[LON-CAPA-cvs] cvs: loncom /interface loncommunicate.pm lonmsg.pm

raeburn lon-capa-cvs@mail.lon-capa.org
Mon, 17 May 2004 19:00:46 -0000


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--raeburn1084820446
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raeburn		Mon May 17 15:00:46 2004 EDT

  Modified files:              
    /loncom/interface	lonmsg.pm loncommunicate.pm 
  Log:
  Course Coordinators and Instructors can schedule blocking periods for student display of e-mail.
  During a blocking period students will be unable to display LON-CAPA e-mail sent during the current
  blocking period. If Course Coodinators or Instructors need to contact students during this time, they
  should send a critical message (these will still be viewable). Note: because COM functions can be 
  used outside a course context, blocking prevents display of all messages sent to the student during the
  blocking period (including other courses).
  
  
--raeburn1084820446
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Content-Disposition: attachment; filename="raeburn-20040517150046.txt"

Index: loncom/interface/lonmsg.pm
diff -u loncom/interface/lonmsg.pm:1.100 loncom/interface/lonmsg.pm:1.101
--- loncom/interface/lonmsg.pm:1.100	Mon May 10 18:39:51 2004
+++ loncom/interface/lonmsg.pm	Mon May 17 15:00:45 2004
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Routines for messaging
 #
-# $Id: lonmsg.pm,v 1.100 2004/05/10 22:39:51 albertel Exp $
+# $Id: lonmsg.pm,v 1.101 2004/05/17 19:00:45 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -74,6 +74,18 @@
 interface, or other features they may wish to use in response to the
 student's query.
 
+=item * B<Blocking>: LON-CAPA can block display of e-mails that are 
+sent to a student during an online exam. A course coordinator or
+instructor can set an open and close date/time for scheduled online
+exams in a course. If a user uses the LON-CAPA internal messaging 
+system to display e-mails during the scheduled blocking event,  
+display of all e-mail sent during the blocking period will be 
+suppressed, and a message of explanation, including details of the 
+currently active blocking periods will be displayed instead. A user 
+who has a course coordinator or instructor role in a course will be
+unaffected by any blocking periods for the course, unless the user
+also has a student role in the course, AND has selected the student role.
+
 =back
 
 Users can ask LON-CAPA to forward messages to conventional e-mail
@@ -622,6 +634,7 @@
 }
 
 sub sortedmessages {
+    my ($blocked,$startblock,$endblock,$numblocked) = @_;
     my @messages = &Apache::lonnet::getkeys('nohist_email');
     #unpack the varibles and repack into temp for sorting
     my @temp;
@@ -631,7 +644,14 @@
 	    &Apache::lonmsg::unpackmsgid($msgid);
 	my @temp1 = ($sendtime,$shortsubj,$fromname,$fromdomain,$status,
 		     $msgid);
-	push @temp ,\@temp1;
+        # Check whether message was sent during blocking period.
+        if ($sendtime >= $startblock && ($sendtime <= $endblock && $endblock > 0) ) {
+            my $escid = &Apache::lonnet::unescape($msgid);
+            $$blocked{$escid} = 'ON';
+            $$numblocked ++;
+        } else { 
+            push @temp ,\@temp1;
+        }
     }
     #default sort
     @temp = sort  {$a->[0] <=> $b->[0]} @temp;    
@@ -672,7 +692,13 @@
 
 sub disall {
     my $r=shift;
-     $r->print(<<ENDDISHEADER);
+    my %blocked = ();
+    my %setters = ();
+    my $startblock;
+    my $endblock;
+    my $numblocked = 0;
+    &blockcheck(\%setters,\$startblock,\$endblock);
+    $r->print(<<ENDDISHEADER);
 <script>
     function checkall() {
 	for (i=0; i<document.forms.disall.elements.length; i++) {
@@ -726,7 +752,7 @@
      	$r->print('<a href = "?sortedby=revstatus">'.&mt('Status').'</th>');
     }
     $r->print('</tr>');
-    my @temp=sortedmessages();
+    my @temp=sortedmessages(\%blocked,$startblock,$endblock,\$numblocked);
     foreach (@temp){
 	my ($sendtime,$shortsubj,$fromname,$fromdomain,$status,$origID)= @$_;
 	if (($status ne 'deleted') && defined($sendtime) && $sendtime!~/error/) {
@@ -753,7 +779,15 @@
               '<a href="javascript:uncheckall()">'.&mt('Uncheck All').'</a><p>'.
 	      '<input type="hidden" name="sortedby" value="'.$ENV{'form.sortedby'}.'" />'.
               '<input type="submit" name="markeddel" value="'.&mt('Delete Checked').'" />'.
-              '</form></body></html>');
+              '</form>');
+    if ($numblocked > 0) {
+        my $beginblock = &Apache::lonlocal::locallocaltime($startblock);
+        my $finishblock = &Apache::lonlocal::locallocaltime($endblock);
+        $r->print('<br /><br />'.
+                  $numblocked.' '.&mt('message(s) is/are not viewable because display of LON-CAPA messages sent to you by other students between').' '.$beginblock.' '.&mt('and').' '.$finishblock.' '.&mt('is currently being blocked because of online exams.'));
+        &build_block_table($r,$startblock,$endblock,\%setters);
+    }
+    $r->print('</body></html>');
 }
 
 # ============================================================== Compose output
@@ -1030,15 +1064,391 @@
     }
 }
 
+# ----------------------------------------------------------- Blocking during exams
+
+sub examblock {
+    my ($r,$action) = @_;
+    unless ($ENV{'request.course.id'}) { return;}
+    unless (&Apache::lonnet::allowed('srm',$ENV{'request.course.id'})) { $r->print('Not allowed'); }
+    my %lt=&Apache::lonlocal::texthash(
+            'comb' => 'Communication Blocking',
+            'cbds' => 'Communication blocking during scheduled exams',
+            'desc' => 'You can use communication blocking to prevent students enrolled in this course from displaying LON-CAPA messages sent by other students during an online exam. As blocking of communication could potentially interrupt legitimate communication between students who are also both enrolled in a different LON-CAPA course, please be careful that you select the correct start and end times for your scheduled exam when setting or modifying these parameters.',
+             'mecb' => 'Modify existing communication blocking periods',
+             'ncbc' => 'No communication blocks currently stored'
+    );
+
+    my %ltext = &Apache::lonlocal::texthash(
+            'dura' => 'Duration',
+            'setb' => 'Set by',
+            'even' => 'Event',
+            'actn' => 'Action',
+            'star' => 'Start',
+            'endd' => 'End'
+    );
+
+    &printheader($r,'/adm/email?block=display',$lt{'comb'});
+    $r->print('<h3>'.$lt{'cbds'}.'</h3>');
+
+    if ($action eq 'store') {
+        &blockstore($r);
+    }
+
+    $r->print($lt{'desc'}.'<br /><br />
+               <form name="blockform" method="post" action="/adm/email?block=store">
+             ');
+
+    $r->print('<h4>'.$lt{'mecb'}.'</h4>');
+    my %records = ();
+    my $blockcount = 0;
+    my $parmcount = 0;
+    &get_blockdates(\%records,\$blockcount);
+    if ($blockcount > 0) {
+        $parmcount = &display_blocker_status($r,\%records,\%ltext);
+    } else {
+        $r->print($lt{'ncbc'}.'<br /><br />');
+    }
+    &display_addblocker_table($r,$parmcount,\%ltext);
+    $r->print(<<"END");
+<br />
+<input type="hidden" name="blocktotal" value="$blockcount" />
+<input type ="submit" value="Save Changes" />
+</form>
+</body>
+</html>
+END
+    return;
+}
+
+sub blockstore {
+    my $r = shift;
+    my %lt=&Apache::lonlocal::texthash(
+            'tfcm' => 'The following changes were made',
+            'cbps' => 'communication blocking period(s)',
+            'werm' => 'was/were removed',
+            'wemo' => 'was/were modified',
+            'wead' => 'was/were added',
+            'ncwm' => 'No changes were made.' 
+    );
+    my %adds = ();
+    my %removals = ();
+    my %cancels = ();
+    my $modtotal = 0;
+    my $canceltotal = 0;
+    my $addtotal = 0;
+    my %blocking = ();
+    $r->print('<h3>'.$lt{'head'}.'</h3>');
+    foreach (keys %ENV) {
+        if ($_ =~ m/^form\.modify_(\w+)$/) {
+            $adds{$1} = $1;
+            $removals{$1} = $1;
+            $modtotal ++;
+        } elsif ($_ =~ m/^form\.cancel_(\d+)$/) {
+            $cancels{$1} = $1;
+            unless ( defined($removals{$1}) ) {
+                $removals{$1} = $1;
+                $canceltotal ++;
+            }
+        } elsif ($_ =~ m/^form\.add_(\d+)$/) {
+            $adds{$1} = $1;
+            $addtotal ++;
+        }
+    }
+
+    foreach (keys %removals) {
+        my $hashkey = $ENV{'form.key_'.$_};
+        &Apache::lonnet::del('comm_block',["$hashkey"],
+                         $ENV{'course.'.$ENV{'request.course.id'}.'.domain'},
+                         $ENV{'course.'.$ENV{'request.course.id'}.'.num'}
+                         );
+    }
+    foreach (keys %adds) {
+        unless ( defined($cancels{$_}) ) {
+            my ($newstart,$newend) = &get_dates_from_form($_);
+            my $newkey = $newstart.'____'.$newend;
+            $blocking{$newkey} = $ENV{'user.name'}.'@'.$ENV{'user.domain'}.':'.$ENV{'form.title_'.$_};
+        }
+    }
+    if ($addtotal + $modtotal > 0) {
+        &Apache::lonnet::put('comm_block',\%blocking,
+                     $ENV{'course.'.$ENV{'request.course.id'}.'.domain'},
+                     $ENV{'course.'.$ENV{'request.course.id'}.'.num'}
+                     );
+    }
+    my $chgestotal = $canceltotal + $modtotal + $addtotal;
+    if ($chgestotal > 0) {
+        $r->print($lt{'tfcm'}.'<ul>');
+        if ($canceltotal > 0) {
+            $r->print('<li>'.$canceltotal.' '.$lt{'cbps'},' '.$lt{'werm'}.'</li>');
+        }
+        if ($modtotal > 0) {
+            $r->print('<li>'.$modtotal.' '.$lt{'cbps'},' '.$lt{'wemo'}.'</li>');
+        }
+        if ($addtotal > 0) {
+            $r->print('<li>'.$addtotal.' '.$lt{'cbps'},' '.$lt{'wead'}.'</li>');
+        }
+        $r->print('</ul>');
+    } else {
+        $r->print($lt{'ncwm'});
+    }
+    $r->print('<br />');
+    return;
+}
+
+sub get_dates_from_form {
+    my $item = shift;
+    my $startdate = &Apache::lonhtmlcommon::get_date_from_form('startdate_'.$item);
+    my $enddate   = &Apache::lonhtmlcommon::get_date_from_form('enddate_'.$item);
+    return ($startdate,$enddate);
+}
+
+sub get_blockdates {
+    my ($records,$blockcount) = @_;
+    $$blockcount = 0;
+    %{$records} = &Apache::lonnet::dump('comm_block',
+                         $ENV{'course.'.$ENV{'request.course.id'}.'.domain'},
+                         $ENV{'course.'.$ENV{'request.course.id'}.'.num'}
+                         );
+    $$blockcount = keys %{$records};
+                                                                                                             
+    foreach (keys %{$records}) {
+        if ($_ eq 'error: 2 tie(GDBM) Failed while attempting dump') {
+            $$blockcount = 0;
+            last;
+        }
+    }
+}
+
+sub display_blocker_status {
+    my ($r,$records,$ltext) = @_;
+    my $parmcount = 0;
+    my @bgcols = ("#eeeeee","#dddddd");
+    my $function = &Apache::loncommon::get_users_function();
+    my $color = &Apache::loncommon::designparm($function.'.tabbg',
+                                                    $ENV{'user.domain'});
+    my %lt = &Apache::lonlocal::texthash(
+        'modi' => 'Modify',
+        'canc' => 'Cancel',
+    );
+    $r->print(<<"END");
+<table border="0" cellpadding="0" cellspacing="0">
+ <tr>
+  <td width="100%" bgcolor="#000000">
+   <table width="100%" border="0" cellpadding="1" cellspacing="0">
+    <tr>
+     <td width="100%" bgcolor="#000000">
+      <table border="0" cellpadding="3" cellspacing="3" bgcolor="#FFFFFF">
+       <tr bgcolor="$color">
+        <td><b>$$ltext{'dura'}</b></td>
+        <td><b>$$ltext{'setb'}</b></td>
+        <td><b>$$ltext{'even'}</b></td>
+        <td><b>$$ltext{'actn'}?</b></td>
+       </tr>
+END
+    foreach (sort keys %{$records}) {
+        my $iter = $parmcount%2;
+        my $onchange = 'onFocus="javascript:window.document.forms['.
+                       "'blockform'].elements['modify_".$parmcount."'].".
+                       'checked=true;"';
+        my ($start,$end) = split/____/,$_;
+        my $startform = &Apache::lonhtmlcommon::date_setter('blockform','startdate_'.$parmcount,$start,$onchange);
+        my $endform = &Apache::lonhtmlcommon::date_setter('blockform','enddate_'.$parmcount,$end,$onchange);
+        my ($setter,$title) = split/:/,$$records{$_};
+        my ($setuname,$setudom) = split/@/,$setter;
+        my $settername = &Apache::loncommon::plainname($setuname,$setudom);
+        $r->print(<<"END");
+       <tr bgcolor="$bgcols[$iter]">
+        <td>$$ltext{'star'}:&nbsp;$startform<br/>$$ltext{'endd'}:&nbsp;&nbsp;$endform</td>
+        <td>$settername</td>
+        <td><input type="text" name="title_$parmcount" size="15" value="$title"/><input type="hidden" name="key_$parmcount" value="$_"></td>
+        <td>$lt{'modi'}?&nbsp;<input type="checkbox" name="modify_$parmcount"/><br />$lt{'canc'}?&nbsp;&nbsp;<input type="checkbox" name="cancel_$parmcount"/>
+       </tr>
+END
+        $parmcount ++;
+    }
+    $r->print(<<"END");
+      </table>
+     </td>
+    </tr>
+   </table>
+  </td>
+ </tr>
+</table>
+<br />
+<br />
+END
+    return $parmcount;
+}
+
+sub display_addblocker_table {
+    my ($r,$parmcount,$ltext) = @_;
+    my $start = time;
+    my $end = $start + (60 * 60 * 2); #Default is an exam of 2 hours duration.
+    my $onchange = 'onFocus="javascript:window.document.forms['.
+                   "'blockform'].elements['add_".$parmcount."'].".
+                   'checked=true;"';
+    my $startform = &Apache::lonhtmlcommon::date_setter('blockform','startdate_'.$parmcount,$start,$onchange);
+    my $endform = &Apache::lonhtmlcommon::date_setter('blockform','enddate_'.$parmcount,$end,$onchange);
+    my $function = &Apache::loncommon::get_users_function();
+    my $color = &Apache::loncommon::designparm($function.'.tabbg',
+                                                    $ENV{'user.domain'});
+    my %lt = &Apache::lonlocal::texthash(
+        'addb' => 'Add block',
+        'exam' => 'e.g., Exam 1',
+        'addn' => 'Add new communication blocking periods'
+    );
+    $r->print(<<"END");
+<h4>$lt{'addn'}</h4> 
+<table border="0" cellpadding="0" cellspacing="0">
+ <tr>
+  <td width="100%" bgcolor="#000000">
+   <table width="100%" border="0" cellpadding="1" cellspacing="0">
+    <tr>
+     <td width="100%" bgcolor="#000000">
+      <table border="0" cellpadding="3" cellspacing="3" bgcolor="#FFFFFF">
+       <tr bgcolor="#CCCCFF">
+        <td><b>$$ltext{'dura'}</b></td>
+        <td><b>$$ltext{'even'} $lt{'exam'}</b></td>
+        <td><b>$$ltext{'actn'}?</b></td>
+       </tr>
+       <tr bgcolor="#eeeeee">
+        <td>$$ltext{'star'}:&nbsp;$startform<br />$$ltext{'endd'}:&nbsp;&nbsp;$endform</td>
+        <td><input type="text" name="title_$parmcount" size="15" value=""/></td>
+        <td>$lt{'addb'}?&nbsp;<input type="checkbox" name="add_$parmcount" value="1"/></td>
+       </tr>
+      </table>
+     </td>
+    </tr>
+   </table>
+  </td>
+ </tr>
+</table>
+END
+    return;
+}
+
+sub blockcheck {
+    my ($setters,$startblock,$endblock) = @_;
+    # Retrieve active student roles and active course coordinator/instructor roles
+    my @livecses = ();
+    my @staffcses = ();
+    $$startblock = 0;
+    $$endblock = 0;
+    foreach (keys %ENV) {
+        if ($_ =~ m-^user\.role\.(st|cc|in)\./(.+)$-) {
+            my $role = $1;
+            my $cse = $2;
+            $cse =~ s|/|_|;
+            if ($ENV{$_} =~ m/^(\d*)\.(\d*)$/) {
+                unless (($2 > 0 && $2 < time) || ($1 > time)) {
+                    if ($role eq 'st') {
+                        push @livecses, $cse;
+                    } else {
+                        unless (grep/^$cse$/,@staffcses) {
+                            push @staffcses, $cse;
+                        }
+                    }
+                }
+            }
+        } elsif ($_ =~ m-user\.role\.cr/(\w+)/(\w+)/([^/]+)\./(.+)$- ) { 
+            my $rolepriv = $ENV{'user.role..rolesdef_'.$3};
+        }
+    }
+    # Retrieve blocking times and identity of blocker for active courses for students.
+    if (@livecses > 0) {
+        foreach my $cse (@livecses) {
+            my ($cdom,$crs) = split/_/,$cse;
+            if ( (grep/^$cse$/,@staffcses) && ($ENV{'request.role'} !~ m-^st\./$cdom/$crs$-) ) {
+                next;
+            } else {
+                %{$$setters{$cse}} = ();
+                @{$$setters{$cse}{'staff'}} = ();
+                @{$$setters{$cse}{'times'}} = ();
+                my %records = &Apache::lonnet::dump('comm_block',$cdom,$crs);
+                foreach (keys %records) {
+                    if ($_ =~ m/^(\d+)____(\d+)$/) {
+                        if ($1 <= time && $2 >= time) {
+                            my ($staff,$title) = split/:/,$records{$_};
+                            push @{$$setters{$cse}{'staff'}}, $staff;
+                            push @{$$setters{$cse}{'times'}}, $_;
+                            if ( ($$startblock == 0) || ($$startblock > $1) ) {
+                                $$startblock = $1;
+                            }
+                            if ( ($$endblock == 0) || ($$endblock < $2) ) {
+                                $$endblock = $2;
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+
+sub build_block_table {
+    my ($r,$startblock,$endblock,$setters) = @_;
+    my $function = &Apache::loncommon::get_users_function();
+    my $color = &Apache::loncommon::designparm($function.'.tabbg',
+                                                    $ENV{'user.domain'});
+    my %lt = &Apache::lonlocal::texthash(
+        'cacb' => 'Currently active communication blocks',
+        'cour' => 'Course',
+        'dura' => 'Duration',
+        'blse' => 'Block set by'
+    ); 
+    $r->print(<<"END");
+<br /<br />$lt{'cacb'}:<br /><br />
+<table border="0" cellpadding="0" cellspacing="0">
+ <tr>
+  <td width="100%" bgcolor="#000000">
+   <table width="100%" border="0" cellpadding="1" cellspacing="0">
+    <tr>
+     <td width="100%" bgcolor="#000000">
+      <table border="0" cellpadding="3" cellspacing="3" bgcolor="#FFFFFF">
+       <tr bgcolor="$color">
+        <td><b>$lt{'cour'}</b></td>
+        <td><b>$lt{'dura'}</b></td>
+        <td><b>$lt{'blse'}</b></td>
+       </tr>
+END
+    foreach (keys %{$setters}) {
+        my %courseinfo=&Apache::lonnet::coursedescription($_);
+        for (my $i=0; $i<@{$$setters{$_}{staff}}; $i++) {
+            my ($uname,$udom) = split/\@/,$$setters{$_}{staff}[$i];
+            my $fullname = &Apache::loncommon::plainname($uname,$udom);
+            my ($openblock,$closeblock) = split/____/,$$setters{$_}{times}[$i];
+            $openblock = &Apache::lonlocal::locallocaltime($openblock);
+            $closeblock= &Apache::lonlocal::locallocaltime($closeblock);
+            $r->print('<tr><td>'.$courseinfo{'description'}.'</td>'.
+                      '<td>'.$openblock.' to '.$closeblock.'</td>'.
+                      '<td>'.$fullname.' ('.$uname.'@'.$udom.
+                      ')</td></tr>');
+        }
+    }
+    $r->print('</table></td></tr></table></td></tr></table>');
+}
+
 # ----------------------------------------------------------- Display a message
 
 sub displaymessage {
     my ($r,$msgid)=@_;
+    my %blocked = ();
+    my %setters = ();
+    my $startblock = 0;
+    my $endblock = 0;
+    my $numblocked = 0;
+# info to generate "next" and "previous" buttons and check if message is blocked
+    &blockcheck(\%setters,\$startblock,\$endblock);
+    my @messages=&sortedmessages(\%blocked,$startblock,$endblock,\$numblocked);
+    if ( $blocked{$msgid} eq 'ON' ) {
+        &printheader($r,'/adm/email',&mt('Display a Message'));
+        $r->print(&mt('You attempted to display a message that is currently blocked because you are enrolled in one or more courses for which there is an ongoing online exam.'));
+        &build_block_table($r,$startblock,$endblock,\%setters);
+        return;
+    }
     &statuschange($msgid,'read');
     my %message=&Apache::lonnet::get('nohist_email',[$msgid]);
     my %content=&unpackagemsg($message{$msgid});
-# info to generate "next" and "previous" buttons
-    my @messages=&sortedmessages();
     my $counter=0;
     $r->print('<pre>');
     my $escmsgid=&Apache::lonnet::escape($msgid);
@@ -1132,10 +1542,12 @@
     &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},
         ['display','replyto','forward','markread','markdel','markunread',
          'sendreply','compose','sendmail','critical','recname','recdom',
-         'recordftf','sortedby']);
+         'recordftf','sortedby','block']);
     $sqs='&sortedby='.$ENV{'form.sortedby'};
 # ------------------------------------------------------ They checked for email
-    &Apache::lonnet::put('email_status',{'recnewemail'=>0});
+    unless ($ENV{'form.block'}) {
+        &Apache::lonnet::put('email_status',{'recnewemail'=>0});
+    }
 
 # ----------------------------------------------------------------- Breadcrumbs
 
@@ -1194,6 +1606,8 @@
 	&compout($r,'','',$ENV{'form.compose'});
     } elsif ($ENV{'form.recordftf'}) {
 	&facetoface($r,$ENV{'form.recordftf'});
+    } elsif ($ENV{'form.block'}) {
+        &examblock($r,$ENV{'form.block'});
     } elsif ($ENV{'form.sendmail'}) {
 	my $sendstatus='';
 	if ($ENV{'form.send'}) {
Index: loncom/interface/loncommunicate.pm
diff -u loncom/interface/loncommunicate.pm:1.21 loncom/interface/loncommunicate.pm:1.22
--- loncom/interface/loncommunicate.pm:1.21	Fri Mar 26 14:35:59 2004
+++ loncom/interface/loncommunicate.pm	Mon May 17 15:00:46 2004
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # Communicate
 #
-# $Id: loncommunicate.pm,v 1.21 2004/03/26 19:35:59 www Exp $
+# $Id: loncommunicate.pm,v 1.22 2004/05/17 19:00:46 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -50,7 +50,9 @@
 'da' => 'Date',
 'us' => 'Username',
 'op' => 'Open',
-'do' => 'Domain'
+'do' => 'Domain',
+'cbs' => 'Configure blocking of student communication during exams' 
+
 );
     my %help=();
     foreach ('Course_Face_To_Face_Records,Course_Critical_Message',
@@ -82,7 +84,9 @@
 <tr><td bgcolor="#FFFFAA">
 <b><a href="/adm/email?recordftf=query">$lt{'unr'}</a></b>$help{'Course_Face_To_Face_Records,Course_Critical_Message'}
 </td></tr>
-
+<tr><td bgcolor="#FFFFAA">
+  <b><a href="/adm/email?block=display">$lt{'cbs'}</a>
+</td></tr>
 END
     }
     $r->print('</table>');
@@ -91,21 +95,34 @@
                              $ENV{'user.name'}.':nohist_email',
                              $ENV{'user.home'}));
     my @newmsgs;
+    my %setters = ();
+    my $startblock = 0;
+    my $endblock = 0;
+    my %blocked = ();
+    my $numblocked = 0;
+    # Check for blocking of display because of scheduled online exams.
+    &Apache::lonmsg::blockcheck(\%setters,\$startblock,\$endblock);
     foreach (@msgids) {
         my ($sendtime,$shortsubj,$fromname,$fromdom,$status)=
 	    &Apache::lonmsg::unpackmsgid($_);
-       if (defined($sendtime) && $sendtime!~/error/) {
-        $sendtime = &Apache::lonlocal::locallocaltime($sendtime);
-        if ($status eq 'new') {
-            push @newmsgs, { 
-                msgid    => $_,
-                sendtime => $sendtime,
-                shortsub => &Apache::lonnet::unescape($shortsubj),
-                from     => $fromname,
-                fromdom  => $fromdom 
+        if (defined($sendtime) && $sendtime!~/error/) {
+            my $numsendtime = $sendtime;
+            $sendtime = &Apache::lonlocal::locallocaltime($sendtime);
+            if ($status eq 'new') {
+                if ($numsendtime >= $startblock && ($numsendtime <= $endblock && $endblock > 0) ) {
+                    $blocked{$_} = 'ON';
+                    $numblocked ++;
+                } else {
+                    push @newmsgs, { 
+                        msgid    => $_,
+                        sendtime => $sendtime,
+                        shortsub => &Apache::lonnet::unescape($shortsubj),
+                        from     => $fromname,
+                        fromdom  => $fromdom 
+                        }
                 }
+            }
         }
-       }
     }
     if ($#newmsgs >= 0) {
         $r->print(<<TABLEHEAD);
@@ -124,8 +141,22 @@
             $r->print("</td></tr>");
         }
         $r->print('</table></body></html>');
-    } else {
+    } elsif ($numblocked == 0) {
         $r->print("<h3>".&mt('You have no unread messages')."</h3>");
+    }
+    if ($numblocked > 0) {
+        my $beginblock = &Apache::lonlocal::locallocaltime($startblock);
+        my $finishblock = &Apache::lonlocal::locallocaltime($endblock);
+        if ($numblocked == 1) {
+            $r->print("<h3>".&mt('You have').' '.$numblocked.' '.&mt('blocked unread message').".</h3>");
+            $r->print(&mt('This message is not viewable because').' ');
+        } else {
+            $r->print("<h3>".&mt('You have').' '.$numblocked.' '.&mt('blocked unread messages').".</h3>");
+            $r->print(&mt('These').' '.$numblocked.' '.&mt('messages are not viewable because '));
+        }
+        $r->print(
+&mt('display of LON-CAPA messages sent to you by other students between').' '.$beginblock.' '.&mt('and').' '.$finishblock.' '.&mt('is currently being blocked because of online exams').'.');
+        &Apache::lonmsg::build_block_table($r,$startblock,$endblock,\%setters);
     }
 }
 

--raeburn1084820446--