class Log

Same name in this branch
  1. 11.x core/modules/migrate/src/Plugin/migrate/process/Log.php \Drupal\migrate\Plugin\migrate\process\Log
Same name in other branches
  1. 9 core/modules/migrate/src/Plugin/migrate/process/Log.php \Drupal\migrate\Plugin\migrate\process\Log
  2. 9 core/lib/Drupal/Core/Database/Log.php \Drupal\Core\Database\Log
  3. 8.9.x core/modules/migrate/src/Plugin/migrate/process/Log.php \Drupal\migrate\Plugin\migrate\process\Log
  4. 8.9.x core/lib/Drupal/Core/Database/Log.php \Drupal\Core\Database\Log
  5. 10 core/modules/migrate/src/Plugin/migrate/process/Log.php \Drupal\migrate\Plugin\migrate\process\Log
  6. 10 core/lib/Drupal/Core/Database/Log.php \Drupal\Core\Database\Log

Database query logger.

We log queries in a separate object rather than in the connection object because we want to be able to see all queries sent to a given database, not database target. If we logged the queries in each connection object we would not be able to track what queries went to which target.

Every connection has one and only one logging object on it for all targets and logging keys.

Hierarchy

  • class \Drupal\Core\Database\Log

Expanded class hierarchy of Log

1 file declares its use of Log
StubConnection.php in core/tests/Drupal/Tests/Core/Database/Stub/StubConnection.php
17 string references to 'Log'
ConnectionTest::providerMockedBacktrace in core/tests/Drupal/Tests/Core/Database/ConnectionTest.php
Provides data for testFindCallerFromDebugBacktraceWithMockedBacktrace.
d6_node.yml in core/modules/node/migrations/d6_node.yml
core/modules/node/migrations/d6_node.yml
d6_node_complete.yml in core/modules/node/migrations/d6_node_complete.yml
core/modules/node/migrations/d6_node_complete.yml
d6_node_revision.yml in core/modules/node/migrations/d6_node_revision.yml
core/modules/node/migrations/d6_node_revision.yml
d6_node_translation.yml in core/modules/content_translation/migrations/d6_node_translation.yml
core/modules/content_translation/migrations/d6_node_translation.yml

... See full list

File

core/lib/Drupal/Core/Database/Log.php, line 18

Namespace

Drupal\Core\Database
View source
class Log {
    
    /**
     * Cache of logged queries. This will only be used if the query logger is enabled.
     *
     * The structure for the logging array is as follows:
     *
     * array(
     *   $logging_key = array(
     *     array('query' => '', 'args' => array(), 'caller' => '', 'target' => '', 'time' => 0, 'start' => 0),
     *     array('query' => '', 'args' => array(), 'caller' => '', 'target' => '', 'time' => 0, 'start' => 0),
     *   ),
     * );
     *
     * @var array
     */
    protected $queryLog = [];
    
    /**
     * The connection key for which this object is logging.
     *
     * @var string
     */
    protected $connectionKey = 'default';
    
    /**
     * Constructor.
     *
     * @param $key
     *   The database connection key for which to enable logging.
     */
    public function __construct($key = 'default') {
        $this->connectionKey = $key;
    }
    
    /**
     * Begin logging queries to the specified connection and logging key.
     *
     * If the specified logging key is already running this method does nothing.
     *
     * @param $logging_key
     *   The identification key for this log request. By specifying different
     *   logging keys we are able to start and stop multiple logging runs
     *   simultaneously without them colliding.
     */
    public function start($logging_key) {
        if (empty($this->queryLog[$logging_key])) {
            $this->clear($logging_key);
        }
    }
    
    /**
     * Retrieve the query log for the specified logging key so far.
     *
     * @param $logging_key
     *   The logging key to fetch.
     *
     * @return array
     *   An indexed array of all query records for this logging key.
     */
    public function get($logging_key) {
        return $this->queryLog[$logging_key];
    }
    
    /**
     * Empty the query log for the specified logging key.
     *
     * This method does not stop logging, it simply clears the log. To stop
     * logging, use the end() method.
     *
     * @param $logging_key
     *   The logging key to empty.
     */
    public function clear($logging_key) {
        $this->queryLog[$logging_key] = [];
    }
    
    /**
     * Stop logging for the specified logging key.
     *
     * @param $logging_key
     *   The logging key to stop.
     */
    public function end($logging_key) {
        unset($this->queryLog[$logging_key]);
    }
    
    /**
     * Log a query to all active logging keys, from a statement execution event.
     *
     * @param \Drupal\Core\Database\Event\StatementExecutionEndEvent $event
     *   The statement execution event.
     */
    public function logFromEvent(StatementExecutionEndEvent $event) : void {
        foreach (array_keys($this->queryLog) as $key) {
            $this->queryLog[$key][] = [
                'query' => $event->queryString,
                'args' => $event->args,
                'target' => $event->target,
                'caller' => $event->caller,
                'time' => $event->getElapsedTime(),
                'start' => $event->startTime,
            ];
        }
    }

}

Members

Title Sort descending Modifiers Object type Summary
Log::$connectionKey protected property The connection key for which this object is logging.
Log::$queryLog protected property Cache of logged queries. This will only be used if the query logger is enabled.
Log::clear public function Empty the query log for the specified logging key.
Log::end public function Stop logging for the specified logging key.
Log::get public function Retrieve the query log for the specified logging key so far.
Log::logFromEvent public function Log a query to all active logging keys, from a statement execution event.
Log::start public function Begin logging queries to the specified connection and logging key.
Log::__construct public function Constructor.

Buggy or inaccurate documentation? Please file an issue. Need support? Need help programming? Connect with the Drupal community.