Implement cascaded deletion of cached group members on DB level

The performance is obviously better to clean up stuff on DB level. As
Via is a foreign key, it can't be 0 any more.

etc/schema.Oracle

@@ -199,7 +199,8 @@ CREATE TABLE CachedGroupMembers (
         MemberId        NUMBER(11,0),
         Via             NUMBER(11,0),
         ImmediateParentId       NUMBER(11,0),
-        Disabled        NUMBER(11,0) DEFAULT 0 NOT NULL
+        Disabled        NUMBER(11,0) DEFAULT 0 NOT NULL,
+        FOREIGN KEY (Via) REFERENCES CachedGroupMembers(id) ON DELETE CASCADE
 );
 CREATE INDEX DisGrouMem ON CachedGroupMembers (GroupId, MemberId, Disabled);
 CREATE INDEX CachedGroupMembers2 ON CachedGroupMembers (MemberId, GroupId, Disabled);

etc/schema.Pg

@@ -325,6 +325,7 @@ CREATE TABLE CachedGroupMembers (
         Via int, 
         ImmediateParentId int, 
         Disabled integer NOT NULL DEFAULT 0 , 
+        FOREIGN KEY (Via) REFERENCES CachedGroupMembers(id) ON DELETE CASCADE,
         PRIMARY KEY (id)
 
 );

etc/schema.SQLite

@@ -221,11 +221,12 @@ create table CachedGroupMembers (
         MemberId int, 
         Via int, 
         ImmediateParentId int,
-        Disabled int2 NOT NULL DEFAULT 0  # if this cached group member is a member of this group by way of a disabled
+        Disabled int2 NOT NULL DEFAULT 0,  # if this cached group member is a member of this group by way of a disabled
                                            # group or this group is disabled, this will be set to 1
                                            # this allows us to not find members of disabled subgroups when listing off
                                            # group members recursively.
                                            # Also, this allows us to have the ACL system elide members of disabled groups
+        FOREIGN KEY (Via) REFERENCES CachedGroupMembers(id) ON DELETE CASCADE
 
 
 ) ;

etc/schema.mysql

@@ -207,6 +207,7 @@ create table CachedGroupMembers (
                                            # this allows us to not find members of disabled subgroups when listing off
                                            # group members recursively.
                                            # Also, this allows us to have the ACL system elide members of disabled groups
+        FOREIGN KEY (Via) REFERENCES CachedGroupMembers(id) ON DELETE CASCADE,
         PRIMARY KEY (id)
 ) ENGINE=InnoDB CHARACTER SET utf8mb4;
 

etc/upgrade/5.0.6/schema.Oracle

@@ -0,0 +1 @@
+ALTER TABLE CachedGroupMembers ADD FOREIGN KEY (Via) REFERENCES CachedGroupMembers(id) ON DELETE CASCADE;

etc/upgrade/5.0.6/schema.Pg

@@ -0,0 +1 @@
+ALTER TABLE CachedGroupMembers ADD FOREIGN KEY (Via) REFERENCES CachedGroupMembers(id) ON DELETE CASCADE;

etc/upgrade/5.0.6/schema.mysql

@@ -0,0 +1 @@
+ALTER TABLE CachedGroupMembers ADD FOREIGN KEY (Via) REFERENCES CachedGroupMembers(id) ON DELETE CASCADE;

lib/RT/CachedGroupMember.pm

@@ -99,7 +99,7 @@ sub Create {
     my %args = ( Group           => '',
                  Member          => '',
                  ImmediateParent => '',
-                 Via             => '0',
+                 Via             => undef,
                  Disabled        => '0',
                  @_ );
 
@@ -141,7 +141,12 @@ sub Create {
                            . $args{'Via'} );
         return (undef);  #this will percolate up and bail out of the transaction
     }
-    if ( $self->__Value('Via') == 0 ) {
+
+    # Check $args{Via} instead of __Value('Via') to avoid cache issues on
+    # SQLite that may reuse ids: t/validator/group_members.t fails with
+    # __Value('Via')
+
+    if ( !$args{Via} ) {
         my ( $vid, $vmsg ) = $self->__Set( Field => 'Via', Value => $id );
         unless ($vid) {
             $RT::Logger->warning( "Due to a via error, couldn't create "
@@ -181,44 +186,6 @@ sub Create {
 
 
 
-=head2 Delete
-
-Deletes the current CachedGroupMember from the group it's in and
-cascades the delete to all submembers.
-
-=cut
-
-sub Delete {
-    my $self = shift;
-
-
-    my $member = $self->MemberObj();
-    if ( $member->IsGroup ) {
-        my $deletable = RT::CachedGroupMembers->new( $self->CurrentUser );
-
-        $deletable->Limit( FIELD    => 'id',
-                           OPERATOR => '!=',
-                           VALUE    => $self->id );
-        $deletable->Limit( FIELD    => 'Via',
-                           OPERATOR => '=',
-                           VALUE    => $self->id );
-
-        while ( my $kid = $deletable->Next ) {
-            my ($ok, $msg) = $kid->Delete();
-            unless ($ok) {
-                $RT::Logger->error(
-                    "Couldn't delete CachedGroupMember " . $kid->Id );
-                return ($ok, $msg);
-            }
-        }
-    }
-    my ($ok, $msg) = $self->SUPER::Delete();
-    $RT::Logger->error( "Couldn't delete CachedGroupMember " . $self->Id ) unless $ok;
-    return ($ok, $msg);
-}
-
-
-
 =head2 SetDisabled
 
 SetDisableds the current CachedGroupMember from the group it's in and cascades 

lib/RT/GroupMember.pm

@@ -103,7 +103,7 @@ sub _InsertCGM {
         Member          => $self->MemberObj,
         Group           => $self->GroupObj,
         ImmediateParent => $self->GroupObj,
-        Via             => '0'
+        Via             => undef,
     );
 
 
@@ -289,7 +289,7 @@ sub _StashUser {
         Member          => $args{'Member'},
         Group           => $args{'Group'},
         ImmediateParent => $args{'Group'},
-        Via             => '0'
+        Via             => undef,
     );
 
     unless ($cached_id) {

lib/RT/Handle.pm

@@ -154,6 +154,7 @@ sub Connect {
     }
     elsif ( $db_type eq 'SQLite' ) {
         $self->dbh->{sqlite_see_if_its_a_number} = 1;
+        $self->dbh->do('PRAGMA foreign_keys = ON'); # ON DELETE CASCADE for CachedGroupMembers needs it
     }
 
     $self->dbh->{'LongReadLen'} = RT->Config->Get('MaxAttachmentSize');

lib/RT/Migrate/Importer.pm

@@ -632,7 +632,7 @@ sub CloseStream {
     # Groups
     $self->RunSQL(<<'EOF');
 INSERT INTO CachedGroupMembers (GroupId, MemberId, Via, ImmediateParentId, Disabled)
-    SELECT Groups.id, Groups.id, 0, Groups.id, Principals.Disabled FROM Groups
+    SELECT Groups.id, Groups.id, NULL, Groups.id, Principals.Disabled FROM Groups
     LEFT JOIN Principals ON ( Groups.id = Principals.id )
     LEFT JOIN CachedGroupMembers ON (
         Groups.id = CachedGroupMembers.GroupId
@@ -645,7 +645,7 @@ EOF
     # GroupMembers
     $self->RunSQL(<<'EOF');
 INSERT INTO CachedGroupMembers (GroupId, MemberId, Via, ImmediateParentId, Disabled)
-    SELECT GroupMembers.GroupId, GroupMembers.MemberId, 0, GroupMembers.GroupId, Principals.Disabled FROM GroupMembers
+    SELECT GroupMembers.GroupId, GroupMembers.MemberId, NULL, GroupMembers.GroupId, Principals.Disabled FROM GroupMembers
     LEFT JOIN Principals ON ( GroupMembers.GroupId = Principals.id )
     LEFT JOIN CachedGroupMembers ON (
         GroupMembers.GroupId = CachedGroupMembers.GroupId
@@ -657,7 +657,7 @@ EOF
 
     # Fixup Via
     $self->RunSQL(<<'EOF');
-UPDATE CachedGroupMembers SET Via=id WHERE Via=0
+UPDATE CachedGroupMembers SET Via=id WHERE Via IS NULL
 EOF
 
     # Cascaded GroupMembers, use the same SQL in rt-validator