Bug 285723: Cross-DB bz_add_column (Part of Bug 285111)

Patch By Max Kanat-Alexander <mkanat@kerio.com> r=Tomas.Kopal, a=justdave

3 files changed, 183 insertions, 15 deletions

diff --git a/Bugzilla/DB.pm b/Bugzilla/DB.pm
index c0a498e4c..07e23f0e7 100644
--- a/Bugzilla/DB.pm
+++ b/Bugzilla/DB.pm
@@ -323,6 +323,31 @@ sub bz_setup_database {
 # Schema Modification Methods
 #####################################################################
 
+sub bz_add_column {
+    my ($self, $table, $name, $new_def) = @_;
+
+    # You can't add a NOT NULL column to a table with
+    # no DEFAULT statement.
+    if ($new_def->{NOTNULL} && !exists $new_def->{DEFAULT}) {
+        die "Failed adding the column ${table}.${name}:\n  You cannot add"
+            . " a NOT NULL column with no default to an existing table.\n";
+    }
+
+    my $current_def = $self->bz_column_info($table, $name);
+
+    if (!$current_def) {
+        my @statements = $self->_bz_real_schema->get_add_column_ddl(
+            $table, $name, $new_def);
+        print "Adding new column $name to table $table ...\n";
+        foreach my $sql (@statements) {
+            $self->do($sql);
+        }
+        $self->_bz_real_schema->set_column($table, $name, $new_def);
+        $self->_bz_store_real_schema;
+    }
+}
+
+
 # XXX - Need to make this cross-db compatible
 # XXX - This shouldn't print stuff to stdout
 sub bz_add_field ($$$) {
@@ -617,8 +642,11 @@ sub _bz_init_schema_storage {
         print "Initializing the new Schema storage...\n";
         my $store_me = $self->_bz_schema->serialize_abstract();
         my $schema_version = $self->_bz_schema->SCHEMA_VERSION;
-        $self->do("INSERT INTO bz_schema (schema_data, version) VALUES (?,?)",
-                  undef, ($store_me, $schema_version));
+        my $sth = $self->prepare("INSERT INTO bz_schema "
+                                 ." (schema_data, version) VALUES (?,?)");
+        $sth->bind_param(1, $store_me, $self->BLOB_TYPE);
+        $sth->bind_param(2, Bugzilla::DB::Schema::SCHEMA_VERSION);
+        $sth->execute();
     } 
     # Sanity check
     elsif ($table_size > 1) {
@@ -650,7 +678,7 @@ sub _bz_real_schema {
     # XXX - Should I do the undef check here instead of in checksetup?
 
     $self->{private_real_schema} = 
-        _bz_schema->deserialize_abstract($data, $version);
+        $self->_bz_schema->deserialize_abstract($data, $version);
 
     return $self->{private_real_schema};
 }
@@ -680,9 +708,12 @@ sub _bz_store_real_schema {
     # that we read from the database. So we use the actual hash
     # member instead of the subroutine call. If the hash
     # member is not defined, we will (and should) fail.
-    my $store_me = $self->{_bz_real_schema}->serialize_abstract();
-    $self->do("UPDATE bz_schema SET schema_data = ?, version = ?",
-              undef, $store_me, Bugzilla::DB::Schema::SCHEMA_VERSION);
+    my $store_me = $self->{private_real_schema}->serialize_abstract();
+    my $sth = $self->prepare("UPDATE bz_schema 
+                                 SET schema_data = ?, version = ?");
+    $sth->bind_param(1, $store_me, $self->BLOB_TYPE);
+    $sth->bind_param(2, Bugzilla::DB::Schema::SCHEMA_VERSION);
+    $sth->execute();
 }
 
 1;
@@ -714,7 +745,10 @@ Bugzilla::DB - Database access routines, using L<DBI>
   # Get the results
   my @result = $sth->fetchrow_array;
 
-  # Schema Changes
+  # Schema Modification
+  $dbh->bz_add_column($table, $name, \%definition);
+
+  # Schema Modification (DEPRECATED)
   $dbh->bz_add_field($table, $column, $definition);
   $dbh->bz_change_field_type($table, $column, $newtype);
   $dbh->bz_drop_field($table, $column);
@@ -1004,9 +1038,36 @@ These methods return information about data in the database.
               $column = name of column containing serial data type (scalar)
  Returns:     Last inserted ID (scalar)
 
+
 =head2 Schema Modification Methods
 
-These methods modify the current Bugzilla schema.
+These methods modify the current Bugzilla Schema.
+
+Where a parameter says "Abstract index/column definition", it returns/takes
+information in the formats defined for indexes and columns in
+C<Bugzilla::DB::Schema::ABSTRACT_SCHEMA>.
+
+=over 4
+
+=item C<bz_add_column($table, $name, \%definition)>
+
+ Description: Adds a new column to a table in the database. Prints out
+              a brief statement that it did so, to stdout.
+              Note that you cannot add a NOT NULL column that has no
+              default -- the database won't know what to set all
+              the NOT NULL values to.
+ Params:      $table = the table where the column is being added
+              $name  = the name of the new column
+              \%definition = Abstract column definition for the new column
+ Returns:     nothing
+
+=back
+
+
+=head2 Deprecated Schema Modification Methods
+
+These methods modify the current Bugzilla schema, for MySQL only. 
+Do not use them in new code.
 
 =over 4
 
diff --git a/Bugzilla/DB/Schema.pm b/Bugzilla/DB/Schema.pm
index d246ad542..d4a59ed78 100644
--- a/Bugzilla/DB/Schema.pm
+++ b/Bugzilla/DB/Schema.pm
@@ -32,6 +32,8 @@ package Bugzilla::DB::Schema;
 
 use strict;
 use Bugzilla::Error;
+use Bugzilla::Util;
+
 use Storable qw(dclone freeze thaw);
 
 =head1 NAME
@@ -1155,7 +1157,14 @@ sub get_type_ddl {
 
     my $type = $finfo->{TYPE};
     die "A valid TYPE was not specified for this column." unless ($type);
+
     my $default = $finfo->{DEFAULT};
+    # Replace any abstract default value (such as 'TRUE' or 'FALSE')
+    # with its database-specific implementation.
+    if ( defined $default && exists($self->{db_specific}->{$default}) ) {
+        $default = $self->{db_specific}->{$default};
+    }
+
     my $fkref = $self->{enable_references} ? $finfo->{REFERENCES} : undef;
     my $type_ddl = $self->{db_specific}{$type} || $type;
     $type_ddl .= " NOT NULL" if ($finfo->{NOTNULL});
@@ -1348,6 +1357,26 @@ sub _get_create_index_ddl {
 
 } #eosub--_get_create_index_ddl
 #--------------------------------------------------------------------------
+
+sub get_add_column_ddl {
+=item C<get_alter_ddl($table, $column, \%definition)>
+
+ Description: Generate SQL to add a column to a table.
+ Params:      $table - The table containing the column.
+              $column - The name of the column being added.
+              \%definition - The new definition for the column,
+                  in standard C<ABSTRACT_SCHEMA> format.
+ Returns:     An array of SQL statements.
+
+=cut
+    my ($self, $table, $column, $definition) = @_;
+
+    my $statement = "ALTER TABLE $table ADD COLUMN $column " .
+        $self->get_type_ddl($definition);
+
+    return ($statement);
+}
+
 sub get_column_abstract {
 
 =item C<get_column_abstract($table, $column)>
@@ -1367,7 +1396,8 @@ sub get_column_abstract {
     # Prevent a possible dereferencing of an undef hash, if the
     # table doesn't exist.
     if (exists $self->{abstract_schema}->{$table}) {
-        return $self->{abstract_schema}->{$table}{FIELDS}{$column};
+        my %fields = (@{ $self->{abstract_schema}{$table}{FIELDS} });
+        return $fields{$column};
     }
     return undef;
 }
@@ -1390,11 +1420,52 @@ sub get_index_abstract {
     # Prevent a possible dereferencing of an undef hash, if the
     # table doesn't exist.
     if (exists $self->{abstract_schema}->{$table}) {
-        return $self->{abstract_schema}->{$table}{INDEXES}{$index};
+        my %indexes = (@{ $self->{abstract_schema}{$table}{INDEXES} });
+        return $indexes{$index};
     }
     return undef;
 }
 
+sub set_column {
+
+=item C<set_column($table, $column, \%new_def)>
+
+ Description: Changes the definition of a column in this Schema object.
+              If the column doesn't exist, it will be added.
+              The table that you specify must already exist in the Schema.
+              NOTE: This does not affect the database on the disk.
+              Use the C<Bugzilla::DB> "Schema Modification Methods"
+              if you want to do that.
+ Params:      $table - The name of the table that the column is on.
+              $column - The name of the column.
+              \%new_def - The new definition for the column, in 
+                  C<ABSTRACT_SCHEMA> format.
+ Returns:     nothing
+
+=cut
+
+    my ($self, $table, $column, $new_def) = @_;
+
+    my $fields = \@{ $self->{schema}{$table}{FIELDS} };
+    my $abstract_fields = \@{ $self->{abstract_schema}{$table}{FIELDS} };
+
+    my $field_position = lsearch($fields, $column) + 1;
+    # If the column doesn't exist, then add it.
+    if (!$field_position) {
+        push(@$fields, $column);
+        push(@$fields, $new_def);
+        push(@$abstract_fields, $column);
+        push(@$abstract_fields, $new_def);
+    }
+    # We're modifying an existing column.
+    else {
+        splice(@$fields, $field_position, 1, $new_def);
+        splice(@$abstract_fields, $field_position, 1, $new_def);
+    }
+
+    $self->_adjust_schema();
+}
+
 
 =head1 SERIALIZATION/DESERIALIZATION
 
@@ -1439,14 +1510,14 @@ sub serialize_abstract {
 sub deserialize_abstract {
     my ($class, $serialized, $version) = @_;
 
-    my %thawed_hash = thaw($serialized);
+    my $thawed_hash = thaw($serialized);
 
     # At this point, we have no backwards-compatibility
     # code to write, so $version is ignored.
     # For what $version ought to be used for, see the
     # "private" section of the SCHEMA_VERSION docs.
 
-    return $class->new(undef, \%thawed_hash);
+    return $class->new(undef, $thawed_hash);
 }
 
 1;
diff --git a/Bugzilla/DB/Schema/Pg.pm b/Bugzilla/DB/Schema/Pg.pm
index 795ad53ff..3a45744bb 100644
--- a/Bugzilla/DB/Schema/Pg.pm
+++ b/Bugzilla/DB/Schema/Pg.pm
@@ -44,12 +44,14 @@ sub _initialize {
         if ($self->{schema}{$table}{INDEXES}) {
             foreach my $index (@{ $self->{schema}{$table}{INDEXES} }) {
                 if (ref($index) eq 'HASH') {
-                    delete($index->{TYPE}) if ($index->{TYPE} eq 'FULLTEXT');
+                    delete($index->{TYPE}) if (exists $index->{TYPE} 
+                        && $index->{TYPE} eq 'FULLTEXT');
                 }
             }
             foreach my $index (@{ $self->{abstract_schema}{$table}{INDEXES} }) {
                 if (ref($index) eq 'HASH') {
-                    delete($index->{TYPE}) if ($index->{TYPE} eq 'FULLTEXT');
+                    delete($index->{TYPE}) if (exists $index->{TYPE} 
+                        && $index->{TYPE} eq 'FULLTEXT');
                 }
             }
         }
@@ -85,5 +87,39 @@ sub _initialize {
     return $self;
 
 } #eosub--_initialize
-#------------------------------------------------------------------------------
+#--------------------------------------------------------------------
+
+# Overridden because Pg has such weird ALTER TABLE problems.
+sub get_add_column_ddl {
+    my ($self, $table, $column, $definition) = @_;
+
+    my @statements;
+    my $specific = $self->{db_specific};
+
+    my $type = $definition->{TYPE};
+    $type = $specific->{$type} if exists $specific->{$type};
+    push(@statements, "ALTER TABLE $table ADD COLUMN $column $type");
+
+    my $default = $definition->{DEFAULT};
+    # Replace any abstract default value (such as 'TRUE' or 'FALSE')
+    # with its database-specific implementation.
+    if (defined $default) {
+        $default = $specific->{$default} if exists $specific->{$default};
+        push(@statements, "ALTER TABLE $table ALTER COLUMN $column "
+                         . " SET DEFAULT $default");
+    }
+
+    if ($definition->{NOTNULL}) {
+        push(@statements, "ALTER TABLE $table ALTER COLUMN $column "
+                         . " SET NOT NULL");
+    }
+
+    if ($definition->{PRIMARYKEY}) {
+         push(@statements, "ALTER TABLE $table ALTER COLUMN $column "
+                         . " SET ADD PRIMARY KEY");
+    }
+
+    return @statements;
+}
+
 1;