Add JoinTableHandler

association.go

@@ -71,15 +71,15 @@ func (association *Association) Delete(values ...interface{}) *Association {
 	if len(primaryKeys) == 0 {
 		association.setErr(errors.New("no primary key found"))
 	} else {
+		scope := association.Scope
 		relationship := association.Field.Relationship
 		// many to many
 		if relationship.Kind == "many_to_many" {
-			whereSql := fmt.Sprintf("%v.%v = ? AND %v.%v IN (?)",
+			sql := fmt.Sprintf("%v.%v = ? AND %v.%v IN (?)",
-				relationship.JoinTable, association.Scope.Quote(relationship.ForeignDBName),
+				scope.Quote(relationship.JoinTable), scope.Quote(relationship.ForeignDBName),
-				relationship.JoinTable, association.Scope.Quote(relationship.AssociationForeignDBName))
+				scope.Quote(relationship.JoinTable), scope.Quote(relationship.AssociationForeignDBName))
-
+			query := scope.NewDB().Table(relationship.JoinTable).Where(sql, association.PrimaryKey, primaryKeys)
-			if err := association.Scope.DB().Table(relationship.JoinTable).
+			if err := scope.db.GetJoinTableHandler(relationship.JoinTable).Delete(query, relationship); err == nil {
-				Where(whereSql, association.PrimaryKey, primaryKeys).Delete("").Error; err == nil {
 				leftValues := reflect.Zero(association.Field.Field.Type())
 				for i := 0; i < association.Field.Field.Len(); i++ {
 					value := association.Field.Field.Index(i)
@@ -132,11 +132,9 @@ func (association *Association) Replace(values ...interface{}) *Association {
 			addedPrimaryKeys = append(addedPrimaryKeys, primaryKey)
 		}
 
-		whereSql := fmt.Sprintf("%v.%v = ? AND %v.%v NOT IN (?)",
+		sql := fmt.Sprintf("%v.%v = ? AND %v.%v NOT IN (?)", scope.Quote(relationship.JoinTable), scope.Quote(relationship.ForeignDBName), scope.Quote(relationship.JoinTable), scope.Quote(relationship.AssociationForeignDBName))
-			relationship.JoinTable, association.Scope.Quote(relationship.ForeignDBName),
+		query := scope.NewDB().Table(relationship.JoinTable).Where(sql, association.PrimaryKey, addedPrimaryKeys)
-			relationship.JoinTable, association.Scope.Quote(relationship.AssociationForeignDBName))
+		association.setErr(scope.db.GetJoinTableHandler(relationship.JoinTable).Delete(query, relationship))
-
-		scope.DB().Table(relationship.JoinTable).Where(whereSql, association.PrimaryKey, addedPrimaryKeys).Delete("")
 	} else {
 		association.setErr(errors.New("replace only support many to many"))
 	}
@@ -147,8 +145,9 @@ func (association *Association) Clear() *Association {
 	relationship := association.Field.Relationship
 	scope := association.Scope
 	if relationship.Kind == "many_to_many" {
-		whereSql := fmt.Sprintf("%v.%v = ?", relationship.JoinTable, scope.Quote(relationship.ForeignDBName))
+		sql := fmt.Sprintf("%v.%v = ?", relationship.JoinTable, scope.Quote(relationship.ForeignDBName))
-		if err := scope.DB().Table(relationship.JoinTable).Where(whereSql, association.PrimaryKey).Delete("").Error; err == nil {
+		query := scope.NewDB().Table(relationship.JoinTable).Where(sql, association.PrimaryKey)
+		if err := scope.db.GetJoinTableHandler(relationship.JoinTable).Delete(query, relationship); err == nil {
 			association.Field.Set(reflect.Zero(association.Field.Field.Type()))
 		} else {
 			association.setErr(err)
@@ -166,9 +165,10 @@ func (association *Association) Count() int {
 	newScope := scope.New(association.Field.Field.Interface())
 
 	if relationship.Kind == "many_to_many" {
-		scope.DB().Table(relationship.JoinTable).
+		query := scope.DB().Table(relationship.JoinTable).
 			Select("COUNT(DISTINCT ?)", relationship.AssociationForeignDBName).
-			Where(relationship.ForeignDBName+" = ?", association.PrimaryKey).Row().Scan(&count)
+			Where(relationship.ForeignDBName+" = ?", association.PrimaryKey)
+		scope.db.GetJoinTableHandler(relationship.JoinTable).Scope(query, relationship).Row().Scan(&count)
 	} else if relationship.Kind == "has_many" || relationship.Kind == "has_one" {
 		whereSql := fmt.Sprintf("%v.%v = ?", newScope.QuotedTableName(), newScope.Quote(relationship.ForeignDBName))
 		countScope := scope.DB().Table(newScope.TableName()).Where(whereSql, association.PrimaryKey)

callback_shared.go

@@ -1,10 +1,6 @@
 package gorm
 
-import (
+import "reflect"
-	"fmt"
-	"reflect"
-	"strings"
-)
 
 func BeginTransaction(scope *Scope) {
 	scope.Begin()
@@ -53,24 +49,8 @@ func SaveAfterAssociations(scope *Scope) {
 						scope.Err(newDB.Save(elem).Error)
 
 						if joinTable := relationship.JoinTable; joinTable != "" {
-							quotedForeignDBName := scope.Quote(relationship.ForeignDBName)
+							scope.Err(scope.db.GetJoinTableHandler(joinTable).
-							foreignValue := scope.PrimaryKeyValue()
+								Add(scope.NewDB(), relationship, scope.PrimaryKeyValue(), newScope.PrimaryKeyValue()))
-							quoteAssociationForeignDBName := scope.Quote(relationship.AssociationForeignDBName)
-							associationForeignValue := newScope.PrimaryKeyValue()
-
-							newScope.Raw(fmt.Sprintf(
-								"INSERT INTO %v (%v) SELECT %v %v WHERE NOT EXISTS (SELECT * FROM %v WHERE %v = %v AND %v = %v);",
-								joinTable,
-								strings.Join([]string{quotedForeignDBName, quoteAssociationForeignDBName}, ","),
-								strings.Join([]string{newScope.AddToVars(foreignValue), newScope.AddToVars(associationForeignValue)}, ","),
-								scope.Dialect().SelectFromDummyTable(),
-								joinTable,
-								quotedForeignDBName,
-								newScope.AddToVars(foreignValue),
-								quoteAssociationForeignDBName,
-								newScope.AddToVars(associationForeignValue),
-							))
-							scope.Err(scope.NewDB().Exec(newScope.Sql, newScope.SqlVars...).Error)
 						}
 					}
 				default:

join_table.go

@@ -0,0 +1,42 @@
+package gorm
+
+import (
+	"fmt"
+	"strings"
+)
+
+type JoinTableHandler interface {
+	Add(*DB, *Relationship, interface{}, interface{}) error
+	Delete(*DB, *Relationship) error
+	Scope(*DB, *Relationship) *DB
+}
+
+type defaultJoinTableHandler struct{}
+
+func (*defaultJoinTableHandler) Add(db *DB, relationship *Relationship, foreignValue interface{}, associationValue interface{}) error {
+	scope := db.NewScope("")
+	quotedForeignDBName := scope.Quote(relationship.ForeignDBName)
+	quotedAssociationDBName := scope.Quote(relationship.AssociationForeignDBName)
+
+	sql := fmt.Sprintf(
+		"INSERT INTO %v (%v) SELECT ?,? %v WHERE NOT EXISTS (SELECT * FROM %v WHERE %v = ? AND %v = ?);",
+		scope.Quote(relationship.JoinTable),
+		strings.Join([]string{quotedForeignDBName, quotedAssociationDBName}, ","),
+		scope.Dialect().SelectFromDummyTable(),
+		scope.Quote(relationship.JoinTable),
+		quotedForeignDBName,
+		quotedAssociationDBName,
+	)
+
+	return db.Exec(sql, foreignValue, associationValue, foreignValue, associationValue).Error
+}
+
+func (*defaultJoinTableHandler) Delete(db *DB, relationship *Relationship) error {
+	return db.Delete("").Error
+}
+
+func (*defaultJoinTableHandler) Scope(db *DB, relationship *Relationship) *DB {
+	return db
+}
+
+var DefaultJoinTableHandler = &defaultJoinTableHandler{}

main.go

@@ -34,6 +34,7 @@ type DB struct {
 	singularTable     bool
 	source            string
 	values            map[string]interface{}
+	joinTableHandlers map[string]JoinTableHandler
 }
 
 func Open(dialect string, args ...interface{}) (DB, error) {
@@ -91,20 +92,6 @@ func (db *DB) NewScope(value interface{}) *Scope {
 	return &Scope{db: dbClone, Search: dbClone.search, Value: value}
 }
 
-func (s *DB) FreshDB() *DB {
-	newDB := &DB{
-		dialect:      s.dialect,
-		logger:       s.logger,
-		callback:     s.parent.callback.clone(),
-		source:       s.source,
-		values:       map[string]interface{}{},
-		db:           s.db,
-		ModelStructs: map[reflect.Type]*ModelStruct{},
-	}
-	newDB.parent = newDB
-	return newDB
-}
-
 // CommonDB Return the underlying sql.DB or sql.Tx instance.
 // Use of this method is discouraged. It's mainly intended to allow
 // coexistence with legacy non-GORM code.
@@ -473,3 +460,29 @@ func (s *DB) Get(name string) (value interface{}, ok bool) {
 	value, ok = s.values[name]
 	return
 }
+
+func (s *DB) GetJoinTableHandler(table string) JoinTableHandler {
+	if s.parent.joinTableHandlers != nil {
+		if joinTableHandler, ok := s.parent.joinTableHandlers[table]; ok {
+			return joinTableHandler
+		}
+		if joinTableHandler, ok := s.parent.joinTableHandlers["*"]; ok {
+			return joinTableHandler
+		}
+	}
+	return DefaultJoinTableHandler
+}
+
+func (s *DB) SetJoinTableHandler(joinTableHandler JoinTableHandler, tables ...string) {
+	if s.parent.joinTableHandlers == nil {
+		s.parent.joinTableHandlers = map[string]JoinTableHandler{}
+	}
+
+	if len(tables) > 0 {
+		for _, table := range tables {
+			s.parent.joinTableHandlers[table] = joinTableHandler
+		}
+	} else {
+		s.parent.joinTableHandlers["*"] = joinTableHandler
+	}
+}