Merge pull request #133 from mjpieters/correct_json_decode_return

Clean up type annotations

.github/workflows/ci.yml

@@ -2,12 +2,17 @@ name: ci
 on: [ push, pull_request ]
 jobs:
   ci:
+    strategy:
+      matrix:
+        python: ["3.7", "3.8", "3.9", "3.10", "3.11"]
+    
+    name: "Test on Python ${{ matrix.python }}"
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
       - uses: actions/setup-python@v4
         with:
-          python-version: "3.x"
+          python-version: "${{ matrix.python }}"
       - name: Install and configure Poetry
         run: |
           pip install -U pip poetry

Makefile

@@ -14,6 +14,8 @@ style: deps
 check: deps
 	@black $(checkfiles) || (echo "Please run 'make style' to auto-fix style issues" && false)
 	@flake8 $(checkfiles)
+	@mypy ${checkfiles}
+	@pyright ${checkfiles}
 
 test: deps
 	$(py_warn) pytest

examples/in_memory/main.py

@@ -1,3 +1,6 @@
+# pyright: reportGeneralTypeIssues=false
+from typing import Dict, Optional
+
 import pendulum
 import uvicorn
 from fastapi import FastAPI
@@ -84,9 +87,9 @@ app.get("/method")(cache(namespace="test")(instance.handler_method))
 # cache a Pydantic model instance; the return type annotation is required in this case
 class Item(BaseModel):
     name: str
-    description: str | None = None
+    description: Optional[str] = None
     price: float
-    tax: float | None = None
+    tax: Optional[float] = None
 
 
 @app.get("/pydantic_instance")
@@ -110,7 +113,7 @@ async def uncached_put():
 @cache(namespace="test", expire=5, injected_dependency_namespace="monty_python")
 def namespaced_injection(
     __fastapi_cache_request: int = 42, __fastapi_cache_response: int = 17
-) -> dict[str, int]:
+) -> Dict[str, int]:
     return {
         "__fastapi_cache_request": __fastapi_cache_request,
         "__fastapi_cache_response": __fastapi_cache_response,
@@ -123,4 +126,4 @@ async def startup():
 
 
 if __name__ == "__main__":
-    uvicorn.run("main:app", debug=True, reload=True)
+    uvicorn.run("main:app", reload=True)

examples/redis/main.py

@@ -1,3 +1,4 @@
+# pyright: reportGeneralTypeIssues=false
 import time
 
 import pendulum
@@ -87,4 +88,4 @@ async def startup():
 
 
 if __name__ == "__main__":
-    uvicorn.run("main:app", debug=True, reload=True)
+    uvicorn.run("main:app", reload=True)

fastapi_cache/backends/dynamodb.py

@@ -1,11 +1,16 @@
 import datetime
-from typing import Optional, Tuple
+from typing import TYPE_CHECKING, Optional, Tuple
 
 from aiobotocore.client import AioBaseClient
-from aiobotocore.session import get_session, AioSession
+from aiobotocore.session import AioSession, get_session
 
 from fastapi_cache.backends import Backend
 
+if TYPE_CHECKING:
+    from types_aiobotocore_dynamodb import DynamoDBClient
+else:
+    DynamoDBClient = AioBaseClient
+
 
 class DynamoBackend(Backend):
     """
@@ -25,14 +30,18 @@ class DynamoBackend(Backend):
         >> FastAPICache.init(dynamodb)
     """
 
+    client: DynamoDBClient
+    session: AioSession
+    table_name: str
+    region: Optional[str]
+
     def __init__(self, table_name: str, region: Optional[str] = None) -> None:
         self.session: AioSession = get_session()
-        self.client: Optional[AioBaseClient] = None  # Needs async init
         self.table_name = table_name
         self.region = region
 
     async def init(self) -> None:
-        self.client = await self.session.create_client(
+        self.client = await self.session.create_client(  # pyright: ignore[reportUnknownMemberType]
             "dynamodb", region_name=self.region
         ).__aenter__()
 
@@ -60,6 +69,7 @@ class DynamoBackend(Backend):
         response = await self.client.get_item(TableName=self.table_name, Key={"key": {"S": key}})
         if "Item" in response:
             return response["Item"].get("value", {}).get("B")
+        return None
 
     async def set(self, key: str, value: bytes, expire: Optional[int] = None) -> None:
         ttl = (

fastapi_cache/backends/redis.py

@@ -13,18 +13,18 @@ class RedisBackend(Backend):
 
     async def get_with_ttl(self, key: str) -> Tuple[int, Optional[bytes]]:
         async with self.redis.pipeline(transaction=not self.is_cluster) as pipe:
-            return await pipe.ttl(key).get(key).execute()
+            return await pipe.ttl(key).get(key).execute()  # type: ignore[union-attr,no-any-return]
 
     async def get(self, key: str) -> Optional[bytes]:
-        return await self.redis.get(key)
+        return await self.redis.get(key)  # type: ignore[union-attr]
 
     async def set(self, key: str, value: bytes, expire: Optional[int] = None) -> None:
-        return await self.redis.set(key, value, ex=expire)
+        await self.redis.set(key, value, ex=expire)  # type: ignore[union-attr]
 
     async def clear(self, namespace: Optional[str] = None, key: Optional[str] = None) -> int:
         if namespace:
             lua = f"for i, name in ipairs(redis.call('KEYS', '{namespace}:*')) do redis.call('DEL', name); end"
-            return await self.redis.eval(lua, numkeys=0)
+            return await self.redis.eval(lua, numkeys=0)  # type: ignore[union-attr,no-any-return]
         elif key:
-            return await self.redis.delete(key)
+            return await self.redis.delete(key)  # type: ignore[union-attr]
         return 0

fastapi_cache/coder.py

@@ -8,28 +8,31 @@ import pendulum
 from fastapi.encoders import jsonable_encoder
 from pydantic import BaseConfig, ValidationError, fields
 from starlette.responses import JSONResponse
-from starlette.templating import _TemplateResponse as TemplateResponse
+from starlette.templating import (
+    _TemplateResponse as TemplateResponse,  # pyright: ignore[reportPrivateUsage]
+)
 
-_T = TypeVar("_T")
+_T = TypeVar("_T", bound=type)
 
 
-CONVERTERS: dict[str, Callable[[str], Any]] = {
+CONVERTERS: Dict[str, Callable[[str], Any]] = {
-    "date": lambda x: pendulum.parse(x, exact=True),
+    # Pendulum 3.0.0 adds parse to __all__, at which point these ignores can be removed
-    "datetime": lambda x: pendulum.parse(x, exact=True),
+    "date": lambda x: pendulum.parse(x, exact=True),  # type: ignore[attr-defined]
+    "datetime": lambda x: pendulum.parse(x, exact=True),  # type: ignore[attr-defined]
     "decimal": Decimal,
 }
 
 
 class JsonEncoder(json.JSONEncoder):
-    def default(self, obj: Any) -> Any:
+    def default(self, o: Any) -> Any:
-        if isinstance(obj, datetime.datetime):
+        if isinstance(o, datetime.datetime):
-            return {"val": str(obj), "_spec_type": "datetime"}
+            return {"val": str(o), "_spec_type": "datetime"}
-        elif isinstance(obj, datetime.date):
+        elif isinstance(o, datetime.date):
-            return {"val": str(obj), "_spec_type": "date"}
+            return {"val": str(o), "_spec_type": "date"}
-        elif isinstance(obj, Decimal):
+        elif isinstance(o, Decimal):
-            return {"val": str(obj), "_spec_type": "decimal"}
+            return {"val": str(o), "_spec_type": "decimal"}
         else:
-            return jsonable_encoder(obj)
+            return jsonable_encoder(o)
 
 
 def object_hook(obj: Any) -> Any:

fastapi_cache/decorator.py

@@ -2,7 +2,7 @@ import logging
 import sys
 from functools import wraps
 from inspect import Parameter, Signature, isawaitable, iscoroutinefunction
-from typing import Awaitable, Callable, Optional, Type, TypeVar
+from typing import Awaitable, Callable, List, Optional, Type, TypeVar, Union, cast
 
 if sys.version_info >= (3, 10):
     from typing import ParamSpec
@@ -29,14 +29,14 @@ def _augment_signature(signature: Signature, *extra: Parameter) -> Signature:
         return signature
 
     parameters = list(signature.parameters.values())
-    variadic_keyword_params = []
+    variadic_keyword_params: List[Parameter] = []
     while parameters and parameters[-1].kind is Parameter.VAR_KEYWORD:
         variadic_keyword_params.append(parameters.pop())
 
     return signature.replace(parameters=[*parameters, *extra, *variadic_keyword_params])
 
 
-def _locate_param(sig: Signature, dep: Parameter, to_inject: list[Parameter]) -> Parameter:
+def _locate_param(sig: Signature, dep: Parameter, to_inject: List[Parameter]) -> Parameter:
     """Locate an existing parameter in the decorated endpoint
 
     If not found, returns the injectable parameter, and adds it to the to_inject list.
@@ -56,9 +56,9 @@ def cache(
     expire: Optional[int] = None,
     coder: Optional[Type[Coder]] = None,
     key_builder: Optional[KeyBuilder] = None,
-    namespace: Optional[str] = "",
+    namespace: str = "",
     injected_dependency_namespace: str = "__fastapi_cache",
-) -> Callable[[Callable[P, Awaitable[R]]], Callable[P, Awaitable[R]]]:
+) -> Callable[[Callable[P, Awaitable[R]]], Callable[P, Awaitable[Union[R, Response]]]]:
     """
     cache all function
     :param namespace:
@@ -80,16 +80,16 @@ def cache(
         kind=Parameter.KEYWORD_ONLY,
     )
 
-    def wrapper(func: Callable[P, Awaitable[R]]) -> Callable[P, Awaitable[R]]:
+    def wrapper(func: Callable[P, Awaitable[R]]) -> Callable[P, Awaitable[Union[R, Response]]]:
         # get_typed_signature ensures that any forward references are resolved first
         wrapped_signature = get_typed_signature(func)
-        to_inject: list[Parameter] = []
+        to_inject: List[Parameter] = []
         request_param = _locate_param(wrapped_signature, injected_request, to_inject)
         response_param = _locate_param(wrapped_signature, injected_response, to_inject)
         return_type = get_typed_return_annotation(func)
 
         @wraps(func)
-        async def inner(*args: P.args, **kwargs: P.kwargs) -> R:
+        async def inner(*args: P.args, **kwargs: P.kwargs) -> Union[R, Response]:
             nonlocal coder
             nonlocal expire
             nonlocal key_builder
@@ -111,11 +111,11 @@ def cache(
                 else:
                     # sync, wrap in thread and return async
                     # see above why we have to await even although caller also awaits.
-                    return await run_in_threadpool(func, *args, **kwargs)
+                    return await run_in_threadpool(func, *args, **kwargs)  # type: ignore[arg-type]
 
             copy_kwargs = kwargs.copy()
-            request: Optional[Request] = copy_kwargs.pop(request_param.name, None)
+            request: Optional[Request] = copy_kwargs.pop(request_param.name, None)  # type: ignore[assignment]
-            response: Optional[Response] = copy_kwargs.pop(response_param.name, None)
+            response: Optional[Response] = copy_kwargs.pop(response_param.name, None)  # type: ignore[assignment]
             if (
                 request and request.headers.get("Cache-Control") in ("no-store", "no-cache")
             ) or not FastAPICache.get_enable():
@@ -137,17 +137,18 @@ def cache(
             )
             if isawaitable(cache_key):
                 cache_key = await cache_key
+            assert isinstance(cache_key, str)
 
             try:
-                ttl, ret = await backend.get_with_ttl(cache_key)
+                ttl, cached = await backend.get_with_ttl(cache_key)
             except Exception:
                 logger.warning(
                     f"Error retrieving cache key '{cache_key}' from backend:", exc_info=True
                 )
-                ttl, ret = 0, None
+                ttl, cached = 0, None
             if not request:
-                if ret is not None:
+                if cached is not None:
-                    return coder.decode_as_type(ret, type_=return_type)
+                    return cast(R, coder.decode_as_type(cached, type_=return_type))
                 ret = await ensure_async_func(*args, **kwargs)
                 try:
                     await backend.set(cache_key, coder.encode(ret), expire)
@@ -161,15 +162,15 @@ def cache(
                 return await ensure_async_func(*args, **kwargs)
 
             if_none_match = request.headers.get("if-none-match")
-            if ret is not None:
+            if cached is not None:
                 if response:
                     response.headers["Cache-Control"] = f"max-age={ttl}"
-                    etag = f"W/{hash(ret)}"
+                    etag = f"W/{hash(cached)}"
                     if if_none_match == etag:
                         response.status_code = 304
                         return response
                     response.headers["ETag"] = etag
-                return coder.decode_as_type(ret, type_=return_type)
+                return cast(R, coder.decode_as_type(cached, type_=return_type))
 
             ret = await ensure_async_func(*args, **kwargs)
             encoded_ret = coder.encode(ret)
@@ -179,12 +180,13 @@ def cache(
             except Exception:
                 logger.warning(f"Error setting cache key '{cache_key}' in backend:", exc_info=True)
 
+            if response:
                 response.headers["Cache-Control"] = f"max-age={expire}"
                 etag = f"W/{hash(encoded_ret)}"
                 response.headers["ETag"] = etag
             return ret
 
-        inner.__signature__ = _augment_signature(wrapped_signature, *to_inject)
+        inner.__signature__ = _augment_signature(wrapped_signature, *to_inject)  # type: ignore[attr-defined]
         return inner
 
     return wrapper

fastapi_cache/key_builder.py

@@ -1,5 +1,5 @@
 import hashlib
-from typing import Any, Callable, Optional
+from typing import Any, Callable, Dict, Optional, Tuple
 
 from starlette.requests import Request
 from starlette.responses import Response
@@ -8,10 +8,11 @@ from starlette.responses import Response
 def default_key_builder(
     func: Callable[..., Any],
     namespace: str = "",
+    *,
     request: Optional[Request] = None,
     response: Optional[Response] = None,
-    args: Optional[tuple[Any, ...]] = None,
+    args: Tuple[Any, ...],
-    kwargs: Optional[dict[str, Any]] = None,
+    kwargs: Dict[str, Any],
 ) -> str:
     cache_key = hashlib.md5(  # nosec:B303
         f"{func.__module__}:{func.__name__}:{args}:{kwargs}".encode()

fastapi_cache/types.py

@@ -1,7 +1,8 @@
-from typing import Any, Awaitable, Callable, Optional, Protocol, Union
+from typing import Any, Awaitable, Callable, Dict, Optional, Tuple, Union
 
 from starlette.requests import Request
 from starlette.responses import Response
+from typing_extensions import Protocol
 
 
 _Func = Callable[..., Any]
@@ -10,12 +11,12 @@ _Func = Callable[..., Any]
 class KeyBuilder(Protocol):
     def __call__(
         self,
-        _function: _Func,
+        __function: _Func,
-        _namespace: str = ...,
+        __namespace: str = ...,
         *,
         request: Optional[Request] = ...,
         response: Optional[Response] = ...,
-        args: tuple[Any, ...] = ...,
+        args: Tuple[Any, ...],
-        kwargs: dict[str, Any] = ...,
+        kwargs: Dict[str, Any],
     ) -> Union[Awaitable[str], str]:
         ...

pyproject.toml

@@ -22,7 +22,7 @@ redis = { version = "^4.2.0rc1", optional = true }
 aiomcache = { version = "*", optional = true }
 pendulum = "*"
 aiobotocore = { version = "^1.4.1", optional = true }
-typing-extensions = { version = ">=4.1.0", markers = "python_version < \"3.10\"" }
+typing-extensions = { version = ">=4.1.0" }
 aiohttp = { version = ">=3.8.3", markers = "python_version >= \"3.11\"" }
 
 [tool.poetry.group.dev.dependencies]
@@ -33,6 +33,10 @@ pytest = "*"
 requests = "*"
 coverage = "^6.5.0"
 httpx = "*"
+mypy = "^1.2.0"
+types-redis = "^4.5.4.2"
+pyright = "^1.1.306"
+types-aiobotocore = { extras = ["dynamodb"], version = "^2.5.0.post2" }
 
 [build-system]
 requires = ["poetry>=0.12"]
@@ -47,3 +51,31 @@ all = ["redis", "aiomcache", "aiobotocore"]
 [tool.black]
 line-length = 100
 target-version = ['py36', 'py37', 'py38', 'py39']
+
+[tool.mypy]
+files = ["fastapi_cache", "examples", "tests"]
+python_version = "3.7"
+# equivalent of --strict
+warn_unused_configs = true
+disallow_any_generics = true
+disallow_subclassing_any = true
+disallow_untyped_calls = true
+disallow_untyped_defs = true
+disallow_incomplete_defs = true
+check_untyped_defs = true
+disallow_untyped_decorators = true
+warn_redundant_casts = true
+warn_unused_ignores = true
+warn_return_any = true
+no_implicit_reexport = true
+strict_equality = true
+strict_concatenate = true
+
+[[tool.mypy.overrides]]
+module = "examples.*.main"
+ignore_errors = true
+
+[tool.pyright]
+include = ["fastapi_cache", "tests", "examples"]
+strict = ["fastapi_cache", "tests"]
+pythonVersion = "3.7"

tests/test_codecs.py

@@ -1,5 +1,5 @@
 from dataclasses import dataclass
-from typing import Any, Optional
+from typing import Any, Optional, Tuple, Type
 
 import pytest
 from pydantic import BaseModel, ValidationError
@@ -46,14 +46,14 @@ def test_pickle_coder(value: Any) -> None:
     [
         (1, None),
         ("some_string", None),
-        ((1, 2), tuple[int, int]),
+        ((1, 2), Tuple[int, int]),
         ([1, 2, 3], None),
         ({"some_key": 1, "other_key": 2}, None),
         (DCItem(name="foo", price=42.0, description="some dataclass item", tax=0.2), DCItem),
         (PDItem(name="foo", price=42.0, description="some pydantic item", tax=0.2), PDItem),
     ],
 )
-def test_json_coder(value: Any, return_type) -> None:
+def test_json_coder(value: Any, return_type: Type[Any]) -> None:
     encoded_value = JsonCoder.encode(value)
     assert isinstance(encoded_value, bytes)
     decoded_value = JsonCoder.decode_as_type(encoded_value, type_=return_type)

tests/test_decorator.py

@@ -1,5 +1,5 @@
 import time
-from typing import Generator
+from typing import Generator, Any
 
 import pendulum
 import pytest
@@ -11,7 +11,7 @@ from fastapi_cache.backends.inmemory import InMemoryBackend
 
 
 @pytest.fixture(autouse=True)
-def init_cache() -> Generator:
+def init_cache() -> Generator[Any, Any, None]:
     FastAPICache.init(InMemoryBackend())
     yield
     FastAPICache.reset()
@@ -21,34 +21,34 @@ def test_datetime() -> None:
     with TestClient(app) as client:
         response = client.get("/datetime")
         now = response.json().get("now")
-        now_ = pendulum.now().replace(microsecond=0)
+        now_ = pendulum.now().replace(microsecond=0)  # type: ignore[no-untyped-call]
-        assert pendulum.parse(now).replace(microsecond=0) == now_
+        assert pendulum.parse(now).replace(microsecond=0) == now_  # type: ignore[attr-defined]
         response = client.get("/datetime")
         now = response.json().get("now")
-        assert pendulum.parse(now).replace(microsecond=0) == now_
+        assert pendulum.parse(now).replace(microsecond=0) == now_  # type: ignore[attr-defined]
         time.sleep(3)
         response = client.get("/datetime")
         now = response.json().get("now")
-        now = pendulum.parse(now).replace(microsecond=0)
+        now = pendulum.parse(now).replace(microsecond=0)  # type: ignore[attr-defined]
         assert now != now_
-        assert now == pendulum.now().replace(microsecond=0)
+        assert now == pendulum.now().replace(microsecond=0)  # type: ignore[no-untyped-call]
 
 
 def test_date() -> None:
     """Test path function without request or response arguments."""
     with TestClient(app) as client:
         response = client.get("/date")
-        assert pendulum.parse(response.json()) == pendulum.today()
+        assert pendulum.parse(response.json()) == pendulum.today()  # type: ignore[attr-defined]
 
         # do it again to test cache
         response = client.get("/date")
-        assert pendulum.parse(response.json()) == pendulum.today()
+        assert pendulum.parse(response.json()) == pendulum.today()  # type: ignore[attr-defined]
 
         # now test with cache disabled, as that's a separate code path
-        FastAPICache._enable = False
+        FastAPICache._enable = False  # pyright: ignore[reportPrivateUsage]
         response = client.get("/date")
-        assert pendulum.parse(response.json()) == pendulum.today()
+        assert pendulum.parse(response.json()) == pendulum.today()  # type: ignore[attr-defined]
-        FastAPICache._enable = True
+        FastAPICache._enable = True  # pyright: ignore[reportPrivateUsage]
 
 
 def test_sync() -> None: