Added more possibilities for transaction hooks

main.go

@@ -29,7 +29,9 @@ type DB struct {
 	dialect       Dialect
 	singularTable bool
 
-	afterCommitCallbacks []func(db *DB)
+	afterCommitCallbacks      []func(db *DB)
+	afterRollbackCallbacks    []func(db *DB)
+	afterTransactionCallbacks []func(db *DB)
 }
 
 // Open initialize a new db connection, need to import driver first, e.g:
@@ -538,9 +540,11 @@ func (s *DB) Rollback() *DB {
 	return s
 }
 
-// AfterCommit invoke callback after transaction committed
+// AppendAfterCommitCallback invoke callback after transaction committed
 // If no transaction is currently running, it will be invoked immediately
-func (s *DB) AfterCommit(f func(db *DB)) {
+// This method appends the given callback function to the register callback functions.
+// This means, that the callback will be invoked after all previously registered callbacks.
+func (s *DB) AppendAfterCommitCallback(f func(db *DB)) {
 	if db, ok := s.db.(sqlTx); ok && db != nil {
 		s.afterCommitCallbacks = append(s.afterCommitCallbacks, f)
 	} else {
@@ -548,6 +552,62 @@ func (s *DB) AfterCommit(f func(db *DB)) {
 	}
 }
 
+// PrependAfterCommitCallback invoke callback after transaction committed
+// If no transaction is currently running, it will be invoked immediately
+// This method prepends the given callback function to the register callback functions.
+// This means, that the callback will be invoked before all previously registered callbacks.
+func (s *DB) PrependAfterCommitCallback(f func(db *DB)) {
+	if db, ok := s.db.(sqlTx); ok && db != nil {
+		s.afterCommitCallbacks = append([]func(db *DB){f}, s.afterCommitCallbacks...)
+	} else {
+		f(s)
+	}
+}
+
+// AppendAfterRollbackCallback invoke callback after transaction rolled back
+// If no transaction is currently running, it won't be called
+// This method appends the given callback function to the register callback functions.
+// This means, that the callback will be invoked after all previously registered callbacks.
+func (s *DB) AppendAfterRollbackCallback(f func(db *DB)) {
+	if db, ok := s.db.(sqlTx); ok && db != nil {
+		s.afterRollbackCallbacks = append(s.afterRollbackCallbacks, f)
+	}
+}
+
+// PrependAfterRollbackCallback invoke callback after transaction rolled back.
+// If no transaction is currently running, it won't be called
+// This method prepends the given callback function to the register callback functions.
+// This means, that the callback will be invoked before all previously registered callbacks.
+func (s *DB) PrependAfterRollbackCallback(f func(db *DB)) {
+	if db, ok := s.db.(sqlTx); ok && db != nil {
+		s.afterRollbackCallbacks = append([]func(db *DB){f}, s.afterRollbackCallbacks...)
+	}
+}
+
+// AppendAfterTransactionCallback invoke callback after transaction finished (committed or rolled back).
+// If no transaction is currently running, it will be invoked immediately
+// This method appends the given callback function to the register callback functions.
+// This means, that the callback will be invoked after all previously registered callbacks.
+func (s *DB) AppendAfterTransactionCallback(f func(db *DB)) {
+	if db, ok := s.db.(sqlTx); ok && db != nil {
+		s.afterTransactionCallbacks = append(s.afterTransactionCallbacks, f)
+	} else {
+		f(s)
+	}
+}
+
+// PrependAfterTransactionCallback invoke callback after transaction finished (committed or rolled back).
+// If no transaction is currently running, it will be invoked immediately
+// This method prepends the given callback function to the register callback functions.
+// This means, that the callback will be invoked before all previously registered callbacks.
+func (s *DB) PrependAfterTransactionCallback(f func(db *DB)) {
+	if db, ok := s.db.(sqlTx); ok && db != nil {
+		s.afterTransactionCallbacks = append([]func(db *DB){f}, s.afterTransactionCallbacks...)
+	} else {
+		f(s)
+	}
+}
+
 // WrapInTx wraps a method in a transaction
 func (s *DB) WrapInTx(f func(tx *DB) error) (err error) {
 	if _, ok := s.db.(*sql.Tx); ok {
@@ -570,14 +630,26 @@ func (s *DB) WrapInTx(f func(tx *DB) error) (err error) {
 						err = fmt.Errorf("Transacton code and rollback failed: %s; %s", err, rollbackErr)
 					}
 				}
+
+				for _, callback := range tx.afterRollbackCallbacks {
+					callback(s)
+				}
+
+				for _, callback := range tx.afterTransactionCallbacks {
+					callback(s)
+				}
 			}
 		}()
 		err = f(tx)
 		if err == nil {
 			err = tx.Commit().Error
 			if err == nil {
-				for i := len(tx.afterCommitCallbacks) - 1; i >= 0; i-- {
+				for _, callback := range tx.afterCommitCallbacks {
-					tx.afterCommitCallbacks[i](s)
+					callback(s)
+				}
+
+				for _, callback := range tx.afterTransactionCallbacks {
+					callback(s)
 				}
 			}
 		}