path: root/modules/dblog/dblog.module

<?php
// $Id$

/**
 * @file
 * System monitoring and logging for administrators.
 *
 * The dblog module monitors your site and keeps a list of
 * recorded events containing usage and performance data, errors,
 * warnings, and similar operational information.
 *
 * @see watchdog().
 */

/**
 * Implementation of hook_help().
 */
function dblog_help($path, $arg) {
  switch ($path) {
    case 'admin/help#dblog':
      $output = '<p>'. t('The dblog module monitors your system, capturing system events in a log to be reviewed by an authorized individual at a later time. This is useful for site administrators who want a quick overview of activities on their site. The logs also record the sequence of events, so it can be useful for debugging site errors.') .'</p>';
      $output .= '<p>'. t('The dblog log is simply a list of recorded events containing usage data, performance data, errors, warnings and operational information. Administrators should check the dblog report on a regular basis to ensure their site is working properly.') .'</p>';
      $output .= '<p>'. t('For more information please read the configuration and customization handbook <a href="@dblog">Dblog page</a>.', array('@dblog' => 'http://drupal.org/handbook/modules/dblog/')) .'</p>';
      return $output;
    case 'admin/logs/dblog':
      return '<p>'. t('The dblog module monitors your website, capturing system events in a log to be reviewed by an authorized individual at a later time. The dblog log is simply a list of recorded events containing usage data, performance data, errors, warnings and operational information. It is vital to check the dblog report on a regular basis as it is often the only way to tell what is going on.') .'</p>';
  }
}

/**
 * Implementation of hook_theme()
 */
function dblog_theme() {
  return array(
    'dblog_filters' => array(
      'arguments' => array('form' => NULL),
    ),
  );
}

/**
 * Implementation of hook_menu().
 */
function dblog_menu() {
  $items['admin/settings/logging/dblog'] = array(
    'title' => 'Database logging',
    'description' => 'Settings for logging to the Drupal database logs. This is the most common method for small to medium sites on shared hosting. The logs are viewable from the admin pages.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('dblog_admin_settings'),
  );

  $items['admin/logs/dblog'] = array(
    'title' => 'Recent log entries',
    'description' => 'View events that have recently been logged.',
    'page callback' => 'dblog_overview',
    'weight' => -1,
  );
  $items['admin/logs/page-not-found'] = array(
    'title' => "Top 'page not found' errors",
    'description' => "View 'page not found' errors (404s).",
    'page callback' => 'dblog_top',
    'page arguments' => array('page not found'),
  );
  $items['admin/logs/access-denied'] = array(
      'title' => "Top 'access denied' errors",
    'description' => "View 'access denied' errors (403s).",
    'page callback' => 'dblog_top',
    'page arguments' => array('access denied'),
  );
  $items['admin/logs/event/%'] = array(
    'title' => 'Details',
    'page callback' => 'dblog_event',
    'page arguments' => array(3),
    'type' => MENU_CALLBACK,
  );
  return $items;
}

function dblog_init() {
  if (arg(0) == 'admin' && arg(1) == 'logs') {
    // Add the CSS for this module
    drupal_add_css(drupal_get_path('module', 'dblog') .'/dblog.css', 'module', 'all', FALSE);
  }
}

function dblog_admin_settings() {
  $form['dblog_row_limit'] = array(
    '#type' => 'select',
    '#title' => t('Discard log entries above the following row limit'),
    '#default_value' => variable_get('dblog_row_limit', 1000),
    '#options' => drupal_map_assoc(array(100, 1000, 10000, 100000, 1000000)),
    '#description' => t('The maximum number of rows to keep in the database log. Older entries will be automatically discarded. Requires crontab.')
  );

  return system_settings_form($form);
}

/**
 * Implementation of hook_cron().
 *
 * Remove expired log messages and flood control events.
 */
function dblog_cron() {
  // Cleanup the watchdog table
  $min = db_result(db_query('SELECT MIN(wid) FROM {watchdog}'));
  if ($min) {
    $max = db_result(db_query('SELECT MAX(wid) FROM {watchdog}'));
    if ($max) {
      if (($max - $min) > variable_get('dblog_row_limit', 1000)) {
        db_query('DELETE FROM {watchdog} WHERE wid < %d', $max - $min);
      }
    }
  }
}

/**
 * Implementation of hook_user().
 */
function dblog_user($op, &$edit, &$user) {
  if ($op == 'delete') {
    db_query('UPDATE {watchdog} SET uid = 0 WHERE uid = %d', $user->uid);
  }
}

/**
 * Menu callback; displays a listing of log messages.
 */
function dblog_overview() {
  $filter = dblog_build_filter_query();
  $rows = array();
  $icons = array(
    WATCHDOG_NOTICE  => '',
    WATCHDOG_WARNING => theme('image', 'misc/watchdog-warning.png', t('warning'), t('warning')),
    WATCHDOG_ERROR   => theme('image', 'misc/watchdog-error.png', t('error'), t('error')),
  );
  $classes = array(
    WATCHDOG_NOTICE => 'dblog-notice',
    WATCHDOG_WARNING => 'dblog-warning',
    WATCHDOG_ERROR => 'dblog-error',
  );

  $output = drupal_get_form('dblog_filter_form');

  $header = array(
    ' ',
    array('data' => t('Type'), 'field' => 'w.type'),
    array('data' => t('Date'), 'field' => 'w.wid', 'sort' => 'desc'),
    t('Message'),
    array('data' => t('User'), 'field' => 'u.name'),
    array('data' => t('Operations')),
  );

  $sql = "SELECT w.wid, w.uid, w.severity, w.type, w.timestamp, w.message, w.variables, w.link, u.name FROM {watchdog} w INNER JOIN {users} u ON w.uid = u.uid";
  $tablesort = tablesort_sql($header);
  if (!empty($filter['where'])) {
    $result = pager_query($sql ." WHERE ". $filter['where'] . $tablesort, 50, 0, NULL, $filter['args']);
  }
  else {
    $result = pager_query($sql . $tablesort, 50);
  }

  while ($dblog = db_fetch_object($result)) {
    $rows[] = array('data' =>
      array(
        // Cells
        $icons[$dblog->severity],
        t($dblog->type),
        format_date($dblog->timestamp, 'small'),
        l(truncate_utf8(_dblog_format_message($dblog), 56, TRUE, TRUE), 'admin/logs/event/'. $dblog->wid, array('html' => TRUE)),
        theme('username', $dblog),
        $dblog->link,
      ),
      // Attributes for tr
      'class' => "dblog-". preg_replace('/[^a-z]/i', '-', $dblog->type) .' '. $classes[$dblog->severity]
    );
  }

  if (!$rows) {
    $rows[] = array(array('data' => t('No log messages available.'), 'colspan' => 6));
  }

  $output .= theme('table', $header, $rows, array('id' => 'admin-dblog'));
  $output .= theme('pager', NULL, 50, 0);

  return $output;
}

/**
 * Menu callback; generic function to display a page of the most frequent
 * dblog events of a specified type.
 */
function dblog_top($type) {

  $header = array(
    array('data' => t('Count'), 'field' => 'count', 'sort' => 'desc'),
    array('data' => t('Message'), 'field' => 'message')
  );

  $result = pager_query("SELECT COUNT(wid) AS count, message, variables FROM {watchdog} WHERE type = '%s' GROUP BY message, variables ". tablesort_sql($header), 30, 0, "SELECT COUNT(DISTINCT(message)) FROM {watchdog} WHERE type = '%s'", $type);

  $rows = array();
  while ($dblog = db_fetch_object($result)) {
    $rows[] = array($dblog->count, truncate_utf8(_dblog_format_message($dblog), 56, TRUE, TRUE));
  }

  if (empty($rows)) {
    $rows[] = array(array('data' => t('No log messages available.'), 'colspan' => 2));
  }

  $output  = theme('table', $header, $rows);
  $output .= theme('pager', NULL, 30, 0);

  return $output;
}

/**
 * Menu callback; displays details about a log message.
 */
function dblog_event($id) {
  $severity = watchdog_severity_levels();
  $output = '';
  $result = db_query('SELECT w.*, u.name, u.uid FROM {watchdog} w INNER JOIN {users} u ON w.uid = u.uid WHERE w.wid = %d', $id);
  if ($dblog = db_fetch_object($result)) {
    $rows = array(
      array(
        array('data' => t('Type'), 'header' => TRUE),
        t($dblog->type),
      ),
      array(
        array('data' => t('Date'), 'header' => TRUE),
        format_date($dblog->timestamp, 'large'),
      ),
      array(
        array('data' => t('User'), 'header' => TRUE),
        theme('username', $dblog),
      ),
      array(
        array('data' => t('Location'), 'header' => TRUE),
        l($dblog->location, $dblog->location),
      ),
      array(
        array('data' => t('Referrer'), 'header' => TRUE),
        l($dblog->referer, $dblog->referer),
      ),
      array(
        array('data' => t('Message'), 'header' => TRUE),
        _dblog_format_message($dblog),
      ),
      array(
        array('data' => t('Severity'), 'header' => TRUE),
        $severity[$dblog->severity],
      ),
      array(
        array('data' => t('Hostname'), 'header' => TRUE),
        $dblog->hostname,
      ),
      array(
        array('data' => t('Operations'), 'header' => TRUE),
        $dblog->link,
      ),
    );
    $attributes = array('class' => 'dblog-event');
    $output = theme('table', array(), $rows, $attributes);
  }
  return $output;
}

function _dblog_get_message_types() {
  $types = array();

  $result = db_query('SELECT DISTINCT(type) FROM {watchdog} ORDER BY type');
  while ($object = db_fetch_object($result)) {
    $types[] = $object->type;
  }

  return $types;
}

function dblog_watchdog($log = array()) {
  $current_db = db_set_active();
  db_query("INSERT INTO {watchdog}
    (uid, type, message, variables, severity, link, location, referer, hostname, timestamp)
    VALUES
    (%d, '%s', '%s', '%s', %d, '%s', '%s', '%s', '%s', %d)",
    $log['user']->uid,
    $log['type'],
    $log['message'],
    serialize($log['variables']),
    $log['severity'],
    $log['link'],
    $log['request_uri'],
    $log['referer'],
    $log['ip'],
    $log['timestamp']);

  if ($current_db) {
    db_set_active($current_db);
  }
}

/**
 * Formats a log message for display.
 *
 * @param $dblog
 *   An object with at least the message and variables properties
 */
function _dblog_format_message($dblog) {
  // Legacy messages and user specified text
  if ($dblog->variables === 'N;') {
    return $dblog->message;
  }
  // Message to translate with injected variables
  else {
    return t($dblog->message, unserialize($dblog->variables));
  }
}

/**
 * Return form for dblog administration filters.
 */
function dblog_filter_form() {
  $session = &$_SESSION['dblog_overview_filter'];
  $session = is_array($session) ? $session : array();
  $filters = dblog_filters();

  $form['filters'] = array(
    '#type' => 'fieldset',
    '#title' => t('Filter log messages'),
    '#theme' => 'dblog_filters',
    '#collapsible' => TRUE,
    '#collapsed' => empty($session),
  );
  foreach ($filters as $key => $filter) {
    $form['filters']['status'][$key] = array(
      '#title' => $filter['title'],
      '#type' => 'select',
      '#multiple' => TRUE,
      '#size' => 8,
      '#options' => $filter['options'],
    );
    if (!empty($session[$key])) {
      $form['filters']['status'][$key]['#default_value'] = $session[$key];
    }
  }

  $form['filters']['buttons']['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Filter'),
  );
  if (!empty($session)) {
    $form['filters']['buttons']['reset'] = array(
      '#type' => 'submit',
      '#value' => t('Reset')
    );
  }

  return $form;
}

/**
 * Theme dblog administration filter selector.
 */
function theme_dblog_filters($form) {
  $output = '';
  foreach (element_children($form['status']) as $key) {
    $output .= drupal_render($form['status'][$key]);
  }
  $output .= '<div id="dblog-admin-buttons">'. drupal_render($form['buttons']) .'</div>';
  return $output;
}

function dblog_filter_form_validate($form, &$form_state) {
  if ($form_state['values']['op'] == t('Filter') && empty($form_state['values']['type']) && empty($form_state['values']['severity'])) {
    form_set_error('type', t('You must select something to filter by.'));
  }
}

/**
 * Process result from dblog administration filter form.
 */
function dblog_filter_form_submit($form, &$form_state) {
  $op = $form_state['values']['op'];
  $filters = dblog_filters();
  switch ($op) {
    case t('Filter'):
      foreach ($filters as $name => $filter) {
        if (isset($form_state['values'][$name])) {
          $_SESSION['dblog_overview_filter'][$name] = $form_state['values'][$name];
        }
      }
      break;
    case t('Reset'):
      $_SESSION['dblog_overview_filter'] = array();
      break;
  }
  return 'admin/logs/dblog';
}

/**
 * List dblog administration filters that can be applied.
 */
function dblog_filters() {
  $filters = array();

  foreach(_dblog_get_message_types() as $type) {
    $types[$type] = $type;
  }

  if (!empty($types)) {
    $filters['type'] = array(
      'title' => t('Type'),
      'where' => "w.type = '%s'",
      'options' => $types,
    );
  }

  $filters['severity'] = array(
    'title' => t('Severity'),
    'where' => 'w.severity = %d',
    'options' => watchdog_severity_levels(),
  );

  return $filters;
}

/**
 * Build query for dblog administration filters based on session.
 */
function dblog_build_filter_query() {
  if (empty($_SESSION['dblog_overview_filter'])) {
    return;
  }

  $filters = dblog_filters();

  // Build query
  $where = $args = array();
  foreach ($_SESSION['dblog_overview_filter'] as $key => $filter) {
    $filter_where = array();
    foreach ($filter as $value) {
      $filter_where[] = $filters[$key]['where'];
      $args[] = $value;
    }
    if (!empty($filter_where)) {
      $where[] = '('. implode(' OR ', $filter_where) .')';
    }
  }
  $where = !empty($where) ? implode(' AND ', $where) : '';

  return array(
    'where' => $where,
    'args' => $args,
  );
}