Change settings in flake8 and black.

[python_utils.git] / collect / shared_dict.py

diff --git a/collect/shared_dict.py b/collect/shared_dict.py
index 0d8e7c2f7a36aa5ddb7c54c72aecddbf56df71c3..e0a42f2c55c2fc865b0c89642d458ae26009c224 100644 (file)
--- a/collect/shared_dict.py
+++ b/collect/shared_dict.py
@@ -30,17 +30,8 @@ This class is based on https://github.com/luizalabs/shared-memory-dict
 import pickle
 from contextlib import contextmanager
 from functools import wraps
-from multiprocessing import shared_memory, RLock
-from typing import (
-    Any,
-    Dict,
-    Generator,
-    KeysView,
-    ItemsView,
-    Iterator,
-    Optional,
-    ValuesView,
-)
+from multiprocessing import RLock, shared_memory
+from typing import Any, Dict, Generator, ItemsView, Iterator, KeysView, Optional, ValuesView
 
 from decorator_utils import synchronized
 
@@ -74,6 +65,7 @@ class SharedDict(object):
         super().__init__()
         self.name = name
         self._serializer = PickleSerializer()
+        assert size_bytes is None or size_bytes > 0
         self.shared_memory = self._get_or_create_memory_block(name, size_bytes)
         self._ensure_memory_initialization()
         self.lock = RLock()
@@ -89,13 +81,11 @@ class SharedDict(object):
         try:
             return shared_memory.SharedMemory(name=name)
         except FileNotFoundError:
-            assert size_bytes
+            assert size_bytes is not None
             return shared_memory.SharedMemory(name=name, create=True, size=size_bytes)
 
     def _ensure_memory_initialization(self):
-        memory_is_empty = (
-            bytes(self.shared_memory.buf).split(SharedDict.NULL_BYTE, 1)[0] == b''
-        )
+        memory_is_empty = bytes(self.shared_memory.buf).split(SharedDict.NULL_BYTE, 1)[0] == b''
         if memory_is_empty:
             self.clear()
 
@@ -107,7 +97,8 @@ class SharedDict(object):
     def cleanup(self) -> None:
         if not hasattr(self, 'shared_memory'):
             return
-        self.shared_memory.unlink()
+        with SharedDict.MPLOCK:
+            self.shared_memory.unlink()
 
     def clear(self) -> None:
         self._save_memory({})