Add dictionary param support to resources that have AWSHelperFn props.

tests/test_dict.py

@@ -1,7 +1,8 @@
 import unittest
-from troposphere import Template, Ref
+from troposphere import Ref, Tags, Template
 from troposphere import ecs
 from troposphere import iam
+from troposphere import s3
 
 
 class TestDict(unittest.TestCase):
@@ -32,7 +33,14 @@ def setUp(self):
  "HostPort": 5001
  }
  ],
- "Links": ["containerA", "containerB"],
+ "Links": ["containerA", "containerB"]
+ }
+
+ self.b = {
+ "BucketName": "bucketname",
+ "Tags": {
+ "tagname": "mytag"
+ }
  }
 
  def test_valid_data(self):
@@ -74,6 +82,10 @@ def test_invalid_subproperty_definition(self):
  with self.assertRaises(ValueError):
  ecs.ContainerDefinition.from_dict("mycontainer", self.d)
 
+ def test_sub_property_aws_helper_fn(self):
+ bkt = s3.Bucket.from_dict("mybucket", self.b)
+ self.assertIsInstance(bkt.Tags, Tags)
+
 
 if __name__ == '__main__':
  unittest.main()

troposphere/__init__.py

@@ -50,6 +50,16 @@ def is_aws_object_subclass(cls):
  return is_aws_object
 
 
+def is_aws_helper_function_subclass(cls):
+ is_aws_helper_function = False
+ try:
+ is_aws_helper_function = issubclass(cls, AWSHelperFn)
+ # prop_type isn't a class
+ except TypeError:
+ pass
+ return is_aws_helper_function
+
+
 def encode_to_dict(obj):
  if hasattr(obj, 'to_dict'):
  # Calling encode_to_dict to ensure object is
@@ -257,13 +267,16 @@ def _from_dict(cls, title=None, **kwargs):
  prop_name))
  prop_type = prop_attrs[0]
  value = kwargs[prop_name]
- is_aws_object = is_aws_object_subclass(prop_type)
- if is_aws_object:
+
+ if is_aws_object_subclass(prop_type):
  if not isinstance(value, collections.Mapping):
  raise ValueError("Property definition for %s must be "
  "a Mapping type" % prop_name)
  value = prop_type._from_dict(**value)
 
+ if is_aws_helper_function_subclass(prop_type):
+ value = prop_type(**value)
+
  if isinstance(prop_type, list):
  if not isinstance(value, list):
  raise TypeError("Attribute %s must be a "
@@ -277,6 +290,8 @@ def _from_dict(cls, title=None, **kwargs):
  "Property definition for %s must be "
  "a list of Mapping types" % prop_name)
  new_v = prop_type[0]._from_dict(**v)
+ if is_aws_helper_function_subclass(prop_type[0]):
+ new_v = prop_type(**v)
  new_value.append(new_v)
  value = new_value
  props[prop_name] = value