Handle binary userdata files such as gzip

The current code in the servers api assumes only text files will be
provided as userdata. That is, the data is utf-8 encoded before it
is base64 encoded and sent. This breaks for binary userdata files,
(example, gzip files) as they can't be utf-8 encoded.

This change ignores specifically the exceptions that are raised
when utf-8 encoding is attempted on non-text data: AttributeError
and UnicodeDecodeError. These exceptions will be ignored to let
binary files proceed to the base64 encoding step.

Closes-Bug: #1419859

Change-Id: Ie96283f6ff892ae30485722cf7c3ec40f3f1b5df

novaclient/tests/unit/v2/test_servers.py

@@ -12,6 +12,10 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import base64
+import os
+import tempfile
+
 import mock
 from oslo.serialization import jsonutils
 import six
@@ -199,6 +203,32 @@ class ServersTest(utils.FixturedTestCase):
         self.assert_called('POST', '/servers')
         self.assertIsInstance(s, servers.Server)
 
+    def test_create_server_userdata_bin(self):
+        with tempfile.TemporaryFile(mode='wb+') as bin_file:
+            original_data = os.urandom(1024)
+            bin_file.write(original_data)
+            bin_file.flush()
+            bin_file.seek(0)
+            s = self.cs.servers.create(
+                name="My server",
+                image=1,
+                flavor=1,
+                meta={'foo': 'bar'},
+                userdata=bin_file,
+                key_name="fakekey",
+                files={
+                    '/etc/passwd': 'some data',                 # a file
+                    '/tmp/foo.txt': six.StringIO('data'),   # a stream
+                },
+            )
+            self.assert_called('POST', '/servers')
+            self.assertIsInstance(s, servers.Server)
+            # verify userdata matches original
+            body = jsonutils.loads(self.requests.last_request.body)
+            transferred_data = body['server']['user_data']
+            transferred_data = base64.b64decode(transferred_data)
+            self.assertEqual(original_data, transferred_data)
+
     def _create_disk_config(self, disk_config):
         s = self.cs.servers.create(
             name="My server",

novaclient/v2/servers.py

@@ -433,10 +433,19 @@ class ServerManager(base.BootingManagerWithFind):
             if hasattr(userdata, 'read'):
                 userdata = userdata.read()
 
+            # NOTE(melwitt): Text file data is converted to bytes prior to
+            # base64 encoding. The utf-8 encoding will fail for binary files.
             if six.PY3:
-                userdata = userdata.encode("utf-8")
+                try:
+                    userdata = userdata.encode("utf-8")
+                except AttributeError:
+                    # In python 3, 'bytes' object has no attribute 'encode'
+                    pass
             else:
-                userdata = encodeutils.safe_encode(userdata)
+                try:
+                    userdata = encodeutils.safe_encode(userdata)
+                except UnicodeDecodeError:
+                    pass
 
             userdata_b64 = base64.b64encode(userdata).decode('utf-8')
             body["server"]["user_data"] = userdata_b64