add Part._before_marshal()

Steve Canny · Steve Canny · commit e1927e5588cc · 2013-08-05T15:08:41.000-07:00
diff --git a/opc/package.py b/opc/package.py
@@ -150,6 +150,16 @@ def _after_unmarshal(self):
         # subclass
         pass
 
+    def _before_marshal(self):
+        """
+        Entry point for pre-serialization processing, for example to finalize
+        part naming if necessary. May be overridden by subclasses without
+        forwarding call to super.
+        """
+        # don't place any code here, just catch call if not overridden by
+        # subclass
+        pass
+
 
 class PartFactory(object):
     """
diff --git a/opc/pkgwriter.py b/opc/pkgwriter.py
@@ -27,3 +27,4 @@ def write(pkg_file, pkg_rels, parts):
         *pkg_rels* and *parts* and a content types stream based on the
         content types of the parts.
         """
+        raise NotImplementedError()
diff --git a/tests/test_package.py b/tests/test_package.py
@@ -169,6 +169,9 @@ def it_can_add_a_relationship_to_another_part(self, part):
     def it_can_be_notified_after_unmarshalling_is_complete(self, part):
         part._after_unmarshal()
 
+    def it_can_be_notified_before_marshalling_is_started(self, part):
+        part._before_marshal()
+
 
 class DescribePartFactory(object):
 
