dblog.module

Same filename and directory in other branches
  1. 7.x modules/dblog/dblog.module
  2. 9 core/modules/dblog/dblog.module
  3. 8.9.x core/modules/dblog/dblog.module
  4. 10 core/modules/dblog/dblog.module

System monitoring and logging for administrators.

The Database Logging module monitors your site and keeps a list of recorded events containing usage and performance data, errors, warnings, and similar operational information.

File

core/modules/dblog/dblog.module

View source
<?php


/**
 * @file
 * System monitoring and logging for administrators.
 *
 * The Database Logging module monitors your site and keeps a list of recorded
 * events containing usage and performance data, errors, warnings, and similar
 * operational information.
 */
use Drupal\Core\Url;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Routing\RouteMatchInterface;
use Drupal\Core\StringTranslation\TranslatableMarkup;
use Drupal\views\ViewExecutable;

/**
 * Implements hook_help().
 */
function dblog_help($route_name, RouteMatchInterface $route_match) {
    switch ($route_name) {
        case 'help.page.dblog':
            $output = '';
            $output .= '<h2>' . t('About') . '</h2>';
            $output .= '<p>' . t('The Database Logging module logs system events in the Drupal database. For more information, see the <a href=":dblog">online documentation for the Database Logging module</a>.', [
                ':dblog' => 'https://www.drupal.org/documentation/modules/dblog',
            ]) . '</p>';
            $output .= '<h2>' . t('Uses') . '</h2>';
            $output .= '<dl>';
            $output .= '<dt>' . t('Monitoring your site') . '</dt>';
            $output .= '<dd>' . t('The Database Logging module allows you to view an event log on the <a href=":dblog">Recent log messages</a> page. The log is a chronological list of recorded events containing usage data, performance data, errors, warnings and operational information. Administrators should check the log on a regular basis to ensure their site is working properly.', [
                ':dblog' => Url::fromRoute('dblog.overview')->toString(),
            ]) . '</dd>';
            $output .= '<dt>' . t('Debugging site problems') . '</dt>';
            $output .= '<dd>' . t('In case of errors or problems with the site, the <a href=":dblog">Recent log messages</a> page can be useful for debugging, since it shows the sequence of events. The log messages include usage information, warnings, and errors.', [
                ':dblog' => Url::fromRoute('dblog.overview')->toString(),
            ]) . '</dd>';
            $output .= '<dt>' . t('This log is not persistent') . '</dt>';
            $output .= '<dd>' . t('The Database Logging module logs may be cleared by administrators and automated cron tasks, so they should not be used for <a href=":audit_trail_wiki">forensic logging</a>. For forensic purposes, use the Syslog module.', [
                ':audit_trail_wiki' => 'https://en.wikipedia.org/wiki/Audit_trail',
            ]) . '</dd>';
            $output .= '</dl>';
            return $output;
        case 'dblog.overview':
            return '<p>' . t('The Database Logging module logs system events in the Drupal database. Monitor your site or debug site problems on this page.') . '</p>';
    }
}

/**
 * Implements hook_menu_links_discovered_alter().
 */
function dblog_menu_links_discovered_alter(&$links) {
    if (\Drupal::moduleHandler()->moduleExists('search')) {
        $links['dblog.search'] = [
            'title' => new TranslatableMarkup('Top search phrases'),
            'route_name' => 'dblog.search',
            'description' => new TranslatableMarkup('View most popular search phrases.'),
            'parent' => 'system.admin_reports',
        ];
    }
    return $links;
}

/**
 * Implements hook_cron().
 *
 * Controls the size of the log table, paring it to 'dblog_row_limit' messages.
 */
function dblog_cron() {
    // Cleanup the watchdog table.
    $row_limit = \Drupal::config('dblog.settings')->get('row_limit');
    // For row limit n, get the wid of the nth row in descending wid order.
    // Counting the most recent n rows avoids issues with wid number sequences,
    // e.g. auto_increment value > 1 or rows deleted directly from the table.
    if ($row_limit > 0) {
        $connection = \Drupal::database();
        $min_row = $connection->select('watchdog', 'w')
            ->fields('w', [
            'wid',
        ])
            ->orderBy('wid', 'DESC')
            ->range($row_limit - 1, 1)
            ->execute()
            ->fetchField();
        // Delete all table entries older than the nth row, if nth row was found.
        if ($min_row) {
            $connection->delete('watchdog')
                ->condition('wid', $min_row, '<')
                ->execute();
        }
    }
}

/**
 * Gathers a list of uniquely defined database log message types.
 *
 * @return array
 *   List of uniquely defined database log message types.
 */
function _dblog_get_message_types() {
    return \Drupal::database()->query('SELECT DISTINCT([type]) FROM {watchdog} ORDER BY [type]')
        ->fetchAllKeyed(0, 0);
}

/**
 * Implements hook_form_FORM_ID_alter() for system_logging_settings().
 */
function dblog_form_system_logging_settings_alter(&$form, FormStateInterface $form_state) {
    $row_limits = [
        100,
        1000,
        10000,
        100000,
        1000000,
    ];
    $form['dblog_row_limit'] = [
        '#type' => 'select',
        '#title' => t('Database log messages to keep'),
        '#config_target' => 'dblog.settings:row_limit',
        '#options' => [
            0 => t('All'),
        ] + array_combine($row_limits, $row_limits),
        '#description' => t('The maximum number of messages to keep in the database log. Requires a <a href=":cron">cron maintenance task</a>.', [
            ':cron' => Url::fromRoute('system.status')->toString(),
        ]),
    ];
}

/**
 * Implements hook_views_pre_render().
 */
function dblog_views_pre_render(ViewExecutable $view) {
    if (isset($view) && $view->storage
        ->get('base_table') == 'watchdog') {
        $view->element['#attached']['library'][] = 'dblog/drupal.dblog';
    }
}

Functions

Title Deprecated Summary
dblog_cron Implements hook_cron().
dblog_form_system_logging_settings_alter Implements hook_form_FORM_ID_alter() for system_logging_settings().
dblog_help Implements hook_help().
dblog_menu_links_discovered_alter Implements hook_menu_links_discovered_alter().
dblog_views_pre_render Implements hook_views_pre_render().
_dblog_get_message_types Gathers a list of uniquely defined database log message types.

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