fix(redis_cache.py): support pipeline redis lpop for older redis vers… (#11425)

* fix(redis_cache.py): support pipeline redis lpop for older redis versions

Fixes https://github.com/BerriAI/litellm/issues/10379

* test: add mock host

litellm/caching/redis_cache.py

@@ -1122,6 +1122,21 @@ class RedisCache(BaseCache):
             )
             raise e
 
+    async def handle_lpop_count_for_older_redis_versions(
+        self, pipe: pipeline, key: str, count: int
+    ) -> List[bytes]:
+        result: List[bytes] = []
+        for _ in range(count):
+            pipe.lpop(key)
+            results = await pipe.execute()
+
+            # Filter out None values and decode bytes
+            for r in results:
+                if r is not None:
+                    result.append(r)
+
+        return result
+
     async def async_lpop(
         self,
         key: str,
@@ -1133,7 +1148,22 @@ class RedisCache(BaseCache):
         start_time = time.time()
         print_verbose(f"LPOP from Redis list: key: {key}, count: {count}")
         try:
-            result = await _redis_client.lpop(key, count)
+            major_version: int = 7
+            # Check Redis version and use appropriate method
+            if self.redis_version != "Unknown":
+                # Parse version string like "6.0.0" to get major version
+                major_version = int(self.redis_version.split(".")[0])
+
+            if count is not None and major_version < 7:
+                # For Redis < 7.0, use pipeline to execute multiple LPOP commands
+                async with _redis_client.pipeline(transaction=False) as pipe:
+                    result = await self.handle_lpop_count_for_older_redis_versions(
+                        pipe, key, count
+                    )
+            else:
+                # For Redis >= 7.0 or when count is None, use native LPOP with count
+                result = await _redis_client.lpop(key, count)
+
             ## LOGGING ##
             end_time = time.time()
             _duration = end_time - start_time

tests/test_litellm/caching/test_redis_cache.py

@@ -94,3 +94,29 @@ async def test_redis_cache_async_batch_get_cache(monkeypatch, redis_no_ping):
         assert result["key1"] == {"key1": "value1"}
         assert result["key2"] is None
         assert result["key3"] == {"key3": "value3"}
+
+
+@pytest.mark.asyncio
+async def test_handle_lpop_count_for_older_redis_versions(monkeypatch):
+    """Test the helper method that handles LPOP with count for Redis versions < 7.0"""
+    monkeypatch.setenv("REDIS_HOST", "https://my-test-host")
+    # Create RedisCache instance
+    redis_cache = RedisCache()
+
+    # Create a mock pipeline
+    mock_pipeline = AsyncMock()
+    # Set up execute to return different values each time
+    mock_pipeline.execute.side_effect = [
+        [b"value1"],  # First execute returns first value
+        [b"value2"],  # Second execute returns second value
+    ]
+
+    # Test the helper method
+    result = await redis_cache.handle_lpop_count_for_older_redis_versions(
+        pipe=mock_pipeline, key="test_key", count=2
+    )
+
+    # Verify results
+    assert result == [b"value1", b"value2"]
+    assert mock_pipeline.lpop.call_count == 2
+    assert mock_pipeline.execute.call_count == 2