Added cache

src/cpl-core/cpl/core/utils/cache.py

@@ -0,0 +1,100 @@
+import threading
+import time
+from typing import Generic
+
+from cpl.core.typing import T
+
+
+class Cache(Generic[T]):
+    def __init__(self, default_ttl: int = None, cleanup_interval: int = 60, t: type = None):
+        self._store = {}
+        self._default_ttl = default_ttl
+        self._lock = threading.Lock()
+        self._cleanup_interval = cleanup_interval
+        self._stop_event = threading.Event()
+
+        self._type = t
+
+        # Start background cleanup thread
+        self._thread = threading.Thread(target=self._auto_cleanup, daemon=True)
+        self._thread.start()
+
+    def set(self, key: str, value: T, ttl: int = None) -> None:
+        """Store a value in the cache with optional TTL override."""
+        expire_at = None
+        ttl = ttl if ttl is not None else self._default_ttl
+        if ttl is not None:
+            expire_at = time.time() + ttl
+
+        with self._lock:
+            self._store[key] = (value, expire_at)
+
+    def get(self, key: str) -> T | None:
+        """Retrieve a value from the cache if not expired."""
+        with self._lock:
+            item = self._store.get(key)
+            if not item:
+                return None
+            value, expire_at = item
+            if expire_at and expire_at < time.time():
+                # Expired -> remove and return None
+                del self._store[key]
+                return None
+            return value
+
+    def get_all(self) -> list[T]:
+        """Retrieve all non-expired values from the cache."""
+        now = time.time()
+        with self._lock:
+            valid_items = []
+            expired_keys = []
+            for k, (v, exp) in self._store.items():
+                if exp and exp < now:
+                    expired_keys.append(k)
+                else:
+                    valid_items.append(v)
+            for k in expired_keys:
+                del self._store[k]
+            return valid_items
+
+    def has(self, key: str) -> bool:
+        """Check if a key exists and is not expired."""
+        with self._lock:
+            item = self._store.get(key)
+            if not item:
+                return False
+            _, expire_at = item
+            if expire_at and expire_at < time.time():
+                # Expired -> remove and return False
+                del self._store[key]
+                return False
+            return True
+
+    def delete(self, key: str) -> None:
+        """Remove an item from the cache."""
+        with self._lock:
+            self._store.pop(key, None)
+
+    def clear(self) -> None:
+        """Clear the entire cache."""
+        with self._lock:
+            self._store.clear()
+
+    def _auto_cleanup(self):
+        """Background thread to clean expired items."""
+        while not self._stop_event.is_set():
+            self.cleanup()
+            self._stop_event.wait(self._cleanup_interval)
+
+    def cleanup(self) -> None:
+        """Remove expired items immediately."""
+        now = time.time()
+        with self._lock:
+            expired_keys = [k for k, (_, exp) in self._store.items() if exp and exp < now]
+            for k in expired_keys:
+                del self._store[k]
+
+    def stop(self):
+        """Stop the background cleanup thread."""
+        self._stop_event.set()
+        self._thread.join()