From 186ee6a5a4422934f098794d08d8184771c50f88 Mon Sep 17 00:00:00 2001
From: Steve Pulec <spulec@gmail.com>
Date: Mon, 29 Dec 2014 22:12:23 -0500
Subject: [PATCH] Add cloudformation stack parsing for S3 keys.

---
 moto/cloudformation/responses.py              | 14 ++++++++++++
 .../test_cloudformation_stack_crud.py         | 22 ++++++++++++++++++-
 2 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/moto/cloudformation/responses.py b/moto/cloudformation/responses.py
index 2a79c06c..d419e7ad 100644
--- a/moto/cloudformation/responses.py
+++ b/moto/cloudformation/responses.py
@@ -1,7 +1,10 @@
 from __future__ import unicode_literals
+
 import json
+import urlparse
 
 from moto.core.responses import BaseResponse
+from moto.s3 import s3_backend
 from .models import cloudformation_backends
 
 
@@ -11,9 +14,20 @@ class CloudFormationResponse(BaseResponse):
     def cloudformation_backend(self):
         return cloudformation_backends[self.region]
 
+    def _get_stack_from_s3_url(self, template_url):
+        template_url_parts = urlparse.urlparse(template_url)
+        bucket_name = template_url_parts.netloc.split(".")[0]
+        key_name = template_url_parts.path.lstrip("/")
+
+        key = s3_backend.get_key(bucket_name, key_name)
+        return key.value
+
     def create_stack(self):
         stack_name = self._get_param('StackName')
         stack_body = self._get_param('TemplateBody')
+        template_url = self._get_param('TemplateURL')
+        if template_url:
+            stack_body = self._get_stack_from_s3_url(template_url)
         stack_notification_arns = self._get_multi_param('NotificationARNs.member')
 
         stack = self.cloudformation_backend.create_stack(
diff --git a/tests/test_cloudformation/test_cloudformation_stack_crud.py b/tests/test_cloudformation/test_cloudformation_stack_crud.py
index f9754239..ec521ee1 100644
--- a/tests/test_cloudformation/test_cloudformation_stack_crud.py
+++ b/tests/test_cloudformation/test_cloudformation_stack_crud.py
@@ -3,13 +3,15 @@ from __future__ import unicode_literals
 import json
 
 import boto
+import boto.s3
+import boto.s3.key
 import boto.cloudformation
 import sure  # noqa
 # Ensure 'assert_raises' context manager support for Python 2.6
 import tests.backport_assert_raises  # noqa
 from nose.tools import assert_raises
 
-from moto import mock_cloudformation
+from moto import mock_cloudformation, mock_s3
 from moto.cloudformation.exceptions import ValidationError
 
 dummy_template = {
@@ -66,6 +68,24 @@ def test_create_stack_with_notification_arn():
     [n.value for n in stack.notification_arns].should.contain('arn:aws:sns:us-east-1:123456789012:fake-queue')
 
 
+@mock_cloudformation
+@mock_s3
+def test_create_stack_from_s3_url():
+    s3_conn = boto.s3.connect_to_region('us-west-1')
+    bucket = s3_conn.create_bucket("foobar")
+    key = boto.s3.key.Key(bucket)
+    key.key = "template-key"
+    key.set_contents_from_string(dummy_template_json)
+    key_url = key.generate_url(expires_in=0, query_auth=False)
+
+    conn = boto.cloudformation.connect_to_region('us-west-1')
+    conn.create_stack('new-stack', template_url=key_url)
+
+    stack = conn.describe_stacks()[0]
+    stack.stack_name.should.equal('new-stack')
+    stack.get_template().should.equal(dummy_template)
+
+
 @mock_cloudformation
 def test_describe_stack_by_name():
     conn = boto.connect_cloudformation()