Impl remove and get subscription APIs for python xlang (#5365)

Closes #5297

---------

Co-authored-by: Ryan Sweet <rysweet@microsoft.com>
Co-authored-by: Jacob Alber <jaalber@microsoft.com>
Co-authored-by: Jacob Alber <jacob.alber@microsoft.com>
Co-authored-by: Eric Zhu <ekzhu@users.noreply.github.com>

python/packages/autogen-core/src/autogen_core/_runtime_impl_helpers.py

@@ -1,5 +1,5 @@
 from collections import defaultdict
-from typing import Awaitable, Callable, DefaultDict, List, Set
+from typing import Awaitable, Callable, DefaultDict, List, Set, Sequence
 
 from ._agent import Agent
 from ._agent_id import AgentId
@@ -35,6 +35,10 @@ class SubscriptionManager:
         self._seen_topics: Set[TopicId] = set()
         self._subscribed_recipients: DefaultDict[TopicId, List[AgentId]] = defaultdict(list)
 
+    @property
+    def subscriptions(self) -> Sequence[Subscription]:
+        return self._subscriptions
+
     async def add_subscription(self, subscription: Subscription) -> None:
         # Check if the subscription already exists
         if any(sub == subscription for sub in self._subscriptions):

python/packages/autogen-ext/src/autogen_ext/runtimes/grpc/_worker_runtime.py

@@ -790,7 +790,15 @@ class GrpcWorkerAgentRuntime(AgentRuntime):
         await self._subscription_manager.add_subscription(subscription)
 
     async def remove_subscription(self, id: str) -> None:
-        raise NotImplementedError("Subscriptions cannot be removed while using distributed runtime currently.")
+        if self._host_connection is None:
+            raise RuntimeError("Host connection is not set.")
+
+        message = agent_worker_pb2.RemoveSubscriptionRequest(id=id)
+        _response: agent_worker_pb2.RemoveSubscriptionResponse = await self._host_connection.stub.RemoveSubscription(
+            message, metadata=self._host_connection.metadata
+        )
+
+        await self._subscription_manager.remove_subscription(id)
 
     async def get(
         self, id_or_type: AgentId | AgentType | str, /, key: str = "default", *, lazy: bool = True

python/packages/autogen-ext/src/autogen_ext/runtimes/grpc/_worker_runtime_host_servicer.py

@@ -11,7 +11,7 @@ from autogen_core._agent_id import AgentId
 from autogen_core._runtime_impl_helpers import SubscriptionManager
 
 from ._constants import GRPC_IMPORT_ERROR_STR
-from ._utils import subscription_from_proto
+from ._utils import subscription_from_proto, subscription_to_proto
 
 try:
     import grpc
@@ -170,7 +170,11 @@ class GrpcWorkerAgentRuntimeHostServicer(agent_worker_pb2_grpc.AgentRpcServicer)
                 del self._agent_type_to_client_id[agent_type]
             for sub_id in self._client_id_to_subscription_id_mapping.get(client_id, set()):
                 logger.info(f"Client id {client_id} disconnected. Removing corresponding subscription with id {id}")
-                await self._subscription_manager.remove_subscription(sub_id)
+                try:
+                    await self._subscription_manager.remove_subscription(sub_id)
+                # Catch and ignore if the subscription does not exist.
+                except ValueError:
+                    continue
         logger.info(f"Client {client_id} disconnected successfully")
 
     def _raise_on_exception(self, task: Task[Any]) -> None:
@@ -327,7 +331,8 @@ class GrpcWorkerAgentRuntimeHostServicer(agent_worker_pb2_grpc.AgentRpcServicer)
         ],
     ) -> agent_worker_pb2.RemoveSubscriptionResponse:
         _client_id = await get_client_id_or_abort(context)
-        raise NotImplementedError("Method not implemented.")
+        await self._subscription_manager.remove_subscription(request.id)
+        return agent_worker_pb2.RemoveSubscriptionResponse()
 
     async def GetSubscriptions(  # type: ignore
         self,
@@ -337,4 +342,23 @@ class GrpcWorkerAgentRuntimeHostServicer(agent_worker_pb2_grpc.AgentRpcServicer)
         ],
     ) -> agent_worker_pb2.GetSubscriptionsResponse:
         _client_id = await get_client_id_or_abort(context)
-        raise NotImplementedError("Method not implemented.")
+        subscriptions = self._subscription_manager.subscriptions
+        return agent_worker_pb2.GetSubscriptionsResponse(
+            subscriptions=[subscription_to_proto(sub) for sub in subscriptions]
+        )
+
+    # async def GetState(  # type: ignore
+    #     self,
+    #     request: agent_worker_pb2.AgentId,
+    #     context: grpc.aio.ServicerContext[agent_worker_pb2.AgentId, agent_worker_pb2.GetStateResponse],
+    # ) -> agent_worker_pb2.GetStateResponse:
+    #     _client_id = await get_client_id_or_abort(context)
+    #     raise NotImplementedError("Method not implemented!")
+
+    # async def SaveState(  # type: ignore
+    #     self,
+    #     request: agent_worker_pb2.AgentState,
+    #     context: grpc.aio.ServicerContext[agent_worker_pb2.AgentId, agent_worker_pb2.SaveStateResponse],
+    # ) -> agent_worker_pb2.SaveStateResponse:
+    #     _client_id = await get_client_id_or_abort(context)
+    #     raise NotImplementedError("Method not implemented!")

python/packages/autogen-ext/tests/test_worker_runtime.py

@@ -8,6 +8,7 @@ from autogen_core import (
     PROTOBUF_DATA_CONTENT_TYPE,
     AgentId,
     AgentType,
+    DefaultSubscription,
     DefaultTopicId,
     MessageContext,
     RoutedAgent,
@@ -129,6 +130,47 @@ async def test_register_receives_publish() -> None:
 
 
 @pytest.mark.grpc
+@pytest.mark.asyncio
+async def test_register_doesnt_receive_after_removing_subscription() -> None:
+    host_address = "localhost:50053"
+    host = GrpcWorkerAgentRuntimeHost(address=host_address)
+    host.start()
+
+    worker1 = GrpcWorkerAgentRuntime(host_address=host_address)
+    worker1.start()
+    worker1.add_message_serializer(try_get_known_serializers_for_type(MessageType))
+    await worker1.register_factory(
+        type=AgentType("name1"), agent_factory=lambda: LoopbackAgent(), expected_class=LoopbackAgent
+    )
+    sub = DefaultSubscription(agent_type="name1")
+    await worker1.add_subscription(sub)
+
+    agent_1_instance = await worker1.try_get_underlying_agent_instance(AgentId("name1", "default"), LoopbackAgent)
+    # Publish message from worker1
+    await worker1.publish_message(MessageType(), topic_id=DefaultTopicId())
+
+    # Let the agent run for a bit.
+    await agent_1_instance.event.wait()
+    agent_1_instance.event.clear()
+
+    # Agents in default topic source should have received the message.
+    assert agent_1_instance.num_calls == 1
+
+    await worker1.remove_subscription(sub.id)
+
+    # Publish message from worker1
+    await worker1.publish_message(MessageType(), topic_id=DefaultTopicId())
+
+    # Let the agent run for a bit.
+    await asyncio.sleep(2)
+
+    # Agent should not have received the message.
+    assert agent_1_instance.num_calls == 1
+
+    await worker1.stop()
+    await host.stop()
+
+
 @pytest.mark.asyncio
 async def test_register_receives_publish_cascade_single_worker() -> None:
     host_address = "localhost:50054"

python/packages/autogen-test-utils/src/autogen_test_utils/__init__.py

@@ -16,6 +16,8 @@ from autogen_core import (
 )
 from pydantic import BaseModel
 
+from asyncio import Event
+
 
 @dataclass
 class MessageType: ...
@@ -36,6 +38,7 @@ class LoopbackAgent(RoutedAgent):
         super().__init__("A loop back agent.")
         self.num_calls = 0
         self.received_messages: list[Any] = []
+        self.event = Event()
 
     @message_handler
     async def on_new_message(
@@ -43,6 +46,7 @@ class LoopbackAgent(RoutedAgent):
     ) -> MessageType | ContentMessage:
         self.num_calls += 1
         self.received_messages.append(message)
+        self.event.set()
         return message