feat(serializer): add dill serializer support

- Add dill to SerializerName type in typing.py
- Implement dill serializer in cache.py with optional import
- Add dill to optional dependencies in pyproject.toml
- Add test_dill function in test_3rd_serializers.py
- Update README.md to document dill serializer

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: tanbro

README.md

@@ -75,7 +75,7 @@ We can see that the second call to `a_slow_func()` is served from the cache, whi
 - Simple [decorator][] syntax supporting both **`async`** and common functions, **asynchronous** and synchronous I/O.
 - Support [Redis][] **cluster**.
 - Multiple caching policies: LRU, FIFO, LFU, RR ...
-- Serialization formats: JSON, Pickle, MsgPack, YAML, BSON, CBOR ...
+- Serialization formats: JSON, Pickle, Dill, MsgPack, YAML, BSON, CBOR, cloudpickle ...
 
 ## Installation
 
@@ -462,9 +462,9 @@ def my_func_with_complex_return(x):
     return {...}  # Complex object
 ```
 
-Supported serializers: JSON, Pickle, MsgPack, YAML, BSON, CBOR, and cloudpickle.
+Supported serializers: JSON, Pickle, Dill, MsgPack, YAML, BSON, CBOR, and cloudpickle.
 
-> ⚠️ **Warning:** [`pickle`][] can execute arbitrary code during deserialization. Use with extreme caution, especially with untrusted data.
+> ⚠️ **Warning:** [`pickle`][] and `dill` can execute arbitrary code during deserialization. Use with extreme caution, especially with untrusted data.
 
 ### Handling Non-Serializable Arguments
 
@@ -1057,6 +1057,7 @@ graph LR
     LruTScriptsMixin --> lru_t_put.lua
     Serializer --> json
     Serializer --> pickle
+    Serializer --> dill
     Serializer --> msgpack
     Serializer --> bson
     Serializer --> yaml

pyproject.toml

@@ -42,6 +42,7 @@ source = "https://github.com/tanbro/redis_func_cache.git"
 [project.optional-dependencies]
 hiredis = ["redis[hiredis]"]
 pygments = ["Pygments>=2.9"]
+dill = ["dill>=0.3.6"]
 bson = ["pymongo>=3.9"]
 msgpack = ["msgpack>=1.0"]
 yaml = ["PyYAML>=5.4"]
@@ -50,6 +51,7 @@ cloudpickle = ["cloudpickle>=3.0"]
 all = [
   "redis[hiredis]",
   "Pygments>=2.9",
+  "dill>=0.3.6",
   "pymongo>=3.9",
   "msgpack>=1.0",
   "PyYAML>=5.4",

src/redis_func_cache/cache.py

@@ -17,6 +17,10 @@
 
 from redis.commands.core import AsyncScript, Script
 
+try:  # pragma: no cover
+    import dill  # type: ignore[import-not-found]
+except ImportError:  # pragma: no cover
+    dill = None  # type: ignore[assignment]
 try:  # pragma: no cover
     import bson  # type: ignore[import-not-found]
 except ImportError:  # pragma: no cover
@@ -222,6 +226,7 @@ def __init__(
 
                   - ``"json"``: Use :func:`json.dumps` and :func:`json.loads`
                   - ``"pickle"``: Use :func:`pickle.dumps` and :func:`pickle.loads`
+                  - ``"dill"``: Use :func:`dill.dumps` and :func:`dill.loads`. Only available when `dill <https://pypi.org/project/dill/>`_ is installed.
                   - ``"bson"``: Use :func:`bson.decode` and :func:`bson.encode`. Only available when `pymongo <https://pypi.org/project/pymongo/>`_ is installed.
                   - ``"msgpack"``: Use :func:`msgpack.packb` and :func:`msgpack.unpackb`. Only available when :mod:`msgpack` is installed.
                   - ``"cbor"``: Use :func:`cbor2.dumps` and :func:`cbor2.loads`. Only available when `cbor2 <https://pypi.org/project/cbor2/>`_ is installed.
@@ -301,6 +306,11 @@ def my_deserializer(data):
         "json": (lambda x: json.dumps(x).encode(), lambda x: json.loads(x)),
         "pickle": (lambda x: pickle.dumps(x), lambda x: pickle.loads(x)),
     }
+    if dill is not None:  # pragma: no cover
+        __serializers__["dill"] = (
+            lambda x: dill.dumps(x),  # pyright: ignore[reportOptionalMemberAccess]
+            lambda x: dill.loads(x),  # pyright: ignore[reportOptionalMemberAccess]
+        )
     if bson is not None:  # pragma: no cover
         __serializers__["bson"] = (
             lambda x: bson.encode({"": x}),  # pyright: ignore[reportOptionalMemberAccess]

src/redis_func_cache/typing.py

@@ -46,7 +46,7 @@
 RedisScriptT = Union[redis.commands.core.Script, redis.commands.core.AsyncScript]
 
 
-SerializerName = Literal["json", "pickle", "bson", "msgpack", "yaml", "cbor", "cloudpickle"]
+SerializerName = Literal["json", "pickle", "dill", "bson", "msgpack", "yaml", "cbor", "cloudpickle"]
 
 
 if TYPE_CHECKING:  # pragma: no cover

tests/test_3rd_serializers.py

@@ -230,3 +230,57 @@ def _test_datetime(f):
         _test_int(fn)
         _test_float(fn)
         _test_datetime(fn)
+
+
+def test_dill():
+    def _test_bytes(f):
+        for _ in range(randint(1, MAXSIZE * 2)):
+            v0 = uuid4().bytes
+            v1 = f(v0)
+            assert v0 == v1
+
+    def _test_str(f):
+        for _ in range(randint(1, MAXSIZE * 2)):
+            v0 = uuid4().hex
+            v1 = f(v0)
+            assert v0 == v1
+
+    def _test_int(f):
+        for _ in range(randint(1, MAXSIZE * 2)):
+            v0 = randint(-(2**63), 2**63 - 1)
+            v1 = f(v0)
+            assert v0 == v1
+
+    def _test_float(f):
+        for _ in range(randint(1, MAXSIZE * 2)):
+            v0 = random()
+            v1 = f(v0)
+            assert v0 == v1
+
+    def _test_bool(f):
+        for _ in range(randint(1, MAXSIZE * 2)):
+            v0 = choice((True, False))
+            v1 = f(v0)
+            assert v0 == v1
+
+    def _test_none(f):
+        for _ in range(randint(1, MAXSIZE * 2)):
+            v0 = None
+            v1 = f(v0)
+            assert v0 == v1
+
+    def _test_datetime(f):
+        for _ in range(randint(1, MAXSIZE * 2)):
+            v0 = datetime.now().replace(microsecond=0)
+            v1 = f(v0)
+            assert v0 == v1
+
+    for cache in CACHES.values():
+        fn = cache(echo, serializer="dill")
+        _test_bytes(fn)
+        _test_none(fn)
+        _test_bool(fn)
+        _test_str(fn)
+        _test_int(fn)
+        _test_float(fn)
+        _test_datetime(fn)