Support all the variants for writing files with cloudconfig

The patch fixes a small bug in cloudconfig._process_content, where the
chaining of encoders (gzip and base64 for instance) weren't treated
correctly. It also adds support for processing both lists of dicts and
dicts in the write-files plugin.
Also, we added tests for using !!binary| marker for yaml binary
streams, as well as a couple of other tests.

Change-Id: I9edcdcd93af4e058a0d1f8c9cdaa1b2aa9e9618d
Closes-Bug: #1409270

cloudbaseinit/plugins/windows/userdataplugins/cloudconfigplugins/write_files.py

@@ -17,6 +17,8 @@ import gzip
 import io
 import os
 
+import six
+
 from cloudbaseinit import exception
 from cloudbaseinit.openstack.common import log as logging
 from cloudbaseinit.plugins.windows.userdataplugins.cloudconfigplugins import (
@@ -56,7 +58,11 @@ def _convert_permissions(permissions):
 
 def _process_content(content, encoding):
     """Decode the content taking into consideration the encoding."""
-    result = str(content)
+    result = content
+    if six.PY3 and not isinstance(result, six.binary_type):
+        # At this point, content will be string, which is wrong for Python 3.
+        result = result.encode()
+
     steps = _decode_steps(encoding)
     if not steps:
         LOG.error("Unknown encoding, doing nothing.")
@@ -64,7 +70,7 @@ def _process_content(content, encoding):
 
     for mime_type in _decode_steps(encoding):
         if mime_type == GZIP_MIME:
-            bufferio = io.BytesIO(content)
+            bufferio = io.BytesIO(result)
             with gzip.GzipFile(fileobj=bufferio, mode='rb') as file_handle:
                 try:
                     result = file_handle.read()

cloudbaseinit/tests/plugins/windows/test_userdata.py

@@ -308,13 +308,23 @@ class TestCloudConfig(unittest.TestCase):
         cls.userdata = pkgutil.get_data('cloudbaseinit.tests.resources',
                                         'cloud_config_userdata').decode()
 
+    def create_tempfiles(self, number):
+        for _ in range(number):
+            tmp = _create_tempfile()
+            self.addCleanup(os.remove, tmp)
+            yield tmp
+
     def test_cloud_config_multipart(self):
-        tmp = _create_tempfile()
-        self.addCleanup(os.remove, tmp)
+        b64, b64_binary, gz, gz_binary = list(self.create_tempfiles(4))
 
-        service = FakeService(self.userdata.format(b64=tmp))
+        service = FakeService(self.userdata.format(b64=b64,
+                                                   b64_binary=b64_binary,
+                                                   gzip=gz,
+                                                   gzip_binary=gz_binary))
         self.plugin.execute(service, {})
-        self.assertTrue(os.path.exists(tmp))
 
-        with open(tmp) as stream:
-            self.assertEqual('42', stream.read())
+        for path in (b64, b64_binary, gz, gz_binary):
+            self.assertTrue(os.path.exists(path),
+                            "Path {} should exist.".format(path))
+            with open(path) as stream:
+                self.assertEqual('42', stream.read())

cloudbaseinit/tests/plugins/windows/userdataplugins/cloudconfigplugins/test_write_files.py

@@ -77,8 +77,10 @@ class WriteFilesPluginTests(unittest.TestCase):
         response = write_files._convert_permissions(mock.sentinel.invalid)
         self.assertEqual(write_files.DEFAULT_PERMISSIONS, response)
 
-    def test_write_file(self):
-        tmp = self._get_tempfile()
+    def test_write_file_list(self):
+        expected_logging = [
+            "Plugin 'invalid' is currently not supported",
+        ]
         code = textwrap.dedent("""
         write_files:
         -   encoding: b64
@@ -87,7 +89,23 @@ class WriteFilesPluginTests(unittest.TestCase):
             permissions: '0o466'
         invalid:
         - stuff: 1
-        """.format(tmp))
+        """)
+        self._test_write_file(code, expected_logging)
+
+    def test_write_file_dict(self):
+        code = textwrap.dedent("""
+        write_files:
+           encoding: b64
+           content: NDI=
+           path: {}
+           permissions: '0o466'
+        """)
+        self._test_write_file(code)
+
+    def _test_write_file(self, code, expected_logging=None):
+        tmp = self._get_tempfile()
+        code = code.format(tmp)
+
         with testutils.LogSnatcher('cloudbaseinit.plugins.windows.'
                                    'userdataplugins.cloudconfig') as snatcher:
             self.plugin.process_non_multipart(code)
@@ -97,8 +115,8 @@ class WriteFilesPluginTests(unittest.TestCase):
 
         with open(tmp) as stream:
             self.assertEqual('42', stream.read())
-        self.assertEqual(["Plugin 'invalid' is currently not supported"],
-                         snatcher.output)
+        if expected_logging is not None:
+            self.assertEqual(expected_logging, snatcher.output)
 
         # Test that the proper permissions were set. On Windows,
         # only the read bit is processed, the rest are ignored.
@@ -143,3 +161,24 @@ class WriteFilesPluginTests(unittest.TestCase):
             "Processing plugin write_files failed"))
         self.assertTrue(snatcher.output[0].endswith("ValueError"))
         self.assertFalse(os.path.exists('random_cloudbaseinit_test'))
+
+    def test_unknown_encoding(self):
+        tmp = self._get_tempfile()
+        code = textwrap.dedent("""
+        write_files:
+        -   content: NDI=
+            path: {}
+            permissions: '0o466'
+        """.format(tmp))
+        with testutils.LogSnatcher('cloudbaseinit.plugins.windows.'
+                                   'userdataplugins.cloudconfigplugins.'
+                                   'write_files') as snatcher:
+            self.plugin.process_non_multipart(code)
+
+        self.assertTrue(os.path.exists(tmp),
+                        "Expected path does not exist.")
+        with open(tmp) as stream:
+            self.assertEqual('NDI=', stream.read())
+
+        self.assertEqual(["Unknown encoding, doing nothing."],
+                         snatcher.output)

cloudbaseinit/tests/resources/cloud_config_userdata

@@ -11,4 +11,14 @@ write_files:
 -   encoding: b64
     content: NDI=
     path: {b64}
-    permissions: '0644'
+    permissions: '0644'
+-   content: !!binary |
+        NDI=
+    path: {b64_binary}
+- path: {gzip}
+  encoding: gzip+b64
+  content: H4sIAGUfoFQC/zMxAgCIsCQyAgAAAA==
+- path: {gzip_binary}
+  encoding: gzip
+  content: !!binary |
+      H4sIAGUfoFQC/zMxAgCIsCQyAgAAAA==