Add better support for "make import batch from file" pattern

tailbone/forms/__init__.py

@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  Rattail -- Retail Software Framework
-#  Copyright © 2010-2017 Lance Edgar
+#  Copyright © 2010-2018 Lance Edgar
 #
 #  This file is part of Rattail.
 #
@@ -28,4 +28,4 @@ from __future__ import unicode_literals, absolute_import
 
 from . import types
 from . import widgets
-from .core import Form
+from .core import Form, SimpleFileImport

tailbone/forms/core.py

@@ -881,3 +881,21 @@ class FieldList(list):
     def insert_after(self, field, newfield):
         i = self.index(field)
         self.insert(i + 1, newfield)
+
+
+@colander.deferred
+def upload_widget(node, kw):
+    request = kw['request']
+    tmpstore = SessionFileUploadTempStore(request)
+    return dfwidget.FileUploadWidget(tmpstore)
+
+
+class SimpleFileImport(colander.Schema):
+    """
+    Schema for simple file import.  Note that you must bind your ``request``
+    object to this schema, i.e.::
+
+       schema = SimpleFileImport().bind(request=request)
+    """
+    filename = colander.SchemaNode(deform.FileData(),
+                                   widget=upload_widget)