Add Image Customization Parser for VMware vSphere Hypervisor Support.

This is the first changeset submitted as a part of project to
add cloud-init support for VMware vSphere Hypervisor. This changeset
contains _only_ the changes for a simple python parser for a
Image Customization Specification file pushed by VMware vSphere
hypervisor into the guest VMs. In a later changeset, will be submitting
another patch to actually detect the underlying VMware vSphere hypervisor
and do the necessary customization.

1 files changed, 129 insertions, 0 deletions

diff --git a/cloudinit/sources/helpers/vmware/imc/config_file.py b/cloudinit/sources/helpers/vmware/imc/config_file.py
new file mode 100644
index 00000000..bb9fb7dc
--- /dev/null
+++ b/cloudinit/sources/helpers/vmware/imc/config_file.py
@@ -0,0 +1,129 @@
+# vi: ts=4 expandtab
+#
+#    Copyright (C) 2015 Canonical Ltd.
+#    Copyright (C) 2015 VMware Inc.
+#
+#    Author: Sankar Tanguturi <stanguturi@vmware.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 logging
+
+try:
+    import configparser
+except ImportError:
+    import ConfigParser as configparser
+
+from .config_source import ConfigSource
+
+logger = logging.getLogger(__name__)
+
+
+class ConfigFile(ConfigSource, dict):
+    """ConfigFile module to load the content from a specified source."""
+
+    def __init__(self, filename):
+        self._loadConfigFile(filename)
+        pass
+
+    def _insertKey(self, key, val):
+        """
+        Inserts a Key Value pair.
+
+        Keyword arguments:
+        key -- The key to insert
+        val -- The value to insert for the key
+
+        """
+        key = key.strip()
+        val = val.strip()
+
+        if key.startswith('-') or '|-' in key:
+            canLog = False
+        else:
+            canLog = True
+
+        # "sensitive" settings shall not be logged
+        if canLog:
+            logger.debug("ADDED KEY-VAL :: '%s' = '%s'" % (key, val))
+        else:
+            logger.debug("ADDED KEY-VAL :: '%s' = '*****************'" % key)
+
+        self[key] = val
+
+    def _loadConfigFile(self, filename):
+        """
+        Parses properties from the specified config file.
+
+        Any previously available properties will be removed.
+        Sensitive data will not be logged in case the key starts
+        from '-'.
+
+        Keyword arguments:
+        filename - The full path to the config file.
+        """
+        logger.info('Parsing the config file %s.' % filename)
+
+        config = configparser.ConfigParser()
+        config.optionxform = str
+        config.read(filename)
+
+        self.clear()
+
+        for category in config.sections():
+            logger.debug("FOUND CATEGORY = '%s'" % category)
+
+            for (key, value) in config.items(category):
+                self._insertKey(category + '|' + key, value)
+
+    def should_keep_current_value(self, key):
+        """
+        Determines whether a value for a property must be kept.
+
+        If the propery is missing, it is treated as it should be not
+        changed by the engine.
+
+        Keyword arguments:
+        key -- The key to search for.
+        """
+        # helps to distinguish from "empty" value which is used to indicate
+        # "removal"
+        return key not in self
+
+    def should_remove_current_value(self, key):
+        """
+        Determines whether a value for the property must be removed.
+
+        If the specified key is empty, it is treated as it should be
+        removed by the engine.
+
+        Return true if the value can be removed, false otherwise.
+
+        Keyword arguments:
+        key -- The key to search for.
+        """
+        # helps to distinguish from "missing" value which is used to indicate
+        # "keeping unchanged"
+        if key in self:
+            return not bool(self[key])
+        else:
+            return False
+
+    def get_count_with_prefix(self, prefix):
+        """
+        Return the total count of keys that start with the specified prefix.
+
+        Keyword arguments:
+        prefix -- prefix of the key
+        """
+        return len([key for key in self if key.startswith(prefix)])