session_cache_file.module in Session Cache API 8

session_cache_file.module

Provides a file storage implementation for the Session Cache API. More than anything for demonstration and debugging purporses as it is easy to follow on the file system when the caches are written and expired, i.e. when the underlying files are updated and removed.

See the session_cache/README.txt for more info.

File

session_cache_file/session_cache_file.module

<?php

/**
 * @file
 * session_cache_file.module
 *
 * Provides a file storage implementation for the Session Cache API.
 * More than anything for demonstration and debugging purporses as it is easy
 * to follow on the file system when the caches are written and expired,
 * i.e. when the underlying files are updated and removed.
 *
 * See the session_cache/README.txt for more info.
 */
const SESSION_CACHE_STORAGE_FILE = 5;

/*
 * Implements hook_form_FORMID_alter().
 */
function session_cache_file_form_session_cache_settings_alter(&$form, &$form_state) {
  $form['storage_method']['#options'][SESSION_CACHE_STORAGE_FILE] = t('on the server, as a small file');
}
function session_cache_file_directory($bin = NULL) {
  $path = config('system.file')
    ->get('path.private');

  // typically: sites/default/files/private
  if (empty($path)) {
    drupal_set_message(t('Session Cache File: the <strong>Private file system path</strong> is not set. Please configure it <a href="@url">here</a>.', array(
      '@url' => url('admin/config/media/file-system'),
    )), 'warning', FALSE);
    return FALSE;
  }
  $path = DRUPAL_ROOT . "/{$path}/session_cache";
  if (!file_exists($path) && !@mkdir($path)) {
    drupal_set_message(t('Session cache directory %path could not be created.', array(
      '%path' => $path,
    )), 'error', FALSE);
    return FALSE;
  }
  if (empty($bin)) {
    return $path;
  }
  if (!file_exists("{$path}/{$bin}") && !@mkdir("{$path}/{$bin}")) {
    drupal_set_message(t('Session cache subdirectory %bin could not be created inside %path', array(
      '%bin' => $bin,
      '%path' => $path,
    )), 'error', FALSE);
    return FALSE;
  }
  return "{$path}/{$bin}";
}

/**
 * Implements hook_session_cache_set().
 */
function session_cache_file_session_cache_set($method, $bin, $data) {
  if ($method != SESSION_CACHE_STORAGE_FILE) {
    return;
  }
  $path = session_cache_file_directory($bin);
  $sid = session_cache_get_sid();
  if ($data == NULL) {
    if (!$path || !$sid || !@unlink("{$path}/{$sid}")) {
      drupal_set_message(t('Session cache file for empty session state could not be deleted.', array(
        '%bin' => "{$bin}/{$sid}",
      )), 'warning', FALSE);
    }
  }
  elseif (!$path || !$sid || @file_put_contents("{$path}/{$sid}", serialize($data), FILE_EXISTS_REPLACE) === FALSE) {
    drupal_set_message(t('Session cache file for session state %bin could not be written.', array(
      '%bin' => "{$bin}/{$sid}",
    )), 'error', FALSE);
  }
}

/**
 * Implements hook_session_cache_get().
 */
function session_cache_file_session_cache_get($method, $bin) {
  if ($method != SESSION_CACHE_STORAGE_FILE) {
    return NULL;
  }
  $path = session_cache_file_directory($bin);
  $sid = session_cache_get_sid();
  $data = $path && $sid && file_exists("{$path}/{$sid}") ? unserialize(file_get_contents("{$path}/{$sid}")) : NULL;
  return $data;
}

/**
 * Implements hook_cron().
 */
function session_cache_file_cron() {
  $session_cache_root = session_cache_file_directory();
  if (empty($session_cache_root)) {
    return;
  }
  if ($bin_dirs = scandir($session_cache_root)) {
    foreach ($bin_dirs as $bin_dir) {
      if (strpos($bin_dir, '.') !== 0) {
        if ($filenames = scandir("{$session_cache_root}/{$bin_dir}")) {
          foreach ($filenames as $filename) {
            if (strpos($filename, '.') !== 0) {
              $filespec = "{$session_cache_root}/{$bin_dir}/{$filename}";
              $last_modified = filemtime($filespec);
              if ($last_modified && time() - $last_modified > SESSION_CACHE_DEFAULT_EXPIRATION_DAYS * 24 * 60 * 60) {
                if (!@unlink($filespec)) {
                  drupal_set_message(t('Could not delete expired session cache file %file.', array(
                    '%file' => $filespec,
                  )), 'warning');
                }
              }
            }
          }
        }
      }
    }
  }
}

/**
 * Implements hook_requirements().
 */
function session_cache_file_requirements($phase) {
  if ($phase != 'runtime') {
    return;
  }
  $requirements['session_cache_file']['title'] = t('Session Cache File cache');
  $session_cache_root = session_cache_file_directory();
  if ($session_cache_root) {
    $requirements['session_cache_file']['value'] = t('Installed at %path', array(
      '%path' => $session_cache_root,
    ));
    $requirements['session_cache_file']['severity'] = REQUIREMENT_OK;
  }
  else {
    $requirements['session_cache_file']['value'] = t('Not set or could not be created. Check directory permissions or re-configure <a href="@url">here</a>.', array(
      '@url' => url('admin/config/media/file-system'),
    ));
    $requirements['session_cache_file']['severity'] = REQUIREMENT_ERROR;
  }
  return $requirements;
}

Functions

Name	Description
session_cache_file_cron	Implements hook_cron().
session_cache_file_directory
session_cache_file_form_session_cache_settings_alter
session_cache_file_requirements	Implements hook_requirements().
session_cache_file_session_cache_get	Implements hook_session_cache_get().
session_cache_file_session_cache_set	Implements hook_session_cache_set().

Constants

Name	Description
SESSION_CACHE_STORAGE_FILE	@file session_cache_file.module