From 85a329aa8b89f60bcb79204d2a313286e756b15a Mon Sep 17 00:00:00 2001
From: Filippos Chalvatzoglou <filippos@gmail.com>
Date: Thu, 9 Mar 2017 13:42:16 +0000
Subject: [PATCH] Currently when deleting tail blocks forever

bootstrap_cfn 's utils.tail() blocks forever on stack deletion.
Added a helper function to detect when the status is deleted or
failed to delete (to represent the cfn_delete event finishing).
Note that after delete_done it may be possible that the stack
still has lingering resources, that's why we leave it vague,
and only suggest that the 'cfn delete event' finished.
---
 bootstrap_cfn/cloudformation.py |  7 +++++
 bootstrap_cfn/utils.py          |  2 ++
 tests/test.py                   | 54 +++++++++++++++++++++++++++++++++
 3 files changed, 63 insertions(+)

diff --git a/bootstrap_cfn/cloudformation.py b/bootstrap_cfn/cloudformation.py
index 826369b..7cbb215 100644
--- a/bootstrap_cfn/cloudformation.py
+++ b/bootstrap_cfn/cloudformation.py
@@ -35,6 +35,13 @@ def stack_done(self, stack_id):
             return True
         return False
 
+    def stack_delete_done(self, stack_id):
+        stack_events = self.conn_cfn.describe_stack_events(stack_id)
+        if stack_events[0].resource_type == 'AWS::CloudFormation::Stack'\
+                and stack_events[0].resource_status in ['DELETE_COMPLETE', 'DELETE_FAILED']:
+            return True
+        return False
+
     def wait_for_stack_done(self, stack_id, timeout=3600, interval=30):
         return utils.timeout(timeout, interval)(self.stack_done)(stack_id)
 
diff --git a/bootstrap_cfn/utils.py b/bootstrap_cfn/utils.py
index 027514b..862d880 100644
--- a/bootstrap_cfn/utils.py
+++ b/bootstrap_cfn/utils.py
@@ -112,6 +112,8 @@ def tail_print(e):
             break
         elif stack.stack_done(stack_name):
             break
+        elif stack.stack_delete_done(stack_name):
+            break
         events = get_events(stack, stack_name)
         for e in events:
             if e.event_id not in seen:
diff --git a/tests/test.py b/tests/test.py
index c3db5ec..9591fc8 100644
--- a/tests/test.py
+++ b/tests/test.py
@@ -235,6 +235,60 @@ def test_stack_not_done(self):
         self.assertFalse(cloudformation.Cloudformation(
             self.env.aws_profile).stack_done(self.stack_name))
 
+    def test_stack_delete_done(self):
+        stack_evt_mock = mock.Mock()
+        rt = mock.PropertyMock(return_value='AWS::CloudFormation::Stack')
+        rs = mock.PropertyMock(return_value='DELETE_COMPLETE')
+        type(stack_evt_mock).resource_type = rt
+        type(stack_evt_mock).resource_status = rs
+        mock_config = {'describe_stack_events.return_value': [stack_evt_mock]}
+
+        cf_mock = mock.Mock()
+        cf_connect_result = mock.Mock(name='cf_connect')
+        cf_mock.return_value = cf_connect_result
+        cf_connect_result.configure_mock(**mock_config)
+
+        boto.cloudformation.connect_to_region = cf_mock
+
+        self.assertTrue(cloudformation.Cloudformation(
+            self.env.aws_profile).stack_delete_done(self.stack_name))
+
+    def test_stack_delete_failed_but_done(self):
+        stack_evt_mock = mock.Mock()
+        rt = mock.PropertyMock(return_value='AWS::CloudFormation::Stack')
+        rs = mock.PropertyMock(return_value='DELETE_FAILED')
+        type(stack_evt_mock).resource_type = rt
+        type(stack_evt_mock).resource_status = rs
+        mock_config = {'describe_stack_events.return_value': [stack_evt_mock]}
+
+        cf_mock = mock.Mock()
+        cf_connect_result = mock.Mock(name='cf_connect')
+        cf_mock.return_value = cf_connect_result
+        cf_connect_result.configure_mock(**mock_config)
+
+        boto.cloudformation.connect_to_region = cf_mock
+
+        self.assertTrue(cloudformation.Cloudformation(
+            self.env.aws_profile).stack_delete_done(self.stack_name))
+
+    def test_stack_not_delete_done(self):
+        stack_evt_mock = mock.Mock()
+        rt = mock.PropertyMock(return_value='AWS::CloudFormation::Stack')
+        rs = mock.PropertyMock(return_value='DELETE_ME')
+        type(stack_evt_mock).resource_type = rt
+        type(stack_evt_mock).resource_status = rs
+        mock_config = {'describe_stack_events.return_value': [stack_evt_mock]}
+
+        cf_mock = mock.Mock()
+        cf_connect_result = mock.Mock(name='cf_connect')
+        cf_mock.return_value = cf_connect_result
+        cf_connect_result.configure_mock(**mock_config)
+
+        boto.cloudformation.connect_to_region = cf_mock
+
+        self.assertFalse(cloudformation.Cloudformation(
+            self.env.aws_profile).stack_delete_done(self.stack_name))
+
     def test_ssl_upload(self):
         iam_mock = mock.Mock()
         iam_connect_result = mock.Mock(name='iam_connect')