DataSourceOVF: fix user-data as base64 with python3

When user-data was provided in the ovf environment python3 would call
base64.decodestring() with a string rather than bytes and an exception
would occur.

This fixes the broken path and adds unit test.  Also changes to
return None rather than empty string when there is no user-data and
when there is user-data return that as bytes instead of string.

LP: #1619394

2 files changed, 87 insertions, 4 deletions

diff --git a/cloudinit/sources/DataSourceOVF.py b/cloudinit/sources/DataSourceOVF.py
index 43347cfb..5b3bdb4e 100644
--- a/cloudinit/sources/DataSourceOVF.py
+++ b/cloudinit/sources/DataSourceOVF.py
@@ -237,7 +237,7 @@ def wait_for_imc_cfg_file(dirpath, filename, maxwait=180, naplen=5):
 def read_vmware_imc(config):
     md = {}
     cfg = {}
-    ud = ""
+    ud = None
     if config.host_name:
         if config.domain_name:
             md['local-hostname'] = config.host_name + "." + config.domain_name
@@ -256,7 +256,7 @@ def read_ovf_environment(contents):
     props = get_properties(contents)
     md = {}
     cfg = {}
-    ud = ""
+    ud = None
     cfg_props = ['password']
     md_props = ['seedfrom', 'local-hostname', 'public-keys', 'instance-id']
     for (prop, val) in props.items():
@@ -268,9 +268,9 @@ def read_ovf_environment(contents):
             cfg[prop] = val
         elif prop == "user-data":
             try:
-                ud = base64.decodestring(val)
+                ud = base64.b64decode(val.encode())
             except Exception:
-                ud = val
+                ud = val.encode()
     return (md, ud, cfg)
 
 
diff --git a/tests/unittests/test_datasource/test_ovf.py b/tests/unittests/test_datasource/test_ovf.py
new file mode 100644
index 00000000..5f8e7e44
--- /dev/null
+++ b/tests/unittests/test_datasource/test_ovf.py
@@ -0,0 +1,83 @@
+# vi: ts=4 expandtab
+#
+#    Copyright (C) 2016 Canonical Ltd.
+#
+#    Author: Scott Moser <scott.moser@canonical.com>
+#
+#    This program is free software: you can redistribute it and/or modify
+#    it under the terms of the GNU General Public License version 3, as
+#    published by the Free Software Foundation.
+#
+#    This program is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    GNU General Public License for more details.
+#
+#    You should have received a copy of the GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import base64
+
+from .. import helpers as test_helpers
+
+from cloudinit.sources import DataSourceOVF as dsovf
+
+OVF_ENV_CONTENT = """<?xml version="1.0" encoding="UTF-8"?>
+<Environment xmlns="http://schemas.dmtf.org/ovf/environment/1"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xmlns:oe="http://schemas.dmtf.org/ovf/environment/1"
+  xsi:schemaLocation="http://schemas.dmtf.org/ovf/environment/1 ../dsp8027.xsd"
+  oe:id="WebTier">
+  <!-- Information about hypervisor platform -->
+  <oe:PlatformSection>
+      <Kind>ESX Server</Kind>
+      <Version>3.0.1</Version>
+      <Vendor>VMware, Inc.</Vendor>
+      <Locale>en_US</Locale>
+  </oe:PlatformSection>
+  <!--- Properties defined for this virtual machine -->
+  <PropertySection>
+{properties}
+  </PropertySection>
+</Environment>
+"""
+
+
+def fill_properties(props, template=OVF_ENV_CONTENT):
+    lines = []
+    prop_tmpl = '<Property oe:key="{key}" oe:value="{val}"/>'
+    for key, val in props.items():
+        lines.append(prop_tmpl.format(key=key, val=val))
+    indent = "        "
+    properties = ''.join([indent + l + "\n" for l in lines])
+    return template.format(properties=properties)
+
+
+class TestReadOvfEnv(test_helpers.TestCase):
+    def test_with_b64_userdata(self):
+        user_data = "#!/bin/sh\necho hello world\n"
+        user_data_b64 = base64.b64encode(user_data.encode()).decode()
+        props = {"user-data": user_data_b64, "password": "passw0rd",
+                 "instance-id": "inst-001"}
+        env = fill_properties(props)
+        md, ud, cfg = dsovf.read_ovf_environment(env)
+        self.assertEqual({"instance-id": "inst-001"}, md)
+        self.assertEqual(user_data.encode(), ud)
+        self.assertEqual({'password': "passw0rd"}, cfg)
+
+    def test_with_non_b64_userdata(self):
+        user_data = "my-user-data"
+        props = {"user-data": user_data, "instance-id": "inst-001"}
+        env = fill_properties(props)
+        md, ud, cfg = dsovf.read_ovf_environment(env)
+        self.assertEqual({"instance-id": "inst-001"}, md)
+        self.assertEqual(user_data.encode(), ud)
+        self.assertEqual({}, cfg)
+
+    def test_with_no_userdata(self):
+        props = {"password": "passw0rd", "instance-id": "inst-001"}
+        env = fill_properties(props)
+        md, ud, cfg = dsovf.read_ovf_environment(env)
+        self.assertEqual({"instance-id": "inst-001"}, md)
+        self.assertEqual({'password': "passw0rd"}, cfg)
+        self.assertEqual(None, ud)