transaction_manager.inc

<?php
class Transaction_Manager extends MySource_Object
{

    private $_rollback = Array();

    private $_levels = Array();


    function Transaction_Manager()
    {
        $this->MySource_Object();

    }//end constructor


    public function inTransaction($db_name)
    {
        return !empty($this->_levels[$db_name]);

    }//end inTransaction()


    public function begin($db_name)
    {
        $dsn_array = MatrixDAL::getDsn($db_name);
        $dsn = $dsn_array['dsn'];
        if (isset($dsn_array['userName'])) $dsn .= ';user='.$dsn_array['userName'];

        if (isset($this->_levels[$dsn])) {
            $this->_levels[$dsn]++;
        } else {
            $this->_levels[$dsn] = 1;
        }

        if ($this->_levels[$dsn] == 1) {
            try {
                MatrixDAL::beginTransaction();
            } catch (DALException $e) {
                throw $e;
            }
        }

        return TRUE;

    }//end begin()


    public function commit($db_name)
    {
        $dsn_array = MatrixDAL::getDsn($db_name);
        $dsn = $dsn_array['dsn'];
        if (isset($dsn_array['userName'])) $dsn .= ';user='.$dsn_array['userName'];

        if (empty($this->_levels[$dsn])) {
            // TODO: -TOF- put that line back
            //trigger_localised_error('SYS0219', E_USER_WARNING);
            return FALSE;
        }

        if (!empty($this->_rollback[$dsn])) {
            trigger_localised_error('SYS0220', E_USER_WARNING);
            try {
                MatrixDAL::rollback();
            } catch (DALException $e) {
                throw $e;
            }

            return FALSE;
        }
        $this->_levels[$dsn]--;

        if ($this->_levels[$dsn] == 0) {
            // this is the last commit
            try {
                MatrixDAL::commit();
            } catch (DALException $e) {
                throw $e;
            }
        }

        return TRUE;

    }//end commit()


    public function rollback($db_name)
    {
        $dsn_array = MatrixDAL::getDsn($db_name);
        $dsn = $dsn_array['dsn'];
        if (isset($dsn_array['userName'])) $dsn .= ';user='.$dsn_array['userName'];

        if (empty($this->_levels[$dsn])) {
            trigger_localised_error('SYS0231', E_USER_WARNING);
            return FALSE;
        }

        // set the rollback flag
        $this->_rollback[$dsn] = TRUE;
        $this->_levels[$dsn]--;

        if ($this->_levels[$dsn] == 0) {

            // this is the last rollback
            try {
                MatrixDAL::rollback();
            } catch (DALException $e) {
                throw $e;
            }

            // clear the rollback flag as there is no more transaction block
            $this->_rollback[$dsn] = FALSE;
        }

        return TRUE;

    }//end rollback()


}//end class
?>