multpile foreign keys

callback_create.go

@@ -35,13 +35,15 @@ func Create(scope *Scope) {
 						}
 					}
 				} else if relationship := field.Relationship; relationship != nil && relationship.Kind == "belongs_to" {
-					if relationField := fields[relationship.ForeignDBName]; !scope.changeableField(relationField) {
+					for _, dbName := range relationship.ForeignDBNames {
+						if relationField := fields[dbName]; !scope.changeableField(relationField) {
 							columns = append(columns, scope.Quote(relationField.DBName))
 							sqls = append(sqls, scope.AddToVars(relationField.Field.Interface()))
 						}
 					}
 				}
 			}
+		}
 
 		returningKey := "*"
 		primaryField := scope.PrimaryField()

callback_shared.go

@@ -19,8 +19,13 @@ func SaveBeforeAssociations(scope *Scope) {
 			if relationship := field.Relationship; relationship != nil && relationship.Kind == "belongs_to" {
 				value := field.Field
 				scope.Err(scope.NewDB().Save(value.Addr().Interface()).Error)
-				if relationship.ForeignFieldName != "" {
+				if len(relationship.ForeignFieldNames) != 0 {
-					scope.Err(scope.SetColumn(relationship.ForeignFieldName, scope.New(value.Addr().Interface()).PrimaryKeyValue()))
+					for idx, fieldName := range relationship.ForeignFieldNames {
+						associationForeignName := relationship.AssociationForeignDBNames[idx]
+						if f, ok := scope.New(value.Addr().Interface()).FieldByName(associationForeignName); ok {
+							scope.Err(scope.SetColumn(fieldName, f.Field.Interface()))
+						}
+					}
 				}
 			}
 		}
@@ -44,8 +49,13 @@ func SaveAfterAssociations(scope *Scope) {
 						elem := value.Index(i).Addr().Interface()
 						newScope := newDB.NewScope(elem)
 
-						if relationship.JoinTableHandler == nil && relationship.ForeignFieldName != "" {
+						if relationship.JoinTableHandler == nil && len(relationship.ForeignFieldNames) != 0 {
-							scope.Err(newScope.SetColumn(relationship.ForeignFieldName, scope.PrimaryKeyValue()))
+							for idx, fieldName := range relationship.ForeignFieldNames {
+								associationForeignName := relationship.AssociationForeignDBNames[idx]
+								if f, ok := scope.New(value.Addr().Interface()).FieldByName(associationForeignName); ok {
+									scope.Err(scope.SetColumn(fieldName, f.Field.Interface()))
+								}
+							}
 						}
 
 						if relationship.PolymorphicType != "" {
@@ -61,8 +71,13 @@ func SaveAfterAssociations(scope *Scope) {
 				default:
 					elem := value.Addr().Interface()
 					newScope := scope.New(elem)
-					if relationship.ForeignFieldName != "" {
+					if len(relationship.ForeignFieldNames) != 0 {
-						scope.Err(newScope.SetColumn(relationship.ForeignFieldName, scope.PrimaryKeyValue()))
+						for idx, fieldName := range relationship.ForeignFieldNames {
+							associationForeignName := relationship.AssociationForeignDBNames[idx]
+							if f, ok := scope.New(value.Addr().Interface()).FieldByName(associationForeignName); ok {
+								scope.Err(scope.SetColumn(fieldName, f.Field.Interface()))
+							}
+						}
 					}
 
 					if relationship.PolymorphicType != "" {

callback_update.go

@@ -55,9 +55,10 @@ func Update(scope *Scope) {
 						sqls = append(sqls, fmt.Sprintf("%v = %v", scope.Quote(field.DBName), scope.AddToVars(field.Field.Interface())))
 					}
 				} else if relationship := field.Relationship; relationship != nil && relationship.Kind == "belongs_to" {
-					if relationField := fields[relationship.ForeignDBName]; !scope.changeableField(relationField) {
+					for _, dbName := range relationship.ForeignDBNames {
-						if !relationField.IsBlank {
+						if relationField := fields[dbName]; !scope.changeableField(relationField) && !relationField.IsBlank {
-							sqls = append(sqls, fmt.Sprintf("%v = %v", scope.Quote(relationField.DBName), scope.AddToVars(relationField.Field.Interface())))
+							sql := fmt.Sprintf("%v = %v", scope.Quote(relationField.DBName), scope.AddToVars(relationField.Field.Interface()))
+							sqls = append(sqls, sql)
 						}
 					}
 				}

join_table_handler.go

@@ -45,41 +45,18 @@ func (s *JoinTableHandler) Setup(relationship *Relationship, tableName string, s
 	s.TableName = tableName
 
 	s.Source = JoinTableSource{ModelType: source}
-	sourceScope := &Scope{Value: reflect.New(source).Interface()}
+	for idx, dbName := range relationship.ForeignFieldNames {
-	sourcePrimaryFields := sourceScope.GetModelStruct().PrimaryFields
-	for _, primaryField := range sourcePrimaryFields {
-		if relationship.ForeignDBName == "" {
-			relationship.ForeignFieldName = source.Name() + primaryField.Name
-			relationship.ForeignDBName = ToDBName(relationship.ForeignFieldName)
-		}
-
-		var dbName string
-		if len(sourcePrimaryFields) == 1 || primaryField.DBName == "id" {
-			dbName = relationship.ForeignDBName
-		} else {
-			dbName = ToDBName(source.Name() + primaryField.Name)
-		}
-
 		s.Source.ForeignKeys = append(s.Source.ForeignKeys, JoinTableForeignKey{
-			DBName:            dbName,
+			DBName:            relationship.ForeignDBNames[idx],
-			AssociationDBName: primaryField.DBName,
+			AssociationDBName: dbName,
 		})
 	}
 
 	s.Destination = JoinTableSource{ModelType: destination}
-	destinationScope := &Scope{Value: reflect.New(destination).Interface()}
+	for idx, dbName := range relationship.AssociationForeignFieldNames {
-	destinationPrimaryFields := destinationScope.GetModelStruct().PrimaryFields
-	for _, primaryField := range destinationPrimaryFields {
-		var dbName string
-		if len(sourcePrimaryFields) == 1 || primaryField.DBName == "id" {
-			dbName = relationship.AssociationForeignDBName
-		} else {
-			dbName = ToDBName(destinationScope.GetModelStruct().ModelType.Name() + primaryField.Name)
-		}
-
 		s.Destination.ForeignKeys = append(s.Destination.ForeignKeys, JoinTableForeignKey{
-			DBName:            dbName,
+			DBName:            relationship.AssociationForeignDBNames[idx],
-			AssociationDBName: primaryField.DBName,
+			AssociationDBName: dbName,
 		})
 	}
 }

main.go

@@ -445,7 +445,7 @@ func (s *DB) Association(column string) *Association {
 		err = errors.New("primary key can't be nil")
 	} else {
 		if field, ok := scope.FieldByName(column); ok {
-			if field.Relationship == nil || field.Relationship.ForeignFieldName == "" {
+			if field.Relationship == nil || len(field.Relationship.ForeignFieldNames) == 0 {
 				err = fmt.Errorf("invalid association %v for %v", column, scope.IndirectValue().Type())
 			} else {
 				return &Association{Scope: scope, Column: column, PrimaryKey: primaryField.Field.Interface(), Field: field}

model_struct.go

@@ -64,10 +64,10 @@ type Relationship struct {
 	Kind                         string
 	PolymorphicType              string
 	PolymorphicDBName            string
-	ForeignFieldName            string
+	ForeignFieldNames            []string
-	ForeignDBName               string
+	ForeignDBNames               []string
-	AssociationForeignFieldName string
+	AssociationForeignFieldNames []string
-	AssociationForeignDBName    string
+	AssociationForeignDBNames    []string
 	JoinTableHandler             JoinTableHandlerInterface
 }
 
@@ -190,12 +190,11 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 
 					var relationship = &Relationship{}
 
-					foreignKey := gormSettings["FOREIGNKEY"]
 					if polymorphic := gormSettings["POLYMORPHIC"]; polymorphic != "" {
 						if polymorphicField := getForeignField(polymorphic+"Id", toScope.GetStructFields()); polymorphicField != nil {
 							if polymorphicType := getForeignField(polymorphic+"Type", toScope.GetStructFields()); polymorphicType != nil {
-								relationship.ForeignFieldName = polymorphicField.Name
+								relationship.ForeignFieldNames = []string{polymorphicField.Name}
-								relationship.ForeignDBName = polymorphicField.DBName
+								relationship.ForeignDBNames = []string{polymorphicField.DBName}
 								relationship.PolymorphicType = polymorphicType.Name
 								relationship.PolymorphicDBName = polymorphicType.DBName
 								polymorphicType.IsForeignKey = true
@@ -204,6 +203,10 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 						}
 					}
 
+					var foreignKeys []string
+					if foreignKey, ok := gormSettings["FOREIGNKEY"]; ok {
+						foreignKeys := append(foreignKeys, gormSettings["FOREIGNKEY"])
+					}
 					switch indirectType.Kind() {
 					case reflect.Slice:
 						elemType := indirectType.Elem()
@@ -212,34 +215,63 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 						}
 
 						if elemType.Kind() == reflect.Struct {
-							if foreignKey == "" {
-								foreignKey = scopeType.Name() + "Id"
-							}
-
 							if many2many := gormSettings["MANY2MANY"]; many2many != "" {
 								relationship.Kind = "many_to_many"
-								associationForeignKey := gormSettings["ASSOCIATIONFOREIGNKEY"]
+
-								if associationForeignKey == "" {
+								// foreign keys
-									associationForeignKey = elemType.Name() + "Id"
+								if len(foreignKeys) == 0 {
+									for _, field := range scope.PrimaryFields() {
+										foreignKeys = append(foreignKeys, field.DBName)
+									}
 								}
 
-								relationship.ForeignFieldName = foreignKey
+								for _, foreignKey := range foreignKeys {
-								relationship.ForeignDBName = ToDBName(foreignKey)
+									if field, ok := scope.FieldByName(foreignKey); ok {
-								relationship.AssociationForeignFieldName = associationForeignKey
+										relationship.ForeignFieldNames = append(relationship.ForeignFieldNames, field.DBName)
-								relationship.AssociationForeignDBName = ToDBName(associationForeignKey)
+										joinTableDBName := ToDBName(scopeType.Name()) + "_" + field.DBName
+										relationship.ForeignDBNames = append(relationship.ForeignDBNames, joinTableDBName)
+									}
+								}
+
+								// association foreign keys
+								var associationForeignKeys []string
+								if foreignKey := gormSettings["ASSOCIATIONFOREIGNKEY"]; foreignKey != "" {
+									associationForeignKeys = []string{gormSettings["ASSOCIATIONFOREIGNKEY"]}
+								} else {
+									for _, field := range toScope.PrimaryFields() {
+										associationForeignKeys = append(associationForeignKeys, field.DBName)
+									}
+								}
+
+								for _, name := range associationForeignKeys {
+									if field, ok := toScope.FieldByName(name); ok {
+										relationship.AssociationForeignFieldNames = append(relationship.AssociationForeignFieldNames, name)
+										joinTableDBName := ToDBName(elemType.Name()) + "_" + field.DBName
+										relationship.AssociationForeignDBNames = append(relationship.AssociationForeignDBNames, joinTableDBName)
+									}
+								}
 
 								joinTableHandler := JoinTableHandler{}
 								joinTableHandler.Setup(relationship, many2many, scopeType, elemType)
 								relationship.JoinTableHandler = &joinTableHandler
 								field.Relationship = relationship
 							} else {
+								if len(foreignKeys) == 0 {
+									for _, field := range scope.PrimaryFields() {
+										foreignKeys = append(foreignKeys, scopeType.Name()+field.Name)
+									}
+								}
+
 								relationship.Kind = "has_many"
+								for _, foreignKey := range foreignKeys {
 									if foreignField := getForeignField(foreignKey, toScope.GetStructFields()); foreignField != nil {
-									relationship.ForeignFieldName = foreignField.Name
+										relationship.ForeignFieldNames = append(relationship.ForeignFieldNames, foreignField.Name)
-									relationship.ForeignDBName = foreignField.DBName
+										relationship.ForeignDBNames = append(relationship.ForeignDBNames, foreignField.DBName)
 										foreignField.IsForeignKey = true
-									field.Relationship = relationship
+									}
-								} else if relationship.ForeignFieldName != "" {
+								}
+
+								if len(relationship.ForeignFieldNames) != 0 {
 									field.Relationship = relationship
 								}
 							}
@@ -258,28 +290,42 @@ func (scope *Scope) GetModelStruct() *ModelStruct {
 							}
 							continue
 						} else {
-							belongsToForeignKey := foreignKey
+							belongsToForeignKeys := foreignKeys
-							if belongsToForeignKey == "" {
+							if len(belongsToForeignKeys) == 0 {
-								belongsToForeignKey = field.Name + "Id"
+								for _, field := range toScope.PrimaryFields() {
+									belongsToForeignKeys = append(belongsToForeignKeys, field.Name+field.Name)
+								}
 							}
 
-							if foreignField := getForeignField(belongsToForeignKey, fields); foreignField != nil {
+							for _, foreignKey := range belongsToForeignKeys {
-								relationship.Kind = "belongs_to"
+								if foreignField := getForeignField(foreignKey, fields); foreignField != nil {
-								relationship.ForeignFieldName = foreignField.Name
+									relationship.ForeignFieldNames = append(relationship.ForeignFieldNames, foreignField.Name)
-								relationship.ForeignDBName = foreignField.DBName
+									relationship.ForeignDBNames = append(relationship.ForeignDBNames, foreignField.DBName)
 									foreignField.IsForeignKey = true
+								}
+							}
+
+							if len(relationship.ForeignFieldNames) != 0 {
+								relationship.Kind = "belongs_to"
 								field.Relationship = relationship
 							} else {
-								if foreignKey == "" {
+								hasOneForeignKeys := foreignKeys
-									foreignKey = modelStruct.ModelType.Name() + "Id"
+								if len(hasOneForeignKeys) == 0 {
+									for _, field := range toScope.PrimaryFields() {
+										hasOneForeignKeys = append(hasOneForeignKeys, modelStruct.ModelType.Name()+field.Name)
 									}
-								relationship.Kind = "has_one"
+								}
+
+								for _, foreignKey := range hasOneForeignKeys {
 									if foreignField := getForeignField(foreignKey, toScope.GetStructFields()); foreignField != nil {
-									relationship.ForeignFieldName = foreignField.Name
+										relationship.ForeignFieldNames = append(relationship.ForeignFieldNames, foreignField.Name)
-									relationship.ForeignDBName = foreignField.DBName
+										relationship.ForeignDBNames = append(relationship.ForeignDBNames, foreignField.DBName)
 										foreignField.IsForeignKey = true
-									field.Relationship = relationship
+									}
-								} else if relationship.ForeignFieldName != "" {
+								}
+
+								if len(relationship.ForeignFieldNames) != 0 {
+									relationship.Kind = "has_one"
 									field.Relationship = relationship
 								}
 							}