From 94e969fed5de7b298d19a23a68d4c52081a965e8 Mon Sep 17 00:00:00 2001
From: Joseph Lawson <joe@joekiller.com>
Date: Wed, 22 Oct 2014 23:58:42 -0400
Subject: [PATCH] Enhance DescribeStacks. Keep track of deleted stacks. Stack
 status.

Made describe_stacks more in line with http://docs.aws.amazon.com/AWSCloudFormation/latest/APIReference/API_DescribeStackResource.html
---
 moto/cloudformation/models.py                 | 17 ++++++++--
 moto/cloudformation/responses.py              | 12 ++++---
 .../test_cloudformation_stack_crud.py         | 31 +++++++++++++++++++
 3 files changed, 52 insertions(+), 8 deletions(-)

diff --git a/moto/cloudformation/models.py b/moto/cloudformation/models.py
index d4420cafd..f54182174 100644
--- a/moto/cloudformation/models.py
+++ b/moto/cloudformation/models.py
@@ -12,6 +12,7 @@ class FakeStack(object):
         self.stack_id = stack_id
         self.name = name
         self.template = template
+        self.status = 'CREATE_COMPLETE'
 
         template_dict = json.loads(self.template)
         self.description = template_dict.get('Description')
@@ -35,6 +36,7 @@ class CloudFormationBackend(BaseBackend):
 
     def __init__(self):
         self.stacks = {}
+        self.deleted_stacks = {}
 
     def create_stack(self, name, template):
         stack_id = generate_stack_id(name)
@@ -42,10 +44,16 @@ class CloudFormationBackend(BaseBackend):
         self.stacks[stack_id] = new_stack
         return new_stack
 
-    def describe_stacks(self, names):
+    def describe_stacks(self, name_or_stack_id):
         stacks = self.stacks.values()
-        if names:
-            return [stack for stack in stacks if stack.name in names]
+        if name_or_stack_id:
+            for stack in stacks:
+                if stack.name == name_or_stack_id or stack.stack_id == name_or_stack_id:
+                    return [stack]
+            deleted_stacks = self.deleted_stacks.values()
+            for stack in deleted_stacks:
+                if stack.stack_id == name_or_stack_id:
+                    return [stack]
         else:
             return stacks
 
@@ -68,6 +76,9 @@ class CloudFormationBackend(BaseBackend):
     def delete_stack(self, name_or_stack_id):
         if name_or_stack_id in self.stacks:
             # Delete by stack id
+            stack = self.stacks.pop(name_or_stack_id, None)
+            stack.status = 'DELETE_COMPLETE'
+            self.deleted_stacks[stack.stack_id] = stack
             return self.stacks.pop(name_or_stack_id, None)
         else:
             # Delete by stack name
diff --git a/moto/cloudformation/responses.py b/moto/cloudformation/responses.py
index 7d6690323..4267a6e48 100644
--- a/moto/cloudformation/responses.py
+++ b/moto/cloudformation/responses.py
@@ -27,8 +27,10 @@ class CloudFormationResponse(BaseResponse):
         return json.dumps(stack_body)
 
     def describe_stacks(self):
-        names = [value[0] for key, value in self.querystring.items() if "StackName" in key]
-        stacks = cloudformation_backend.describe_stacks(names)
+        stack_name_or_id = None
+        if self._get_param('StackName'):
+            stack_name_or_id = self.querystring.get('StackName')[0]
+        stacks = cloudformation_backend.describe_stacks(stack_name_or_id)
 
         template = Template(DESCRIBE_STACKS_TEMPLATE)
         return template.render(stacks=stacks)
@@ -86,7 +88,7 @@ DESCRIBE_STACKS_TEMPLATE = """<DescribeStacksResult>
       <StackName>{{ stack.name }}</StackName>
       <StackId>{{ stack.stack_id }}</StackId>
       <CreationTime>2010-07-27T22:28:28Z</CreationTime>
-      <StackStatus>CREATE_COMPLETE</StackStatus>
+      <StackStatus>{{ stack.status }}</StackStatus>
       <DisableRollback>false</DisableRollback>
       <Outputs>
       {% for output in stack.stack_outputs %}
@@ -108,7 +110,7 @@ LIST_STACKS_RESPONSE = """<ListStacksResponse>
     {% for stack in stacks %}
     <member>
         <StackId>{{ stack.id }}</StackId>
-        <StackStatus>CREATE_IN_PROGRESS</StackStatus>
+        <StackStatus>{{ stack.status }}</StackStatus>
         <StackName>{{ stack.name }}</StackName>
         <CreationTime>2011-05-23T15:47:44Z</CreationTime>
         <TemplateDescription>{{ stack.description }}</TemplateDescription>
@@ -129,7 +131,7 @@ LIST_STACKS_RESOURCES_RESPONSE = """<DescribeStackResourcesResult>
       <PhysicalResourceId>{{ resource.physical_resource_id }}</PhysicalResourceId>
       <ResourceType>{{ resource.type }}</ResourceType>
       <Timestamp>2010-07-27T22:27:28Z</Timestamp>
-      <ResourceStatus>CREATE_COMPLETE</ResourceStatus>
+      <ResourceStatus>{{ stack.status }}</ResourceStatus>
     </member>
     {% endfor %}
   </StackResources>
diff --git a/tests/test_cloudformation/test_cloudformation_stack_crud.py b/tests/test_cloudformation/test_cloudformation_stack_crud.py
index fdbe7481b..f818e42ef 100644
--- a/tests/test_cloudformation/test_cloudformation_stack_crud.py
+++ b/tests/test_cloudformation/test_cloudformation_stack_crud.py
@@ -47,6 +47,37 @@ def test_describe_stack_by_name():
     stack.stack_name.should.equal('test_stack')
 
 
+@mock_cloudformation
+def test_describe_stack_by_stack_id():
+    conn = boto.connect_cloudformation()
+    conn.create_stack(
+        "test_stack",
+        template_body=dummy_template_json,
+    )
+
+    stack = conn.describe_stacks("test_stack")[0]
+    stack_by_id = conn.describe_stacks(stack.stack_id)[0]
+    stack_by_id.stack_id.should.equal(stack.stack_id)
+    stack_by_id.stack_name.should.equal("test_stack")
+
+
+@mock_cloudformation
+def test_describe_deleted_stack():
+    conn = boto.connect_cloudformation()
+    conn.create_stack(
+        "test_stack",
+        template_body=dummy_template_json,
+    )
+
+    stack = conn.describe_stacks("test_stack")[0]
+    stack_id = stack.stack_id
+    conn.delete_stack(stack.stack_id)
+    stack_by_id = conn.describe_stacks(stack_id)[0]
+    stack_by_id.stack_id.should.equal(stack.stack_id)
+    stack_by_id.stack_name.should.equal("test_stack")
+    stack_by_id.stack_status.should.equal("DELETE_COMPLETE")
+
+
 @mock_cloudformation
 def test_get_template_by_name():
     conn = boto.connect_cloudformation()