Add Delete Session Method (#5193)

langchain/client/langchain.py

@@ -200,7 +200,7 @@ class LangChainPlusClient(BaseSettings):
         return Dataset(**result)
 
     @retry(stop=stop_after_attempt(3), wait=wait_fixed(0.5))
-    def read_run(self, run_id: str) -> Run:
+    def read_run(self, run_id: Union[str, UUID]) -> Run:
         """Read a run from the LangChain+ API."""
         response = self._get(f"/runs/{run_id}")
         raise_for_status_with_text(response)
@@ -268,6 +268,22 @@ class LangChainPlusClient(BaseSettings):
         raise_for_status_with_text(response)
         yield from [TracerSession(**session) for session in response.json()]
 
+    @xor_args(("session_name", "session_id"))
+    def delete_session(
+        self, *, session_name: Optional[str] = None, session_id: Optional[str] = None
+    ) -> None:
+        """Delete a session from the LangChain+ API."""
+        if session_name is not None:
+            session_id = self.read_session(session_name=session_name).id
+        elif session_id is None:
+            raise ValueError("Must provide session_name or session_id")
+        response = requests.delete(
+            self.api_url + f"/sessions/{session_id}",
+            headers=self._headers,
+        )
+        raise_for_status_with_text(response)
+        return None
+
     def create_dataset(self, dataset_name: str, description: str) -> Dataset:
         """Create a dataset in the LangChain+ API."""
         dataset = DatasetCreate(
@@ -360,7 +376,7 @@ class LangChainPlusClient(BaseSettings):
         return Example(**result)
 
     @retry(stop=stop_after_attempt(3), wait=wait_fixed(0.5))
-    def read_example(self, example_id: str) -> Example:
+    def read_example(self, example_id: Union[str, UUID]) -> Example:
         """Read an example from the LangChain+ API."""
         response = self._get(f"/examples/{example_id}")
         raise_for_status_with_text(response)

tests/integration_tests/client/test_client.py

@@ -0,0 +1,52 @@
+"""LangChain+ langchain_client Integration Tests."""
+from uuid import uuid4
+
+import pytest
+from tenacity import RetryError
+
+from langchain.callbacks.manager import tracing_v2_enabled
+from langchain.client import LangChainPlusClient
+from langchain.tools.base import tool
+
+
+@pytest.fixture
+def langchain_client(monkeypatch: pytest.MonkeyPatch) -> LangChainPlusClient:
+    monkeypatch.setenv("LANGCHAIN_ENDPOINT", "http://localhost:1984")
+    return LangChainPlusClient()
+
+
+def test_sessions(
+    langchain_client: LangChainPlusClient, monkeypatch: pytest.MonkeyPatch
+) -> None:
+    """Test sessions."""
+    session_names = set([session.name for session in langchain_client.list_sessions()])
+    new_session = f"Session {uuid4()}"
+    assert new_session not in session_names
+
+    @tool
+    def example_tool() -> str:
+        """Call me, maybe."""
+        return "test_tool"
+
+    monkeypatch.setenv("LANGCHAIN_ENDPOINT", "http://localhost:1984")
+    with tracing_v2_enabled(session_name=new_session):
+        example_tool({})
+    session = langchain_client.read_session(session_name=new_session)
+    assert session.name == new_session
+    session_names = set([sess.name for sess in langchain_client.list_sessions()])
+    assert new_session in session_names
+    runs = list(langchain_client.list_runs(session_name=new_session))
+    session_id_runs = list(langchain_client.list_runs(session_id=session.id))
+    assert len(runs) == len(session_id_runs) == 1
+    assert runs[0].id == session_id_runs[0].id
+    langchain_client.delete_session(session_name=new_session)
+
+    with pytest.raises(RetryError):
+        langchain_client.read_session(session_name=new_session)
+    assert new_session not in set(
+        [sess.name for sess in langchain_client.list_sessions()]
+    )
+    with pytest.raises(RetryError):
+        langchain_client.delete_session(session_name=new_session)
+    with pytest.raises(RetryError):
+        langchain_client.read_run(run_id=str(runs[0].id))