Create a SerializableComparable class

Create a SerializableComparable class derived from the Serializable
class.

Added the following functions to the SerializableComparable class:
  '__eq__'
  '__ne__'

Disable the '__hash__' function in the SerializableComparable class as
some derived classes are mutable.

Use the SerializableComparable class in hardware.py and
extensions/base.py

This should make unit testing users of the class easier when doing a
self.assertEqual() or self.assertNotEqual()

Added some initial unit testing for encoding.py

Change-Id: If0f14b3bfe7f1391f65dd730a16a534afed0da82

4 files changed, 85 insertions, 5 deletions

diff --git a/ironic_python_agent/encoding.py b/ironic_python_agent/encoding.py
index 9022afd5..715d1341 100644
--- a/ironic_python_agent/encoding.py
+++ b/ironic_python_agent/encoding.py
@@ -25,6 +25,24 @@ class Serializable(object):
         return dict((f, getattr(self, f)) for f in self.serializable_fields)
 
 
+class SerializableComparable(Serializable):
+    """A Serializable class which supports some comparison operators
+
+    This class supports the '__eq__' and '__ne__' comparison operators, but
+    intentionally disables the '__hash__' operator as some child classes may be
+    mutable.  The addition of these comparison operators is mainly used to
+    assist with unit testing.
+    """
+
+    __hash__ = None
+
+    def __eq__(self, other):
+        return self.serialize() == other.serialize()
+
+    def __ne__(self, other):
+        return self.serialize() != other.serialize()
+
+
 class RESTJSONEncoder(json.JSONEncoder):
     """A slightly customized JSON encoder."""
     def encode(self, o):
diff --git a/ironic_python_agent/extensions/base.py b/ironic_python_agent/extensions/base.py
index baac978a..6f7de8e7 100644
--- a/ironic_python_agent/extensions/base.py
+++ b/ironic_python_agent/extensions/base.py
@@ -35,7 +35,7 @@ class AgentCommandStatus(object):
     CLEAN_VERSION_MISMATCH = u'CLEAN_VERSION_MISMATCH'
 
 
-class BaseCommandResult(encoding.Serializable):
+class BaseCommandResult(encoding.SerializableComparable):
     """Base class for command result."""
 
     serializable_fields = ('id', 'command_name', 'command_params',
diff --git a/ironic_python_agent/hardware.py b/ironic_python_agent/hardware.py
index ace35303..69d7e0ab 100644
--- a/ironic_python_agent/hardware.py
+++ b/ironic_python_agent/hardware.py
@@ -99,7 +99,7 @@ class HardwareType(object):
     MAC_ADDRESS = 'mac_address'
 
 
-class BlockDevice(encoding.Serializable):
+class BlockDevice(encoding.SerializableComparable):
     serializable_fields = ('name', 'model', 'size', 'rotational')
 
     def __init__(self, name, model, size, rotational):
@@ -109,7 +109,7 @@ class BlockDevice(encoding.Serializable):
         self.rotational = rotational
 
 
-class NetworkInterface(encoding.Serializable):
+class NetworkInterface(encoding.SerializableComparable):
     serializable_fields = ('name', 'mac_address', 'switch_port_descr',
                            'switch_chassis_descr', 'ipv4_address')
 
@@ -122,7 +122,7 @@ class NetworkInterface(encoding.Serializable):
         self.switch_chassis_descr = None
 
 
-class CPU(encoding.Serializable):
+class CPU(encoding.SerializableComparable):
     serializable_fields = ('model_name', 'frequency', 'count', 'architecture')
 
     def __init__(self, model_name, frequency, count, architecture):
@@ -132,7 +132,7 @@ class CPU(encoding.Serializable):
         self.architecture = architecture
 
 
-class Memory(encoding.Serializable):
+class Memory(encoding.SerializableComparable):
     serializable_fields = ('total', 'physical_mb')
     # physical = total + kernel binary + reserved space
 
diff --git a/ironic_python_agent/tests/unit/test_encoding.py b/ironic_python_agent/tests/unit/test_encoding.py
new file mode 100644
index 00000000..522dc968
--- /dev/null
+++ b/ironic_python_agent/tests/unit/test_encoding.py
@@ -0,0 +1,62 @@
+#    Copyright (C) 2015 Intel Corporation
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from oslotest import base as test_base
+
+from ironic_python_agent import encoding
+
+
+class SerializableTesting(encoding.Serializable):
+    serializable_fields = ('jack', 'jill')
+
+    def __init__(self, jack, jill):
+        self.jack = jack
+        self.jill = jill
+
+
+class SerializableComparableTesting(encoding.SerializableComparable):
+    serializable_fields = ('jack', 'jill')
+
+    def __init__(self, jack, jill):
+        self.jack = jack
+        self.jill = jill
+
+
+class TestSerializable(test_base.BaseTestCase):
+    def test_baseclass_serialize(self):
+        obj = encoding.Serializable()
+        self.assertEqual({}, obj.serialize())
+
+    def test_childclass_serialize(self):
+        expected = {'jack': 'hello', 'jill': 'world'}
+        obj = SerializableTesting('hello', 'world')
+        self.assertEqual(expected, obj.serialize())
+
+
+class TestSerializableComparable(test_base.BaseTestCase):
+
+    def test_childclass_equal(self):
+        obj1 = SerializableComparableTesting('hello', 'world')
+        obj2 = SerializableComparableTesting('hello', 'world')
+        self.assertEqual(obj1, obj2)
+
+    def test_childclass_notequal(self):
+        obj1 = SerializableComparableTesting('hello', 'world')
+        obj2 = SerializableComparableTesting('hello', 'world2')
+        self.assertNotEqual(obj1, obj2)
+
+    def test_childclass_hash(self):
+        # Ensure __hash__ is None
+        obj = SerializableComparableTesting('hello', 'world')
+        self.assertEqual(None, obj.__hash__)