recipe/request: do not propagate the request destroyed state

Prevent unexpected instance deletion.

slapos/recipe/request.py

@@ -88,7 +88,9 @@ class Recipe(object):
       Possible names depend on requested partition's software type.
 
     state (optional)
-     Requested state, default value is the state of the requester.
+     Requested state, default value is "started", except the state of
+     the requester is "stopped" (which changes the default value to
+     "stopped").
 
     Output:
       See "return" input key.
@@ -120,8 +122,13 @@ class Recipe(object):
     slave = options.get('slave', 'false').lower() in \
       librecipe.GenericBaseRecipe.TRUE_VALUES
 
-    # By default XXXX Way of doing it is ugly and dangerous
-    requested_state = options.get('state', buildout['slap-connection'].get('requested','started'))
+    # By default, propagate the state of the parent instance
+    # Except if parent is destroyed, as it may lead to the unexpected
+    # destruction of the full instance tree
+    default_state = buildout['slap-connection'].get('requested', 'started')
+    if default_state not in ('started', 'stopped'):
+      default_state = 'started'
+    requested_state = options.get('state', default_state)
     options['requested-state'] = requested_state
 
     slap = slapmodule.slap()

slapos/test/recipe/test_request.py

@@ -89,6 +89,35 @@ class RecipeTestMixin(object):
       partition_parameter_kw=self.called_partition_parameter_kw,
       shared=False, state='started')
 
+  def test_requester_stopped_state_propagated(self):
+    options = defaultdict(str)
+    options['return'] = 'anything'
+    self.buildout['slap-connection']['requested'] = 'stopped'
+
+    self.instance_getConnectionParameter.return_value = self.return_value_empty
+
+    with LogCapture() as log:
+      self.recipe(self.buildout, "request", options)
+    log.check()
+    self.request_instance.assert_called_with(
+      '', 'RootSoftwareInstance', '', filter_kw={},
+      partition_parameter_kw=self.called_partition_parameter_kw,
+      shared=False, state='stopped')
+
+  def test_requester_destroyed_state_not_propagated(self):
+    options = defaultdict(str)
+    options['return'] = 'anything'
+    self.buildout['slap-connection']['requested'] = 'destroyed'
+
+    self.instance_getConnectionParameter.return_value = self.return_value_empty
+
+    with LogCapture() as log:
+      self.recipe(self.buildout, "request", options)
+    log.check()
+    self.request_instance.assert_called_with(
+      '', 'RootSoftwareInstance', '', filter_kw={},
+      partition_parameter_kw=self.called_partition_parameter_kw,
+      shared=False, state='started')
 
 class RecipeTest(RecipeTestMixin, unittest.TestCase):
   recipe = request.Recipe