feat: Update Langgraph dependency to v1

pyproject.toml

@@ -48,7 +48,7 @@ test = [
     "pytest==8.4.2",
     "pytest-cov==7.0.0",
     "langchain-tests==1.1.0",
-    "langgraph==0.6.10"
+    "langgraph==1.0.4"
 ]
 
 [build-system]

requirements.txt

@@ -1,5 +1,5 @@
 cloud-sql-python-connector[asyncpg]==1.18.5
 numpy==2.3.3; python_version >= "3.11"
 numpy==2.2.6; python_version == "3.10"
-langgraph==0.6.10
+langgraph==1.0.4
 langchain-postgres==0.0.16

src/langchain_google_cloud_sql_pg/async_checkpoint.py

@@ -276,7 +276,9 @@ async def aput(
 
         async with self.pool.connect() as conn:
             type_, serialized_checkpoint = self.serde.dumps_typed(checkpoint)
-            serialized_metadata = self.jsonplus_serde.dumps(metadata)
+            serialized_metadata = json.dumps(metadata, ensure_ascii=False).encode(
+                "utf-8", "ignore"
+            )
             await conn.execute(
                 text(query),
                 {
@@ -409,7 +411,7 @@ async def alist(
                         (value["type"], value["checkpoint"])
                     ),
                     metadata=(
-                        self.jsonplus_serde.loads(value["metadata"])  # type: ignore
+                        json.loads(value["metadata"])  # type: ignore
                         if value["metadata"] is not None
                         else {}
                     ),
@@ -494,7 +496,7 @@ async def aget_tuple(self, config: RunnableConfig) -> Optional[CheckpointTuple]:
                 },
                 checkpoint=self.serde.loads_typed((value["type"], value["checkpoint"])),
                 metadata=(
-                    self.jsonplus_serde.loads(value["metadata"])  # type: ignore
+                    json.loads(value["metadata"])  # type: ignore
                     if value["metadata"] is not None
                     else {}
                 ),