Fixes #4789: group_gatekeeper() and river hide closed/invisible group content more reliably

1 files changed, 93 insertions, 0 deletions

diff --git a/engine/classes/ElggGroupItemVisibility.php b/engine/classes/ElggGroupItemVisibility.php
new file mode 100644
index 000000000..2c7e2abb4
--- /dev/null
+++ b/engine/classes/ElggGroupItemVisibility.php
@@ -0,0 +1,93 @@
+<?php
+
+/**
+ * Determines if otherwise visible items should be hidden from a user due to group
+ * policy or visibility.
+ *
+ * @class      ElggGroupItemVisibility
+ * @package    Elgg.Core
+ * @subpackage Groups
+ *
+ * @access private
+ */
+class ElggGroupItemVisibility {
+
+	const REASON_MEMBERSHIP = 'membershiprequired';
+	const REASON_LOGGEDOUT = 'loggedinrequired';
+	const REASON_NOACCESS = 'noaccess';
+
+	/**
+	 * @var bool
+	 */
+	public $shouldHideItems = false;
+
+	/**
+	 * @var string
+	 */
+	public $reasonHidden = '';
+
+	/**
+	 * Determine visibility of items within a container for the current user
+	 *
+	 * @param int $container_guid GUID of a container (may/may not be a group)
+	 *
+	 * @return ElggGroupItemVisibility
+	 *
+	 * @todo Make this faster, considering it must run for every river item.
+	 */
+	static public function factory($container_guid) {
+		// cache because this may be called repeatedly during river display, and
+		// due to need to check group visibility, cache will be disabled for some
+		// get_entity() calls
+		static $cache = array();
+
+		$ret = new ElggGroupItemVisibility();
+
+		if (!$container_guid) {
+			return $ret;
+		}
+
+		$user = elgg_get_logged_in_user_entity();
+		$user_guid = $user ? $user->guid : 0;
+
+		$container_guid = (int) $container_guid;
+
+		$cache_key = "$container_guid|$user_guid";
+		if (empty($cache[$cache_key])) {
+			// compute
+
+			$container = get_entity($container_guid);
+			$is_visible = (bool) $container;
+
+			if (!$is_visible) {
+				// see if it *really* exists...
+				$prev_access = elgg_set_ignore_access();
+				$container = get_entity($container_guid);
+				elgg_set_ignore_access($prev_access);
+			}
+
+			if ($container && $container instanceof ElggGroup) {
+				/* @var ElggGroup $container */
+
+				if ($is_visible) {
+					if (!$container->isPublicMembership()) {
+						if ($user) {
+							if (!$container->isMember($user) && !$user->isAdmin()) {
+								$ret->shouldHideItems = true;
+								$ret->reasonHidden = self::REASON_MEMBERSHIP;
+							}
+						} else {
+							$ret->shouldHideItems = true;
+							$ret->reasonHidden = self::REASON_LOGGEDOUT;
+						}
+					}
+				} else {
+					$ret->shouldHideItems = true;
+					$ret->reasonHidden = self::REASON_NOACCESS;
+				}
+			}
+			$cache[$cache_key] = $ret;
+		}
+		return $cache[$cache_key];
+	}
+}