From 6cc1e65abbf48a5ba3a14abd1ea8bdbe6db1d873 Mon Sep 17 00:00:00 2001
From: Jegor Kitskerkin <jegor.kitskerkin@gmail.com>
Date: Thu, 11 Aug 2022 15:03:41 +0200
Subject: [PATCH] Add support for async key_builder

---
 fastapi_cache/decorator.py | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/fastapi_cache/decorator.py b/fastapi_cache/decorator.py
index ed1a30c..98e20ae 100644
--- a/fastapi_cache/decorator.py
+++ b/fastapi_cache/decorator.py
@@ -47,9 +47,25 @@ def cache(
             key_builder = key_builder or FastAPICache.get_key_builder()
             backend = FastAPICache.get_backend()
 
-            cache_key = key_builder(
-                func, namespace, request=request, response=response, args=args, kwargs=copy_kwargs
-            )
+            if inspect.iscoroutinefunction(key_builder):
+                cache_key = await key_builder(
+                    func,
+                    namespace,
+                    request=request,
+                    response=response,
+                    args=args,
+                    kwargs=copy_kwargs
+                )
+            else:
+                cache_key = key_builder(
+                    func,
+                    namespace,
+                    request=request,
+                    response=response,
+                    args=args,
+                    kwargs=copy_kwargs
+                )
+
             ttl, ret = await backend.get_with_ttl(cache_key)
             if not request:
                 if ret is not None: