fix broken UTs for python3 compatibility

This fix does following:
1. decode byte string into utf-8 before json.load
2. encode unicode to utf-8 before md5 checksum calculation

Partially-Implements: blueprint designate-py3

Change-Id: I47e554fbcf3309fef724f50e3e67af601578e83c

designate/storage/impl_sqlalchemy/__init__.py

@@ -624,7 +624,8 @@ class SQLAlchemyStorage(sqlalchemy_base.SQLAlchemy, storage_base.Storage):
         Calculates the hash of the record, used to ensure record uniqueness.
         """
         md5 = hashlib.md5()
-        md5.update("%s:%s" % (record.recordset_id, record.data))
+        md5.update(("%s:%s" % (record.recordset_id,
+                               record.data)).encode('utf-8'))
 
         return md5.hexdigest()
 

designate/utils.py

@@ -131,13 +131,14 @@ def resource_string(*args):
 def load_schema(version, name):
     schema_string = resource_string('schemas', version, '%s.json' % name)
 
-    return json.loads(schema_string)
+    return json.loads(schema_string.decode('utf-8'))
 
 
 def load_template(template_name):
     template_string = resource_string('templates', template_name)
 
-    return Template(template_string, keep_trailing_newline=True)
+    return Template(template_string.decode('utf-8'),
+                    keep_trailing_newline=True)
 
 
 def render_template(template, **template_context):