updates to allow new gui to recreate session to continue where it left off

daemon/core/api/grpc/client.py

@@ -262,6 +262,16 @@ class CoreGrpcClient:
         """
         return self.stub.GetSessions(core_pb2.GetSessionsRequest())
 
+    def check_session(self, session_id: int) -> core_pb2.CheckSessionResponse:
+        """
+        Check if a session exists.
+
+        :param session_id: id of session to check for
+        :return: response with result if session was found
+        """
+        request = core_pb2.CheckSessionRequest(session_id=session_id)
+        return self.stub.CheckSession(request)
+
     def get_session(self, session_id: int) -> core_pb2.GetSessionResponse:
         """
         Retrieve a session.

daemon/core/api/grpc/server.py

@@ -453,6 +453,19 @@ class CoreGrpcServer(core_pb2_grpc.CoreApiServicer):
         session.metadata = dict(request.config)
         return core_pb2.SetSessionMetadataResponse(result=True)
 
+    def CheckSession(
+        self, request: core_pb2.GetSessionRequest, context: ServicerContext
+    ) -> core_pb2.CheckSessionResponse:
+        """
+        Checks if a session exists.
+
+        :param request: check session request
+        :param context: context object
+        :return: check session response
+        """
+        result = request.session_id in self.coreemu.sessions
+        return core_pb2.CheckSessionResponse(result=result)
+
     def GetSession(
         self, request: core_pb2.GetSessionRequest, context: ServicerContext
     ) -> core_pb2.GetSessionResponse:

daemon/core/gui/coreclient.py

@@ -58,7 +58,7 @@ class CoreClient:
         """
         Create a CoreGrpc instance
         """
-        self.client = client.CoreGrpcClient(proxy=proxy)
+        self._client = client.CoreGrpcClient(proxy=proxy)
         self.session_id = None
         self.node_ids = []
         self.app = app
@@ -102,6 +102,22 @@ class CoreClient:
 
         self.modified_service_nodes = set()
 
+    @property
+    def client(self):
+        if self.session_id:
+            response = self._client.check_session(self.session_id)
+            if not response.result:
+                throughputs_enabled = self.handling_throughputs is not None
+                self.cancel_throughputs()
+                self.cancel_events()
+                self._client.create_session(self.session_id)
+                self.handling_events = self._client.events(
+                    self.session_id, self.handle_events
+                )
+                if throughputs_enabled:
+                    self.enable_throughputs()
+        return self._client
+
     def reset(self):
         # helpers
         self.interfaces_manager.reset()
@@ -121,12 +137,8 @@ class CoreClient:
             mobility_player.handle_close()
         self.mobility_players.clear()
         # clear streams
-        if self.handling_throughputs:
+        self.cancel_throughputs()
-            self.handling_throughputs.cancel()
+        self.cancel_events()
-            self.handling_throughputs = None
-        if self.handling_events:
-            self.handling_events.cancel()
-            self.handling_events = None
 
     def set_observer(self, value: str):
         self.observer = value
@@ -217,8 +229,14 @@ class CoreClient:
         )
 
     def cancel_throughputs(self):
-        self.handling_throughputs.cancel()
+        if self.handling_throughputs:
-        self.handling_throughputs = None
+            self.handling_throughputs.cancel()
+            self.handling_throughputs = None
+
+    def cancel_events(self):
+        if self.handling_events:
+            self.handling_events.cancel()
+            self.handling_events = None
 
     def handle_throughputs(self, event: core_pb2.ThroughputsEvent):
         if event.session_id != self.session_id:

daemon/proto/core/api/grpc/core.proto

@@ -22,6 +22,8 @@ service CoreApi {
     }
     rpc GetSession (GetSessionRequest) returns (GetSessionResponse) {
     }
+    rpc CheckSession (CheckSessionRequest) returns (CheckSessionResponse) {
+    }
     rpc GetSessionOptions (GetSessionOptionsRequest) returns (GetSessionOptionsResponse) {
     }
     rpc SetSessionOptions (SetSessionOptionsRequest) returns (SetSessionOptionsResponse) {
@@ -212,6 +214,14 @@ message GetSessionsResponse {
     repeated SessionSummary sessions = 1;
 }
 
+message CheckSessionRequest {
+    int32 session_id = 1;
+}
+
+message CheckSessionResponse {
+    bool result = 1;
+}
+
 message GetSessionRequest {
     int32 session_id = 1;
 }