student);
           my @Result = &Apache::lonmysql::get_rows($student_table);
           foreach (@Result) {
               $ids_by_student{$_->[1]}=$_->[0];
         }          }
         return $cursection;  
     }      }
     if($ActiveFlag eq 'Any') {      return $ids_by_student{$student} if(exists( $ids_by_student{$student}));
         if($cursection eq '-1') {      return undef; # error
             return $oldsection;  }
   
   sub get_student {
       my ($student_id) = @_;
       if (! exists($students_by_id{$student_id})  || 
           ! defined($students_by_id{$student_id}) ||
           $students_by_id{$student_id} eq '') {
           my @Result = &Apache::lonmysql::get_rows($student_table);
           foreach (@Result) {
               $students_by_id{$_->[0]}=$_->[1];
         }          }
         return $cursection;  
     }      }
     return '-1';      return $students_by_id{$student_id} if(exists($students_by_id{$student_id}));
       return undef; # error
 }  }
   
 =pod  ################################################
   ################################################
   
 =item &ProcessNamePIDSection()  =pod
   
 Takes data downloaded for a student and breaks it up into managable pieces and   =item &update_student_data()
 stored in cache data.  The username, domain, class related date, PID,   
 full name, and section are all processed here.  
   
 =over 4  Input: $sname, $sdom, $courseid
   
 Input: $cache, $studentInformation, $section, $date, $name, $courseID  Output: $returnstatus, \%student_data
   
 $cache:  A hash pointer to store the data  $returnstatus is a string describing any errors that occured.  'okay' is the
   default.
   \%student_data is the data returned by a call to lonnet::currentdump.
   
   This subroutine loads a students data using lonnet::currentdump and inserts
   it into the MySQL database.  The inserts are done on two tables, 
   $performance_table and $parameters_table.  $parameters_table holds the data 
   that is not included in $performance_table.  See the description of 
   $performance_table elsewhere in this file.  The INSERT calls are made
   directly by this subroutine, not through lonmysql because we do a 'bulk'
   insert which takes advantage of MySQLs non-SQL compliant INSERT command to 
   insert multiple rows at a time.  If anything has gone wrong during this
   process, $returnstatus is updated with a description of the error and
   \%student_data is returned.  
   
   Notice we do not insert the data and immediately query it.  This means it
   is possible for there to be data returned this first time that is not 
   available the second time.  CYA.
   
 $studentInformation:  Student information is what was requested in   =cut
 &DownloadPrerequistedData().  See that function for what data is requested.  
   
 $section: A hash pointer to class section related information.  ################################################
   ################################################
   sub update_student_data {
       my ($sname,$sdom,$courseid) = @_;
       #
       # Set up database names
       &setup_table_names($courseid);
       #
       my $student_id = &get_student_id($sname,$sdom);
       my $student = $sname.':'.$sdom;
       #
       my $returnstatus = 'okay';
       #
       # Download students data
       my $time_of_retrieval = time;
       my @tmp = &Apache::lonnet::currentdump($courseid,$sdom,$sname);
       if ((scalar(@tmp) > 0) && ($tmp[0] =~ /^error:/)) {
           &Apache::lonnet::logthis('error getting data for '.
                                    $sname.':'.$sdom.' in course '.$courseid.
                                    ':'.$tmp[0]);
           $returnstatus = 'error getting data';
           return $returnstatus;
       }
       if (scalar(@tmp) < 1) {
           return ('no data',undef);
       }
       my %student_data = @tmp;
       #
       # Remove all of the students data from the table
       my $dbh = &Apache::lonmysql::get_dbh();
       $dbh->do('DELETE FROM '.$performance_table.' WHERE student_id='.
                $student_id);
       $dbh->do('DELETE FROM '.$parameters_table.' WHERE student_id='.
                $student_id);
       #
       # Store away the data
       #
       my $starttime = Time::HiRes::time;
       my $elapsed = 0;
       my $rows_stored;
       my $store_parameters_command  = 'INSERT INTO '.$parameters_table.
           ' VALUES '."\n";
       my $num_parameters = 0;
       my $store_performance_command = 'INSERT INTO '.$performance_table.
           ' VALUES '."\n";
       return 'error' if (! defined($dbh));
       while (my ($current_symb,$param_hash) = each(%student_data)) {
           #
           # make sure the symb is set up properly
           my $symb_id = &get_symb_id($current_symb);
           #
           # Load data into the tables
           while (my ($parameter,$value) = each(%$param_hash)) {
               my $newstring;
               if ($parameter !~ /(timestamp|resource\.(.*)\.(solved|tries|awarded|award|awarddetail|previous))/) {
                   $newstring = "('".join("','",
                                          $symb_id,$student_id,
                                          $parameter)."',".
                                              $dbh->quote($value)."),\n";
                   $num_parameters ++;
                   if ($newstring !~ /''/) {
                       $store_parameters_command .= $newstring;
                       $rows_stored++;
                   }
               }
               next if ($parameter !~ /^resource\.(.*)\.solved$/);
               #
               my $part = $1;
               my $part_id = &get_part_id($part);
               next if (!defined($part_id));
               my $solved  = $value;
               my $tries   = $param_hash->{'resource.'.$part.'.tries'};
               my $awarded = $param_hash->{'resource.'.$part.'.awarded'};
               my $award   = $param_hash->{'resource.'.$part.'.award'};
               my $awarddetail = $param_hash->{'resource.'.$part.'.awarddetail'};
               my $timestamp = $param_hash->{'timestamp'};
               #
               $solved      = '' if (! defined($awarded));
               $tries       = '' if (! defined($tries));
               $awarded     = '' if (! defined($awarded));
               $award       = '' if (! defined($award));
               $awarddetail = '' if (! defined($awarddetail));
               $newstring = "('".join("','",$symb_id,$student_id,$part_id,
                                      $solved,$tries,$awarded,$award,
                                      $awarddetail,$timestamp)."'),\n";
               $store_performance_command .= $newstring;
               $rows_stored++;
           }
       }
       chop $store_parameters_command;
       chop $store_parameters_command;
       chop $store_performance_command;
       chop $store_performance_command;
       my $start = Time::HiRes::time;
       $dbh->do($store_parameters_command) if ($num_parameters>0);
       if ($dbh->err()) {
           &Apache::lonnet::logthis(' bigass insert error:'.$dbh->errstr());
           &Apache::lonnet::logthis('command = '.$store_parameters_command);
           $returnstatus = 'error: unable to insert parameters into database';
           return $returnstatus,\%student_data;
       }
       $dbh->do($store_performance_command);
       if ($dbh->err()) {
           &Apache::lonnet::logthis(' bigass insert error:'.$dbh->errstr());
           &Apache::lonnet::logthis('command = '.$store_performance_command);
           $returnstatus = 'error: unable to insert performance into database';
           return $returnstatus,\%student_data;
       }
       $elapsed += Time::HiRes::time - $start;
       #
       # Set the students update time
       &Apache::lonmysql::replace_row($updatetime_table,
                                      [$student,$time_of_retrieval]);
       return ($returnstatus,\%student_data);
   }
   
 $date:  A composite of the start and end date for this class for this  ################################################
 student.  Format:  end:start  ################################################
   
 $name:  the username:domain information  =pod
   
 $courseID: The course ID  =item &ensure_current_data()
   
 Output: None  Input: $sname, $sdom, $courseid
   
 *NOTE:  There is no return value, but if an error occurs a key is added to   Output: $status, $data
 the cache data with the value being the error message.  The key is   
 username:domain:error.  It will only exist if an error occurs.  
   
 =back  This routine ensures the data for a given student is up to date.  It calls
   &init_dbs() if the tables do not exist.  The $updatetime_table is queried
   to determine the time of the last update.  If the students data is out of
   date, &update_student_data() is called.  The return values from the call
   to &update_student_data() are returned.
   
 =cut  =cut
   
 sub ProcessStudentNamePIDSection {  ################################################
     my ($cache,$studentInformation,$section,$date,$name,$courseID,$status)=@_;  ################################################
     my ($studentName,$studentDomain) = split(/\:/,$name);  sub ensure_current_data {
       my ($sname,$sdom,$courseid) = @_;
     $cache->{$name.':username'}=$studentName;      my $status = 'okay';   # return value
     $cache->{$name.':domain'}=$studentDomain;      #
     $cache->{$name.':date'}=$date;      $courseid = $ENV{'request.course.id'} if (! defined($courseid));
       # 
     my ($checkForError)=keys(%$studentInformation);      # Clean out package variables
     if($checkForError =~ /^(con_lost|error|no_such_host)/i) {      &setup_table_names($courseid);
  $cache->{$name.':error'}=      #
     'Could not download student environment data.';      # if the tables do not exist, make them
  $cache->{$name.':fullname'}='';      my @CurrentTable = &Apache::lonmysql::tables_in_db();
  $cache->{$name.':id'}='';      my ($found_symb,$found_student,$found_part,$found_update,
     } else {          $found_performance,$found_parameters);
  $cache->{$name.':fullname'}=&ProcessFullName(      foreach (@CurrentTable) {
                                           $studentInformation->{'lastname'},          $found_symb        = 1 if ($_ eq $symb_table);
           $studentInformation->{'generation'},          $found_student     = 1 if ($_ eq $student_table);
           $studentInformation->{'firstname'},          $found_part        = 1 if ($_ eq $part_table);
                                           $studentInformation->{'middlename'});          $found_update      = 1 if ($_ eq $updatetime_table);
  $cache->{$name.':id'}=$studentInformation->{'id'};          $found_performance = 1 if ($_ eq $performance_table);
           $found_parameters  = 1 if ($_ eq $parameters_table);
     }      }
       if (!$found_symb        || !$found_update || 
     my $sec=&ProcessSection($section, $courseID, $status);          !$found_student     || !$found_part   ||
     if($sec != -1) {          !$found_performance || !$found_parameters) {
         $cache->{$name.':section'}=$sec;          if (&init_dbs($courseid)) {
     } else {              return 'error';
         $cache->{$name.':section'}='';          }
     }      }
       #
     return;      # Get the update time for the user
       my $updatetime = 0;
       my $modifiedtime = &Apache::lonnet::GetFileTimestamp
           ($sdom,$sname,$courseid.'.db',
            $Apache::lonnet::perlvar{'lonUsersDir'});
       #
       my $student = $sname.':'.$sdom;
       my @Result = &Apache::lonmysql::get_rows($updatetime_table,
                                                "student ='$student'");
       my $data = undef;
       if (@Result) {
           $updatetime = $Result[0]->[1];
       }
       if ($modifiedtime > $updatetime) {
           ($status,$data) = &update_student_data($sname,$sdom,$courseid);
       }
       return ($status,$data);
 }  }
   
   ################################################
   ################################################
   
 =pod  =pod
   
 =item &ProcessClassList()  =item &get_student_data_from_performance_cache()
   
 Taking the class list dumped from &DownloadPrerequisiteData(), all the   Input: $sname, $sdom, $symb, $courseid
 students and their non-class information is processed using the   
 &ProcessStudentInformation() function.  A date stamp is also recorded for  
 when the data was processed.  
   
 =over 4  Output: hash reference containing the data for the given student.
   If $symb is undef, all the students data is returned.
   
 Input: $cache, $classlist, $courseID, $ChartDB, $c  This routine is the heart of the local caching system.  See the description
   of $performance_table, $symb_table, $student_table, and $part_table.  The
   main task is building the MySQL request.  The tables appear in the request
   in the order in which they should be parsed by MySQL.  When searching
   on a student the $student_table is used to locate the 'student_id'.  All
   rows in $performance_table which have a matching 'student_id' are returned,
   with data from $part_table and $symb_table which match the entries in
   $performance_table, 'part_id' and 'symb_id'.  When searching on a symb,
   the $symb_table is processed first, with matching rows grabbed from 
   $performance_table and filled in from $part_table and $student_table in
   that order.  
   
 $cache: A hash pointer to store the data  Running 'EXPLAIN ' on the 'SELECT' statements generated can be quite 
   interesting, especially if you play with the order the tables are listed.  
   
 $classlist:  The hash of data collected about a student from   =cut
 &DownloadPrerequisteData().  The hash contains a list of students, a pointer   
 to a hash of student information for each student, and each student's section   
 number.  
   
 $courseID:  The course ID  ################################################
   ################################################
   sub get_student_data_from_performance_cache {
       my ($sname,$sdom,$symb,$courseid)=@_;
       my $student = $sname.':'.$sdom if (defined($sname) && defined($sdom));
       &setup_table_names($courseid);
       #
       # Return hash
       my $studentdata;
       #
       my $dbh = &Apache::lonmysql::get_dbh();
       my $request = "SELECT ".
           "d.symb,c.part,a.solved,a.tries,a.awarded,a.award,a.awarddetail,".
               "a.timestamp ";
       if (defined($student)) {
           $request .= "FROM $student_table AS b ".
               "LEFT JOIN $performance_table AS a ON b.student_id=a.student_id ".
               "LEFT JOIN $part_table AS c ON c.part_id = a.part_id ".
               "LEFT JOIN $symb_table AS d ON d.symb_id = a.symb_id ".
                   "WHERE student='$student'";
           if (defined($symb) && $symb ne '') {
               $request .= " AND d.symb=".$dbh->quote($symb);
           }
       } elsif (defined($symb) && $symb ne '') {
           $request .= "FROM $symb_table as d ".
               "LEFT JOIN $performance_table AS a ON d.symb_id=a.symb_id ".
               "LEFT JOIN $part_table    AS c ON c.part_id = a.part_id ".
               "LEFT JOIN $student_table AS b ON b.student_id = a.student_id ".
                   "WHERE symb='".$dbh->quote($symb)."'";
       }
       my $starttime = Time::HiRes::time;
       my $rows_retrieved = 0;
       my $sth = $dbh->prepare($request);
       $sth->execute();
       if ($sth->err()) {
           &Apache::lonnet::logthis("Unable to execute MySQL request:");
           &Apache::lonnet::logthis("\n".$request."\n");
           &Apache::lonnet::logthis("error is:".$sth->errstr());
           return undef;
       }
       foreach my $row (@{$sth->fetchall_arrayref}) {
           $rows_retrieved++;
           my ($symb,$part,$solved,$tries,$awarded,$award,$awarddetail,$time) = 
               (@$row);
           my $base = 'resource.'.$part;
           $studentdata->{$symb}->{$base.'.solved'}  = $solved;
           $studentdata->{$symb}->{$base.'.tries'}   = $tries;
           $studentdata->{$symb}->{$base.'.awarded'} = $awarded;
           $studentdata->{$symb}->{$base.'.award'}   = $award;
           $studentdata->{$symb}->{$base.'.awarddetail'} = $awarddetail;
           $studentdata->{$symb}->{'timestamp'} = $time if (defined($time) && $time ne '');
       }
       if (defined($symb) && $symb ne '') {
           $studentdata = $studentdata->{$symb};
       }
       return $studentdata;
   }
   
 $ChartDB:  The name of the cache database file.  ################################################
   ################################################
   
 $c:  The connection class used to determine if an abort has been sent to the   =pod
 browser  
   
 Output: @names  =item &get_current_state()
   
 @names:  An array of students whose information has been processed, and are to   Input: $sname,$sdom,$symb,$courseid
 be considered in an arbitrary order.  
   
 =back  Output: Described below
   
   Retrieve the current status of a students performance.  $sname and
   $sdom are the only required parameters.  If $symb is undef the results
   of an &Apache::lonnet::currentdump() will be returned.  
   If $courseid is undef it will be retrieved from the environment.
   
   The return structure is based on &Apache::lonnet::currentdump.  If
   $symb is unspecified, all the students data is returned in a hash of
   the form:
   ( 
     symb1 => { param1 => value1, param2 => value2 ... },
     symb2 => { param1 => value1, param2 => value2 ... },
   )
   
   If $symb is specified, a hash of 
   (
     param1 => value1, 
     param2 => value2,
   )
   is returned.
   
   If no data is found for $symb, or if the student has no performance data,
   an empty list is returned.
   
 =cut  =cut
   
 sub ProcessClassList {  ################################################
     my ($cache,$classlist,$courseID,$status,$c)=@_;  ################################################
     my @names=();  sub get_current_state {
       my ($sname,$sdom,$symb,$courseid,$forcedownload)=@_;
     foreach my $name (keys(%$classlist)) {      #
         if($name =~ /\:section/ || $name =~ /\:studentInformation/ ||      $courseid = $ENV{'request.course.id'} if (! defined($courseid));
            $name eq '') {      #
             next;      return () if (! defined($sname) || ! defined($sdom));
       #
       my ($status,$data) = &ensure_current_data($sname,$sdom,$courseid);
       #
       if (defined($data)) {
           if (defined($symb)) {
               return %{$data->{$symb}};
           } else {
               return %$data;
         }          }
         if($c->aborted()) {      } elsif ($status eq 'no data') {
             last;          return ();
       } else {
           if ($status ne 'okay' && $status ne '') {
               &Apache::lonnet::logthis('status = '.$status);
               return ();
         }          }
         push(@names,$name);          my $returnhash = &get_student_data_from_performance_cache($sname,$sdom,
         &ProcessStudentNamePIDSection($cache,                                                        $symb,$courseid);
                                      $classlist->{$name.':studentInformation'},          return %$returnhash if (defined($returnhash));
                                      $classlist->{$name.':section'},  
                                      $classlist->{$name},  
                                      $name,$courseID,$status);  
     }      }
       return ();
     # Time of download  
     $cache->{'time'}=localtime();  
   
     return @names;  
 }  }
   
   ################################################
   ################################################
   
 =pod  =pod
   
 =item &ProcessStudentData()  =item &get_problem_statistics()
   
   Gather data on a given problem.  The database is assumed to be 
   populated and all local caching variables are assumed to be set
   properly.  This means you need to call &ensure_current_data for
   the students you are concerned with prior to calling this routine.
   
 Takes the course data downloaded for a student in   Inputs: $students, $symb, $part, $courseid
 &DownloadStudentCourseInformation() and breaks it up into key value pairs  
 to be stored in the cached data.  The keys are comprised of the   
 $username:$domain:$keyFromCourseDatabase.  The student username:domain is  
 stored away signifying that the student's information has been downloaded and   
 can be reused from cached data.  
   
 =over 4  =over 4
   
 Input: $cache, $courseData, $name  =item $students is an array of hash references.  
   Each hash must contain at least the 'username' and 'domain' of a student.
   
 $cache: A hash pointer to store data  =item $symb is the symb for the problem.
   
 $courseData:  A hash pointer that points to the course data downloaded for a   =item $part is the part id you need statistics for
 student.  
   
 $name:  username:domain  =item $courseid is the course id, of course!
   
 Output: None  =back
   
 *NOTE:  There is no output, but an error message is stored away in the cache   Outputs: See the code for up to date information.  A hash reference is
 data.  This is checked in &FormatStudentData().  The key username:domain:error   returned.  The hash has the following keys defined:
 will only exist if an error occured.  The error is an error from   
 &DownloadStudentCourseInformation().  =over 4
   
   =item num_students The number of students attempting the problem
         
   =item tries The total number of tries for the students
         
   =item max_tries The maximum number of tries taken
         
   =item mean_tries The average number of tries
         
   =item num_solved The number of students able to solve the problem
         
   =item num_override The number of students whose answer is 'correct_by_override'
         
   =item deg_of_diff The degree of difficulty of the problem
         
   =item std_tries The standard deviation of the number of tries
         
   =item skew_tries The skew of the number of tries
   
   =item per_wrong The number of students attempting the problem who were not
   able to answer it correctly.
   
 =back  =back
   
 =cut  =cut
   
 sub ProcessStudentData {  ################################################
     my ($cache,$courseData,$name)=@_;  ################################################
   sub get_problem_statistics {
     my ($checkForError) = keys(%$courseData);      my ($students,$symb,$part,$courseid) = @_;
     if($checkForError =~ /^(con_lost|error|no_such_host)/i) {      return if (! defined($symb) || ! defined($part));
         $cache->{$name.':error'}='Could not download course data.';      $courseid = $ENV{'request.course.id'} if (! defined($courseid));
     } else {      #
         foreach my $key (keys (%$courseData)) {      my $symb_id = &get_symb_id($symb);
             $cache->{$name.':'.$key}=$courseData->{$key};      my $part_id = &get_part_id($part);
         }      my $stats_table = $courseid.'_problem_stats';
         if(defined($cache->{'NamesOfStudents'})) {      #
             $cache->{'NamesOfStudents'}.=':::'.$name;      my $dbh = &Apache::lonmysql::get_dbh();
         } else {      return undef if (! defined($dbh));
             $cache->{'NamesOfStudents'}=$name;      #
         }      # A) Number of Students attempting problem
       # B) Total number of tries of students attempting problem
       # C) Mod (largest number of tries for solving the problem)
       # D) Mean (average number of tries for solving the problem)
       # E) Number of students to solve the problem
       # F) Number of students to solve the problem by override
       # G) Number of students unable to solve the problem
       # H) Degree of difficulty : 1-(E+F)/B
       # I) Standard deviation of number of tries
       # J) Skew of tries: sqrt(sum(Xi-D)^3)/A
       #
       $dbh->do('DROP TABLE '.$stats_table);  # May return an error
       my $request = 
           'CREATE TEMPORARY TABLE '.$stats_table.
               ' SELECT student_id,solved,award,tries FROM '.$performance_table.
                   ' WHERE symb_id='.$symb_id.' AND part_id='.$part_id;
       if (defined($students)) {
           $request .= ' AND ('.
               join(' OR ', map {'student_id='.
                                     &get_student_id($_->{'username'},
                                                     $_->{'domain'})
                                     } @$students
                    ).')';
     }      }
   #    &Apache::lonnet::logthis($request);
     return;      $dbh->do($request);
       my ($num,$tries,$mod,$mean,$STD) = &execute_SQL_request
           ($dbh,
            'SELECT COUNT(*),SUM(tries),MAX(tries),AVG(tries),STD(tries) FROM '.
            $stats_table);
       my ($Solved) = &execute_SQL_request($dbh,'SELECT COUNT(tries) FROM '.
                                           $stats_table.
                                           " WHERE solved='correct_by_student'");
       my ($solved) = &execute_SQL_request($dbh,'SELECT COUNT(tries) FROM '.
                                           $stats_table.
                                           " WHERE solved='correct_by_override'");
       $num    = 0 if (! defined($num));
       $tries  = 0 if (! defined($tries));
       $mod    = 0 if (! defined($mod));
       $STD    = 0 if (! defined($STD));
       $Solved = 0 if (! defined($Solved));
       $solved = 0 if (! defined($solved));
       #
       my $DegOfDiff = 'nan';
       $DegOfDiff = 1-($Solved)/$tries if ($tries>0);
   
       my $SKEW = 'nan';
       my $wrongpercent = 0;
       if ($num > 0) {
           ($SKEW) = &execute_SQL_request($dbh,'SELECT SQRT(SUM('.
                                        'POWER(tries - '.$STD.',3)'.
                                        '))/'.$num.' FROM '.$stats_table);
           $wrongpercent=int(10*100*($num-$Solved+$solved)/$num)/10;
       }
       #
       $dbh->do('DROP TABLE '.$stats_table);  # May return an error
       return { num_students => $num,
                tries        => $tries,
                max_tries    => $mod,
                mean_tries   => $mean,
                std_tries    => $STD,
                skew_tries   => $SKEW,
                num_solved   => $Solved,
                num_override => $solved,
                per_wrong    => $wrongpercent,
                deg_of_diff  => $DegOfDiff }
 }  }
   
 # ----- END PROCESSING FUNCTIONS ---------------------------------------  sub execute_SQL_request {
       my ($dbh,$request)=@_;
 =pod  #    &Apache::lonnet::logthis($request);
       my $sth = $dbh->prepare($request);
       $sth->execute();
       my $row = $sth->fetchrow_arrayref();
       if (ref($row) eq 'ARRAY' && scalar(@$row)>0) {
           return @$row;
       }
       return ();
   }
   
 =head1 HELPER FUNCTIONS  
   
 These are just a couple of functions do various odd and end   ################################################
 jobs.  ################################################
   
 =cut  =pod
   
 # ----- HELPER FUNCTIONS -----------------------------------------------  =item &setup_table_names()
   
 =pod  input: course id
   
 =item &ProcessFullName()  output: none
   
 Takes lastname, generation, firstname, and middlename (or some partial  Cleans up the package variables for local caching.
 set of this data) and returns the full name version as a string.  Format  
 is Lastname generation, firstname middlename or a subset of this.  
   
 =cut  =cut
   
 sub ProcessFullName {  ################################################
     my ($lastname, $generation, $firstname, $middlename)=@_;  ################################################
     my $Str = '';  sub setup_table_names {
       my ($courseid) = @_;
     if($lastname ne '') {      if (! defined($courseid)) {
  $Str .= $lastname.' ';          $courseid = $ENV{'request.course.id'};
  if($generation ne '') {  
     $Str .= $generation;  
  } else {  
     chop($Str);  
  }  
  $Str .= ', ';  
  if($firstname ne '') {  
     $Str .= $firstname.' ';  
  }  
  if($middlename ne '') {  
     $Str .= $middlename;  
  } else {  
     chop($Str);  
     if($firstname eq '') {  
  chop($Str);  
     }  
  }  
     } else {  
  if($firstname ne '') {  
     $Str .= $firstname.' ';  
  }  
  if($middlename ne '') {  
     $Str .= $middlename.' ';  
  }  
  if($generation ne '') {  
     $Str .= $generation;  
  } else {  
     chop($Str);  
  }  
     }      }
       #
     return $Str;      if (! defined($current_course) || $current_course ne $courseid) {
           # Clear out variables
           $have_read_part_table = 0;
           undef(%ids_by_part);
           undef(%parts_by_id);
           $have_read_symb_table = 0;
           undef(%ids_by_symb);
           undef(%symbs_by_id);
           $have_read_student_table = 0;
           undef(%ids_by_student);
           undef(%students_by_id);
           #
           $current_course = $courseid;
       }
       #
       # Set up database names
       my $base_id = $courseid;
       $symb_table        = $base_id.'_'.'symb';
       $part_table        = $base_id.'_'.'part';
       $student_table     = $base_id.'_'.'student';
       $updatetime_table  = $base_id.'_'.'updatetime';
       $performance_table = $base_id.'_'.'performance';
       $parameters_table  = $base_id.'_'.'parameters';
       return;
 }  }
   
   ################################################
   ################################################
   
 =pod  =pod
   
 =item &TestCacheData()  =back
   
 Determine if the cache database can be accessed with a tie.  It waits up to  =item End of Local Data Caching Subroutines
 ten seconds before returning failure.  This function exists to help with  
 the problems with stopping the data download.  When an abort occurs and the  
 user quickly presses a form button and httpd child is created.  This  
 child needs to wait for the other to finish (hopefully within ten seconds).  
   
 =over 4  =cut
   
 Input: $ChartDB  ################################################
   ################################################
   
 $ChartDB: The name of the cache database to be opened  
   
 Output: -1, 0, 1  }
   ################################################
   ################################################
   
 -1: Couldn't tie database  =pod
  0: Use cached data  
  1: New cache database created, use that.  
   
 =back  =head3 Classlist Subroutines
   
 =cut  =item &get_classlist();
   
 sub TestCacheData {  Retrieve the classist of a given class or of the current class.  Student
     my ($ChartDB,$isRecalculate,$totalDelay)=@_;  information is returned from the classlist.db file and, if needed,
     my $isCached=-1;  from the students environment.
     my %testData;  
     my $tieTries=0;  Optional arguments are $cid, $cdom, and $cnum (course id, course domain,
   and course number, respectively).  Any omitted arguments will be taken 
   from the current environment ($ENV{'request.course.id'},
   $ENV{'course.'.$cid.'.domain'}, and $ENV{'course.'.$cid.'.num'}).
   
   Returns a reference to a hash which contains:
    keys    '$sname:$sdom'
    values  [$sdom,$sname,$end,$start,$id,$section,$fullname,$status]
   
   The constant values CL_SDOM, CL_SNAME, CL_END, etc. can be used
   as indices into the returned list to future-proof clients against
   changes in the list order.
   
     if(!defined($totalDelay)) {  =cut
         $totalDelay = 10;  
     }  
   
     if ((-e "$ChartDB") && (!$isRecalculate)) {  ################################################
  $isCached = 1;  ################################################
     } else {  
  $isCached = 0;  
     }  
   
     while($tieTries < $totalDelay) {  sub CL_SDOM     { return 0; }
         my $result=0;  sub CL_SNAME    { return 1; }
         if($isCached) {  sub CL_END      { return 2; }
             $result=tie(%testData,'GDBM_File',$ChartDB,&GDBM_READER,0640);  sub CL_START    { return 3; }
         } else {  sub CL_ID       { return 4; }
             $result=tie(%testData,'GDBM_File',$ChartDB,&GDBM_NEWDB,0640);  sub CL_SECTION  { return 5; }
   sub CL_FULLNAME { return 6; }
   sub CL_STATUS   { return 7; }
   
   sub get_classlist {
       my ($cid,$cdom,$cnum) = @_;
       $cid = $cid || $ENV{'request.course.id'};
       $cdom = $cdom || $ENV{'course.'.$cid.'.domain'};
       $cnum = $cnum || $ENV{'course.'.$cid.'.num'};
       my $now = time;
       #
       my %classlist=&Apache::lonnet::dump('classlist',$cdom,$cnum);
       while (my ($student,$info) = each(%classlist)) {
           if ($student =~ /^(con_lost|error|no_such_host)/i) {
               &Apache::lonnet::logthis('get_classlist error for '.$cid.':'.$student);
               return undef;
           }
           my ($sname,$sdom) = split(/:/,$student);
           my @Values = split(/:/,$info);
           my ($end,$start,$id,$section,$fullname);
           if (@Values > 2) {
               ($end,$start,$id,$section,$fullname) = @Values;
           } else { # We have to get the data ourselves
               ($end,$start) = @Values;
               $section = &Apache::lonnet::getsection($sdom,$sname,$cid);
               my %info=&Apache::lonnet::get('environment',
                                             ['firstname','middlename',
                                              'lastname','generation','id'],
                                             $sdom, $sname);
               my ($tmp) = keys(%info);
               if ($tmp =~/^(con_lost|error|no_such_host)/i) {
                   $fullname = 'not available';
                   $id = 'not available';
                   &Apache::lonnet::logthis('unable to retrieve environment '.
                                            'for '.$sname.':'.$sdom);
               } else {
                   $fullname = &ProcessFullName(@info{qw/lastname generation 
                                                          firstname middlename/});
                   $id = $info{'id'};
               }
               # Update the classlist with this students information
               if ($fullname ne 'not available') {
                   my $enrolldata = join(':',$end,$start,$id,$section,$fullname);
                   my $reply=&Apache::lonnet::cput('classlist',
                                                   {$student => $enrolldata},
                                                   $cdom,$cnum);
                   if ($reply !~ /^(ok|delayed)/) {
                       &Apache::lonnet::logthis('Unable to update classlist for '.
                                                'student '.$sname.':'.$sdom.
                                                ' error:'.$reply);
                   }
               }
         }          }
         if($result) {          my $status='Expired';
             last;          if(((!$end) || $now < $end) && ((!$start) || ($now > $start))) {
               $status='Active';
         }          }
         $tieTries++;          $classlist{$student} = 
         sleep 1;              [$sdom,$sname,$end,$start,$id,$section,$fullname,$status];
     }      }
     if($tieTries >= $totalDelay) {      if (wantarray()) {
         return -1;          return (\%classlist,['domain','username','end','start','id',
                                'section','fullname','status']);
       } else {
           return \%classlist;
     }      }
   
     untie(%testData);  
   
     return $isCached;  
 }  }
   
 #sub CheckStatus {  
 #    my ($name, $data, $status)=@_;  
   
 #    if($status eq 'Any') {  
 #        my $section = ' ';  
 #        foreach (split(':',$data->{$name.':Sections'})) {  
 #            if($data->{$name.':'.$_.'Status'} eq 'Active') {  
 #                return $_;  
 #            }  
 #            $section = $_;  
 #        }  
 #        return $_;  
 #    }  
   
 #    foreach (split(':',$data->{$name.':Sections'})) {  
 #        if($data->{$name.':'.$_.'Status'} eq $status) {  
 #            return $_;  
 #        }  
 #    }  
   
 #    foreach (split(':',$data->{$name.':Sections'})) {  
 #        if($data->{$name.':'.$_.'Status'} eq 'Any') {  
 #            return $_;  
 #        }  
 #    }  
   
 #    return 'not found';  
 #}  
   
 # ----- END HELPER FUNCTIONS --------------------------------------------  # ----- END HELPER FUNCTIONS --------------------------------------------
   
 1;  1;
 __END__  __END__
   
   
Removed from v.1.2  
changed lines
  Added in v.1.69

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