jsonlog.module in JSONlog 7.2

JSONlog module.

File

jsonlog.module

<?php

/**
 * @file
 * JSONlog module.
 */

/**
 * Default max. length of a log entry, in kilobytes.
 *
 * @type integer
 */
define('JSONLOG_TRUNCATE_DEFAULT', 64);

/**
 * Adds this module's setting fields to the system logging settings form.
 *
 * Implements hook_form_FORM_ID_alter().
 *
 * Function body relayed to include file, because it's lengthy.
 *
 * @see _jsonlog_form_system_logging_settings_alter()
 *
 * @param array &$form
 * @param array &$form_state
 */
function jsonlog_form_system_logging_settings_alter(&$form, &$form_state) {
  module_load_include('inc', 'jsonlog');
  return _jsonlog_form_system_logging_settings_alter($form, $form_state);
}

/**
 * @param array $form
 * @param array $form_state
 */
function jsonlog_form_system_logging_settings_validate($form, $form_state) {
  $values =& $form_state['values'];

  // Non-empty truncate must be non-negative integer.
  if ($values['jsonlog_truncate'] !== '' && ($value = trim($values['jsonlog_truncate'])) !== '') {
    if (!preg_match('/^\\d+$/', $value)) {
      form_set_error('jsonlog_truncate', t('\'@field\' is not a non-negative integer.', array(
        '@field' => t('Truncate events to'),
      )));
    }
  }
}

/**
 * Custom submit handler for the system logging settings form.
 *
 * @param array $form
 * @param array $form_state
 */
function jsonlog_form_system_logging_settings_submit($form, &$form_state) {
  module_load_include('inc', 'jsonlog');
  $values =& $form_state['values'];
  $fields = array(
    'jsonlog_severity_threshold',
    'jsonlog_truncate',
    'jsonlog_siteid',
    'jsonlog_dir',
    'jsonlog_file_time',
  );
  foreach ($fields as $name) {

    // Trim all values.
    $values[$name] = trim($values[$name]);
  }
  if (!$values['jsonlog_truncate']) {
    $values['jsonlog_truncate'] = 0;
  }
  if (!$values['jsonlog_dir']) {
    $values['jsonlog_dir'] = jsonlog_default_dir();
  }

  // Tags.
  if (($values['jsonlog_tags'] = $v = trim($values['jsonlog_tags'])) !== '') {
    $v = str_replace(array(
      "\r",
      "\n",
    ), '', $v);
    if ($v !== '') {
      if ($v[0] === ',') {
        $v = substr($v, 1);
      }
      if ($v !== '') {
        if ($v[strlen($v) - 1] === ',') {
          $v = substr($v, 0, strlen($v) - 1);
        }
      }
      if (strpos($v, ',')) {
        $v = preg_replace('/ *, */', ',', $v);
      }
    }
    $values['jsonlog_tags'] = trim($v);
  }

  // Test.
  if ($values['jsonlog_test_filing'] && $values['jsonlog_siteid'] && $values['jsonlog_dir'] && $values['jsonlog_file_time']) {
    module_load_include('inc', 'jsonlog');
    jsonlog_test_filing($values['jsonlog_dir'] . '/' . $values['jsonlog_siteid'] . ($values['jsonlog_file_time'] == 'none' ? '' : '.' . date($values['jsonlog_file_time'])) . '.json.log');
  }

  // Don't ever save that field.
  unset($form_state['input']['jsonlog_test_filing'], $values['jsonlog_test_filing']);
}

/**
 * Logs any watchdog call - at or above a certain severity threshold - as JSON
 * to a custom log file.
 *
 * Default severity threshold: warning.
 *
 * Prefers server environment variables for Drupal conf variables.
 * Any jsonlog conf variable may be overridden by a 'drupal_[jsonlog variable]'
 * server environment var.
 *
 *  JSON fields (watchdog standard fields are not explained here):
 *  - \@timestamp: ISO-8601 milliseconds timestamp instead of watchdog's native
 *    seconds timestamp
 *  - \@version: (always) 1
 *  - message_id: jsonlog site ID + unique padding
 *  - site_id: (default) server's hostname + database name + database prefix
 *    (if any)
 *  - tags: comma-separated list; becomes array
 *  - type
 *  - severity
 *  - method: HTTP request method, or 'cli' (if drush)
 *  - request_uri
 *  - referer
 *  - uid
 *  - username: name of current user, or empty
 *  - client_ip: equivalent to watchdog standard 'ip' field
 *  - link
 *  - variables: watchdog standard, except null if empty
 *  - trunc: null if the log entry as a whole doesn't exceed the json_truncate
 *    setting; otherwise array of original length, truncated length
 *
 * Implements hook_watchdog().
 *
 * @param array $log_entry
 */
function jsonlog_watchdog(array $log_entry) {
  static $_threshold, $_site_id, $_canonical, $_file, $_truncate, $_severity, $_tags;

  // Don't load more settings than threshold, in case current entry isn't
  // sufficiently severe.
  if (!$_threshold) {

    // A threshold of zero (emergency) wouldnt make sense in the real world,
    // so no reason to check by type (boolean).
    if (!($_threshold = getenv('drupal_jsonlog_severity_threshold'))) {
      $_threshold = variable_get('jsonlog_severity_threshold', WATCHDOG_WARNING);
    }
  }

  // Severity is upside down; less is more.
  if ($log_entry['severity'] > $_threshold) {
    return;
  }

  // Load the rest of the settings.
  if (!$_site_id) {

    // Site ID: Try server environment var before Drupal conf. var.
    if (!($_site_id = getenv('drupal_jsonlog_siteid'))) {
      if (!($_site_id = variable_get('jsonlog_siteid'))) {
        module_load_include('inc', 'jsonlog');
        variable_set('jsonlog_siteid', $_site_id = jsonlog_default_site_id());
      }
    }

    // Canonical site identifier across site instances.
    if (!($_canonical = getenv('drupal_jsonlog_canonical'))) {
      $_canonical = variable_get('jsonlog_canonical', '');
    }

    // Dir.
    if (!($dir = getenv('drupal_jsonlog_dir'))) {
      if (!($dir = variable_get('jsonlog_dir'))) {
        module_load_include('inc', 'jsonlog');
        if ($dir = jsonlog_default_dir()) {
          variable_set('jsonlog_dir', $dir);
        }
        else {
          error_log('Drupal jsonlog, site ID[' . $_site_id . '], failed to establish server\'s default log dir.');
        }
      }
    }

    // File timestamp.
    if (!($file_time = getenv('drupal_jsonlog_file_time'))) {
      $file_time = variable_get('jsonlog_file_time', 'Ymd');
    }
    $_file = $dir . '/' . $_site_id . ($file_time == 'none' ? '' : '.' . date($file_time)) . '.json.log';

    // Truncation: Try server environment var before Drupal conf. var.
    if (($_truncate = getenv('drupal_jsonlog_truncate')) === FALSE) {
      $_truncate = variable_get('jsonlog_truncate', JSONLOG_TRUNCATE_DEFAULT);
    }
    if ($_truncate) {

      // Kb to bytes.
      $_truncate *= 1024;

      // Substract estimated max length of everything but message content.
      $_truncate -= 768;

      // Message will get longer when JSON encoded, because of hex encoding of
      // <>&" chars.
      $_truncate *= 7 / 8;
    }
    $_severity = array(
      'emergency',
      'alert',
      'critical',
      'error',
      'warning',
      'notice',
      'info',
      'debug',
    );

    // Tags: append Drupal conf. var to server env. var.
    $tags_server = ($tags = getenv('drupal_jsonlog_tags')) !== FALSE ? $tags : '';
    $tags_site = variable_get('jsonlog_tags', '');
    if ($tags_server) {
      $tags = $tags_server;
      if ($tags_site) {
        $tags .= ',' . $tags_site;
      }
    }
    else {
      $tags = $tags_site;
    }
    if ($tags) {
      $_tags = explode(',', $tags);
    }
  }

  // Create the entry.
  $entry = new stdClass();
  $truncation = NULL;
  if ($message = $log_entry['message']) {

    // Replace variables.
    if ($variables = $log_entry['variables']) {

      // Doesnt use format_string() because we don't want HTML placeholder tags.
      foreach ($variables as $key => $value) {
        if ($key[0] != '!') {
          $variables[$key] = check_plain($value);
        }
      }
      $message = strtr($message, $variables);
      unset($variables);
    }

    // Strip tags if message starts with < (Inspect logs in tag).
    if ($message[0] === '<') {
      $message = strip_tags($message);
    }

    // Escape null byte.
    $message = str_replace("\0", '_NUL_', $message);

    // Truncate message.
    // Deliberately multibyte length.
    if ($_truncate && ($le = strlen($message)) > $_truncate) {

      // Truncate multibyte safe until ASCII length is equal to/less than max.
      // byte length.
      $truncation = array(
        $le,
        strlen($message = drupal_truncate_bytes($message, (int) $_truncate)),
      );
    }
  }
  $entry->message = $message;
  unset($message);

  // Use a milliseconds timestamp instead of watchdog()'s seconds timestamp.
  $millis = round(microtime(TRUE) * 1000);
  $seconds = (int) floor($millis / 1000);
  $millis -= $seconds * 1000;
  $millis = str_pad($millis, 3, '0', STR_PAD_LEFT);
  $entry->{'@timestamp'} = substr(gmdate('c', $seconds), 0, 19) . '.' . $millis . 'Z';
  $entry->{'@version'} = 1;
  $entry->message_id = uniqid($_site_id, TRUE);
  $entry->site_id = $_site_id;
  $entry->canonical = $_canonical;
  $entry->tags = $_tags;
  $entry->type = 'drupal';
  $entry->subtype = $log_entry['type'];
  $entry->severity = $_severity[$log_entry['severity']];
  $entry->method = !empty($_SERVER['REQUEST_METHOD']) ? $_SERVER['REQUEST_METHOD'] : 'cli';
  $entry->request_uri = $log_entry['request_uri'];
  $entry->referer = $log_entry['referer'];
  $entry->uid = $uid = $log_entry['uid'];
  $entry->username = $uid && !empty($GLOBALS['user']->name) ? $GLOBALS['user']->name : '';
  $entry->client_ip = $log_entry['ip'];

  // If link is an integer (or 'integer') it may be an event/error code;
  // the Inspect module exploits link for that purpose.
  if (!($link = $log_entry['link'])) {
    $entry->link = NULL;
    $entry->code = 0;
  }
  elseif (ctype_digit($link)) {
    $entry->link = NULL;
    $entry->code = (int) $link;
  }
  else {
    $entry->link = strip_tags($link);
    $entry->code = 0;
  }

  // Since message/variables replacement was implemented, variables will always
  // be empty. A bit silly to keep the variables property at all then, but for
  // backwards compatibility - and the fact that folks might expect the
  // property to exist because it's part the of the hook_watchdog() properties
  // - we keep setting it.
  $entry->variables = NULL;
  $entry->trunc = $truncation;

  // File append, using lock (write, doesn't prevent reading).
  // If failure: log filing error to web server's default log.
  if (!file_put_contents($_file, "\n" . drupal_json_encode($entry), FILE_APPEND | LOCK_EX)) {
    error_log('Drupal jsonlog, site ID[' . $_site_id . '], failed to write to file[' . $_file . '].');
  }
}

Functions

Name	Description
jsonlog_form_system_logging_settings_alter	Adds this module's setting fields to the system logging settings form.
jsonlog_form_system_logging_settings_submit	Custom submit handler for the system logging settings form.
jsonlog_form_system_logging_settings_validate	_state
jsonlog_watchdog	Logs any watchdog call - at or above a certain severity threshold - as JSON to a custom log file.

Constants

Name	Description
JSONLOG_TRUNCATE_DEFAULT	Default max. length of a log entry, in kilobytes.