Merge "Add default namespace to apiclient"

freezer/apiclient/client.py

@@ -30,6 +30,7 @@ from jobs import JobManager
 from actions import ActionManager
 from sessions import SessionManager
 from oslo_config import cfg
+from freezer.utils import Namespace
 
 CONF = cfg.CONF
 
@@ -195,6 +196,10 @@ class Client(object):
                  verify=True):
 
         self.opts = opts
+        # this creates a namespace for self.opts when the client is
+        # created from other method rather than command line arguments.
+        if self.opts is None:
+            self.opts = Namespace({})
         if token:
             self.opts.os_token = token
         if username:

freezer/utils.py

@@ -28,6 +28,8 @@ import sys
 
 from functools import wraps
 
+from collections import Mapping, Sequence
+
 
 class OpenstackOptions:
     """
@@ -442,3 +444,76 @@ def delete_file(path_to_file):
         os.remove(path_to_file)
     except Exception:
         logging.warning("Error deleting file {0}".format(path_to_file))
+
+
+class Namespace(dict):
+    """A dict subclass that exposes its items as attributes.
+
+    Warning: Namespace instances do not have direct access to the
+    dict methods.
+
+    """
+
+    def __init__(self, obj={}):
+        super(Namespace, self).__init__(obj)
+
+    def __dir__(self):
+        return tuple(self)
+
+    def __repr__(self):
+        return "%s(%s)" % (type(self).__name__,
+                           super(Namespace, self).__repr__())
+
+    def __getattribute__(self, name):
+        try:
+            return self[name]
+        except KeyError:
+            # Return None in case the value doesn't exists
+            # this is not an issue for the apiclient because it skips
+            # None values
+            return None
+
+    def __setattr__(self, name, value):
+        self[name] = value
+
+    def __delattr__(self, name):
+        del self[name]
+
+    @classmethod
+    def from_object(cls, obj, names=None):
+        if names is None:
+            names = dir(obj)
+        ns = {name:getattr(obj, name) for name in names}
+        return cls(ns)
+
+    @classmethod
+    def from_mapping(cls, ns, names=None):
+        if names:
+            ns = {name: ns[name] for name in names}
+        return cls(ns)
+
+    @classmethod
+    def from_sequence(cls, seq, names=None):
+        if names:
+            seq = {name: val for name, val in seq if name in names}
+        return cls(seq)
+
+    @staticmethod
+    def hasattr(ns, name):
+        try:
+            object.__getattribute__(ns, name)
+        except AttributeError:
+            return False
+        return True
+
+    @staticmethod
+    def getattr(ns, name):
+        return object.__getattribute__(ns, name)
+
+    @staticmethod
+    def setattr(ns, name, value):
+        return object.__setattr__(ns, name, value)
+
+    @staticmethod
+    def delattr(ns, name):
+        return object.__delattr__(ns, name)