Issue #2856140 by kevinn, Jeremy: Call to undefined function dmemcache_object_cluster()

memcache_admin/memcache_admin.install

@@ -5,6 +5,38 @@
  * Update functions for memcache_admin.
  */
 
+/**
+ * Implements hook_requirements().
+ */
+function memcache_admin_requirements($phase) {
+  // Ensure translations don't break during installation.
+  $t = get_t();
+
+  $requirements = array();
+
+  if ($phase == 'install') {
+    if (!function_exists('dmemcache_object_cluster')) {
+      $requirements['memcache_admin'] = array(
+        'title' => $t('Memcache admin'),
+        'value' => $t('cache_backends not properly configured in settings.php, failed to load required file memcache.inc.'),
+        'description' => $t('You must properly configure cache_backends in %settings before enabling the memcache_admin module. Please review %readme for more information.', array('%settings' => 'settings.php', '%readme' => 'README.txt')),
+        'severity' => REQUIREMENT_ERROR,
+      );
+    }
+  }
+  else if ($phase == 'runtime') {
+    if (!function_exists('dmemcache_object_cluster') && module_exists('memcache_admin')) {
+      $requirements['memcache_admin'] = array(
+        'title' => $t('Memcache admin'),
+        'value' => $t('cache_backends not properly configured in settings.php, failed to load required file memcache.inc.'),
+        'description' => $t('You have enabled the memcache_admin module without properly configuring cache_backends in %settings. Please review %readme for more information.', array('%settings' => 'settings.php', '%readme' => 'README.txt')),
+        'severity' => REQUIREMENT_WARNING,
+      );
+    }
+  }
+  return $requirements;
+}
+
 /**
  * Flush caches and rebuild menu to allow new stats pages to appear.
  */

memcache_admin/memcache_admin.module

@@ -60,7 +60,7 @@ function memcache_admin_menu() {
   $memcache_servers = variable_get('memcache_servers', array('127.0.0.1:11211' => 'default'));
   $clusters = array();
   foreach ($memcache_servers as $server => $bin) {
-    if ($cluster = dmemcache_object_cluster($bin)) {
+    if (function_exists('dmemcache_object_cluster') && $cluster = dmemcache_object_cluster($bin)) {
       $name = $cluster['cluster'];
       $clusters[$name]['servers'][] = $server;
       $clusters[$name]['bin'] = _memcache_admin_get_bin_for_cluster($cluster['cluster']);