From 80cbfa38ae4ba7add2883697ed69857c88966a73 Mon Sep 17 00:00:00 2001
From: Kobi Samoray <ksamoray@vmware.com>
Date: Thu, 23 Feb 2017 14:41:11 +0200
Subject: [PATCH] Recurse dictionary generation in model to_dict()

Data model to_dict() methods do not recurse into object hierarchy.
While trying to transfer an object via RPC to a non-octavia services.
the object members are also required.

Change-Id: Ic8d85447d3e20c7a0fa865a400742bf3ac294843
---
 octavia/common/data_models.py               | 42 +++++++++++++---
 octavia/tests/unit/api/common/test_types.py | 55 +++++++++++++++++++++
 2 files changed, 89 insertions(+), 8 deletions(-)

diff --git a/octavia/common/data_models.py b/octavia/common/data_models.py
index a476764f3d..f8e995ed73 100644
--- a/octavia/common/data_models.py
+++ b/octavia/common/data_models.py
@@ -15,6 +15,7 @@
 #    under the License.
 
 import re
+import six
 
 from sqlalchemy.orm import collections
 
@@ -22,19 +23,44 @@ from octavia.common import constants
 
 
 class BaseDataModel(object):
-
-    # NOTE(brandon-logan) This does not discover dicts for relationship
-    # attributes.
-    def to_dict(self):
+    def to_dict(self, calling_classes=None, recurse=False, **kwargs):
         """Converts a data model to a dictionary."""
+        calling_classes = calling_classes or []
         ret = {}
         for attr in self.__dict__:
-            if attr.startswith('_'):
+            if attr.startswith('_') or not kwargs.get(attr, True):
                 continue
-            if isinstance(getattr(self, attr), (BaseDataModel, list)):
-                ret[attr] = None
+            value = self.__dict__[attr]
+
+            if recurse:
+                if isinstance(getattr(self, attr), list):
+                    ret[attr] = []
+                    for item in value:
+                        if isinstance(item, BaseDataModel):
+                            if type(self) not in calling_classes:
+                                ret[attr].append(
+                                    item.to_dict(calling_classes=(
+                                        calling_classes + [type(self)])))
+                            else:
+                                ret[attr] = None
+                        else:
+                            ret[attr] = item
+                elif isinstance(getattr(self, attr), BaseDataModel):
+                    if type(self) not in calling_classes:
+                        ret[attr] = value.to_dict(
+                            calling_classes=calling_classes + [type(self)])
+                    else:
+                        ret[attr] = None
+                elif six.PY2 and isinstance(value, six.text_type):
+                    ret[attr.encode('utf8')] = value.encode('utf8')
+                else:
+                    ret[attr] = value
             else:
-                ret[attr] = self.__dict__[attr]
+                if isinstance(getattr(self, attr), (BaseDataModel, list)):
+                    ret[attr] = None
+                else:
+                    ret[attr] = value
+
         return ret
 
     def __eq__(self, other):
diff --git a/octavia/tests/unit/api/common/test_types.py b/octavia/tests/unit/api/common/test_types.py
index d70a8e279b..5e358e07bd 100644
--- a/octavia/tests/unit/api/common/test_types.py
+++ b/octavia/tests/unit/api/common/test_types.py
@@ -98,3 +98,58 @@ class TestTypeDataModelRenames(base.TestCase):
         type_dict = TestTypeTenantProject(tenant_id='1234').to_dict()
         self.assertEqual('1234', type_dict['project_id'])
         self.assertNotIn('tenant_id', type_dict)
+
+
+class TestToDictModel(data_models.BaseDataModel):
+    def __init__(self, text, parent=None):
+        self.parent = parent
+        self.child = None
+        self.children = None
+        self.text = text
+
+    def set_children(self, children):
+        self.children = children
+
+    def set_child(self, child):
+        self.child = child
+
+    def set_parent(self, parent):
+        self.parent = parent
+
+
+class TestDataModelToDict(base.TestCase):
+    RECURSED_RESULT = {'parent': None,
+                       'text': 'parent_text',
+                       'child': {'parent': None,
+                                 'text': 'child_text',
+                                 'child': None,
+                                 'children': None},
+                       'children': [
+                           {'parent': None,
+                            'text': 'child1_text',
+                            'child': None,
+                            'children': None},
+                           {'parent': None,
+                            'text': 'child2_text',
+                            'child': None,
+                            'children': None}]}
+
+    NO_RECURSE_RESULT = {'parent': None,
+                         'text': 'parent_text',
+                         'child': None,
+                         'children': None}
+
+    def setUp(self):
+        super(TestDataModelToDict, self).setUp()
+        self.model = TestToDictModel('parent_text')
+        self.model.set_child(TestToDictModel('child_text', self.model))
+        self.model.set_children([TestToDictModel('child1_text', self.model),
+                                 TestToDictModel('child2_text', self.model)])
+
+    def test_to_dict_no_recurse(self):
+        self.assertEqual(self.model.to_dict(),
+                         self.NO_RECURSE_RESULT)
+
+    def test_to_dict_recurse(self):
+        self.assertEqual(self.model.to_dict(recurse=True),
+                         self.RECURSED_RESULT)