move persistentdict into own file, rename

chatmaild/src/chatmaild/filedict.py

@@ -0,0 +1,37 @@
+import os
+import logging
+import marshal
+import filelock
+from contextlib import contextmanager
+
+
+class FileDict:
+    """Concurrency-safe multi-reader-single-writer Persistent Dict."""
+
+    def __init__(self, path, timeout=5.0):
+        self.path = path
+        self.lock_path = path.with_name(path.name + ".lock")
+        self.timeout = timeout
+
+    @contextmanager
+    def modify(self):
+        try:
+            with filelock.FileLock(self.lock_path, timeout=self.timeout):
+                data = self.read()
+                yield data
+                write_path = self.path.with_suffix(".tmp")
+                with write_path.open("wb") as f:
+                    marshal.dump(data, f)
+                os.rename(write_path, self.path)
+        except filelock.Timeout:
+            logging.warning("could not obtain lock, removing: %r", self.lock_path)
+            os.remove(self.lock_path)
+            with self.modify() as d:
+                yield d
+
+    def read(self):
+        try:
+            with self.path.open("rb") as f:
+                return marshal.load(f)
+        except FileNotFoundError:
+            return {}

chatmaild/src/chatmaild/metadata.py

@@ -12,9 +12,8 @@ import sys
 import logging
 import os
 import requests
-import marshal
-from contextlib import contextmanager
-import filelock
+
+from .filedict import FileDict
 
 
 DICTPROXY_LOOKUP_CHAR = "L"
@@ -27,38 +26,6 @@ DICTPROXY_TRANSACTION_CHARS = "SBC"
 METADATA_TOKEN_KEY = "devicetoken"
 
 
-class PersistentDict:
-    """Concurrency-safe multi-reader-single-writer Persistent Dict."""
-
-    def __init__(self, path, timeout=5.0):
-        self.path = path
-        self.lock_path = path.with_name(path.name + ".lock")
-        self.timeout = timeout
-
-    @contextmanager
-    def modify(self):
-        try:
-            with filelock.FileLock(self.lock_path, timeout=self.timeout):
-                data = self.get()
-                yield data
-                write_path = self.path.with_suffix(".tmp")
-                with write_path.open("wb") as f:
-                    marshal.dump(data, f)
-                os.rename(write_path, self.path)
-        except filelock.Timeout:
-            logging.warning("could not obtain lock, removing: %r", self.lock_path)
-            os.remove(self.lock_path)
-            with self.modify() as d:
-                yield d
-
-    def get(self):
-        try:
-            with self.path.open("rb") as f:
-                return marshal.load(f)
-        except FileNotFoundError:
-            return {}
-
-
 class Notifier:
     def __init__(self, vmail_dir):
         self.vmail_dir = vmail_dir
@@ -68,7 +35,7 @@ class Notifier:
         mbox_path = self.vmail_dir.joinpath(mbox)
         if not mbox_path.exists():
             mbox_path.mkdir()
-        return PersistentDict(mbox_path / "metadata.marshalled")
+        return FileDict(mbox_path / "metadata.marshalled")
 
     def add_token(self, mbox, token):
         with self.get_metadata_dict(mbox).modify() as data:
@@ -78,7 +45,7 @@ class Notifier:
             if token not in tokens:
                 tokens.append(token)
 
-    def del_token(self, mbox, token):
+    def remove_token(self, mbox, token):
         with self.get_metadata_dict(mbox).modify() as data:
             tokens = data.get(METADATA_TOKEN_KEY)
             if tokens:
@@ -88,7 +55,7 @@ class Notifier:
                     pass
 
     def get_tokens(self, mbox):
-        return self.get_metadata_dict(mbox).get().get(METADATA_TOKEN_KEY, [])
+        return self.get_metadata_dict(mbox).read().get(METADATA_TOKEN_KEY, [])
 
     def new_message_for_mbox(self, mbox):
         self.to_notify_queue.put(mbox)
@@ -109,7 +76,7 @@ class Notifier:
             if response.status_code == 410:
                 # 410 Gone status code
                 # means the token is no longer valid.
-                self.del_token(mbox, token)
+                self.remove_token(mbox, token)
 
 
 def handle_dovecot_protocol(rfile, wfile, notifier):

chatmaild/src/chatmaild/tests/test_filedict.py

@@ -0,0 +1,24 @@
+from chatmaild.filedict import FileDict
+
+
+def test_basic(tmp_path):
+    fdict = FileDict(tmp_path.joinpath("metadata"))
+    assert fdict.read() == {}
+    with fdict.modify() as d:
+        d["devicetoken"] = [1, 2, 3]
+        d["456"] = 4.2
+    new = fdict.read()
+    assert new["devicetoken"] == [1, 2, 3]
+    assert new["456"] == 4.2
+
+
+def test_dying_lock(tmp_path, caplog):
+    fdict1 = FileDict(tmp_path.joinpath("metadata"))
+    fdict2 = FileDict(tmp_path.joinpath("metadata"), timeout=0.1)
+    with fdict1.modify() as d:
+        with fdict2.modify() as d2:
+            d2["1"] = "2"
+        assert "could not obtain" in caplog.records[0].msg
+        d["1"] = "3"
+    assert fdict1.read()["1"] == "3"
+    assert fdict2.read()["1"] == "3"

chatmaild/src/chatmaild/tests/test_metadata.py

@@ -5,7 +5,6 @@ from chatmaild.metadata import (
     handle_dovecot_request,
     handle_dovecot_protocol,
     Notifier,
-    PersistentDict,
 )
 
 
@@ -30,12 +29,12 @@ def test_notifier_persistence(tmp_path):
     notifier1.add_token("user3@example.org", "456")
     assert notifier2.get_tokens("user1@example.org") == ["01234"]
     assert notifier2.get_tokens("user3@example.org") == ["456"]
-    notifier2.del_token("user1@example.org", "01234")
+    notifier2.remove_token("user1@example.org", "01234")
     assert not notifier1.get_tokens("user1@example.org")
 
 
 def test_notifier_delete_without_set(notifier):
-    notifier.del_token("user@example.org", "123")
+    notifier.remove_token("user@example.org", "123")
     assert not notifier.get_tokens("user@example.org")
 
 
@@ -217,28 +216,3 @@ def test_notifier_thread_run_gone_removes_token(notifier):
     url, data, timeout = requests[1]
     assert data == "45678"
     assert notifier.get_tokens("user@example.org") == ["45678"]
-
-
-class TestPersistentDict:
-    @pytest.fixture
-    def store(self, tmp_path):
-        return PersistentDict(tmp_path.joinpath("metadata"))
-
-    def test_basic(self, store):
-        assert store.get() == {}
-        with store.modify() as d:
-            d["devicetoken"] = [1, 2, 3]
-            d["456"] = 4.2
-        new = store.get()
-        assert new["devicetoken"] == [1, 2, 3]
-        assert new["456"] == 4.2
-
-    def test_dying_lock(self, tmp_path, caplog):
-        store1 = PersistentDict(tmp_path.joinpath("metadata"))
-        store2 = PersistentDict(tmp_path.joinpath("metadata"), timeout=0.1)
-        with store1.modify() as d:
-            with store2.modify() as d2:
-                d2["1"] = "2"
-            assert "could not obtain" in caplog.records[0].msg
-            d["1"] = "3"
-        assert store1.get()["1"] == "3"