Allow using Session instead of Engine (#56)

xormigrate.go

@@ -11,25 +11,35 @@ const (
 	initSchemaMigrationId = "SCHEMA_INIT"
 )
 
-// MigrateFunc is the func signature for migratinx.
+// MigrateFunc is the func signature for migrating.
 type MigrateFunc func(*xorm.Engine) error
 
-// RollbackFunc is the func signature for rollbackinx.
+// RollbackFunc is the func signature for rollbacking.
 type RollbackFunc func(*xorm.Engine) error
 
 // InitSchemaFunc is the func signature for initializing the schema.
 type InitSchemaFunc func(*xorm.Engine) error
 
+// MigrateFunc is the func signature for migrating.
+type MigrateFuncSession func(*xorm.Session) error
+
+// RollbackFunc is the func signature for rollbacking.
+type RollbackFuncSession func(*xorm.Session) error
+
 // Migration represents a database migration (a modification to be made on the database).
 type Migration struct {
 	// ID is the migration identifier. Usually a timestamp like "201601021504".
 	ID string `xorm:"id"`
 	// Description is the migration description, which is optionally printed out when the migration is ran.
 	Description string
-	// Migrate is a function that will br executed while running this migration.
+	// Migrate is a function that will be executed while running this migration.
 	Migrate MigrateFunc `xorm:"-"`
 	// Rollback will be executed on rollback. Can be nil.
 	Rollback RollbackFunc `xorm:"-"`
+	// MigrateSession is a function that will be executed while running this migration, using xorm.Session.
+	MigrateSession MigrateFuncSession `xorm:"-"`
+	// RollbackSession will be executed on rollback, using xorm.Session. Can be nil.
+	RollbackSession RollbackFuncSession `xorm:"-"`
 	// Long marks the migration an non-required migration that will likely take a long time. Must use Xormigrate.AllowLong() to be enabled.
 	Long bool `xorm:"-"`
 }
@@ -251,14 +261,25 @@ func (x *Xormigrate) RollbackMigration(m *Migration) error {
 }
 
 func (x *Xormigrate) rollbackMigration(m *Migration) error {
-	if m.Rollback == nil {
+	if m.Rollback == nil && m.RollbackSession == nil {
 		return ErrRollbackImpossible
 	}
 	if len(m.Description) > 0 {
 		logger.Errorf("Rolling back migration: %s", m.Description)
 	}
-	if err := m.Rollback(x.db); err != nil {
-		return err
+	if m.Rollback != nil {
+		if err := m.Rollback(x.db); err != nil {
+			return err
+		}
+	} else {
+		sess := x.db.NewSession()
+		if err := m.RollbackSession(sess); err != nil {
+			rollbackSession(sess)
+			return err
+		}
+		if err := sess.Commit(); err != nil {
+			return err
+		}
 	}
 	if _, err := x.db.In("id", m.ID).Delete(&Migration{}); err != nil {
 		return err
@@ -268,7 +289,12 @@ func (x *Xormigrate) rollbackMigration(m *Migration) error {
 
 func (x *Xormigrate) runInitSchema() error {
 	logger.Info("Initializing Schema")
+	sess := x.db.NewSession()
 	if err := x.initSchema(x.db); err != nil {
+		rollbackSession(sess)
+		return err
+	}
+	if err := sess.Commit(); err != nil {
 		return err
 	}
 	if err := x.insertMigration(initSchemaMigrationId); err != nil {
@@ -293,8 +319,19 @@ func (x *Xormigrate) runMigration(migration *Migration) error {
 		if len(migration.Description) > 0 {
 			logger.Info(migration.Description)
 		}
-		if err := migration.Migrate(x.db); err != nil {
-			return fmt.Errorf("migration %s failed: %s", migration.ID, err.Error())
+		if migration.Migrate != nil {
+			if err := migration.Migrate(x.db); err != nil {
+				return fmt.Errorf("migration %s failed: %s", migration.ID, err.Error())
+			}
+		} else {
+			sess := x.db.NewSession()
+			if err := migration.MigrateSession(sess); err != nil {
+				rollbackSession(sess)
+				return fmt.Errorf("migration %s failed: %s", migration.ID, err.Error())
+			}
+			if err := sess.Commit(); err != nil {
+				return err
+			}
 		}
 
 		if err := x.insertMigration(migration.ID); err != nil {
@@ -339,3 +376,9 @@ func (x *Xormigrate) insertMigration(id string) error {
 	_, err := x.db.Insert(&Migration{ID: id})
 	return err
 }
+
+func rollbackSession(sess *xorm.Session) {
+	if err := sess.Rollback(); err != nil {
+		logger.Errorf("Failed to rollback session: %v", err)
+	}
+}

xormigrate_test.go

@@ -38,6 +38,28 @@ var migrations = []*Migration{
 	},
 }
 
+var migrationsSession = []*Migration{
+	{
+		ID:          "201608301400",
+		Description: "Add Person",
+		MigrateSession: func(tx *xorm.Session) error {
+			return tx.Sync(&Person{})
+		},
+		RollbackSession: func(tx *xorm.Session) error {
+			return tx.DropTable(&Person{})
+		},
+	},
+	{
+		ID: "201608301430",
+		MigrateSession: func(tx *xorm.Session) error {
+			return tx.Sync2(&Pet{})
+		},
+		RollbackSession: func(tx *xorm.Session) error {
+			return tx.DropTable(&Pet{})
+		},
+	},
+}
+
 var extendedMigrations = append(migrations, &Migration{
 	ID: "201807221927",
 	Migrate: func(tx *xorm.Engine) error {
@@ -355,6 +377,42 @@ func TestAllowLong(t *testing.T) {
 	})
 }
 
+func TestMigrationSession(t *testing.T) {
+	forEachDatabase(t, func(db *xorm.Engine) {
+		m := New(db, migrationsSession)
+
+		err := m.Migrate()
+		assert.NoError(t, err)
+		has, err := db.IsTableExist(&Person{})
+		assert.NoError(t, err)
+		assert.True(t, has)
+		has, err = db.IsTableExist(&Pet{})
+		assert.NoError(t, err)
+		assert.True(t, has)
+		assert.Equal(t, int64(2), tableCount(t, db))
+
+		err = m.RollbackLast()
+		assert.NoError(t, err)
+		has, err = db.IsTableExist(&Person{})
+		assert.NoError(t, err)
+		assert.True(t, has)
+		has, err = db.Exist(&Pet{})
+		assert.Error(t, err)
+		assert.False(t, has)
+		assert.Equal(t, int64(1), tableCount(t, db))
+
+		err = m.RollbackLast()
+		assert.NoError(t, err)
+		has, err = db.IsTableExist(&Person{})
+		assert.NoError(t, err)
+		assert.False(t, has)
+		has, err = db.IsTableExist(&Pet{})
+		assert.NoError(t, err)
+		assert.False(t, has)
+		assert.Equal(t, int64(0), tableCount(t, db))
+	})
+}
+
 func tableCount(t *testing.T, db *xorm.Engine) (count int64) {
 	count, err := db.Count(&Migration{})
 	assert.NoError(t, err)