updated start proto to return exception strings, updated grpc start session to exist early when a failure is found, updated coretk ui to not switch ui to running when start fails and display error dialog

daemon/core/api/grpc/server.py

@@ -124,7 +124,10 @@ class CoreGrpcServer(core_pb2_grpc.CoreApiServicer):
             session.add_hook(hook.state, hook.file, None, hook.data)
 
         # create nodes
-        grpcutils.create_nodes(session, request.nodes)
+        _, exceptions = grpcutils.create_nodes(session, request.nodes)
+        if exceptions:
+            exceptions = [str(x) for x in exceptions]
+            return core_pb2.StartSessionResponse(result=False, exceptions=exceptions)
 
         # emane configs
         config = session.emane.get_configs()
@@ -156,14 +159,28 @@ class CoreGrpcServer(core_pb2_grpc.CoreApiServicer):
             )
 
         # create links
-        grpcutils.create_links(session, request.links)
+        _, exceptions = grpcutils.create_links(session, request.links)
+        if exceptions:
+            exceptions = [str(x) for x in exceptions]
+            return core_pb2.StartSessionResponse(result=False, exceptions=exceptions)
 
         # asymmetric links
-        grpcutils.edit_links(session, request.asymmetric_links)
+        _, exceptions = grpcutils.edit_links(session, request.asymmetric_links)
+        if exceptions:
+            exceptions = [str(x) for x in exceptions]
+            return core_pb2.StartSessionResponse(result=False, exceptions=exceptions)
 
         # set to instantiation and start
         session.set_state(EventTypes.INSTANTIATION_STATE)
-        session.instantiate()
+
+        # boot services
+        boot_exceptions = session.instantiate()
+        if boot_exceptions:
+            exceptions = []
+            for boot_exception in boot_exceptions:
+                for service_exception in boot_exception.args:
+                    exceptions.append(str(service_exception))
+            return core_pb2.StartSessionResponse(result=False, exceptions=exceptions)
 
         return core_pb2.StartSessionResponse(result=True)
 

daemon/core/emulator/session.py

@@ -635,7 +635,6 @@ class Session:
         :return: created node
         :raises core.CoreError: when an invalid node type is given
         """
-
         # validate node type, get class, or throw error
         if _cls is None:
             node_class = self.get_node_class(_type)
@@ -1450,17 +1449,19 @@ class Session:
             return
 
         # boot node services and then start mobility
-        self.boot_nodes()
+        exceptions = self.boot_nodes()
-        self.mobility.startup()
+        if not exceptions:
+            self.mobility.startup()
 
-        # notify listeners that instantiation is complete
+            # notify listeners that instantiation is complete
-        event = EventData(event_type=EventTypes.INSTANTIATION_COMPLETE.value)
+            event = EventData(event_type=EventTypes.INSTANTIATION_COMPLETE.value)
-        self.broadcast_event(event)
+            self.broadcast_event(event)
 
-        # assume either all nodes have booted already, or there are some
+            # assume either all nodes have booted already, or there are some
-        # nodes on slave servers that will be booted and those servers will
+            # nodes on slave servers that will be booted and those servers will
-        # send a node status response message
+            # send a node status response message
-        self.check_runtime()
+            self.check_runtime()
+        return exceptions
 
     def get_node_count(self):
         """
@@ -1577,6 +1578,9 @@ class Session:
         Invoke the boot() procedure for all nodes and send back node
         messages to the GUI for node messages that had the status
         request flag.
+
+        :return: service boot exceptions
+        :rtype: list[core.services.coreservices.ServiceBootError]
         """
         with self._nodes_lock:
             funcs = []
@@ -1589,9 +1593,9 @@ class Session:
             results, exceptions = utils.threadpool(funcs)
             total = time.monotonic() - start
             logging.debug("boot run time: %s", total)
-            if exceptions:
+        if not exceptions:
-                raise CoreError(exceptions)
+            self.update_control_interface_hosts()
-        self.update_control_interface_hosts()
+        return exceptions
 
     def get_control_net_prefixes(self):
         """

daemon/core/gui/coreclient.py

@@ -6,6 +6,7 @@ import logging
 import os
 import time
 from pathlib import Path
+from tkinter import messagebox
 
 import grpc
 
@@ -476,21 +477,31 @@ class CoreClient:
                 file_configs,
                 asymmetric_links,
             )
-            self.set_metadata()
-            process_time = time.perf_counter() - start
             logging.debug(
                 "start session(%s), result: %s", self.session_id, response.result
             )
-            self.app.statusbar.start_session_callback(process_time)
+            process_time = time.perf_counter() - start
 
-            # display mobility players
+            # stop progress bar and update status
-            for node_id, config in self.mobility_configs.items():
+            self.app.statusbar.progress_bar.stop()
-                canvas_node = self.canvas_nodes[node_id]
+            message = f"Start ran for {process_time:.3f} seconds"
-                mobility_player = MobilityPlayer(
+            self.app.statusbar.set_status(message)
-                    self.app, self.app, canvas_node, config
+
-                )
+            if response.result:
-                mobility_player.show()
+                self.set_metadata()
-                self.mobility_players[node_id] = mobility_player
+                self.app.toolbar.set_runtime()
+
+                # display mobility players
+                for node_id, config in self.mobility_configs.items():
+                    canvas_node = self.canvas_nodes[node_id]
+                    mobility_player = MobilityPlayer(
+                        self.app, self.app, canvas_node, config
+                    )
+                    mobility_player.show()
+                    self.mobility_players[node_id] = mobility_player
+            else:
+                message = "\n".join(response.exceptions)
+                messagebox.showerror("Start Error", message)
         except grpc.RpcError as e:
             show_grpc_error(e)
 

daemon/core/gui/statusbar.py

@@ -68,10 +68,9 @@ class StatusBar(ttk.Frame):
         dialog = AlertsDialog(self.app, self.app)
         dialog.show()
 
-    def start_session_callback(self, process_time):
+    def set_status(self, message):
-        self.progress_bar.stop()
+        self.statusvar.set(message)
-        self.statusvar.set(f"Session started in {process_time:.3f} seconds")
 
     def stop_session_callback(self, cleanup_time):
         self.progress_bar.stop()
-        self.statusvar.set(f"Stopped session in {cleanup_time:.3f} seconds")
+        self.statusvar.set(f"Stopped in {cleanup_time:.3f} seconds")

daemon/core/gui/toolbar.py

@@ -236,11 +236,12 @@ class Toolbar(ttk.Frame):
         :return: nothing
         """
         self.app.canvas.hide_context()
-        self.app.statusbar.core_alarms.clear()
         self.app.statusbar.progress_bar.start(5)
         self.app.canvas.mode = GraphMode.SELECT
         thread = threading.Thread(target=self.app.core.start_session)
         thread.start()
+
+    def set_runtime(self):
         self.runtime_frame.tkraise()
         self.click_runtime_selection()
 

daemon/core/services/coreservices.py

@@ -458,7 +458,7 @@ class CoreServices:
         """
         Start all services on a node.
 
-        :param core.netns.vnode.LxcNode node: node to start services on
+        :param core.nodes.base.CoreNode node: node to start services on
         :return: nothing
         """
         boot_paths = ServiceDependencies(node.services).boot_paths()
@@ -468,7 +468,7 @@ class CoreServices:
             funcs.append((self._start_boot_paths, args, {}))
         result, exceptions = utils.threadpool(funcs)
         if exceptions:
-            raise ServiceBootError(exceptions)
+            raise ServiceBootError(*exceptions)
 
     def _start_boot_paths(self, node, boot_path):
         """

daemon/core/services/utility.py

@@ -8,7 +8,7 @@ from core import constants, utils
 from core.errors import CoreCommandError
 from core.nodes import ipaddress
 from core.nodes.ipaddress import Ipv4Prefix, Ipv6Prefix
-from core.services.coreservices import CoreService
+from core.services.coreservices import CoreService, ServiceMode
 
 
 class UtilService(CoreService):
@@ -173,6 +173,7 @@ class SshService(UtilService):
     startup = ("sh startsshd.sh",)
     shutdown = ("killall sshd",)
     validate = ()
+    validation_mode = ServiceMode.BLOCKING
 
     @classmethod
     def generate_config(cls, node, filename):

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

@@ -155,6 +155,7 @@ message StartSessionRequest {
 
 message StartSessionResponse {
     bool result = 1;
+    repeated string exceptions = 2;
 }
 
 message StopSessionRequest {