if config_extra_fields == 'ignore', store extra fields in the object …

…so they can be viewed and saved later if the object is saved

mongoalchemy/document.py

@@ -110,6 +110,8 @@ def __init__(self, retrieved_fields=None, **kwargs):
         self.partial = retrieved_fields != None
         self.retrieved_fields = self.__normalize(retrieved_fields)
 
+        self.__extra_fields = {}
+
         cls = self.__class__
 
         fields = self.get_fields()
@@ -130,11 +132,13 @@ def __init__(self, retrieved_fields=None, **kwargs):
 
             if hasattr(field, 'default'):
                 setattr(self, name, field.default)
-
-        if self.config_extra_fields != 'ignore':
+
             for k in kwargs:
                 if k not in fields:
-                    raise ExtraValueException(k)
+                    if self.config_extra_fields == 'ignore':
+                        self.__extra_fields[k] = kwargs[k]
+                    else:
+                        raise ExtraValueException(k)
 
     def __setattr__(self, name, value):
         cls = self.__class__
@@ -172,6 +176,9 @@ def __getattribute__(self, name):
     
     '''
 
+    def get_extra_fields(self):
+        return self.__extra_fields
+
     @classmethod
     def get_fields(cls):
         '''Returns a dict mapping the names of the fields in a document 
@@ -247,6 +254,8 @@ def wrap(self):
             be saved into a mongo database.  This is done by using the ``wrap()``
             methods of the underlying fields to set values.'''
         res = {}
+        for k, v in self.__extra_fields.iteritems():
+            res[k] = v
         cls = self.__class__
         for name in dir(cls):
             field = getattr(cls, name)
@@ -287,6 +296,9 @@ def unwrap(cls, obj, fields=None):
         params = {}
         for k, v in obj.iteritems():
             k = name_reverse.get(k, k)
+            if not hasattr(cls, k) and cls.config_extra_fields:
+                params[str(k)] = v
+                continue
             field = getattr(cls, k)
             if fields != None and isinstance(field, DocumentField):
                 normalized_fields = cls.__normalize(fields)

test/test_documents.py

@@ -53,6 +53,16 @@ def bad_extra_fields_param_test():
     class BadDoc(Document):
         config_extra_fields = 'blah'
 
+def extra_fields_test():
+    class BadDoc(Document):
+        config_extra_fields = 'ignore'
+    doc_with_extra = {'foo' : [1]}
+
+    unwrapped = BadDoc.unwrap(doc_with_extra)
+    assert unwrapped.get_extra_fields() == doc_with_extra
+
+    assert BadDoc.wrap(unwrapped) == doc_with_extra
+
 
 @raises(MissingValueException)
 def test_required_fields():