Passing an exception as the message to Zend_Log_Writer_Db raises an exception

[zfbot]

Jira Information

Original Issue:	ZF-12435
Issue Type:	Bug
Reporter:	Andrew Ballard
Created:	10/04/12
Assignee:	froschdesign
Components:	Zend_Log

Description

The other log writers allow you to pass an instance of an exception as the message for logging. In particular, Zend_Log_Writer_Firebug even has a formatter that renders in a way that is easy to read when debugging XmlHttpRequests. However, I get an exception in Zend_Log_Writer_Db because the message is an object:

exception 'Zend_Db_Statement_Sqlsrv_Exception' with message 'An invalid PHP type for parameter 4 was specified.' in ..\library\Zend\Db\Statement\Sqlsrv.php:206 
Stack trace: 
#0 ..\library\Zend\Db\Statement.php(320): Zend_Db_Statement_Sqlsrv->_execute(Array) 
#1 ..\library\Zend\Db\Adapter\Abstract.php(479): Zend_Db_Statement->execute(Array) 
#2 ..\library\Zend\Db\Adapter\Sqlsrv.php(380): Zend_Db_Adapter_Abstract->query('INSERT INTO "Ap...', Array) 
#3 ..\library\Zend\Log\Writer\Db.php(143): Zend_Db_Adapter_Sqlsrv->insert('ApplicationLog', Array) 
#4 ..\library\Zend\Log\Writer\Abstract.php(85): Zend_Log_Writer_Db->_write(Array) 
#5 ..\library\Zend\Log.php(428): Zend_Log_Writer_Abstract->write(Array) 
#6 [internal function]: Zend_Log->log(Object(Exception), 3) 
#7 ..\library\My\Controller\Plugin\Log.php(212): call_user_func_array(Array, Array) 
#8 [internal function]: My_Controller_Plugin_Log->__call('log', Array) 
#9 [internal function]: My_Controller_Plugin_Log->log(Object(Exception), 3) 
#10 ..\library\My\Controller\Action\Helper\Log.php(27): call_user_func_array(Array, Array) 
#11 ..\application\controllers\ErrorController.php(52): My_Controller_Action_Helper_Log->__call('log', Array) 
#12 ..\application\controllers\ErrorController.php(52): My_Controller_Action_Helper_Log->log(Object(Exception), 3) 
#13 ..\library\Zend\Controller\Action.php(516): ErrorController->errorAction() 
#14 ..\library\Zend\Controller\Dispatcher\Standard.php(295): Zend_Controller_Action->dispatch('errorAction') 
#15 ..\library\Zend\Controller\Front.php(954): Zend_Controller_Dispatcher_Standard->dispatch(Object(Zend_Controller_Request_Http), Object(Zend_Controller_Response_Http)) 
#16 ..\library\Zend\Application\Bootstrap\Bootstrap.php(97): Zend_Controller_Front->dispatch() 
#17 ..\library\Zend\Application.php(366): Zend_Application_Bootstrap_Bootstrap->run() 
#18 ..\public\index.php(126): Zend_Application->run() 
#19 \{main\}

I can pass the exception in as a string, but then it is more difficult to read in Firebug. I'm also not sure if this problem is specific to the database adapter I am using (Zend_Db_Adapter_Sqlsrv) since I don't have another database/adapter I can test right now.

I think a change in Zend_Log_Writer_Db::_write() should fix it but I don't know if it might raise other issues:

    /**
     * Write a message to the log.
     *
     * @param  array  $event  event data
     * @return void
     * @throws Zend_Log_Exception
     */
    protected function _write($event)
    {
        if ($this->_db === null) {
            // require_once 'Zend/Log/Exception.php';
            throw new Zend_Log_Exception('Database adapter is null');
        }

        if ($this->_columnMap === null) {
            $dataToInsert = $event;
        } else {
            $dataToInsert = array();
            foreach ($this->_columnMap as $columnName => $fieldKey) {
-                $dataToInsert[$columnName] = $event[$fieldKey];

+               if ('info' == $fieldKey && (is_object($event[$fieldKey]) || is_array($event[$fieldKey]))) {
+                   $dataToInsert[$columnName] = Zend_Debug::dump($event[$fieldKey], gettype($event[$fieldKey]), true);
+               } else {
+                   $dataToInsert[$columnName] = $event[$fieldKey];
+               }
            }
        }

        $this->_db->insert($this->_table, $dataToInsert);
    }

I tried to resolve this by extending Zend_Log_Writer_Db to override the _write method, but all of the properties are marked private instead of protected for some reason. As a result, getting it to work would have required duplicating the entire class. (If they truly need to be private, perhaps the class should be final?)

[zfbot]

(Originally posted by: Andrew Ballard on 10/04/12)

Fixed code block.

[zfbot]

(Originally posted by: froschdesign on 02/15/13)

Hi Andrew,
I will look into your problem with exceptions. I must write a unit test.

{quote} tried to resolve this by extending Zend_Log_Writer_Db to override the _write method, but all of the properties are marked private instead of protected for some reason.{quote}
This problem was fixed with ZF-12514. ([Look at the diff|http://framework.zend.com/code/diff.php?repname=Zend+Framework&path=%2Fbranches%2Frelease-1.12%2Flibrary%2FZend%2FLog%2FWriter%2FDb.php&rev=25247&peg=25247])

Thanks for your help! :)

[zfbot]

(Originally posted by: Andrew Ballard on 02/15/13)

{quote}
bq. tried to resolve this by extending Zend_Log_Writer_Db to override the _write method, but all of the properties are marked private instead of protected for some reason.

This problem was fixed with ZF-12514.{quote}

Thank you!

I was ultimately able to extend {{Zend_Log_Writer_Db}} in a way that works with the current version. I'm still not sure if this is the best way of handling things, but this is the class I came up with:

/**
 * @category   My
 * @package    My_Log
 * @subpackage Writer
 */
class My_Log_Writer_Db extends Zend_Log_Writer_Db
{

    /**
     * Relates database columns names to log data field keys.
     * 
     * THIS HAD TO BE COPIED TO THE SUBCLASS BECAUSE IT WAS DECLARED PRIVATE IN
     * THE PARENT CLASS AND I NEED IT IN THE OVERRIDDEN _write METHOD BELOW. 
     * 
     * @var null|array
     */
    private $_columnMap;

    /**
     * Class constructor
     * 
     * THIS HAD TO BE INCLUDED BECAUSE $db, $table AND $columnMap ALL  MAP TO 
     * PRIVATE PROPERTIES IN THE PARENT CLASS AND COULD NOT BE SET HERE.
     *
     * @param Zend_Db_Adapter $db   Database adapter instance
     * @param string $table         Log table in database
     * @param array $columnMap
     * @return void
     */
    public function __construct($db, $table, $columnMap = null)
    {

        // I NEED $columnMap IN THE OVERRIDDEN VERSION OF _write BELOW.
        $this->_columnMap = $columnMap;

        // PASS ALL THE PARAMETERS TO THE PARENT CLASS SO THEY CAN BE SET 
        // CORRECTLY WHERE _write IN THE PARENT CLASS CAN ACCESS THEM.
        parent::__construct($db, $table, $columnMap);
    }


    /**
     * Write a message to the log.
     * OVERWRITTEN: Safely converts any values in the $event to strings 
     *
     * @param  array  $event  event data
     * @return void
     * @throws Zend_Log_Exception
     */
    protected function _write($event)
    {

        foreach ($this->_columnMap as $columnName => $fieldKey) {

            $var = $event[$fieldKey];

            switch (true) {

                case ('message' == $fieldKey && ($var instanceof Exception)):
                    // Special handling if an exception was passed to the
                    // message.

                    // Store only the exception message in 'message'.

                    // If no 'info' key exists in the event, move the exception
                    // object (cast as a string) to that key.

                    if (!array_key_exists('info', $event)) {
                        $event['info'] = (string) $var; 
                    }
                    $var = $var->getMessage();
                    break; 

                case (is_object($var) && method_exists($var, '__toString()')):
                    // The object can be typecast to a string.
                    // Fall through.
                case is_bool($var):
                case is_numeric($var):
                    $var = (string) $var;
                    break;


                case ($var instanceof DateTime):
                    // DateTime instances cannot be cast to a string.
                    // Format the date as an ISO 8601 string.
                    $var = $var->format('c');
                    break;

                case is_resource($var):
                case is_array($var):
                case is_object($var):
                    // The variable cannot be typecast to a string.
                    $var = Zend_Debug::dump($var, null, true);
                    break;

                case is_string($var):
                    // No action needed; included for completeness.
                    break;

                default:
                    // Not sure what other types might need to be handled.

            }

            $event[$fieldKey] = $var;
        }

        parent::_write($event);
    }
}

Hopefully this is useful to someone else.

[zfbot]

This issue was ported from the ZF2 Jira Issue Tracker at
http://framework.zend.com/issues/browse/ZF-12435

Known GitHub users mentioned in the original message or comment:
@froschdesign

[fusioned]

I've recently had to extend the DB writer _write() method to fix issues with omitted event items. However as this touches on the private _columnMap, this has meant every method which uses this property needed to be overridden.

If the intention was to encourage downstream DB writer classes to be a direct offshoot of the abstract class with entire methods copied from Zend_Log_Writer_Db, _columnMap being private is doing the job.

[froschdesign]

I think, it was fixed with 2882bc7 and released with 1.12.5.

If I've missed something, please feel free to reopen this issue.