refactor: replace algorithm dict lookup with match/case pattern

fastapi_traffic/core/algorithms.py

@@ -26,7 +26,7 @@ class Algorithm(str, Enum):
 class BaseAlgorithm(ABC):
     """Base class for rate limiting algorithms."""
 
-    __slots__ = ("limit", "window_size", "backend", "burst_size")
+    __slots__ = ("backend", "burst_size", "limit", "window_size")
 
     def __init__(
         self,
@@ -450,17 +450,24 @@ def get_algorithm(
     burst_size: int | None = None,
 ) -> BaseAlgorithm:
     """Factory function to create algorithm instances."""
-    algorithm_map: dict[Algorithm, type[BaseAlgorithm]] = {
-        Algorithm.TOKEN_BUCKET: TokenBucketAlgorithm,
-        Algorithm.SLIDING_WINDOW: SlidingWindowAlgorithm,
-        Algorithm.FIXED_WINDOW: FixedWindowAlgorithm,
-        Algorithm.LEAKY_BUCKET: LeakyBucketAlgorithm,
-        Algorithm.SLIDING_WINDOW_COUNTER: SlidingWindowCounterAlgorithm,
-    }
-
-    algorithm_class = algorithm_map.get(algorithm)
-    if algorithm_class is None:
-        msg = f"Unknown algorithm: {algorithm}"
-        raise ValueError(msg)
-
-    return algorithm_class(limit, window_size, backend, burst_size=burst_size)
+    match algorithm:
+        case Algorithm.TOKEN_BUCKET:
+            return TokenBucketAlgorithm(
+                limit, window_size, backend, burst_size=burst_size
+            )
+        case Algorithm.SLIDING_WINDOW:
+            return SlidingWindowAlgorithm(
+                limit, window_size, backend, burst_size=burst_size
+            )
+        case Algorithm.FIXED_WINDOW:
+            return FixedWindowAlgorithm(
+                limit, window_size, backend, burst_size=burst_size
+            )
+        case Algorithm.LEAKY_BUCKET:
+            return LeakyBucketAlgorithm(
+                limit, window_size, backend, burst_size=burst_size
+            )
+        case Algorithm.SLIDING_WINDOW_COUNTER:
+            return SlidingWindowCounterAlgorithm(
+                limit, window_size, backend, burst_size=burst_size
+            )