hosting.features.inc

<?php
/**
 * @file
 * Include for functionality related to Hosting module features.
 */

/**
 * This hosting feature is disabled.
 */
define('HOSTING_FEATURE_DISABLED', 0);

/**
 * This hosting feature is enabled.
 */
define('HOSTING_FEATURE_ENABLED', 1);

/**
 * This hosting feature is required.
 */
define('HOSTING_FEATURE_REQUIRED', 2);


/**
 * Determine whether a specific feature of the hosting system is turned on.
 *
 * @param string $feature
 *   The feature to check the status of, e.g. "client" or "platform".
 *
 * @return bool
 *   TRUE if the feature is enabled, FALSE if it is disabled.
 */
function hosting_feature($feature) {
  static $features = array();

  if (!count($features)) {
    $features = hosting_get_features();
  }
  if (isset($features[$feature]['status']) && ($features[$feature]['status'] == HOSTING_FEATURE_REQUIRED)) {
    $return = module_exists($features[$feature]['module']) ? HOSTING_FEATURE_REQUIRED : HOSTING_FEATURE_DISABLED;
  }
  elseif (isset($features[$feature]['module'])) {
    $return = (module_exists($features[$feature]['module'])) ? HOSTING_FEATURE_ENABLED : HOSTING_FEATURE_DISABLED;
  }
  else {
    $return = variable_get('hosting_feature_' . $feature, !empty($features[$feature]['status']));
  }
  return $return;
}

/**
 * The Hosting features form.
 *
 * This returns a form with any known Hosting features grouped and listed. It
 * allows administrators to enable or disable the features.
 *
 * @param array $form
 *   The built form.
 * @param array $form_state
 *   The current form state.
 *
 * @return array
 *   A drupal form.
 *
 * @see hosting_features_form_submit()
 */
function hosting_features_form($form, &$form_state) {
  $form = array();
  $form['settings'] = array(
    '#type' => 'checkboxes',
    '#title' => 'Settings',
    '#options' => array('dependencies' => 'Display dependencies', 'roles' => 'Display roles and permissions'),
    '#default_value' => variable_get('hosting_features_form_settings', array()),
    '#weight' => -20,
  );

  $optional = array(
    '#type' => 'fieldset',
    '#title' => t('Optional system features'),
    '#description' => t('You may choose any of the additional system features from the list below.'),
    '#collapsible' => FALSE,
  );

  $required = array(
    '#type' => 'fieldset',
    '#title' => t('Required system features'),
    '#collapsed' => TRUE,
    '#collapsible' => TRUE,
    '#weight' => -10,
    '#description' => t("These features are central to Aegir's functionality, and thus cannot be disabled."),
  );

  $experimental = array(
    '#type' => 'fieldset',
    '#title' => t('Experimental'),
    '#collapsed' => TRUE,
    '#collapsible' => TRUE,
    '#description' => t('Features marked experimental have not been completed to a satisfactory level to be considered production ready, so use at your own risk.'),
  );

  $advanced = array(
    '#type' => 'fieldset',
    '#title' => t('Advanced'),
    '#collapsed' => TRUE,
    '#collapsible' => TRUE,
    '#description' => t('Advanced features require a deep knowledge of Aegir and Drupal to be considered safe, so use at your own risk.'),
  );

  $features = hosting_get_features(TRUE);
  foreach ($features as $feature => $info) {
    $description = $info['description'];

    if ($settings = variable_get('hosting_features_form_settings', FALSE)) {
      if ($settings['dependencies']) {
        // Gather dependencies and their statuses.
        $depends_on = isset($info['dependencies']['features']) ? $info['dependencies']['features'] : FALSE;
        if (is_array($depends_on)) {
          $description .= theme('hosting_feature_dependencies', array(
            'dependencies' => $depends_on,
            'prefix' => 'Depends on',
            'features' => $features));
        }

        // Gather relying features and their statuses.
        $required_by = isset($info['dependencies']['reverse']) ? $info['dependencies']['reverse'] : FALSE;
        if (is_array($required_by)) {
          $description .= theme('hosting_feature_dependencies', array(
            'dependencies' => $required_by,
            'prefix' => 'Required by',
            'features' => $features));
        }
      }
    }

    if ($settings = variable_get('hosting_features_form_settings', FALSE)) {
      if ($settings['roles']) {
        // Add collapsed fieldset listing the feature's permissions assigned per role.
        $role_perms = isset($info['role_permissions']) ? $info['role_permissions'] : FALSE;
        if (is_array($role_perms)) {
          $element = drupal_get_form('hosting_feature_role_perms_table', $role_perms);
          $description .= drupal_render_children($element);
        }
      }
    }

    // Disable checkbox for required features.
    $locked = FALSE;
    if ($info['status'] == HOSTING_FEATURE_REQUIRED) {
      $locked = TRUE;
    }
    elseif (isset($required_by) && $required_by) {
      foreach ($required_by as $mod => $feat) {
        $locked = $features[$feat]['enabled'] ? TRUE : $locked;
      }
    }

    $element = array(
      '#type' => 'checkbox',
      '#title' => check_plain($info['title']),
      '#description' => $description,
      '#default_value' => $info['status'] == HOSTING_FEATURE_REQUIRED ? 1 : hosting_feature($feature),
      '#required' => hosting_feature($feature) == HOSTING_FEATURE_REQUIRED,
      '#disabled' => $locked,
    );

    // Add another fieldset based on contrib module package.
    $package = FALSE;
    if ($info['package'] != 'Hosting') {
      $package = array(
        '#type' => 'fieldset',
        '#title' => $info['package'],
        '#collapsed' => FALSE,
        '#collapsible' => TRUE,
      );
    }
    if ($package) {
      if ($info['group'] == 'required') {
        if (!isset($required[$info['package']])) {
          $required[$info['package']] = $package;
        }
        $required[$info['package']]['hosting_feature_' . $feature] = $element;
      }
      elseif ($info['group'] == 'optional') {
        if (!isset($optional[$info['package']])) {
          $optional[$info['package']] = $package;
        }
        $optional[$info['package']]['hosting_feature_' . $feature] = $element;
      }
      elseif ($info['group'] == 'advanced') {
        if (!isset($advanced[$info['package']])) {
          $advanced[$info['package']] = $package;
        }
        $advanced[$info['package']]['hosting_feature_' . $feature] = $element;
      }
      else {
        if (!isset($experimental[$info['package']])) {
          $experimental[$info['package']] = $package;
        }
        $experimental[$info['package']]['hosting_feature_' . $feature] = $element;
      }
    }
    // This feature is in the 'Hosting' module package.
    else {
      if (isset($info['group']) && $info['group'] == 'required') {
        $required['hosting_feature_' . $feature] = $element;
      }
      elseif (isset($info['group']) && $info['group'] == 'optional') {
        $optional['hosting_feature_' . $feature] = $element;
      }
      elseif (isset($info['group']) && $info['group'] == 'advanced') {
        $advanced['hosting_feature_' . $feature] = $element;
      }
      else {
        $experimental['hosting_feature_' . $feature] = $element;
      }
    }

  }
  $form['required'] = $required;
  $form['optional'] = $optional;
  $form['advanced'] = $advanced;
  $form['experimental'] = $experimental;
  $form['#submit'][] = 'hosting_features_form_submit';
  return system_settings_form($form);
}

/**
 * Submit callback for the Hosting features form.
 *
 * We process the submitted values and enable any features that the user has
 * requested. This may involve enabling a module and their dependencies and/or
 * calling a specified callback function.
 *
 * @param array $form
 *   The built form.
 * @param array $form_state
 *   The current form state.
 *
 * @see hosting_features_form()
 * @see hook_hosting_feature()
 */
function hosting_features_form_submit($form, &$form_state) {
  variable_set('hosting_features_form_settings', $form_state['values']['settings']);

  // Get form values, filtering out irrelevant entries.
  $values = array_filter($form_state['values'], 'is_int');

  // Figure out which features to enable and/or disable.
  $features = hosting_determine_features_status($values);

  // Enable the feature(s).
  $rebuild_on_enable = count($features['disable']) ? FALSE : TRUE;
  hosting_features_enable($features['enable'], $rebuild_on_enable);

  // Disable the feature(s).
  hosting_features_disable($features['disable']);
}

/**
 * Get a listing of all known Hosting features.
 *
 * @param bool $refresh
 *   (optional) Pass in TRUE to force the list of features to be rebuilt and not
 *   returned from the cache.
 *
 * @return array
 *   An array of Hosting features.
 *
 * @see hook_hosting_feature()
 */
function hosting_get_features($refresh = FALSE) {
  $cache = cache_get('hosting_features');

  if (empty($cache->data) || $refresh) {
    // Include any optional hosting.feature.*.inc files.
    $files = drupal_system_listing("/hosting\.feature\.[a-zA-Z0-9_]*\.inc$/", "modules");
    if (count($files)) {
      foreach ($files as $name => $info) {
        include_once DRUPAL_ROOT . '/' . $info->uri;
      }
    }
    // We need the equivalent of module_invoke_all('hosting_feature'), but
    // including disabled features/modules too.
    $functions = get_defined_functions();
    foreach ($functions['user'] as $function) {
      if (preg_match('/_hosting_feature$/', $function)) {
        $hooks[] = $function;
      }
    }
    $features = array();
    foreach ($hooks as $func) {
      $features = array_merge($features, $func());
    }

    // Add module dependencies, package and enabled status.
    $module_cache = system_rebuild_module_data();
    $modules = array();
    foreach ($features as $feature => $info) {
      if (isset($module_cache[$info['module']]->info['required']) && $module_cache[$info['module']]->info['required']) {
        $features[$feature]['status'] = HOSTING_FEATURE_REQUIRED;
      }
      $features[$feature]['enabled'] = $module_cache[$info['module']]->status;
      $features[$feature]['package'] = $module_cache[$info['module']]->info['package'];
      $features[$feature]['dependencies']['modules'] = $module_cache[$info['module']]->info['dependencies'];
      // Generate a list of features keyed by module name.
      $modules[$info['module']] = $feature;
    }

    // Add Hosting feature dependencies, keyed by module.
    foreach ($features as $feature => $info) {
      foreach ($info['dependencies']['modules'] as $dependency) {
        if (array_key_exists($dependency, $modules) && array_key_exists($modules[$dependency], $features)) {
          $features[$feature]['dependencies']['features'][$dependency] = $modules[$dependency];
          $features[$modules[$dependency]]['dependencies']['reverse'][$info['module']] = $feature;
        }
      }
    }

    cache_set('hosting_features', $features);
    return $features;
  }
  else {
    return $cache->data;
  }
}

/**
 * Determine which node types are provided by Hosting features.
 *
 * @param bool $refresh
 *   (optional) Pass in TRUE to force the list of node types to be rebuilt and
 *   not returned from the cache.
 *
 * @return true
 *   An array of node types keyed by the Hosting feature that provides them.
 */
function hosting_feature_node_types($refresh = FALSE) {
  static $types;

  if (!is_array($types) || $refresh) {
    $features = hosting_get_features($refresh);
    foreach ($features as $feature => $info) {
      if (!empty($info['node'])) {
        $types[$feature] = $info['node'];
      }
    }
  }
  return $types;
}

/**
 * Theme function to display Hosting feature dependencies.
 */
function theme_hosting_feature_dependencies($vars) {
  $return = "<div class=\"admin-required\">{$vars['prefix']}:";
  $last = end($vars['dependencies']);
  reset($vars['dependencies']);
  foreach ($vars['dependencies'] as $module => $require) {
    $return .= ' ' . $vars['features'][$require]['title'];
    $enabled = $vars['features'][$require]['enabled'] ? 'enabled' : 'disabled';
    $return .= " (<span class=\"admin-$enabled\">";
    $return .= $enabled;
    $return .= '</span>)';
    $return .= $require == $last ? '.</div>' : ',';
  }
  return $return;
}

/**
 * Helper function to list Hosting feature permissions.
 */
function hosting_feature_role_perms_table($form, &$form_table, $role_perms) {
  $form = array();
  $form['role_perms'] = array(
    '#type' => 'fieldset',
    '#title' => 'Roles & permissions',
    '#description' => 'Upon enabling this feature, the following roles will be assigned the listed permissions.',
    '#collapsible' => TRUE,
    '#collapsed' => TRUE,
  );
  $table = '<table><thead><tr><th>Role</th><th>Permissions</th></tr></thead><tbody>';
  foreach ($role_perms as $role => $perms) {
    $table .= '<tr><td>' . $role . '</td>';
    $table .= '<td>' . implode(', ', $perms) . '</td></tr>';
  }
  $table .= '</tbody></table>';
  $form['role_perms']['table'] = array(
    '#markup' => $table,
  );
  return $form;
}


/**
 * Enable one or more Hosting features.
 *
 * @param bool $rebuild
 *   Rebuild caches afterwards, default TRUE.
 * @param bool $enable
 *   Also enable the Drupal module, default TRUE.
 */
function hosting_features_enable($features, $rebuild = TRUE, $enable = TRUE) {
  if (count($features)) {

    include_once 'includes/install.inc';

    $all_features = hosting_get_features();
    $titles = array();
    foreach ($features as $feature) {
      $titles[] = $all_features[$feature]['title'];
    }
    drupal_set_message(t("Enabling %feature feature!plural.", array(
      '%feature' => implode(", ", $titles),
      '!plural' => count($features) > 1 ? 's' : '',
    )));

    foreach ($features as $module => $feature) {
      variable_set('hosting_feature_' . $feature, HOSTING_FEATURE_ENABLED);
      if ($enable) {
        $success = module_enable(array($module));
        if (!$success) {
          variable_set('hosting_feature_' . $feature, HOSTING_FEATURE_DISABLED);
          $module_data = system_rebuild_module_data();
          $missing = array_keys(array_diff_key($module_data[$module]->requires, $module_data));
          drupal_set_message(t("An error occurred enabling the `:feature` feature. Missing dependencies: :missing.", array(':feature' => $feature, ':missing' => implode(', ', $missing))), 'error');
        }
      }
      if (isset($all_features[$feature]['enable']) && function_exists($callback = $all_features[$feature]['enable'])) {
        $callback();
      }
      $role_perms = isset($all_features[$feature]['role_permissions']) ? $all_features[$feature]['role_permissions'] : array();

      hosting_add_permissions($module, $role_perms);
    }

    if ($rebuild) {
      hosting_feature_rebuild_caches($features);
    }
  }

}

/**
 * Disable one or more Hosting features.
 *
 * @param bool $rebuild
 *   Rebuild caches afterwards, default TRUE.
 * @param bool $disable_module
 *   Also disable the Drupal module, default TRUE.
 */
function hosting_features_disable($disable, $rebuild = TRUE, $disable_module = TRUE) {
  if (count($disable)) {
    drupal_set_message(t("Disabling %feature feature!plural.", array(
      '%feature' => implode(", ", $disable),
      '!plural' => count($disable) > 1 ? 's' : '',
    )));
    include_once 'includes/install.inc';
    if ($disable_module) {
      module_disable(array_keys($disable));
    }
    $features = hosting_get_features();
    foreach ($disable as $module => $feature) {
      if (isset($features[$feature]['disable']) && function_exists($callback = $features[$feature]['disable'])) {
        $callback();
      }
      variable_set('hosting_feature_' . $feature, HOSTING_FEATURE_DISABLED);
    }
    if ($rebuild) {
      hosting_feature_rebuild_caches();
    }
  }

}

/**
 * Determine the status and actions to take on Hosting features.
 *
 * Given an array of Hosting features and their desired statuses, determine
 * which are enabled, which should be, and which should be disabled.
 */
function hosting_determine_features_status($values) {
  $features = hosting_get_features();
  // List of features currently enabled.
  $enabled = array();
  // List of features to enable.
  $enable = array();
  // List of features to disable.
  $disable = array();

  foreach ($features as $feature => $info) {
    $value = $values['hosting_feature_' . $feature];
    $current = $info['enabled'];
    if ($current) {
      $enabled[$features[$feature]['module']] = $features[$feature]['title'];
      if (!$value) {
        $disable[$features[$feature]['module']] = $features[$feature]['title'];
      }
    }
    elseif ($value) {
      $enable[$features[$feature]['module']] = $feature;
      // Add dependencies to enable.
      if (isset($info['dependencies']['features']) && count($info['dependencies']['features'])) {
        foreach ($info['dependencies']['features'] as $module_dep => $feature_dep) {
          $enable[$module_dep] = $feature_dep;
        }
      }
    }
  }

  // Remove any features we're about to enable from those to disable.
  $disable = array_diff_assoc($disable, $enable);
  // Remove any features already enabled from those to enable.
  $enable = array_diff_assoc($enable, $enabled);

  return array(
    'enabled' => $enabled,
    'enable' => $enable,
    'disable' => $disable,
  );
}

/**
 * Perform necessary task after enabling or disabling Hosting features.
 */
function hosting_feature_rebuild_caches($features = array()) {
  // Rebuild schema.
  drupal_get_schema(NULL, TRUE);

  // Rebuild menu.
  menu_rebuild();

  // Record enabled features in the Hosting features registry (in
  // /var/aegir/.drush/drushrc.php)

  // Allow scripts to skip automatic verify tasks by passing '--no-verify'
  if (function_exists('drush_get_option') &&
      drush_get_option('no-verify', FALSE)) {
    return;
  }
  if ($nid = hosting_get_hostmaster_site_nid()) {
    hosting_add_task($nid, 'verify');
  }
}

/**
 * Add a Hosting Feature's permissions to the appropriate roles.
 *
 * @param string $module
 *   The name of the Hosting Feature module whose permissions we're adding.
 * @param array $role_perms
 *   An array of arrays keyed by the role name. The values are the permissions
 *   to enable.
 */
function hosting_add_permissions($module, $role_perms) {
  // Make sure permissions exist before adding them, since we might want to add
  // permissions from optional modules.
  $permissions = user_permission_get_modules();
  foreach ($role_perms as $role => $perms) {
    foreach ($perms as $i => $permission) {
      if (!isset($permissions[$permission])) {
        unset($role_perms[$role][$i]);
      }
    }
  }

  // The Aegir admin role automatically gets all permissions from any hosting module.
  if (function_exists($module . '_permission')) {
    $perms = module_invoke($module, 'permission');
    foreach (array_keys($perms) as $perm) {
      $role_perms['aegir administrator'][] = $perm;
    }
  }

  foreach (user_roles() as $rid => $name) {
    if (array_key_exists($name, $role_perms)) {
      user_role_grant_permissions($rid, $role_perms[$name]);
      drupal_set_message(t("The '%role' role was assigned the following permission!plural: '%perms'.", array(
        '%role' => $name,
        '%perms' => implode('\', \'', $role_perms[$name]),
        '!plural' => count($role_perms[$name]) > 1 ? 's' : '',
      )));
    }
  }
}