lib/API.php
protected function log_message($message, $priority_level = self::LOG_DEBUG)
    {
        if (
            $this->DEBUG &&
            $this->API_DEBUG_HANDLER &&
            is_callable($this->API_DEBUG_HANDLER)
        ) {
            $response = call_user_func($this->API_DEBUG_HANDLER, $message, $priority_level);
        } else {
            $response = error_log($message);
        }

        return $response;
    }
protected function log_message($message, $priority_level = self::LOG_DEBUG)
    {
        if (
            $this->DEBUG &&
            $this->API_DEBUG_HANDLER &&
            is_callable($this->API_DEBUG_HANDLER)
        ) {
            $response = call_user_func($this->API_DEBUG_HANDLER, $message, $priority_level);
        } else {
            $response = error_log($message);
        }

        return $response;
    }
protected function log_message ( $ message , $ priority_level = self :: LOG_DEBUG ) { if ( $ this -> DEBUG && $ this -> API_DEBUG_HANDLER && is_callable ( $ this -> API_DEBUG_HANDLER ) ) { $ response = call_user_func ( $ this -> API_DEBUG_HANDLER , $ message , $ priority_level ) ; } else { $ response = error_log ( $ message ) ; } return $ response ; }
Log debug messages using the custom handler passed as an option in the constructor.
If not handler is defined it falls back to using 'error_log'.

@param $message string the logged message
@param string $priority_level based on syslog priority levels http://php.net/manual/en/function.syslog.php
@return bool true on success or false on failure
Log debug messages using the custom handler passed as an option in the constructor . If not handler is defined it falls back to using error_log .