Merge pull request #70 from NextThought/auto-anon-dict-fields

InterfaceObjectIO uses its newfound powers to make Dict fields internalize easier

CHANGES.rst

@@ -53,6 +53,12 @@
   `PR 68
   <https://github.com/NextThought/nti.externalization/pull/68>`_.
 
+- Schemas that use ``InterfaceObjectIO`` (including through the ZCML
+  directive ``registerAutoPackageIO``) can use ``Dict`` fields more
+  easily on internalization (externalization has always worked): They
+  automatically internalize their values by treating the ``Dict`` as
+  anonymous external data.
+
 1.0.0a2 (2018-07-05)
 ====================
 

src/nti/externalization/_datastructures.pxd

@@ -28,6 +28,8 @@ cdef make_repr
 cdef isSyntheticKey
 cdef find_most_derived_interface
 cdef NotGiven
+cdef IDict_providedBy
+cdef _anonymous_dict_factory
 
 cdef class ExternalizableDictionaryMixin(object):
     # This is a mixin used with other C base classes (E.g., persistent)

src/nti/externalization/datastructures.py

@@ -22,6 +22,7 @@
 from zope import interface
 from zope import schema
 from zope.schema.interfaces import SchemaNotProvided
+from zope.schema.interfaces import IDict
 
 from nti.schema.interfaces import find_most_derived_interface
 
@@ -39,6 +40,7 @@
 from .internalization import validate_named_field_value
 from .internalization.factories import find_factory_for
 from .representation import make_repr
+from .factory import AnonymousObjectFactory
 
 from ._base_interfaces import get_standard_external_fields
 from ._base_interfaces import get_standard_internal_fields
@@ -48,6 +50,7 @@
 
 StandardExternalFields = get_standard_external_fields()
 StandardInternalFields = get_standard_internal_fields()
+IDict_providedBy = IDict.providedBy
 
 __all__ = [
     'ExternalizableDictionaryMixin',
@@ -330,6 +333,8 @@ def _ext_accept_update_key(self, k, ext_self, ext_keys):
 
 _primitives = six.string_types + (numbers.Number, bool)
 
+_anonymous_dict_factory = AnonymousObjectFactory(lambda x: x)
+_anonymous_dict_factory.__external_factory_wants_arg__ = True
 
 class InterfaceObjectIO(AbstractDynamicObjectIO):
     """
@@ -510,11 +515,14 @@ def find_factory_for_named_value(self, key, value, registry):
                 # Anything else is a programming error.
                 if isinstance(factory, str):
                     factory = registry.getUtility(IAnonymousObjectFactory, factory)
-            # TODO: If there is no factory found, check to see if the
-            # schema field is a Dict with a complex value type, and if
-            # so, automatically update it in place? This currently
-            # requires the user use a ZCML directive for each such
-            # dict field.
+
+                if factory is None and IDict_providedBy(field) and isinstance(value, dict):
+                    # If is no factory found, check to see if the
+                    # schema field is a Dict with a complex value type, and if
+                    # so, automatically update it in place. The alternative
+                    # requires the user to use a ZCML directive for each such
+                    # dict field.
+                    factory = _anonymous_dict_factory
         return factory
 
     def updateFromExternalObject(self, parsed, *unused_args, **unused_kwargs):

src/nti/externalization/tests/benchmarks/configure.zcml

@@ -13,9 +13,4 @@
 		modules=".objects"
 		/>
 
-    <ext:anonymousObjectFactoryInPlace
-        for=".interfaces.IUserContactProfile"
-        field="addresses"
-        />
-
 </configure>