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

[raeburn]

raeburn		Thu Jul 20 11:51:12 2006 EDT

  Modified files:              
    /loncom/interface	groupboards.pm 
  Log:
  Creating group bulletin boards now uses lonnet::newput() to lock a record in groupboards.db file to ensure a unique numeric id used for the url.  New group id is stored in db file in combination with groupname as a new key.
  
  
Index: loncom/interface/groupboards.pm
diff -u loncom/interface/groupboards.pm:1.7 loncom/interface/groupboards.pm:1.8
--- loncom/interface/groupboards.pm:1.7	Mon Jul 17 10:52:00 2006
+++ loncom/interface/groupboards.pm	Thu Jul 20 11:51:10 2006
@@ -77,7 +77,7 @@
     }
     my %curr_groups = &Apache::longroup::coursegroups($cdom,$cnum,$group);
     if (!defined($curr_groups{$group})) {
-        $earlyout = &mt('Invalid [_1]',$gpterm);
+        $earlyout = &mt('Invalid group');
         $r->print(&display_error($cdom,$cnum,$group,$description,$gpterm,
                                  $ucgpterm,$bodytitle,$earlyout,$refarg));
         return OK;
@@ -103,7 +103,7 @@
         if (($can_create) || (&Apache::lonnet::allowed('mdg',$env{'request.course.id'}))) {
             $r->print(&boards_header($cdom,$cnum,$group,$description,$gpterm,
                                      $ucgpterm,$bodytitle,$refarg));
-            my ($outcome,$newurl,$bbtitle) = 
+            my ($outcome,$newurl,$bbtitle,$dellockoutcome) = 
 		&create_board($cdom,$cnum,$group,$env{'form.newbul'});
             if ($outcome eq 'ok') {
                 my ($furl,$ferr)= &Apache::lonuserstate::readmap($cdom.'/'.$cnum);
@@ -115,6 +115,9 @@
                           '<a href="/adm/groupboards?group='.$group.'&amp;'.
                           $refarg.'">'.&mt('View all group discussion boards').
                           '</a></td></tr></table>');
+                if ($dellockoutcome ne 'ok') {
+                    $r->print(&mt('There was a problem removing a lockfile for the group ([_1]). This may prevent creation of additional bulletin boards in this group.  Please contact the system administrator for your LON-CAPA domain.'));
+                }
             } else {
                 $r->print(&mt('There was a problem creating the new discussion board - [_1]','<span class="LC_error">'.$outcome.'</span>').'<br /><a href="/adm/groupboards?group='.$group.'">'.
                          &mt('Return to discussion boards').'</a>');
@@ -130,8 +133,7 @@
 function makebulboard() {
    var title=prompt('Discussion Board Title');
    if (title) {
-    this.document.forms.newbb.newbul.value=
-        title+'=/adm/$cdom/$cnum/$now/bulletinboard';
+    this.document.forms.newbb.newbul.value=title;
     this.document.forms.newbb.submit();
    }
 }
@@ -173,16 +175,59 @@
 }
 
 sub create_board {
-    my ($cdom,$cnum,$group,$newboard) = @_;
-    my ($bbtitle,$newurl)=split(/\=/,$newboard);
-    my $outcome;
-    my ($boardid) = ($newurl =~ m-/adm/\Q$cdom\E/\Q$cnum\E/(\d+)/bulletinboard-);
-    if (!$boardid) {
-        $outcome = ('error: the URL for new board was invalid');
-        return ($outcome,$newurl,$bbtitle);
-    }
+    my ($cdom,$cnum,$group,$bbtitle) = @_;
+    my ($outcome,$boardid,$newurl);
     $bbtitle=&unescape($bbtitle);
+    # get lock on nohist_groupboards file
+    my $lockhash = {
+                  $group."\0".'locked_boardids' => $env{'user.name'}.
+                                                       ':'.$env{'user.domain'},
+                   };
+    my $tries = 0;
+    my $gotlock = &Apache::lonnet::newput('nohist_groupboards',$lockhash,$cdom,$cnum);
+    my $dellockoutcome;
+    while (($gotlock ne 'ok') && $tries <3) {
+        $tries ++;
+        sleep 1;
+        $gotlock = &Apache::lonnet::newput('nohist_groupboards',$lockhash,$cdom,$cnum);
+    }
+    if ($gotlock eq 'ok') {
+       my %curr_boards = &Apache::lonnet::dump('nohist_groupboards',$cdom,$cnum,$group);
+       $boardid = time;
+       my $idtries = 0;
+       while(exists($curr_boards{$group."\0".$boardid}) && $idtries < 20) {
+           $boardid ++;
+           $idtries ++;
+       }
+       if (!exists($curr_boards{$group."\0".$boardid})) {
+           my %new_board = (
+                          $group."\0".$boardid => $env{'user.name'}.':'.
+                                                  $env{'user.domain'},
+           );
+           my $putresult = &Apache::lonnet::put('nohist_groupboards',\%new_board,
+                                                $cdom,$cnum);
+           if ($putresult ne 'ok') {
+               $outcome = 'error storing new board: '.$putresult;
+           } else {
+               $newurl = '/adm/'.$cdom.'/'.$cnum.'/'.$boardid.
+                         '/bulletinboard';
+           }
+       } else {
+            $outcome = ('error: no unique ID for the new board available.');
+       }
+       #  remove lock
+       my @del_lock = ($group."\0".'locked_boardids');
+       $dellockoutcome = &Apache::lonnet::del('nohist_groupboards',\@del_lock,$cdom,$cnum);
+    } else {
+        $outcome = "error: could not obtain lockfile\n";
+        $dellockoutcome = 'ok';
+    }
+    if (!$newurl) {
+        return ($outcome,$newurl,$bbtitle,$dellockoutcome);
+    }
     $newurl=&unescape($newurl);
+    # need to check here if group_boards_$group.sequence is in the course
+    # if not - add it as an item in group_folder_$group.sequence 
     my $allbbsmap = &Apache::longroup::get_bbfolder_url($cdom,$cnum,$group);
     if ($allbbsmap =~ m|^/uploaded|) {
         my ($errtext,$fatal)=&Apache::lonratedt::mapread($allbbsmap);
@@ -208,7 +253,7 @@
         $outcome = 'error: discussion boards folder absent, '.
                    'or in unexpected location - '.$allbbsmap."\n";
     }
-    return ($outcome,$newurl,$bbtitle);
+    return ($outcome,$newurl,$bbtitle,$dellockoutcome);
 }
 
 sub display_error {