Fix stacktrace when exiting with Ctrl + C

Fix #547

gns3server/controller/__init__.py

@@ -125,10 +125,17 @@ class Controller:
         :param compute_id: Compute server identifier
         """
         compute = self.get_compute(compute_id)
+        yield from compute.close()
         del self._computes[compute_id]
         self.save()
         self.notification.emit("compute.deleted", compute.__json__())
 
+    @asyncio.coroutine
+    def close(self):
+        log.info("Close controller")
+        for compute in self._computes.values():
+            yield from compute.close()
+
     @property
     def notification(self):
         """

gns3server/controller/compute.py

@@ -93,6 +93,11 @@ class Compute:
         self._connected = False
         self._controller.notification.emit("compute.updated", self.__json__())
 
+    @asyncio.coroutine
+    def close(self):
+        self._connected = False
+        self._session.close()
+
     @property
     def version(self):
         """

gns3server/web/web_server.py

@@ -91,6 +91,9 @@ class WebServer:
             yield from self._handler.finish_connections()
             self._handler = None
 
+        if Config.instance().get_section_config("Server").getboolean("controller"):
+            yield from Controller.instance().close()
+
         for module in MODULES:
             log.debug("Unloading module {}".format(module.__name__))
             m = module.instance()
@@ -182,6 +185,7 @@ class WebServer:
             # Add a periodic callback to give a chance to process signals on Windows
             # because asyncio.add_signal_handler() is not supported yet on that platform
             # otherwise the loop runs outside of signal module's ability to trap signals.
+
             def wakeup():
                 loop.call_later(0.5, wakeup)
             loop.call_later(0.5, wakeup)
@@ -189,7 +193,6 @@ class WebServer:
 
         server_config = Config.instance().get_section_config("Server")
 
-
         ssl_context = None
         if server_config.getboolean("ssl"):
             if sys.platform.startswith("win"):