console: introduce a new exception InvalidToken

Introduces a new exception InvalidToken used when an effectively
invalid token has be sent to a console proxy.
Updates the code to take advantage of this new one.

Change-Id: I9eb18541847e0ce22d5a449268876043ed8eb3a1

nova/console/websocketproxy.py

@@ -26,6 +26,7 @@ import websockify
 
 from nova.consoleauth import rpcapi as consoleauth_rpcapi
 from nova import context
+from nova import exception
 from nova.i18n import _
 from nova.openstack.common import log as logging
 
@@ -60,7 +61,7 @@ class NovaProxyRequestHandlerBase(object):
         connect_info = rpcapi.check_token(ctxt, token=token)
 
         if not connect_info:
-            raise Exception(_("Invalid Token"))
+            raise exception.InvalidToken(token=token)
 
         self.msg(_('connect info: %s'), str(connect_info))
         host = connect_info['host']

nova/exception.py

@@ -1754,3 +1754,7 @@ class InvalidHypervisorVirtType(Invalid):
 
 class InvalidVirtualMachineMode(Invalid):
     msg_fmt = _("Virtual machine mode '%(vmmode)s' is not recognised")
+
+
+class InvalidToken(Invalid):
+    msg_fmt = _("The token '%(token)s' is invalid or has expired")

nova/tests/console/test_websocketproxy.py

@@ -18,6 +18,7 @@
 import mock
 
 from nova.console import websocketproxy
+from nova import exception
 from nova import test
 
 
@@ -53,7 +54,8 @@ class NovaProxyRequestHandlerBaseTestCase(test.TestCase):
 
         self.wh.path = "ws://127.0.0.1/?token=XXX"
 
-        self.assertRaises(Exception, self.wh.new_websocket_client)  # noqa
+        self.assertRaises(exception.InvalidToken,
+                          self.wh.new_websocket_client)
         check_token.assert_called_with(mock.ANY, token="XXX")
 
     @mock.patch('nova.consoleauth.rpcapi.ConsoleAuthAPI.check_token')
@@ -79,5 +81,6 @@ class NovaProxyRequestHandlerBaseTestCase(test.TestCase):
         self.wh.path = "http://127.0.0.1/"
         self.wh.headers.getheader.return_value = "token=XXX"
 
-        self.assertRaises(Exception, self.wh.new_websocket_client)  # noqa
+        self.assertRaises(exception.InvalidToken,
+                          self.wh.new_websocket_client)
         check_token.assert_called_with(mock.ANY, token="XXX")