Fix KeyError in async cluster - initialize before execute multi key c…

…ommands (#2439)

* Fix KeyError in async cluster

* link to issue

* typo

redis/commands/cluster.py

@@ -316,6 +316,25 @@ async def _split_command_across_slots(self, command: str, *keys: KeyT) -> int:
         # Sum up the reply from each command
         return sum(await self._execute_pipeline_by_slot(command, slots_to_keys))
 
+    async def _execute_pipeline_by_slot(
+        self, command: str, slots_to_args: Mapping[int, Iterable[EncodableT]]
+    ) -> List[Any]:
+        if self._initialize:
+            await self.initialize()
+        read_from_replicas = self.read_from_replicas and command in READ_COMMANDS
+        pipe = self.pipeline()
+        [
+            pipe.execute_command(
+                command,
+                *slot_args,
+                target_nodes=[
+                    self.nodes_manager.get_node_from_slot(slot, read_from_replicas)
+                ],
+            )
+            for slot, slot_args in slots_to_args.items()
+        ]
+        return await pipe.execute()
+
 
 class ClusterManagementCommands(ManagementCommands):
     """

tests/test_asyncio/test_cluster.py

@@ -812,6 +812,15 @@ async def test_unlink(self, r: RedisCluster) -> None:
         await asyncio.sleep(0.1)
         assert await r.unlink(*d.keys()) == 0
 
+    async def test_initialize_before_execute_multi_key_command(
+        self, request: FixtureRequest
+    ) -> None:
+        # Test for issue https://github.com/redis/redis-py/issues/2437
+        url = request.config.getoption("--redis-url")
+        r = RedisCluster.from_url(url)
+        assert 0 == await r.exists("a", "b", "c")
+        await r.close()
+
     @skip_if_redis_enterprise()
     async def test_cluster_myid(self, r: RedisCluster) -> None:
         node = r.get_random_node()