Server Failover Feature

This feature enables the PyKMIP library to switch between KMIP service provider
hosts in the event one of them is unavailable. To list more than than one host,
include all necessary host IP addresses separated by commas in the "host" field
in the pykmip.conf file.

Signed-off-by: Hadi Esiely <hadi.esiely-barrera@jhuapl.edu>

kmip/tests/unit/services/test_kmip_client.py

@@ -61,6 +61,10 @@ from kmip.services.results import RekeyKeyPairResult
 
 import kmip.core.utils as utils
 
+import mock
+
+import socket
+
 
 class TestKMIPClient(TestCase):
 
@@ -501,6 +505,62 @@ class TestKMIPClient(TestCase):
         self.assertEqual(uid, result.uid)
         self.assertEqual(names, result.names)
 
+    def test_host_list_import_string(self):
+        """
+        This test verifies that the client can process a string with
+        multiple IP addresses specified in it. It also tests that
+        unnecessary spaces are ignored.
+        """
+
+        host_list_string = '127.0.0.1,127.0.0.3,  127.0.0.5'
+        host_list_expected = ['127.0.0.1', '127.0.0.3', '127.0.0.5']
+
+        self.client._set_variables(host=host_list_string,
+                                   port=None, keyfile=None, certfile=None,
+                                   cert_reqs=None, ssl_version=None,
+                                   ca_certs=None,
+                                   do_handshake_on_connect=False,
+                                   suppress_ragged_eofs=None, username=None,
+                                   password=None, timeout=None)
+        self.assertEqual(host_list_expected, self.client.host_list)
+
+    def test_host_is_invalid_input(self):
+        """
+        This test verifies that invalid values are not processed when
+        setting the client object parameters
+        """
+        host = 1337
+        expected_error = TypeError
+
+        kwargs = {'host': host, 'port': None, 'keyfile': None,
+                  'certfile': None, 'cert_reqs': None, 'ssl_version': None,
+                  'ca_certs': None, 'do_handshake_on_connect': False,
+                  'suppress_ragged_eofs': None, 'username': None,
+                  'password': None, 'timeout': None}
+
+        self.assertRaises(expected_error, self.client._set_variables,
+                          **kwargs)
+
+    @mock.patch('socket.socket.connect')
+    @mock.patch('ssl.SSLSocket.gettimeout')
+    def test_timeout_all_hosts(self, mock_ssl_timeout, mock_connect_return):
+        """
+        This test verifies that the client will throw an exception if no
+        hosts are available for connection.
+        """
+
+        mock_ssl_timeout.return_value = 1
+        mock_connect_return.return_value = socket.timeout
+        try:
+            self.client.open()
+        except Exception as e:
+            # TODO: once the exception is properly defined in the
+            # kmip_client.py file this test needs to change to reflect that.
+            self.assertIsInstance(e, Exception)
+            self.client.close()
+        else:
+            self.client.close()
+
 
 class TestClientProfileInformation(TestCase):
     """