--- loncom/interface/Attic/lonchart.pm 2002/07/02 21:48:36 1.52 +++ loncom/interface/Attic/lonchart.pm 2002/07/08 13:38:52 1.55 @@ -1,7 +1,7 @@ # The LearningOnline Network with CAPA # (Publication Handler # -# $Id: lonchart.pm,v 1.52 2002/07/02 21:48:36 stredwic Exp $ +# $Id: lonchart.pm,v 1.55 2002/07/08 13:38:52 stredwic Exp $ # # Copyright Michigan State University Board of Trustees # @@ -48,6 +48,55 @@ =pod +=head1 NAME + +lonchart + +=head1 SYNOPSIS + +Quick display of students grades for a course in a compressed table format. + +=head1 DESCRIPTION + +This module process all student grades for a course and turns them into a +table like structure. + +This is part of the LearningOnline Network with CAPA project +described at http://www.lon-capa.org + +lonchart presents the user with a condensed view all a course's data. The +class title, the number of students, and the date for the last update of the +displayed data. There is also a legend that describes the chart values. + +For each valid grade for a student is linked with a submission record for that +problem. The ability to add and remove columns of data from the chart was +added for reducing the burden of having to scroll through large quantities +of data. The interface also allows for sorting of students by username, +last name, and section number of class. Active and expired students are +also available. + +The interface is controlled by three primary buttons: Recalculate Chart, +Refresh Chart, and Reset Selections. Recalculate Chart will update +the chart to the most recent data and keep the display settings for the chart +the same. Refresh Chart is used to redisplay the chart after selecting +different output formatting. Reset Selections is used to set the chart +display options back to default values. + +=head1 CODE LAYOUT DESCRIPTION + +The code is broken down into five components: formatting data for printing, +downloading data from servers, processing data, helper functions, +and the central processing functions. The module is broken into chunks +for each component. + +=head1 PACKAGES USED + + Apache::Constants qw(:common :http) + Apache::lonnet() + Apache::loncommon() + HTML::TokeParser + GDBM_File + =cut package Apache::lonchart; @@ -60,8 +109,44 @@ use HTML::TokeParser; use GDBM_File; #my $jr; + +=pod + +=head1 FORMAT DATA FOR PRINTING + +=cut + # ----- FORMAT PRINT DATA ---------------------------------------------- +=pod + +=item &FormatStudentInformation() + +This function produces a formatted string of the student's information: +username, domain, section, full name, and PID. + +=over 4 + +Input: $cache, $name, $studentInformation, $spacePadding + +$cache: This is a pointer to a hash that is tied to the cached data + +$name: The name and domain of the current student in name:domain format + +$studentInformation: A pointer to an array holding the names used to + +remove data from the hash. They represent the name of the data to be removed. + +$spacePadding: Extra spaces that represent the space between columns + +Output: $Str + +$Str: Formatted string. + +=back + +=cut + sub FormatStudentInformation { my ($cache,$name,$studentInformation,$spacePadding)=@_; my $Str=''; @@ -83,8 +168,42 @@ sub FormatStudentInformation { return $Str; } +=pod + +=item &FormatStudentData() + +First, FormatStudentInformation is called and prefixes the course information. +This function produces a formatted string of the student's course information. +Each column of data represents all the problems for a given sequence. For +valid grade data, a link is created for that problem to a submission record +for that problem. + +=over 4 + +Input: $name, $studentInformation, $spacePadding, $ChartDB + +$name: The name and domain of the current student in name:domain format + +$studentInformation: A pointer to an array holding the names used to +remove data from the hash. They represent +the name of the data to be removed. + +$spacePadding: Extra spaces that represent the space between columns + +$ChartDB: The name of the cached data database which will be tied to that +database. + +Output: $Str + +$Str: Formatted string that is an entire row of the chart. It is a +concatenation of student information and student course information. + +=back + +=cut + sub FormatStudentData { - my ($name,$coid,$studentInformation,$spacePadding,$ChartDB)=@_; + my ($name,$studentInformation,$spacePadding,$ChartDB)=@_; my ($sname,$sdom) = split(/\:/,$name); my $Str; my %CacheData; @@ -221,15 +340,43 @@ sub FormatStudentData { return $Str; } +=pod + +=item &CreateTableHeadings() + +This function generates the column headings for the chart. + +=over 4 + +Inputs: $CacheData, $studentInformation, $headings, $spacePadding + +$CacheData: pointer to a hash tied to the cached data database + +$studentInformation: a pointer to an array containing the names of the data +held in a column and is used as part of a key into $CacheData + +$headings: The names of the headings for the student information + +$spacePadding: The spaces to go between columns + +Output: $Str + +$Str: A formatted string of the table column headings. + +=back + +=cut + sub CreateTableHeadings { my ($CacheData,$studentInformation,$headings,$spacePadding)=@_; - my $Str='
';
+    my $Str='';
 
     for(my $index=0; $index<(scalar @$headings); $index++) {
         if(!&ShouldShowColumn($CacheData, 'heading'.$index)) {
             next;
         }
 
+        $Str .= '
';
 	my $data=$$headings[$index];
 	$Str .= $data;
 
@@ -238,6 +385,7 @@ sub CreateTableHeadings {
 	$Str .= (' 'x($CacheData->{$$studentInformation[$index].'Length'}-
                       $length));
 	$Str .= $spacePadding;
+        $Str .= '
'; } foreach my $sequence (split(/\:/,$CacheData->{'orderedSequences'})) { @@ -245,6 +393,7 @@ sub CreateTableHeadings { next; } + $Str .= '
';
         my $name = $CacheData->{$sequence.':title'};
 	$Str .= $name;
 	my @titleLength=split(//,$CacheData->{$sequence.':title'});
@@ -252,16 +401,46 @@ sub CreateTableHeadings {
                      (scalar @titleLength);
 	$Str .= (' 'x$leftover);
 	$Str .= $spacePadding;
+        $Str .= '
'; } - $Str .= 'Total Solved/Total Problems'; - $Str .= '
'; + $Str .= '
Total Solved/Total Problems
'; + $Str .= ''; return $Str; } +=pod + +=item &CreateColumnSelectionBox() + +If there are columns not being displayed then this selection box is created +with a list of those columns. When selections are made and the page +refreshed, the columns will be removed from this box and the column is +put back in the chart. If there is no columns to select, no row is added +to the interface table. + +=over 4 +Input: $CacheData, $headings + + +$CacheData: A pointer to a hash tied to the cached data + +$headings: An array of the names of the columns for the student information. +They are used for displaying which columns are missing. + +Output: $notThere + +$notThere: The string contains one row of a table. The first column has the +name of the selection box. The second contains the selection box +which has a size of four. + +=back + +=cut + sub CreateColumnSelectionBox { - my ($CacheData,$studentInformation,$headings,$spacePadding)=@_; + my ($CacheData,$headings)=@_; my $missing=0; my $notThere='Select column to view:'; @@ -295,28 +474,50 @@ sub CreateColumnSelectionBox { $notThere=''; } - return $notThere.''; + return $notThere.''; } +=pod + +=item &CreateColumnSelectors() + +This function generates the checkboxes above the column headings. The +column will be removed if the checkbox is unchecked. + +=over 4 + +Input: $CacheData, $headings + +$CacheData: A pointer to a hash tied to the cached data + +$headings: An array of the names of the columns for the student +information. They are used to know what are the student information columns + +Output: $present + +$present: The string contains the first row of a table. Each column contains +a checkbox which is left justified. Currently left justification is used +for consistency of location over the column in which it presides. + +=back + +=cut + sub CreateColumnSelectors { - my ($CacheData,$studentInformation,$headings,$spacePadding)=@_; + my ($CacheData,$headings)=@_; my $found=0; my ($name, $length, $position); - my $present='
';
+
+    my $present = '';
     for(my $index=0; $index<(scalar @$headings); $index++) {
         if(!&ShouldShowColumn($CacheData, 'heading'.$index)) {
             next;
         }
-        $name = $headings->[$index];
-        $length=$CacheData->{$$studentInformation[$index].'Length'};
-        $position=int($length/2);
-	$present .= (' 'x($position));
+        $present .= '';
         $present .= '';
-        $position+=2;
-	$present .= (' 'x($length-$position));
-	$present .= $spacePadding;
+        $present .= 'name="heading'.$index.'" />';
+        $present .= '';
         $found++;
     }
 
@@ -324,28 +525,44 @@ sub CreateColumnSelectors {
         if(!&ShouldShowColumn($CacheData, 'sequence'.$sequence)) {
             next;
         }
-        $name = $CacheData->{$sequence.':title'};
-        $length=$CacheData->{$sequence.':columnWidth'};
-        $position=int($length/2);
-	$present .= (' 'x($position));
+        $present .= '';
         $present .= '';
-        $position+=2;
-	$present .= (' 'x($length-$position));
-	$present .= $spacePadding;
+        $present .= 'name="sequence'.$sequence.'" />';
+        $present .= '';
         $found++;
     }
 
-    if($found) {
-        $present .= '
'; - $present = $present; - } else { + if(!$found) { $present = ''; } - return $present.''."\n";; + return $present.''."\n";; } +=pod + +=item &CreateForm() + +The interface for this module consists primarily of the controls in this +function. The student status selection (active, expired, any) is set here. +The sort buttons: username, last name, and section are set here. The +other buttons are Recalculate Chart, Refresh Chart, and Reset Selections. +These controls are in a table to clean up the interface. + +=over 4 + +Input: $CacheData + +$CacheData is a hash pointer to tied database for cached data. + +Output: $Ptr + +$Ptr is a string containing all the html for the above mentioned buttons. + +=back + +=cut + sub CreateForm { my ($CacheData)=@_; my $OpSel1=''; @@ -357,7 +574,6 @@ sub CreateForm { else { $OpSel1 = 'selected'; } my $Ptr .= '
'."\n"; - $Ptr .= ''; $Ptr .= '
'; $Ptr .= ''; $Ptr .= ''; $Str .= '

'.$ENV{'course.'.$ENV{'request.course.id'}.'.description'}; $Str .= '

'; @@ -420,8 +654,53 @@ sub StartDocument { # ----- END FORMAT PRINT DATA ------------------------------------------ +=pod + +=head1 DOWNLOAD INFORMATION + +This section contains all the files that get data from other servers +and/or itself. There is one function that has a call to get remote +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 + # ----- DOWNLOAD INFORMATION ------------------------------------------- +=pod + +=item &DownloadPrerequisiteData() + +Collects lastname, generation, middlename, firstname PID, and section for each +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 + +Input: $courseID, $c + +$courseID: The id of the course + +$c: The connection class that can determine if the browser has aborted. It +is used to short circuit this function so that it doesn't continue to +get information when there is no need. + +Output: \%classlist + +\%classlist: A pointer to a hash containing the following data: + +-A list of student name:domain (as keys) (known below as $name) + +-A hash pointer for each student containing lastname, generation, firstname, +middlename, and PID : Key is $name.'studentInformation' + +-A hash pointer to each students section data : Key is $name.section + +=back + +=cut + sub DownloadPrerequisiteData { my ($courseID, $c)=@_; my ($courseDomain,$courseNumber)=split(/\_/,$courseID); @@ -462,6 +741,30 @@ sub DownloadPrerequisiteData { return \%classlist; } +=pod + +=item &DownloadStudentCourseInformation() + +Dump of all the course information for a single student. There is no +pruning of data, it is all stored in a hash and returned. + +=over 4 + +Input: $name, $courseID + +$name: student name:domain + +$courseID: The id of the course + +Output: \%courseData + +\%courseData: A hash pointer to the raw data from the student's course +database. + +=back + +=cut + sub DownloadStudentCourseInformation { my ($name,$courseID)=@_; my ($studentName,$studentDomain) = split(/\:/,$name); @@ -474,7 +777,23 @@ sub DownloadStudentCourseInformation { # ----- END DOWNLOAD INFORMATION --------------------------------------- -# ----- END PROCESSING FUNCTIONS --------------------------------------- +=pod + +=head1 PROCESSING FUNCTIONS + +These functions process all the data for all the students. Also, they +are the only functions that access the cache database for writing. Thus +they are the only functions that cache data. The downloading and caching +were separated to reduce problems with stopping downloading then can't +tie hash to database later. + +=cut + +# ----- PROCESSING FUNCTIONS --------------------------------------- + +=pod + +=cut sub ProcessTopResourceMap { my ($ChartDB,$c)=@_; @@ -773,15 +1092,155 @@ sub ProcessClassList { $name,$courseID,$c); } + # Time of download + $CacheData{'time'}=localtime(); untie(%CacheData); } return @names; } -# ----- END PROCESSING FUNCTIONS --------------------------------------- +sub ProcessStudentData { + my ($courseData, $name, $ChartDB)=@_; -# ----- HELPER FUNCTIONS ----------------------------------------------- + my %CacheData; + if(tie(%CacheData,'GDBM_File',$ChartDB,&GDBM_WRCREAT,0640)) { + my ($checkForError) = keys(%$courseData); + if($checkForError =~ /^(con_lost|error|no_such_host)/i) { + $CacheData{$name.':error'}='Could not download course data.'; + } else { + foreach my $key (keys (%$courseData)) { + $CacheData{$name.':'.$key}=$courseData->{$key}; + } + if(defined($CacheData{'NamesOfStudents'})) { + $CacheData{'NamesOfStudents'}.=':::'.$name; + } else { + $CacheData{'NamesOfStudents'}=$name; + } + } + untie(%CacheData); + } + + return; +} + +=pod + +=item &ProcessFormData() + +Cache form data and set default form data (sort, status, heading.$number, +sequence.$number, reselect, reset, recalculate, and refresh) + +=over 4 + +Input: $ChartDB, $isCached + +$ChartDB: The name of the database for cached data + +$isCached: Is there already data for this course cached. This is used in +conjunction with the absence of all form data to know to display all selection +types. + +Output: None + +=back + +=cut + +sub ProcessFormData { + my ($ChartDB, $isCached)=@_; + my %CacheData; + + if(tie(%CacheData,'GDBM_File',$ChartDB,&GDBM_WRCREAT,0640)) { + if(defined($ENV{'form.sort'})) { + $CacheData{'form.sort'}=$ENV{'form.sort'}; + } elsif(!defined($CacheData{'form.sort'})) { + $CacheData{'form.sort'}='username'; + } + + # Ignore $ENV{'form.refresh'} + # Ignore $ENV{'form.recalculate'} + + if(defined($ENV{'form.status'})) { + $CacheData{'form.status'}=$ENV{'form.status'}; + } elsif(!defined($CacheData{'form.status'})) { + $CacheData{'form.status'}='Active'; + } + + my @headings=(); + my @sequences=(); + my $found=0; + foreach (keys(%ENV)) { + if(/form\.heading/) { + $found++; + push(@headings, $_); + } elsif(/form\.sequence/) { + $found++; + push(@sequences, $_); + } elsif(/form\./) { + $found++; + } + } + + if($found) { + $CacheData{'form.headings'}=join(":::",@headings); + $CacheData{'form.sequences'}=join(":::",@sequences); + } + + if(defined($ENV{'form.reselect'})) { + my @reselected = (ref($ENV{'form.reselect'}) ? + @{$ENV{'form.reselect'}} + : ($ENV{'form.reselect'})); + foreach (@reselected) { + if(/heading/) { + $CacheData{'form.headings'}.=":::".$_; + } elsif(/sequence/) { + $CacheData{'form.sequences'}.=":::".$_; + } + } + } + + if(defined($ENV{'form.reset'}) || (!$found && !$isCached)) { + $CacheData{'form.reset'}='true'; + $CacheData{'form.status'}='Active'; + $CacheData{'form.sort'}='username'; + $CacheData{'form.headings'}='ALLHEADINGS'; + $CacheData{'form.sequences'}='ALLSEQUENCES'; + } else { + $CacheData{'form.reset'}='false'; + } + + untie(%CacheData); + } + + return; +} + +=pod + +=item &SpaceColumns() + +Determines the width of all the columns in the chart. It is based on +the max of the data for that column and its header. + +=over 4 + +Input: $students, $studentInformation, $headings, $ChartDB + +$students: An array pointer to a list of students (username:domain) + +$studentInformatin: The type of data for the student information. It is +used as part of the key in $CacheData. + +$headings: The name of the student information columns. + +$ChartDB: The name of the cache database which is opened for read/write. + +Output: None - All data stored in cache. + +=back + +=cut sub SpaceColumns { my ($students,$studentInformation,$headings,$ChartDB)=@_; @@ -810,6 +1269,28 @@ sub SpaceColumns { return; } +# ----- END PROCESSING FUNCTIONS --------------------------------------- + +=pod + +=head1 HELPER FUNCTIONS + +These are just a couple of functions do various odd and end +jobs. + +=cut + +# ----- HELPER FUNCTIONS ----------------------------------------------- + +=pod + +=item &ProcessFullName() + +Takes lastname, generation, firstname, and middlename (or some partial +set of this data) and returns the full name version as a string. + +=cut + sub ProcessFullName { my ($lastname, $generation, $firstname, $middlename)=@_; my $Str = ''; @@ -850,6 +1331,31 @@ sub ProcessFullName { return $Str; } +=pod + +=item &SortStudents() + +Determines which students to display and in which order. Which are +displayed are determined by their status(active/expired). The order +is determined by the sort button pressed (default to username). The +type of sorting is username, lastname, or section. + +=over 4 + +Input: $students, $CacheData + +$students: A array pointer to a list of students (username:domain) + +$CacheData: A pointer to the hash tied to the cached data + +Output: @order + +@order: An ordered list of students (username:domain) + +=back + +=cut + sub SortStudents { my ($students,$CacheData)=@_; @@ -898,6 +1404,32 @@ sub SortStudents { return @order; } +=pod + +=item &TestCacheData() + +Determine if the cache database can be accessed with a tie. It waits up to +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 + +Input: $ChartDB + +$ChartDB: The name of the cache database to be opened + +Output: -1, 0, 1 + +-1: Couldn't tie database + 0: Use cached data + 1: New cache database created, use that. + +=back + +=cut + sub TestCacheData { my ($ChartDB)=@_; my $isCached=-1; @@ -932,29 +1464,26 @@ sub TestCacheData { return $isCached; } -sub ExtractStudentData { - my ($courseData, $name, $ChartDB)=@_; +=pod - my %CacheData; - if(tie(%CacheData,'GDBM_File',$ChartDB,&GDBM_WRCREAT,0640)) { - my ($checkForError) = keys(%$courseData); - if($checkForError =~ /^(con_lost|error|no_such_host)/i) { - $CacheData{$name.':error'}='Could not download course data.'; - } else { - foreach my $key (keys (%$courseData)) { - $CacheData{$name.':'.$key}=$courseData->{$key}; - } - if(defined($CacheData{'NamesOfStudents'})) { - $CacheData{'NamesOfStudents'}.=':::'.$name; - } else { - $CacheData{'NamesOfStudents'}=$name; - } - } - untie(%CacheData); - } +=item &ShouldShowColumn() - return; -} +Determine if a specified column should be shown on the chart. + +=over 4 + +Input: $cache, $test + +$cache: A pointer to the hash tied to the cached data + +$test: The form name of the column (heading.$headingIndex) or +(sequence.$sequenceIndex) + +Output: 0 (false), 1 (true) + +=back + +=cut sub ShouldShowColumn { my ($cache,$test)=@_; @@ -970,84 +1499,49 @@ sub ShouldShowColumn { return 1; } -# my $reselected=$cache->{'form.reselect'}; -# if($reselected=~/$test/) { -# return 1; -# } - return 0; } -sub ProcessFormData { - my ($ChartDB)=@_; - my %CacheData; +# ----- END HELPER FUNCTIONS -------------------------------------------- - if(tie(%CacheData,'GDBM_File',$ChartDB,&GDBM_WRCREAT,0640)) { - if(defined($ENV{'form.sort'})) { - $CacheData{'form.sort'}=$ENV{'form.sort'}; - } elsif(!defined($CacheData{'form.sort'})) { - $CacheData{'form.sort'}='username'; - } +=pod - # Ignore $ENV{'form.refresh'} - # Ignore $ENV{'form.recalculate'} +=head1 Handler and main function(BuildChart) - if(defined($ENV{'form.status'})) { - $CacheData{'form.status'}=$ENV{'form.status'}; - } elsif(!defined($CacheData{'form.status'})) { - $CacheData{'form.status'}='Active'; - } +The handler does some initial error checking and then passes the torch to +BuildChart. BuildChart calls all the appropriate functions to get the +job done. These are the only two functions that use print ($r). All other +functions return strings to BuildChart to be printed. - my @headings=(); - my @sequences=(); - my $found=0; - foreach (keys(%ENV)) { - if(/form\.heading/) { - $found++; - push(@headings, $_); - } elsif(/form\.sequence/) { - $found++; - push(@sequences, $_); - } elsif(/form\./) { - $found++; - } - } +=cut - if($found) { - $CacheData{'form.headings'}=join(":::",@headings); - $CacheData{'form.sequences'}=join(":::",@sequences); - } +=pod - if(defined($ENV{'form.reselect'})) { - my @reselected = (ref($ENV{'form.reselect'}) ? - @{$ENV{'form.reselect'}} - : ($ENV{'form.reselect'})); - foreach (@reselected) { - if(/heading/) { - $CacheData{'form.headings'}.=":::".$_; - } elsif(/sequence/) { - $CacheData{'form.sequences'}.=":::".$_; - } - } - } +=item &BuildChart() - if(defined($ENV{'form.reset'})) { - $CacheData{'form.reset'}='true'; - $CacheData{'form.status'}='Active'; - $CacheData{'form.sort'}='username'; - $CacheData{'form.headings'}='ALLHEADINGS'; - $CacheData{'form.sequences'}='ALLSEQUENCES'; - } else { - $CacheData{'form.reset'}='false'; - } + The following is the process that BuildChart goes through to create the + html document. - untie(%CacheData); - } + -Start the lonchart document + -Test for access to the CacheData + -Download class list information if not using cached data + -Sort students and print out table desciptive data + -Output student data + -If recalculating, store a list of students, but only if all their data was + downloaded. Leave off the others. + -End document - return; -} +=over 4 -# ----- END HELPER FUNCTIONS -------------------------------------------- +Input: $r + +$r: Used to print html + +Output: None + +=back + +=cut sub BuildChart { my ($r)=@_; @@ -1071,7 +1565,7 @@ sub BuildChart { $r->rflush(); return; } - &ProcessFormData($ChartDB); + &ProcessFormData($ChartDB, $isCached); # Download class list information if not using cached data my %CacheData; @@ -1106,28 +1600,36 @@ sub BuildChart { } # Sort students and print out table desciptive data + my $downloadTime=0; if(tie(%CacheData,'GDBM_File',$ChartDB,&GDBM_READER,0640)) { if(!$c->aborted()) { @students=&SortStudents(\@students,\%CacheData); } + if(defined($CacheData{'time'})) { $downloadTime=$CacheData{'time'}; } + else { $downloadTime=localtime(); } + if(!$c->aborted()) { $r->print('

'.$downloadTime.'

'); } if(!$c->aborted()) { $r->print('

'.(scalar @students). ' students

'); } if(!$c->aborted()) { $r->rflush(); } if(!$c->aborted()) { $r->print(&CreateLegend()); } + if(!$c->aborted()) { $r->print(''); } if(!$c->aborted()) { $r->print(&CreateForm(\%CacheData)); } if(!$c->aborted()) { $r->print(&CreateColumnSelectionBox( \%CacheData, - \@studentInformation, - \@headings, - $spacePadding)); } + \@headings)); } + if(!$c->aborted()) { $r->print('
'); } + if(!$c->aborted()) { $r->print('Note: Uncheck the boxes above a'); } + if(!$c->aborted()) { $r->print(' column to remove that column from'); } + if(!$c->aborted()) { $r->print(' the display.'); } + if(!$c->aborted()) { $r->print('aborted()) { $r->print('cellspacing="0">'); } if(!$c->aborted()) { $r->print(&CreateColumnSelectors( \%CacheData, - \@studentInformation, - \@headings, - $spacePadding)); } + \@headings)); } if(!$c->aborted()) { $r->print(&CreateTableHeadings( \%CacheData, \@studentInformation, \@headings, $spacePadding)); } + if(!$c->aborted()) { $r->print('
'); } if(!$c->aborted()) { $r->rflush(); } untie(%CacheData); } else { @@ -1135,6 +1637,7 @@ sub BuildChart { return; } + # Output student data my @updateStudentList = (); my $courseData; $r->print('
');
@@ -1147,13 +1650,15 @@ sub BuildChart {
             $courseData=&DownloadStudentCourseInformation($_, $cid);
             if($c->aborted()) { last; }
             push(@updateStudentList, $_);
-            &ExtractStudentData($courseData, $_, $ChartDB);
+            &ProcessStudentData($courseData, $_, $ChartDB);
         }
-        $r->print(&FormatStudentData($_, $cid, \@studentInformation,
+        $r->print(&FormatStudentData($_, \@studentInformation,
                                      $spacePadding, $ChartDB));
         $r->rflush();
     }
 
+    # If recalculating, store a list of students, but only if all their 
+    # data was downloaded.  Leave off the others.
     if(!$isCached && tie(%CacheData,'GDBM_File',$ChartDB,&GDBM_WRCREAT,0640)) {
         $CacheData{'NamesOfStudents'}=join(":::", @updateStudentList);
 #		    $CacheData{'NamesOfStudents'}=
@@ -1161,6 +1666,7 @@ sub BuildChart {
         untie(%CacheData);
     }
 
+    # End document
     $r->print('
'); $r->rflush(); @@ -1169,6 +1675,26 @@ sub BuildChart { # ================================================================ Main Handler +=pod + +=item &handler() + +The handler checks for permission to access the course data and for +initial header problem. Then it passes the torch to the work horse +function BuildChart. + +=over 4 + +Input: $r + +$r: This is the object that is used to print. + +Output: A Value (OK or HTTP_NOT_ACCEPTABLE) + +=back + +=cut + sub handler { my $r=shift; # $jr=$r;