messaging: Provide metadata for messages

leapp/messaging/__init__.py

@@ -189,4 +189,4 @@ def consume(self, actor, *types):
         if types:
             filtered = set(requested.__name__ for requested in types)
             messages = [message for message in messages if message['type'] in filtered]
-        return (lookup[message['type']].create(json.loads(message['message']['data'])) for message in messages)
+        return (lookup[msg['type']].create(msg, json.loads(msg['message']['data'])) for msg in messages)

leapp/models/__init__.py

@@ -71,14 +71,50 @@ def __init__(cls, name, bases, attrs):
         super(ModelMeta, cls).__init__(name, bases, attrs)
 
 
+class MetaData(object):
+    def __init__(self, data):
+        self._data = data
+
+    @property
+    def row_id(self):
+        """ Returns the row id of the message in the message table.  """
+        return self._data.get('id')
+
+    @property
+    def actor(self):
+        """ Returns the name of the actor that has sent this message.  """
+        return self._data.get('actor')
+
+    @property
+    def phase(self):
+        """ Returns the name of the phase in which this message has been sent.  """
+        return self._data.get('phase')
+
+    @property
+    def timestamp(self):
+        """ Returns the timestamp string in ISO formst from when this message has been sent.  """
+        return self._data.get('stamp')
+
+    @property
+    def topic(self):
+        """ Returns the name of the topic of this message. """
+        return self._data.get('topic')
+
+    @property
+    def hostname(self):
+        """ Returns the name of the host (FQDN) from where this message originates. """
+        return self._data.get('hostname')
+
+
 class Model(with_metaclass(ModelMeta)):
     """
     Model is a base class for all models.
 
     Models are defining the data structure of the payload of messages and the
     metadata required, such as a name and topic.
     """
-    def __init__(self, init_method='from_initialization', **kwargs):
+    def __init__(self, metadata=None, init_method='from_initialization', **kwargs):
+        self._metadata = MetaData(metadata or {})
         super(Model, self).__init__()
         defined_fields = type(self).fields
         for key in kwargs.keys():
@@ -101,16 +137,25 @@ def __init__(self, init_method='from_initialization', **kwargs):
     Note: Dynamically added fields are ignored by the framework.
     """
 
+    def message_metadata(self):
+        """
+        Provides the message meta data of a message.
+
+        :returns: An instance of :py:class:`leapp.models.MetaData` or None
+        :rtype: :py:class:`leapp.models.MetaData` or `NoneType`
+        """
+        return self._metadata
+
     @classmethod
-    def create(cls, data):
+    def create(cls, metadata, data):
         """
         Create an instance of this class and use the data to initialize the fields within.
 
         :param data: Data to initialize the Model from deserialized data
         :type data: dict
         :return: Instance of this class
         """
-        return cls(init_method='to_model', **data)
+        return cls(metadata=metadata, init_method='to_model', **data)
 
     def dump(self):
         """

tests/scripts/test_serialization.py

@@ -70,13 +70,13 @@ def test_base_usage():
 
 def test_basic_model():
     m = BasicModel(message='Some message')
-    m2 = BasicModel.create(m.dump())
+    m2 = BasicModel.create(None, m.dump())
     assert m.message == m2.message
 
 
 def test_string_list_model():
     m = WithStringListModel(messages=['Some message'])
-    m2 = WithStringListModel.create(m.dump())
+    m2 = WithStringListModel.create(None, m.dump())
     assert m.messages == m2.messages
     m2.messages = 'str'
 
@@ -98,7 +98,7 @@ def test_string_fields_violations():
 
 def test_nested_model():
     m = WithNestedModel(basic=BasicModel(message='Some message'))
-    m2 = WithNestedModel.create(m.dump())
+    m2 = WithNestedModel.create(None, m.dump())
     assert m.basic == m2.basic
 
     with pytest.raises(fields.ModelMisuseError):
@@ -120,24 +120,24 @@ def test_nested_model():
         x.dump()
 
     with pytest.raises(fields.ModelViolationError):
-        WithNestedModel.create(dict(basic=None))
+        WithNestedModel.create(None, dict(basic=None))
 
     with pytest.raises(fields.ModelViolationError):
         WithNestedModel(basic=None)
 
-    assert WithNestedModel.create({'basic': {'message': 'test-message'}}).basic.message == 'test-message'
+    assert WithNestedModel.create(None, {'basic': {'message': 'test-message'}}).basic.message == 'test-message'
     assert WithNestedModel(basic=BasicModel(message='test-message')).basic.message == 'test-message'
 
 
 def test_nested_list_model():
     m = WithNestedListModel(items=[BasicModel(message='Some message')])
-    m2 = WithNestedListModel.create(m.dump())
+    m2 = WithNestedListModel.create(None, m.dump())
     assert m.items == m2.items
 
 
 def test_field_types():
     m = AllFieldTypesModel()
-    m2 = AllFieldTypesModel.create(m.dump())
+    m2 = AllFieldTypesModel.create(None, m.dump())
     assert m == m2