Make the ActionContext serializable

Currently if Mistral needs to pass the ActionContext  via it's internal
rpc calls it wont be serialised. This change should have no end-user
impact, but makes it easier for Mistral to use internally.

Change-Id: I238355d52c77d622740527e43ddb2b7484cc58db

mistral_lib/actions/context.py

@@ -12,8 +12,10 @@
 
 import warnings
 
+from mistral_lib import serialization
 
-class ActionContext(object):
+
+class ActionContext(serialization.MistralSerializable):
 
     def __init__(self, security_ctx=None, execution_ctx=None):
         self.security = security_ctx
@@ -86,3 +88,19 @@ class ExecutionContext(object):
     def task_id(self):
         self._deprecate_task_id_warning()
         return self.task_execution_id
+
+
+class ActionContextSerializer(serialization.DictBasedSerializer):
+    def serialize_to_dict(self, entity):
+        return {
+            'security': vars(entity.security),
+            'execution': vars(entity.execution),
+        }
+
+    def deserialize_from_dict(self, entity_dict):
+        return ActionContext(
+            security_ctx=SecurityContext(**entity_dict['security']),
+            execution_ctx=ExecutionContext(**entity_dict['execution'])
+        )
+
+serialization.register_serializer(ActionContext, ActionContextSerializer())

mistral_lib/tests/actions/test_context.py

@@ -69,3 +69,27 @@ class TestActionsBase(tests_base.TestCase):
             old = getattr(ctx, deprecated)
             new = getattr(ctx.security, deprecated)
             self.assertEqual(old, new)
+
+
+class TestActionContextSerializer(tests_base.TestCase):
+
+    def test_serialization(self):
+
+        ctx = _fake_context()
+        serialiser = context.ActionContextSerializer()
+        dict_ctx = serialiser.serialize_to_dict(ctx)
+
+        self.assertEqual(dict_ctx['security'], vars(ctx.security))
+        self.assertEqual(dict_ctx['execution'], vars(ctx.execution))
+
+    def test_deserialization(self):
+
+        ctx = _fake_context()
+        serialiser = context.ActionContextSerializer()
+        dict_ctx = serialiser.serialize_to_dict(ctx)
+        ctx_2 = serialiser.deserialize_from_dict(dict_ctx)
+
+        self.assertEqual(ctx.security.auth_uri, ctx_2.security.auth_uri)
+        self.assertEqual(
+            ctx.execution.workflow_name,
+            ctx_2.execution.workflow_name)