OpenNebula: support base64 encoded user-data

This change adds the possibility to have base64 encoded userdata in
OpenNebula source.

OpenNebula uses a text file with shell variables for storing the
configuration variables (including user provided data). Some user data may
not be renderable into this format, so using base64 encoding alleviates
the problem.

The change here allows the user to provide a second variable
USERDATA_ENCODING (or USER_DATA_ENCODING) and set that value to 'base64'
to indicate that USERDATA is base64 encoded.

3 files changed, 39 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 2d89d30d..7e2b761e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -39,6 +39,8 @@
    other programs (LP: #1284439)
  - Azure: if a reboot causes ephemeral storage to be re-provisioned
    Then we need to re-format it. (LP: #1292648)
+ - OpenNebula: support base64 encoded user-data
+   [Enol Fernandez, Peter Kotcauer]
 0.7.4:
  - fix issue mounting 'ephemeral0' if ephemeral0 was an alias for a
    partitioned block device with target filesystem on ephemeral0.1.
diff --git a/cloudinit/sources/DataSourceOpenNebula.py b/cloudinit/sources/DataSourceOpenNebula.py
index b0464cbb..34557f8b 100644
--- a/cloudinit/sources/DataSourceOpenNebula.py
+++ b/cloudinit/sources/DataSourceOpenNebula.py
@@ -4,11 +4,13 @@
 #    Copyright (C) 2012 Yahoo! Inc.
 #    Copyright (C) 2012-2013 CERIT Scientific Cloud
 #    Copyright (C) 2012-2013 OpenNebula.org
+#    Copyright (C) 2014 Consejo Superior de Investigaciones Cientificas
 #
 #    Author: Scott Moser <scott.moser@canonical.com>
 #    Author: Joshua Harlow <harlowja@yahoo-inc.com>
 #    Author: Vlastimil Holer <xholer@mail.muni.cz>
 #    Author: Javier Fontan <jfontan@opennebula.org>
+#    Author: Enol Fernandez <enolfc@ifca.unican.es>
 #
 #    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
@@ -22,6 +24,7 @@
 #    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
 import os
 import pwd
 import re
@@ -417,6 +420,16 @@ def read_context_disk_dir(source_dir, asuser=None):
     elif "USERDATA" in context:
         results['userdata'] = context["USERDATA"]
 
+    # b64decode user data if necessary (default)
+    if 'userdata' in results:
+        encoding = context.get('USERDATA_ENCODING',
+                               context.get('USER_DATA_ENCODING'))
+        if encoding == "base64":
+            try:
+                results['userdata'] = base64.b64decode(results['userdata'])
+            except TypeError:
+                LOG.warn("Failed base64 decoding of userdata")
+
     # generate static /etc/network/interfaces
     # only if there are any required context variables
     # http://opennebula.org/documentation:rel3.8:cong#network_configuration
diff --git a/tests/unittests/test_datasource/test_opennebula.py b/tests/unittests/test_datasource/test_opennebula.py
index 6fc5b2ac..ec6b752b 100644
--- a/tests/unittests/test_datasource/test_opennebula.py
+++ b/tests/unittests/test_datasource/test_opennebula.py
@@ -4,6 +4,7 @@ from cloudinit import util
 from mocker import MockerTestCase
 from tests.unittests.helpers import populate_dir
 
+from base64 import b64encode
 import os
 import pwd
 
@@ -164,10 +165,31 @@ class TestOpenNebulaDataSource(MockerTestCase):
 
             public_keys.append(SSH_KEY % (c + 1,))
 
-    def test_user_data(self):
+    def test_user_data_plain(self):
         for k in ('USER_DATA', 'USERDATA'):
             my_d = os.path.join(self.tmp, k)
-            populate_context_dir(my_d, {k: USER_DATA})
+            populate_context_dir(my_d, {k: USER_DATA,
+                                        'USERDATA_ENCODING': ''})
+            results = ds.read_context_disk_dir(my_d)
+
+            self.assertTrue('userdata' in results)
+            self.assertEqual(USER_DATA, results['userdata'])
+
+    def test_user_data_encoding_required_for_decode(self):
+        b64userdata = b64encode(USER_DATA)
+        for k in ('USER_DATA', 'USERDATA'):
+            my_d = os.path.join(self.tmp, k)
+            populate_context_dir(my_d, {k: b64userdata})
+            results = ds.read_context_disk_dir(my_d)
+
+            self.assertTrue('userdata' in results)
+            self.assertEqual(b64userdata, results['userdata'])
+
+    def test_user_data_base64_encoding(self):
+        for k in ('USER_DATA', 'USERDATA'):
+            my_d = os.path.join(self.tmp, k)
+            populate_context_dir(my_d, {k: b64encode(USER_DATA),
+                                        'USERDATA_ENCODING': 'base64'})
             results = ds.read_context_disk_dir(my_d)
 
             self.assertTrue('userdata' in results)