Implement thawing Message from database

lib/nntp/tiny/db.py

@@ -20,6 +20,11 @@ class DatabaseTableCursor():
         return getattr(self.cr, name)
 
     def __map__(self, row):
+        fn = getattr(self.table, '__from_row__', None)
+
+        if fn is not None:
+            return fn(row)
+
         obj = self.table()
 
         for name in self.table.columns:

lib/nntp/tiny/message.py

@@ -49,6 +49,13 @@ class Message(DatabaseTable):
         self.body         = None
         self._key         = None
 
+    @staticmethod
+    def __from_row__(row):
+        message = Message()
+        message.parse(row['content'])
+
+        return message
+
     def __values__(self):
         return (
             self.newsgroup_id,