Implement clustering housekeeping, deleting 'dead' nodes

apps/clustering/tasks.py

@@ -4,14 +4,22 @@ import logging
 
 from lock_manager.decorators import simple_locking
 
-from .models import Node
+from .models import Node, ClusteringConfig
 
 LOCK_EXPIRE = 10
 
 logger = logging.getLogger(__name__)
 
 
-@simple_locking('refresh_node', 10)
-def refresh_node():
+@simple_locking('node_heartbeat', 10)
+def node_heartbeat():
     logger.debug('starting')
-    node = Node.objects.myself()  # Automatically calls the refresh() method too
+    node = Node.objects.myself()
+    node.save()
+
+
+@simple_locking('house_keeping', 10)
+def house_keeping():
+    logger.debug('starting')
+    ClusteringConfig.objects.delete_dead_nodes()
+