function bat_entity_access_query_alter in Booking and Availability Management Tools for Drupal 7

Same name and namespace in other branches

1. 8 bat.module \bat_entity_access_query_alter()

Implements hook_query_alter().

Enforces access control for bat units during database queries.

3 calls to bat_entity_access_query_alter()

bat_event_query_bat_event_access_alter in modules/bat_event/bat_event.module

Implements hook_query_TAG_alter().

bat_unit_query_bat_type_access_alter in modules/bat_unit/bat_unit.module

Implements hook_query_TAG_alter().

bat_unit_query_bat_unit_access_alter in modules/bat_unit/bat_unit.module

Implements hook_query_TAG_alter().

File

./bat.module, line 371

Provides basic underlying functionality and configuration options used by all BAT modules.

Code

function bat_entity_access_query_alter($query, $entity_type, $base_table = NULL, $account = NULL, $op = 'view') {
  global $user;

  // Get the Drupal user account from the query if available, or
  // default to the logged in user if not.
  if (!isset($account) && !($account = $query
    ->getMetaData('account'))) {
    $account = $user;
  }

  // Do not apply any conditions for users with administrative view permissions.
  if (user_access('bypass ' . $entity_type . ' access', $account) || user_access($op . ' any ' . $entity_type . ' entity', $account)) {
    return;
  }

  // Get the entity type info array for the current access check and prepare a
  // conditions object.
  $entity_info = entity_get_info($entity_type);

  // If a base table wasn't specified, attempt to read it from the query if
  // available, look for a table in the query's tables array that matches the
  // base table of the given entity type, or just default to the first table.
  if (!isset($base_table) && !($base_table = $query
    ->getMetaData('base_table'))) {

    // Initialize the base table to the first table in the array. If a table can
    // not be found that matches the entity type's base table, this will result
    // in an invalid query if the first table is not the table we expect,
    // forcing the caller to actually properly pass a base table in that case.
    $tables = $query
      ->getTables();
    reset($tables);
    $base_table = key($tables);
    foreach ($tables as $table_info) {
      if (!$table_info instanceof SelectQueryInterface) {

        // If this table matches the entity type's base table, use its table
        // alias as the base table for the purposes of bundle and ownership
        // access checks.
        if ($table_info['table'] == $entity_info['base table']) {
          $base_table = $table_info['alias'];
        }
      }
    }
  }

  // Prepare an OR container for conditions. Conditions will be added that seek
  // to grant access, meaning any particular type of permission check may grant
  // access even if none of the others apply. At the end of this function, if no
  // conditions have been added to the array, a condition will be added that
  // always returns FALSE (1 = 0).
  $conditions = db_or();

  // Loop over every possible bundle for the given entity type.
  foreach ($entity_info['bundles'] as $bundle_name => $bundle_info) {

    // If the user has access to operation entities of the current bundle...
    if (user_access($op . ' any ' . $entity_type . ' entity of bundle ' . $bundle_name, $account)) {

      // Add a condition granting access if the entity specified by the view
      // query is of the same bundle.
      $conditions
        ->condition($base_table . '.' . $entity_info['entity keys']['bundle'], $bundle_name);
    }
    elseif ($account->uid && !empty($entity_info['access arguments']['user key']) && user_access($op . ' own ' . $entity_type . ' entities of bundle ' . $bundle_name, $account)) {

      // Add an AND condition group that grants access if the entity specified
      // by the view query matches the same bundle and belongs to the user.
      $conditions
        ->condition(db_and()
        ->condition($base_table . '.' . $entity_info['entity keys']['bundle'], $bundle_name)
        ->condition($base_table . '.' . $entity_info['access arguments']['user key'], $account->uid));
    }
  }

  // If the given entity type has a user ownership key...
  if (!empty($entity_info['access arguments']['user key'])) {

    // Perform 'operation own' access control for the entity in the query if the
    // user is authenticated.
    if ($account->uid && user_access($op . ' own ' . $entity_type . ' entities', $account)) {
      $conditions
        ->condition($base_table . '.' . $entity_info['access arguments']['user key'], $account->uid);
    }
  }

  // Prepare an array of condition alter hooks to invoke and an array of context
  // data for the current query.
  $hooks = array(
    'bat_entity_access_' . $op . '_condition_' . $entity_type,
    'bat_entity_access_' . $op . '_condition',
  );
  $context = array(
    'account' => $account,
    'entity_type' => $entity_type,
    'base_table' => $base_table,
  );

  // Allow other modules to add conditions to the array as necessary.
  drupal_alter($hooks, $conditions, $context);

  // If we have more than one condition based on the entity access permissions
  // and any hook implementations...
  if (count($conditions)) {

    // Add the conditions to the query.
    $query
      ->condition($conditions);
  }
  else {

    // Otherwise, since we don't have any possible conditions to match against,
    // we falsify this query. View checks are access grants, not access denials.
    $query
      ->where('1 = 0');
  }
}