Convenience methods in base model class

This change adds a BaseModel type which Plan inherits from along with
implementations of __eq__ and __repr__ to assist with testing and
debugging.

The __repr__ is a compact yaml representation which starts with the
class name.

The __eq__ asserts the other is of the same type, and then compares the
class __dict__ (which includes the class attributes)

Change-Id: I3a6aafc680637b2ec379f206a731796c24d5c7bb

tripleo_common/core/models.py

@@ -14,8 +14,23 @@
 # under the License.
 import datetime
 
+import yaml
 
-class Plan(object):
+
+class BaseModel(object):
+
+    def __repr__(self, *args, **kwargs):
+        repr_ = {self.__class__.__name__: self.__dict__}
+        return yaml.safe_dump(repr_, default_flow_style=True)
+
+    def __eq__(self, other):
+        if not (isinstance(other, self.__class__) or
+                isinstance(self, other.__class__)):
+            return False
+        return self.__dict__ == getattr(other, '__dict__')
+
+
+class Plan(BaseModel):
 
     def __init__(self, name):
         self.name = name

tripleo_common/tests/core/test_models.py

@@ -16,6 +16,9 @@
 import datetime
 import time
 
+import six
+import yaml
+
 from tripleo_common.core.models import Plan
 from tripleo_common.tests import base
 
@@ -48,3 +51,20 @@ class ModelTest(base.TestCase):
         expected_date = datetime.datetime.fromtimestamp(
             float(self.timestamp))
         self.assertEqual(expected_date, plan.created_date(), "Date mismatch")
+
+    def test_eq(self):
+        self.assertEqual(Plan('foo'), Plan('foo'))
+        self.assertNotEqual(Plan('bar'), Plan('foo'))
+        self.assertNotEqual(Plan('bar'), None)
+
+        class thing(object):
+            pass
+
+        self.assertNotEqual(Plan('bar'), thing())
+
+    def test_repr(self):
+        plan = Plan('foo')
+        plan_str = six.text_type(plan)
+        self.assertEqual({'Plan': {
+            'files': {}, 'name': 'foo', 'metadata': {}
+        }}, yaml.safe_load(plan_str))