From bcc3e57949831b31661c1c91d739128e8bbd56d9 Mon Sep 17 00:00:00 2001
From: David Wilcox <dave@davidgwilcox.com>
Date: Sun, 5 Mar 2017 14:26:23 +1100
Subject: [PATCH] Cloudformation ResourceMaps incorrectly share namespaces for
 Conditions and Resources (#828)

* add tests to check CF's conditions and resources have distinct namespace

* separate the resource and condition namespaces for CF
---
 moto/cloudformation/parsing.py                | 14 ++---
 .../test_cloudformation_stack_crud.py         | 54 +++++++++++++++++++
 2 files changed, 61 insertions(+), 7 deletions(-)

diff --git a/moto/cloudformation/parsing.py b/moto/cloudformation/parsing.py
index 521658cee..fdc569dc1 100644
--- a/moto/cloudformation/parsing.py
+++ b/moto/cloudformation/parsing.py
@@ -143,7 +143,7 @@ def clean_json(resource_json, resources_map):
 
         if 'Fn::If' in resource_json:
             condition_name, true_value, false_value = resource_json['Fn::If']
-            if resources_map[condition_name]:
+            if resources_map.lazy_condition_map[condition_name]:
                 return clean_json(true_value, resources_map)
             else:
                 return clean_json(false_value, resources_map)
@@ -206,7 +206,7 @@ def parse_resource(logical_id, resource_json, resources_map):
 
 def parse_and_create_resource(logical_id, resource_json, resources_map, region_name):
     condition = resource_json.get('Condition')
-    if condition and not resources_map[condition]:
+    if condition and not resources_map.lazy_condition_map[condition]:
         # If this has a False condition, don't create the resource
         return None
 
@@ -352,13 +352,13 @@ class ResourceMap(collections.Mapping):
 
     def load_conditions(self):
         conditions = self._template.get('Conditions', {})
-        lazy_condition_map = LazyDict()
+        self.lazy_condition_map = LazyDict()
         for condition_name, condition in conditions.items():
-            lazy_condition_map[condition_name] = functools.partial(parse_condition,
-                condition, self._parsed_resources, lazy_condition_map)
+            self.lazy_condition_map[condition_name] = functools.partial(parse_condition,
+                condition, self._parsed_resources, self.lazy_condition_map)
 
-        for condition_name in lazy_condition_map:
-            self._parsed_resources[condition_name] = lazy_condition_map[condition_name]
+        for condition_name in self.lazy_condition_map:
+            _ = self.lazy_condition_map[condition_name]
 
     def create(self):
         self.load_mapping()
diff --git a/tests/test_cloudformation/test_cloudformation_stack_crud.py b/tests/test_cloudformation/test_cloudformation_stack_crud.py
index e45dafbfa..0696d5ada 100644
--- a/tests/test_cloudformation/test_cloudformation_stack_crud.py
+++ b/tests/test_cloudformation/test_cloudformation_stack_crud.py
@@ -279,6 +279,60 @@ def test_cloudformation_params():
     param.value.should.equal('testing123')
 
 
+@mock_cloudformation()
+def test_cloudformation_params_conditions_and_resources_are_distinct():
+    dummy_template = {
+        "AWSTemplateFormatVersion": "2010-09-09",
+        "Description": "Stack 1",
+        "Conditions": {
+            "FooEnabled": {
+                "Fn::Equals": [
+                    {
+                        "Ref": "FooEnabled"
+                    },
+                    "true"
+                ]
+            },
+            "FooDisabled": {
+                "Fn::Not": [
+                    {
+                        "Fn::Equals": [
+                            {
+                                "Ref": "FooEnabled"
+                            },
+                            "true"
+                        ]
+                    }
+                ]
+            }
+        },
+        "Parameters": {
+            "FooEnabled": {
+                "Type": "String",
+                "AllowedValues": [
+                    "true",
+                    "false"
+                ]
+            }
+        },
+        "Resources": {
+            "Bar": {
+                "Properties": {
+                    "CidrBlock": "192.168.0.0/16",
+                },
+                "Condition": "FooDisabled",
+                "Type": "AWS::EC2::VPC"
+            }
+        }
+    }
+    dummy_template_json = json.dumps(dummy_template)
+    cfn = boto.connect_cloudformation()
+    cfn.create_stack('test_stack1', template_body=dummy_template_json, parameters=[('FooEnabled', 'true')])
+    stack = cfn.describe_stacks('test_stack1')[0]
+    resources = stack.list_resources()
+    assert not [resource for resource in resources if resource.logical_resource_id == 'Bar']
+
+
 @mock_cloudformation
 def test_stack_tags():
     conn = boto.connect_cloudformation()