🚧 api: building redis cache decorator

api/advent22_api/core/dav/dec.py

@@ -74,30 +74,25 @@ def args_slice(func: Callable[P, R], *args: Iterable) -> tuple:
     return tuple(*args)
 
 
+def cache_key(func: Callable[P, R], *args: P.args, **kwargs: P.kwargs) -> str:
+    """Return a cache key for use with cached methods."""
+
+    kwargs_by_key = sorted(kwargs.items(), key=lambda kv: kv[0])
+
+    parts = chain(
+        (qualified_name(func),),
+        # positional args
+        (repr(arg) for arg in args_slice(func, args)),
+        # keyword args
+        (f"{k}={v!r}" for k, v in kwargs_by_key),
+    )
+
+    return ":".join(parts)
+
+
 def redis_cached(cfg: Config) -> Callable[[Callable[P, R]], Callable[P, R]]:
     """ """
 
-    def cache_key(func: Callable[P, R], *args: P.args, **kwargs: P.kwargs) -> str:
-        """Return a cache key for use with cached methods."""
-
-        kwargs_by_key = sorted(kwargs.items(), key=lambda kv: kv[0])
-
-        parts = chain(
-            (qualified_name(func),),
-            # positional args
-            (repr(arg) for arg in args_slice(func, args)),
-            # keyword args
-            (f"{k}={v!r}" for k, v in kwargs_by_key),
-        )
-
-        if cfg.prefix is not None:
-            parts = chain(
-                (cfg.prefix,),
-                parts,
-            )
-
-        return ":".join(parts)
-
     def decorator(func: Callable[P, R]) -> Callable[P, R]:
         """ """
 
@@ -105,6 +100,9 @@ def redis_cached(cfg: Config) -> Callable[[Callable[P, R]], Callable[P, R]]:
         def wrapper(*args: P.args, **kwargs: P.kwargs) -> R:
             key = cache_key(func, *args, **kwargs)
 
+            if cfg.prefix is not None:
+                key = f"{cfg.prefix}:{key}"
+
             # pre-hook
             result = func(*args, **kwargs)
             # post-hook