Add a ProxyKmipClient integation test for registering wrapped keys

This change adds a ProxyKmipClient integration test that verifies
that a wrapped key can be registered with the server and can then
be retrieved, along with all of its key wrapping metadata. Minor
updates to the underlying metadata handling are included.

kmip/tests/integration/services/test_proxykmipclient.py

@@ -128,6 +128,51 @@ class TestProxyKmipClientIntegration(testtools.TestCase):
             self.assertRaises(
                 exceptions.KmipOperationFailure, self.client.destroy, uid)
 
+    def test_register_wrapped_get_destroy(self):
+        """
+        Test that a wrapped key can be registered with the server and that its
+        metadata is retrieved with the get operation.
+        """
+        key = objects.SymmetricKey(
+            enums.CryptographicAlgorithm.AES,
+            128,
+            (b'\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0A\x0B\x0C\x0D\x0E'
+             b'\x0F'),
+            key_wrapping_data={
+                'wrapping_method': enums.WrappingMethod.ENCRYPT,
+                'encryption_key_information': {
+                    'unique_identifier': '42',
+                    'cryptographic_parameters': {
+                        'block_cipher_mode':
+                            enums.BlockCipherMode.NIST_KEY_WRAP
+                    }
+                },
+                'encoding_option': enums.EncodingOption.NO_ENCODING
+            }
+        )
+        key_id = self.client.register(key)
+
+        result = self.client.get(key_id)
+        key_wrapping_data = result.key_wrapping_data
+        self.assertIsInstance(key_wrapping_data, dict)
+        self.assertEqual(
+            enums.WrappingMethod.ENCRYPT,
+            key_wrapping_data.get('wrapping_method')
+        )
+        eki = key_wrapping_data.get('encryption_key_information')
+        self.assertIsInstance(eki, dict)
+        self.assertEqual('42', eki.get('unique_identifier'))
+        cp = eki.get('cryptographic_parameters')
+        self.assertIsInstance(cp, dict)
+        self.assertEqual(
+            enums.BlockCipherMode.NIST_KEY_WRAP,
+            cp.get('block_cipher_mode')
+        )
+        self.assertEqual(
+            enums.EncodingOption.NO_ENCODING,
+            key_wrapping_data.get('encoding_option')
+        )
+
     def test_asymmetric_key_pair_create_get_destroy(self):
         """
         Test that the ProxyKmipClient can create, retrieve, and destroy an