svid_subsite.module

<?php
// $Id$

/**
 * The subsite module is used to manage subsites that run from subdirectories
 * on the server instead of specific (sub)domains. Because FTP does not support
 * the creation of symlinks, a different approach is neccessary. This module
 * allows the creation of symlinks to the site root, which allows Drupal
 * to recognize it as a subite.
 *
 * Requirements:
 * For this module to function correctly, the user under which the server is
 * running needs write access to the directories where symlinks will be created.
 */

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

/**
 * Implementation of hook_perm().
 */
function svid_subsite_perm() {
  return array('administer subsites');
}

/**
 * Implementation of hook_menu().
 */
function svid_subsite_menu() {
  return array(
    'admin/settings/subsite' => array(
      'title' => t('Subsite administration'),
      'access arguments' => array('administer subsites'),
      'page callback' => 'drupal_get_form',
      'page arguments' => array('svid_subsite_settings_form'),
      'type' => MENU_LOCAL_TASK,
    ),
    'admin/settings/subsite/create' => array(
      'title' => t('Create'),
      'type' => MENU_DEFAULT_LOCAL_TASK,
    ),
    'admin/settings/subsite/manage' => array(
      'title' => t('Manage'),
      'access arguments' => array('administer subsites'),
      'page callback' => 'drupal_get_form',
      'page arguments' => array('svid_subsite_management_form'),
      'type' => MENU_LOCAL_TASK,
    ),
  );
}

/**
 * Form for creating a new subsite.
 */
function svid_subsite_settings_form() {
  return array(
    'subsite_path' => array(
      '#type' => 'textfield',
      '#title' => t('Path'),
      '#field_prefix' => url(NULL, array('absolute' => TRUE)),
      '#size' => '20',
      '#description' => t('The new subsite will be reachable on the given path. You will still need to create a new directory in the /sites directory for this subsite to function correctly.'),
    ),
    'subsite_submit' => array(
      '#type' => 'submit',
      '#value' => t('Add symlink'),
    ),
  );
}

/**
 * Validates the user input for creating a new subsite.
 *
 * Currenlty checks if the path supplied already exists.
 */
function svid_subsite_settings_form_validate($form, &$form_state) {
  $site_root = _svid_subsite_site_root();
  $relative_path = $form_state['values']['subsite_path'];

  $path = sprintf('%s/%s', $site_root, $relative_path);
  if (file_exists($path)) {
    form_set_error('subsite_path', t('The supplied path already exists'));
  }
  else {
    $form_state['values']['subsite_full_path'] = $path;
  }
}

/**
 * Creates the new subsite by symlinking the given path to the site root.
 */
function svid_subsite_settings_form_submit($form, &$form_state) {
  $site_root = _svid_subsite_site_root();

  if (symlink($site_root, $form_state['values']['subsite_full_path'])) {
    drupal_set_message(t('Created subsite path %path', array('%path' => $form_state['values']['subsite_path'])));
  }
  else {
    drupal_set_message(t('Failed to create subsite path %path', array('%path' => $form_state['values']['subsite_path'])));
  }
}

/**
 * Get the document root for the current Drupal installation.
 * $_SERVER['DOCUMENT_ROOT'] is not reliable across all
 * systems, so we need a way to get the correct value.
 *
 * @return (string)
 */
function _svid_subsite_site_root() {
  $absolute_dir = dirname(__FILE__);
  $relative_dir = drupal_get_path('module', 'svid_subsite');
  return substr($absolute_dir, 0, -1 * (1 + strlen($relative_dir)));
}

/**
 * Subsite management page.
 *
 * List of currently available subsites with possibility to remove them.
 */
function svid_subsite_management_form() {
  $site_root = _svid_subsite_site_root();

  $subsites = array(
    'ejw' => array(),
    'iob' => array(),
    'rsp' => array(),
  );

  $form = array();

  foreach ($subsites as $subsite => $years) {
    $subsite_root = sprintf('%s/%s', $site_root, $subsite);

    if (is_dir($subsite_root) === FALSE) {
      continue;
    }

    $dh = opendir($subsite_root);

    while (($entry = readdir($dh)) !== FALSE) {
      if ($entry == '.' || $entry == '..') {
        continue;
      }

      $subsite_root_path = sprintf('%s/%s', $subsite_root, $entry);
      $subsite_path = sprintf('%s/%s', $subsite, $entry);

      if (is_link($subsite_root_path)) {
        $paths[$subsite_path] = '';
        $form['path'][$subsite_path]['#value'] = $subsite_path;
        $form['name'][$subsite_path]['#value'] = strtoupper($subsite) . ' ' . $entry;
        $form['actions'][$subsite_path]['#value'] = l(t('view'), $subsite_path, array('absolute' => TRUE));
        $subsites[$subsite][$entry] = str_replace($site_root, '', $subsite_path);
      }
    }

    closedir($dh);
  }

  $form['delete'] = array(
    '#type' => 'checkboxes',
    '#options' => $paths
  );

  $form['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Remove selected subsites'),
  );

  return $form;
}

/**
 * Cleans up deletion array and throws an error when nothing is selected.
 */
function svid_subsite_management_form_validate($form, &$form_state) {
  $form_state['values']['delete'] = array_filter($form_state['values']['delete']);
  if (count($form_state['values']['delete']) === 0) {
    form_set_error('', t('No subsites selected.'));
  }
}

/**
 * Removes the selected subsites symlinks, rendering the subsite unreachable.
 */
function svid_subsite_management_form_submit($form, &$form_state) {
  $site_root = _svid_subsite_site_root();

  foreach ($form_state['values']['delete'] as $subsite_path) {
    $subsite_root_path = sprintf('%s/%s', $site_root, $subsite_path);
    if (unlink($subsite_root_path) === FALSE) {
      drupal_set_message(t('Failed to remove subsite %path', array('%path' => $subsite_path)), 'error');
      return;
    }
  }

  drupal_set_message(t('Succesfully removed selected subsites.'));
}

/**
 * Convert the list of subsites to a tabular structure.
 */
function theme_svid_subsite_management_form($form) {
  $header = array(
    theme('table_select_header_cell'),
    t('Name'),
    t('Path'),
    t('Actions'),
  );

  $rows = array();
  if (isset($form['path']) && is_array($form['path'])) {
    foreach (element_children($form['path']) as $subsite_path) {
      $rows[] = array(
        drupal_render($form['delete'][$subsite_path]),
        drupal_render($form['name'][$subsite_path]),
        drupal_render($form['path'][$subsite_path]),
        drupal_render($form['actions'][$subsite_path]),
      );
    }

    $content = theme('table', $header, $rows);
    $content .= drupal_render($form);
  }
  else {
    $content = t('No subsites found.');
  }

  return $content;
}

/**
 * Implementation of hook_form_alter().
 *
 * @todo This really does not belong here, but it is too small for a
 * seperate module. Find something to merge this to.
 */
function svid_subsite_form_locale_languages_configure_form_alter(&$form, &$form_state) {
  $form['language_negotiation']['#options'][4] = t('Use browser setting.');
}