Check link node

api/s6_pumps.py

@@ -67,6 +67,8 @@ def _set_pump(name: str, id: str, key: str, key_type: str, value: str, optional:
 def set_pump_node1(name: str, id: str, node1: str) -> ChangeSet:
     if not is_node(name, node1):
         return ChangeSet()
+    if get_pump_node2(name, id) == node1:
+        return ChangeSet()
 
     return _set_pump(name, id, 'node1', 'str', str(node1))
 
@@ -74,6 +76,8 @@ def set_pump_node1(name: str, id: str, node1: str) -> ChangeSet:
 def set_pump_node2(name: str, id: str, node2: str) -> ChangeSet:
     if not is_node(name, node2):
         return ChangeSet()
+    if get_pump_node1(name, id) == node2:
+        return ChangeSet()
 
     return _set_pump(name, id, 'node2', 'str', str(node2))