From f915b1b33fedc225b7758e291b421d47c8cd555e Mon Sep 17 00:00:00 2001
From: Angus Salkeld <asalkeld@redhat.com>
Date: Mon, 21 Oct 2013 07:24:02 -1000
Subject: [PATCH] Add support to disable resources

To remove a resource, you add the following to the global environment:

resource_registry:
  'AWS::*':

implements blueprint exclude-resources-option

Change-Id: Ia7c6c78ad3c1850ea20dd942d8d52957b5ad2b11
---
 heat/engine/environment.py     | 24 +++++++++++++++-
 heat/tests/test_environment.py | 52 ++++++++++++++++++++++++++++++++++
 2 files changed, 75 insertions(+), 1 deletion(-)

diff --git a/heat/engine/environment.py b/heat/engine/environment.py
index 6dd73f08f3..a441563e84 100644
--- a/heat/engine/environment.py
+++ b/heat/engine/environment.py
@@ -54,6 +54,8 @@ class ResourceInfo(object):
         self.user_resource = True
 
     def __eq__(self, other):
+        if other is None:
+            return False
         return (self.path == other.path and
                 self.value == other.value and
                 self.user_resource == other.user_resource)
@@ -154,7 +156,9 @@ class ResourceRegistry(object):
 
     def _load_registry(self, path, registry):
         for k, v in iter(registry.items()):
-            if isinstance(v, dict):
+            if v is None:
+                self._register_info(path + [k], None)
+            elif isinstance(v, dict):
                 self._load_registry(path + [k], v)
             else:
                 self._register_info(path + [k],
@@ -173,6 +177,24 @@ class ResourceRegistry(object):
                 registry[key] = {}
             registry = registry[key]
 
+        if info is None:
+            if name.endswith('*'):
+                # delete all matching entries.
+                for res_name in registry.keys():
+                    if isinstance(registry[res_name], ResourceInfo) and \
+                       res_name.startswith(name[:-1]):
+                        LOG.warn(_('Removing %(item)s from %(path)s') % {
+                            'item': res_name,
+                            'path': descriptive_path})
+                        del registry[res_name]
+            else:
+                # delete this entry.
+                LOG.warn(_('Removing %(item)s from %(path)s') % {
+                    'item': name,
+                    'path': descriptive_path})
+                del registry[name]
+            return
+
         if name in registry and isinstance(registry[name], ResourceInfo):
             details = {
                 'path': descriptive_path,
diff --git a/heat/tests/test_environment.py b/heat/tests/test_environment.py
index 152636efea..c768733eb2 100644
--- a/heat/tests/test_environment.py
+++ b/heat/tests/test_environment.py
@@ -200,3 +200,55 @@ class GlobalEnvLoadingTest(common.HeatTestCase):
         # 3. assert our resource is in place.
         self.assertEqual('file:///not_really_here.yaml',
                          g_env.get_resource_info('OS::Nova::Server').value)
+
+    def test_env_one_resource_disable(self):
+        # prove we can disable a resource in the global environment
+
+        g_env_content = '''
+        resource_registry:
+            "OS::Nova::Server":
+        '''
+        # 1. fake an environment file
+        envdir = self.useFixture(fixtures.TempDir())
+        envfile = os.path.join(envdir.path, 'test.yaml')
+        with open(envfile, 'w+') as ef:
+            ef.write(g_env_content)
+        cfg.CONF.set_override('environment_dir', envdir.path)
+
+        # 2. load global env
+        g_env = environment.Environment({}, user_env=False)
+        resources._load_all(g_env)
+
+        # 3. assert our resource is in now gone.
+        self.assertEqual(None,
+                         g_env.get_resource_info('OS::Nova::Server'))
+
+        # 4. make sure we haven't removed something we shouldn't have
+        self.assertEqual(resources.instance.Instance,
+                         g_env.get_resource_info('AWS::EC2::Instance').value)
+
+    def test_env_multi_resources_disable(self):
+        # prove we can disable resources in the global environment
+
+        g_env_content = '''
+        resource_registry:
+            "AWS::*":
+        '''
+        # 1. fake an environment file
+        envdir = self.useFixture(fixtures.TempDir())
+        envfile = os.path.join(envdir.path, 'test.yaml')
+        with open(envfile, 'w+') as ef:
+            ef.write(g_env_content)
+        cfg.CONF.set_override('environment_dir', envdir.path)
+
+        # 2. load global env
+        g_env = environment.Environment({}, user_env=False)
+        resources._load_all(g_env)
+
+        # 3. assert our resources are now gone.
+        self.assertEqual(None,
+                         g_env.get_resource_info('AWS::EC2::Instance'))
+
+        # 4. make sure we haven't removed something we shouldn't have
+        self.assertEqual(resources.server.Server,
+                         g_env.get_resource_info('OS::Nova::Server').value)