Catch NeutronClientException when showing a network

When a network id can't be found, neutronclient raise
NetworkNotFoundClient exception, but this exception is not
handled by nova. This will cause a 500 error.
This patch fixes this bug.

Closes-Bug: #1286969
Change-Id: Ia96c9668c74374476d4dccdbdb281e99d91b0088

nova/network/neutronv2/api.py

@@ -829,7 +829,10 @@ class API(base_api.NetworkAPI):
     def get(self, context, network_uuid):
         """Get specific network for client."""
         client = neutronv2.get_client(context)
-        network = client.show_network(network_uuid).get('network') or {}
+        try:
+            network = client.show_network(network_uuid).get('network') or {}
+        except neutron_client_exc.NetworkNotFoundClient:
+            raise exception.NetworkNotFound(network_id=network_uuid)
         network['label'] = network['name']
         return network
 

nova/tests/network/test_neutronv2.py

@@ -2369,6 +2369,19 @@ class TestNeutronv2WithMock(test.TestCase):
         # Assert the calls.
         create_port_mock.assert_called_once_with(port_req_body)
 
+    def test_get_network_detail_not_found(self):
+        api = neutronapi.API()
+        expected_exc = exceptions.NetworkNotFoundClient()
+        network_uuid = '02cacbca-7d48-4a2c-8011-43eecf8a9786'
+        with mock.patch.object(client.Client, 'show_network',
+                               side_effect=expected_exc) as (
+            fake_show_network):
+            self.assertRaises(exception.NetworkNotFound,
+                              api.get,
+                              self.context,
+                              network_uuid)
+            fake_show_network.assert_called_once_with(network_uuid)
+
 
 class TestNeutronv2ModuleMethods(test.TestCase):