Guard mixing

api/s20_mixing.py

@@ -13,7 +13,9 @@ def get_mixing_schema(name: str) -> dict[str, dict[str, Any]]:
 
 
 def get_mixing(name: str, tank: str) -> dict[str, Any]:
-    m = read(name, f"select * from mixing where tank = '{tank}'")
+    m = try_read(name, f"select * from mixing where tank = '{tank}'")
+    if m == None:
+        return {}
     d = {}
     d['tank'] = str(m['tank'])
     d['model'] = str(m['model'])
@@ -61,6 +63,10 @@ def set_mixing_cmd(name: str, cs: ChangeSet) -> DbChangeSet:
 
 
 def set_mixing(name: str, cs: ChangeSet) -> ChangeSet:
+    if 'tank' not in cs.operations[0]:
+        return ChangeSet()
+    if get_mixing(name, cs.operations[0]['tank']) == {}:
+        return ChangeSet()
     return execute_command(name, set_mixing_cmd(name, cs))
 
 
@@ -77,6 +83,10 @@ def add_mixing_cmd(name: str, cs: ChangeSet) -> DbChangeSet:
 
 
 def add_mixing(name: str, cs: ChangeSet) -> ChangeSet:
+    if 'tank' not in cs.operations[0]:
+        return ChangeSet()
+    if get_mixing(name, cs.operations[0]['tank']) != {}:
+        return ChangeSet()
     return execute_command(name, add_mixing_cmd(name, cs))
 
 
@@ -93,6 +103,10 @@ def delete_mixing_cmd(name: str, cs: ChangeSet) -> DbChangeSet:
 
 
 def delete_mixing(name: str, cs: ChangeSet) -> ChangeSet:
+    if 'tank' not in cs.operations[0]:
+        return ChangeSet()
+    if get_mixing(name, cs.operations[0]['tank']) == {}:
+        return ChangeSet()
     return execute_command(name, delete_mixing_cmd(name, cs))