add more contrib modules

cashews/contrib/__init__.py

@@ -1,3 +1,7 @@
+"""
+Here modules with auto setup
+"""
+
 try:
     from . import _starlette
 except ImportError:

cashews/contrib/fastapi.py

@@ -0,0 +1,136 @@
+import contextlib
+from contextlib import nullcontext
+from contextvars import ContextVar
+from hashlib import blake2s
+from typing import List, Optional
+
+from starlette.middleware.base import BaseHTTPMiddleware, RequestResponseEndpoint
+from starlette.requests import Request
+from starlette.responses import Response
+from starlette.types import ASGIApp
+
+from cashews import Cache, Command, cache, invalidate_further
+
+_CACHE_MAX_AGE = ContextVar("cache_control_max_age")
+
+_CACHE_CONTROL_HEADER = "Cache-Control"
+_AGE_HEADER = "Age"
+_ETAG_HEADER = "ETag"
+_IF_NOT_MATCH_HEADER = "If-None-Match"
+_CLEAR_CACHE_HEADER = "Clear-Site-Data"
+
+_NO_CACHE = "no-cache"  # disable GET
+_NO_STORE = "no-store"  # disable GET AND SET
+_MAX_AGE = "max-age="
+_ONLY_IF_CACHED = "only-if-cached"
+_PRIVATE = "private"
+_PUBLIC = "public"
+
+_CLEAR_CACHE_HEADER_VALUE = "cache"
+
+
+def cache_control_condition():
+    pass
+
+
+def cache_control_ttl():
+    pass
+
+
+class CacheRequestControlMiddleware(BaseHTTPMiddleware):
+    def __init__(self, app: ASGIApp, cache_instance: Cache = cache, methods: List[str] = ("get",), private=True):
+        self._private = private
+        self._cache = cache_instance
+        self._methods = methods
+        super().__init__(app)
+
+    async def dispatch(self, request: Request, call_next: RequestResponseEndpoint) -> Response:
+        context = nullcontext()
+        cache_control_value = request.headers.get(_CACHE_CONTROL_HEADER)
+        if request.method.lower() not in self._methods:
+            return await call_next(request)
+        to_disable = self._to_disable(cache_control_value)
+        if to_disable:
+            context = self._cache.disabling(*to_disable)
+        with context, self.max_age(cache_control_value), self._cache.detect as detector:
+            response = await call_next(request)
+            calls = detector.calls_list
+            if calls:
+                key, _ = calls[0]
+                expire = await self._cache.get_expire(key)
+                if expire:
+                    response.headers[
+                        _CACHE_CONTROL_HEADER
+                    ] = f"{_PRIVATE if self._private else _PUBLIC}, {_MAX_AGE}{expire}"
+                    response.headers[_AGE_HEADER] = f"{expire}"
+            else:
+                response.headers[_CACHE_CONTROL_HEADER] = _NO_CACHE
+            return response
+
+    @contextlib.contextmanager
+    def max_age(self, cache_control_value: Optional[str]):
+        if not cache_control_value:
+            yield
+            return
+        _max_age = self._get_max_age(cache_control_value)
+        reset_token = None
+        if _max_age:
+            reset_token = _CACHE_MAX_AGE.set(_max_age)
+        try:
+            yield
+        finally:
+            if reset_token:
+                _CACHE_MAX_AGE.reset(reset_token)
+
+    @staticmethod
+    def _to_disable(cache_control_value: Optional[str]) -> tuple[Command]:
+        if cache_control_value == _NO_CACHE:
+            return (Command.GET,)
+        if cache_control_value == _NO_STORE:
+            return Command.GET, Command.SET
+        return tuple()
+
+    @staticmethod
+    def _get_max_age(cache_control_value: str) -> int:
+        if not cache_control_value.startswith(_MAX_AGE):
+            return 0
+        try:
+            return int(cache_control_value.replace(_MAX_AGE, ""))
+        except (ValueError, TypeError):
+            return 0
+
+
+class CacheEtagMiddleware(BaseHTTPMiddleware):
+    def __init__(self, app: ASGIApp, cache_instance: Cache = cache):
+        self._cache = cache_instance
+        super().__init__(app)
+
+    async def dispatch(self, request: Request, call_next: RequestResponseEndpoint):
+        etag = request.headers.get(_IF_NOT_MATCH_HEADER)
+        if etag and await self._cache.exists(etag):
+            return Response(status_code=304)
+
+        with self._cache.detect as detector:
+            response = await call_next(request)
+            calls = detector.calls_list
+            if not calls:
+                return response
+
+            key, _ = calls[0]
+            response.headers[_ETAG_HEADER] = await self._get_etag(key)
+        return response
+
+    async def _get_etag(self, key: str) -> str:
+        data = await self._cache.get_raw(key)
+        expire = await self._cache.get_expire(key)
+        etag = blake2s(data).hexdigest()
+        await self._cache.set(etag, True, expire=expire)
+        return etag
+
+
+class CacheDeleteMiddleware(BaseHTTPMiddleware):
+    async def dispatch(self, request: Request, call_next: RequestResponseEndpoint):
+        if request.headers.get(_CLEAR_CACHE_HEADER) == _CLEAR_CACHE_HEADER_VALUE:
+            with invalidate_further():
+                return await call_next(request)
+        return await call_next(request)

cashews/contrib/prometheus.py

@@ -0,0 +1,28 @@
+from typing import Optional
+
+from prometheus_client import Histogram
+
+from cashews import cache
+from cashews._typing import Middleware
+from cashews.backends.interface import Backend
+from cashews.commands import Command
+
+
+def create_metrics_middleware(latency_metric: Optional[Histogram] = None, with_tag: bool = False) -> Middleware:
+    _DEFAULT_METRIC = Histogram(
+        "cashews_operations_latency_seconds",
+        "Latency of different operations with a cache",
+        labels=["operation", "backend_class"] if not with_tag else ["operation", "backend_class", "tag"],
+    )
+    _latency_metric = latency_metric or _DEFAULT_METRIC
+
+    async def metrics_middleware(call, cmd: Command, backend: Backend, *args, **kwargs):
+        with _latency_metric as metric:
+            metric.labels(operation=cmd.value, backend_class=backend.__name__)
+            if with_tag and "key" in kwargs:
+                tags = cache.get_key_tags(kwargs["key"])
+                if tags:
+                    metric.labels(tag=tags[0])
+            return await call(*args, **kwargs)
+
+    return metrics_middleware

cashews/decorators/cache/defaults.py

@@ -11,21 +11,23 @@ class CacheDetect:
     __slots__ = ("_value", "_unset_token", "_previous_level")
 
     def __init__(self, previous_level=0, unset_token=None):
-        self._value = {}
+        self._value = []
         self._unset_token = unset_token
         self._previous_level = previous_level
 
     def _set(self, key: Key, **kwargs: Any) -> None:
-        self._value.setdefault(key, []).append(kwargs)
+        self._value.append((key, [kwargs]))
 
     @property
     def calls(self):
         return dict(self._value)
 
-    keys = calls  # backward compatibility
+    @property
+    def calls_list(self):
+        return self._value.copy()
 
     def clear(self):
-        self._value = {}
+        self._value = []
 
 
 _level = ContextVar("level", default=0)

cashews/ttl.py

@@ -9,13 +9,13 @@ def ttl_to_seconds(
 ) -> Union[int, None, float]:
     if ttl is None:
         return None
-    _type = type(ttl)
+    _type = type(ttl)  # isinstance is slow
+    if _type == str:
+        return _ttl_from_str(ttl)
     if _type == int:
         return ttl
     if _type == timedelta:
         return ttl.total_seconds()
-    if _type == str:
-        return _ttl_from_str(ttl)
     if callable(ttl) and with_callable:
         try:
             ttl = ttl(*args, result=result, **kwargs)

cashews/wrapper/decorators.py

@@ -10,7 +10,7 @@
 from .wrapper import Wrapper
 
 
-def _thunder_protection(func: Callable) -> Callable:
+def _skip_thunder_protection(func: Callable) -> Callable:
     return func
 
 
@@ -36,12 +36,13 @@ def _decorator(func: AsyncCallable_T) -> AsyncCallable_T:
                 decor_kwargs["condition"] = condition
 
             decorator = decorator_fabric(self, **decor_kwargs)(func)
-            thunder_protection = _thunder_protection
+            thunder_protection = _skip_thunder_protection
             if protected:
                 thunder_protection = decorators.thunder_protection(key=decor_kwargs.get("key"))
 
             @wraps(func)
             async def _call(*args, **kwargs):
+                self._check_setup()
                 if self.is_full_disable:
                     return await func(*args, **kwargs)
                 if lock:
@@ -69,12 +70,13 @@ def _decorator(func: AsyncCallable_T) -> AsyncCallable_T:
 
             @wraps(func)
             async def _call(*args, **kwargs):
+                self._check_setup()
                 if self.is_full_disable:
                     return await func(*args, **kwargs)
                 with decorators.context_cache_detect as detect:
 
                     def new_condition(result, _args, _kwargs, key):
-                        if detect.keys:
+                        if detect.calls:
                             return False
                         return _condition(result, _args, _kwargs, key=key) if _condition else result is not None
 

cashews/wrapper/wrapper.py

@@ -30,8 +30,7 @@ def _get_backend_and_config(self, key: Key) -> Tuple[Backend, Tuple[Middleware,
         for prefix in sorted(self._backends.keys(), reverse=True):
             if key.startswith(prefix):
                 return self._backends[prefix]
-        if self.default_prefix not in self._backends:
-            raise NotConfiguredError("run `cache.setup(...)` before using cache")
+        self._check_setup()
 
     def _get_backend(self, key: Key) -> Backend:
         backend, _ = self._get_backend_and_config(key)
@@ -62,6 +61,13 @@ def setup(self, settings_url: str, middlewares: Tuple = (), prefix: str = defaul
         self._add_backend(backend, middlewares, prefix)
         return backend
 
+    def is_setup(self) -> bool:
+        return bool(self._backends)
+
+    def _check_setup(self):
+        if not self._backends:
+            raise NotConfiguredError("run `cache.setup(...)` before using cache")
+
     def _add_backend(self, backend: Backend, middlewares=(), prefix: str = default_prefix):
         self._backends[prefix] = (
             backend,

examples/fastapi_app.py

@@ -7,16 +7,20 @@
 from fastapi import FastAPI, Header, Query
 from fastapi.responses import StreamingResponse
 
-from cashews import Command, cache
+from cashews import cache
+from cashews.contrib.fastapi import CacheDeleteMiddleware, CacheEtagMiddleware, CacheRequestControlMiddleware
 
 app = FastAPI()
-cache.setup(os.environ.get("CACHE_URI", "redis://?client_side=True"))
+app.add_middleware(CacheDeleteMiddleware)
+app.add_middleware(CacheEtagMiddleware)
+app.add_middleware(CacheRequestControlMiddleware)
+cache.setup(os.environ.get("CACHE_URI", "redis://"))
 KB = 1024
 
 
 @app.get("/")
 @cache.failover(ttl="1h")
-@cache.slice_rate_limit(10, "1m")
+@cache.slice_rate_limit(10, "3m")
 @cache(ttl="10m", key="simple:{user_agent}", time_condition="1s")
 async def simple(user_agent: str = Header("No")):
     await asyncio.sleep(1.1)
@@ -56,25 +60,6 @@ async def add_process_time_header(request, call_next):
     return response
 
 
-@app.middleware("http")
-async def add_from_cache_headers(request, call_next):
-    with cache.detect as detector:
-        response = await call_next(request)
-        if request.method.lower() != "get":
-            return response
-        if detector.calls:
-            response.headers["X-From-Cache-keys"] = ";".join(detector.calls.keys())
-    return response
-
-
-@app.middleware("http")
-async def disable_middleware(request, call_next):
-    if request.headers.get("X-No-Cache"):
-        with cache.disabling(Command.GET):
-            return await call_next(request)
-    return await call_next(request)
-
-
 if __name__ == "__main__":
     import uvicorn
 

tests/conftest.py

@@ -74,13 +74,25 @@ async def _backend(request, redis_dsn, backend_factory):
         from cashews.backends.redis import Redis
 
         backend = backend_factory(
-            Redis, redis_dsn, hash_key=None, max_connections=20, suppress=False, socket_timeout=10
+            Redis,
+            redis_dsn,
+            hash_key=None,
+            max_connections=20,
+            suppress=False,
+            socket_timeout=10,
+            wait_for_connection_timeout=1,
         )
     elif request.param == "redis_hash":
         from cashews.backends.redis import Redis
 
         backend = backend_factory(
-            Redis, redis_dsn, hash_key=uuid4().hex, max_connections=20, suppress=False, socket_timeout=10
+            Redis,
+            redis_dsn,
+            hash_key=uuid4().hex,
+            max_connections=20,
+            suppress=False,
+            socket_timeout=10,
+            wait_for_connection_timeout=1,
         )
     elif request.param == "redis_cs":
         from cashews.backends.redis.client_side import BcastClientSide