feat(sdk-py): define aclose method to LangGraphClient (#5931)

This PR adds an aclose method to the LangGraphClient.

When using the client in a FastAPI application, it's common to share a
single instance across the application's lifespan. The absence of an
aclose method makes it difficult to gracefully close the underlying HTTP
session on application shutdown. This change enables proper resource
management by allowing the client to be closed cleanly.

.github/scripts/check_sdk_methods.py

@@ -1,10 +1,15 @@
 import ast
 import os
 from itertools import filterfalse
-from typing import List, Tuple
+from typing import Dict, List, Tuple
 
 ROOT_PATH = os.path.abspath(os.path.join(__file__, "..", "..", ".."))
 CLIENT_PATH = os.path.join(ROOT_PATH, "libs", "sdk-py", "langgraph_sdk", "client.py")
+ASYNC_TO_SYNC_METHOD_MAP: Dict[str, str] = {
+    "aclose": "close",
+    "__aenter__": "__enter__",
+    "__aexit__": "__exit__",
+}
 
 
 def get_class_methods(node: ast.ClassDef) -> List[str]:
@@ -22,7 +27,7 @@ def find_classes(tree: ast.AST) -> List[Tuple[str, List[str]]]:
 
 def compare_sync_async_methods(sync_methods: List[str], async_methods: List[str]) -> List[str]:
     sync_set = set(sync_methods)
-    async_set = set(async_methods)
+    async_set = {ASYNC_TO_SYNC_METHOD_MAP.get(async_method, async_method) for async_method in async_methods}
     missing_in_sync = list(async_set - sync_set)
     missing_in_async = list(sync_set - async_set)
     return missing_in_sync + missing_in_async

libs/sdk-py/langgraph_sdk/client.py

@@ -16,6 +16,7 @@ import os
 import re
 import sys
 from collections.abc import AsyncIterator, Iterator, Sequence
+from types import TracebackType
 from typing import (
     Any,
     Callable,
@@ -236,6 +237,24 @@ class LangGraphClient:
         self.crons = CronClient(self.http)
         self.store = StoreClient(self.http)
 
+    async def __aenter__(self) -> LangGraphClient:
+        """Enter the async context manager."""
+        return self
+
+    async def __aexit__(
+        self,
+        exc_type: type[BaseException] | None,
+        exc_val: BaseException | None,
+        exc_tb: TracebackType | None,
+    ) -> None:
+        """Exit the async context manager."""
+        await self.aclose()
+
+    async def aclose(self) -> None:
+        """Close the underlying HTTP client."""
+        if hasattr(self, "http"):
+            await self.http.client.aclose()
+
 
 class HttpClient:
     """Handle async requests to the LangGraph API.
@@ -3212,6 +3231,24 @@ class SyncLangGraphClient:
         self.crons = SyncCronClient(self.http)
         self.store = SyncStoreClient(self.http)
 
+    def __enter__(self) -> SyncLangGraphClient:
+        """Enter the sync context manager."""
+        return self
+
+    def __exit__(
+        self,
+        exc_type: type[BaseException] | None,
+        exc_val: BaseException | None,
+        exc_tb: TracebackType | None,
+    ) -> None:
+        """Exit the sync context manager."""
+        self.close()
+
+    def close(self) -> None:
+        """Close the underlying HTTP client."""
+        if hasattr(self, "http"):
+            self.http.client.close()
+
 
 class SyncHttpClient:
     """Handle synchronous requests to the LangGraph API.