ent/entc/gen/template/dialect/sql/errors.tmpl

{{/* custom errors and errors handlers from sql dialects */}}
{{ define "dialect/sql/errors" }}
func isSQLConstraintError(err error) (*ErrConstraintFailed, bool) {
	// Error number 1062 is ER_DUP_ENTRY in mysql, and "UNIQUE constraint failed" is SQLite prefix.
	if msg := err.Error(); strings.HasPrefix(msg, "Error 1062") || strings.HasPrefix(msg, "UNIQUE constraint failed") {
		return &ErrConstraintFailed{msg, err}, true
	}
	return nil, false
}

// rollback calls to tx.Rollback and wraps the given error with the rollback error if occurred.
func rollback(tx dialect.Tx, err error) error {
	if rerr := tx.Rollback(); rerr != nil {
		err = fmt.Errorf("%s: %v", err.Error(), rerr)
	}
	if err, ok := isSQLConstraintError(err); ok {
		return err
	}
	return err
}
{{ end }}