Adding lock_name to LockError (#3023)

* Adding lock_name to LockError

* Adding lock_name to LockError

---------

Co-authored-by: dvora-h <[email protected]>

CHANGES

@@ -1,3 +1,4 @@
+    * Add an optional lock_name attribute to LockError.
     * Fix return types for `get`, `set_path` and `strappend` in JSONCommands
     * Connection.register_connect_callback() is made public.
     * Fix async `read_response` to use `disable_decoding`.

redis/exceptions.py

@@ -81,7 +81,10 @@ class LockError(RedisError, ValueError):
     "Errors acquiring or releasing a lock"
     # NOTE: For backwards compatibility, this class derives from ValueError.
     # This was originally chosen to behave like threading.Lock.
-    pass
+
+    def __init__(self, message, lock_name=None):
+        self.message = message
+        self.lock_name = lock_name
 
 
 class LockNotOwnedError(LockError):

redis/lock.py

@@ -157,7 +157,10 @@ def register_scripts(self) -> None:
     def __enter__(self) -> "Lock":
         if self.acquire():
             return self
-        raise LockError("Unable to acquire lock within the time specified")
+        raise LockError(
+            "Unable to acquire lock within the time specified",
+            lock_name=self.name,
+        )
 
     def __exit__(
         self,
@@ -248,15 +251,18 @@ def release(self) -> None:
         """
         expected_token = self.local.token
         if expected_token is None:
-            raise LockError("Cannot release an unlocked lock")
+            raise LockError("Cannot release an unlocked lock", lock_name=self.name)
         self.local.token = None
         self.do_release(expected_token)
 
     def do_release(self, expected_token: str) -> None:
         if not bool(
             self.lua_release(keys=[self.name], args=[expected_token], client=self.redis)
         ):
-            raise LockNotOwnedError("Cannot release a lock that's no longer owned")
+            raise LockNotOwnedError(
+                "Cannot release a lock that's no longer owned",
+                lock_name=self.name,
+            )
 
     def extend(self, additional_time: int, replace_ttl: bool = False) -> bool:
         """
@@ -270,9 +276,9 @@ def extend(self, additional_time: int, replace_ttl: bool = False) -> bool:
         `additional_time`.
         """
         if self.local.token is None:
-            raise LockError("Cannot extend an unlocked lock")
+            raise LockError("Cannot extend an unlocked lock", lock_name=self.name)
         if self.timeout is None:
-            raise LockError("Cannot extend a lock with no timeout")
+            raise LockError("Cannot extend a lock with no timeout", lock_name=self.name)
         return self.do_extend(additional_time, replace_ttl)
 
     def do_extend(self, additional_time: int, replace_ttl: bool) -> bool:
@@ -284,17 +290,23 @@ def do_extend(self, additional_time: int, replace_ttl: bool) -> bool:
                 client=self.redis,
             )
         ):
-            raise LockNotOwnedError("Cannot extend a lock that's no longer owned")
+            raise LockNotOwnedError(
+                "Cannot extend a lock that's no longer owned",
+                lock_name=self.name,
+            )
         return True
 
     def reacquire(self) -> bool:
         """
         Resets a TTL of an already acquired lock back to a timeout value.
         """
         if self.local.token is None:
-            raise LockError("Cannot reacquire an unlocked lock")
+            raise LockError("Cannot reacquire an unlocked lock", lock_name=self.name)
         if self.timeout is None:
-            raise LockError("Cannot reacquire a lock with no timeout")
+            raise LockError(
+                "Cannot reacquire a lock with no timeout",
+                lock_name=self.name,
+            )
         return self.do_reacquire()
 
     def do_reacquire(self) -> bool:
@@ -304,5 +316,8 @@ def do_reacquire(self) -> bool:
                 keys=[self.name], args=[self.local.token, timeout], client=self.redis
             )
         ):
-            raise LockNotOwnedError("Cannot reacquire a lock that's no longer owned")
+            raise LockNotOwnedError(
+                "Cannot reacquire a lock that's no longer owned",
+                lock_name=self.name,
+            )
         return True

tests/test_lock.py

@@ -242,6 +242,13 @@ def test_context_manager_reacquiring_lock_no_longer_owned_raises_error(self, r):
             with self.get_lock(r, "foo", timeout=10, blocking=False):
                 r.set("foo", "a")
 
+    def test_lock_error_gives_correct_lock_name(self, r):
+        r.set("foo", "bar")
+        with pytest.raises(LockError) as excinfo:
+            with self.get_lock(r, "foo", blocking_timeout=0.1):
+                pass
+            assert excinfo.value.lock_name == "foo"
+
 
 class TestLockClassSelection:
     def test_lock_class_argument(self, r):