Use no user when the especified user is not found in the users section

Author: Sergi Almacellas Abellana

config/kube_config.py

@@ -132,8 +132,12 @@ def set_active_context(self, context_name=None):
             context_name)
         if (self._current_context['context'].safe_get('user')
                 and self._config.safe_get('users')):
-            self._user = self._config['users'].get_with_name(
-                self._current_context['context']['user'])['user']
+            user = self._config['users'].get_with_name(
+                self._current_context['context']['user'], safe=True)
+            if user:
+                self._user = user['user']
+            else:
+                self._user = None
         else:
             self._user = None
         self._cluster = self._config['clusters'].get_with_name(
@@ -257,7 +261,7 @@ def __getitem__(self, key):
         else:
             return v
 
-    def get_with_name(self, name):
+    def get_with_name(self, name, safe=False):
         if not isinstance(self.value, list):
             raise ConfigException(
                 'Invalid kube-config file. Expected %s to be a list'
@@ -270,6 +274,8 @@ def get_with_name(self, name):
                     % self.name)
             if v['name'] == name:
                 return ConfigNode('%s[name=%s]' % (self.name, name), v)
+        if safe:
+            return None
         raise ConfigException(
             'Invalid kube-config file. '
             'Expected object with name %s in %s list' % (name, self.name))

config/kube_config_test.py

@@ -339,6 +339,13 @@ class TestKubeConfigLoader(BaseTestCase):
                     "user": "ssl-local-file"
                 }
             },
+            {
+                "name": "non_existing_user",
+                "context": {
+                    "cluster": "default",
+                    "user": "non_existing_user"
+                }
+            },
         ],
         "clusters": [
             {
@@ -626,6 +633,15 @@ def test_no_users_section(self):
             client_configuration=actual).load_and_set()
         self.assertEqual(expected, actual)
 
+    def test_non_existing_user(self):
+        expected = FakeConfig(host=TEST_HOST)
+        actual = FakeConfig()
+        KubeConfigLoader(
+            config_dict=self.TEST_KUBE_CONFIG,
+            active_context="non_existing_user",
+            client_configuration=actual).load_and_set()
+        self.assertEqual(expected, actual)
+
 
 if __name__ == '__main__':
     unittest.main()