workflows: update export to models for py3 (#36515)

tests/test_form_pages.py

@@ -3321,7 +3321,7 @@ def test_formdata_generated_document_odt_download(pub, odt_template):
     with open(os.path.join(os.path.dirname(__file__), 'template-out.odt'), 'rb') as f:
         body = resp.click(odt_template, index=0).follow().body
         assert_equal_zip(BytesIO(body), f)
-    assert resp.click('test.rtf', index=0).follow().body == 'HELLO NEW WORLD'
+    assert resp.click('test.rtf', index=0).follow().body == b'HELLO NEW WORLD'
 
 def test_formdata_generated_document_odt_download_with_substitution_variable(pub):
     create_user_and_admin(pub)
@@ -3399,7 +3399,7 @@ def test_formdata_generated_document_odt_download_with_substitution_variable(pub
         body = resp.click('template.odt', index=0).follow().body
         assert_equal_zip(BytesIO(body), f)
     response2 = resp.click('test.rtf', index=0).follow()
-    assert response2.body == 'HELLO NEW WORLD'
+    assert response2.body == b'HELLO NEW WORLD'
     # Test attachment substitution variables
     variables = formdef.data_class().select()[0].get_substitution_variables()
     assert 'attachments' in variables

wcs/wf/export_to_model.py

@@ -23,6 +23,7 @@ import subprocess
 import tempfile
 import shutil
 
+from django.utils import six
 from django.utils.encoding import force_bytes, force_text
 from django.utils.six import BytesIO, StringIO
 
@@ -403,11 +404,11 @@ class ExportToModel(WorkflowStatusItem):
         try:
             # force ezt_only=True because an RTF file may contain {{ characters
             # and would be seen as a Django template
-            return StringIO(template_on_formdata(
+            return BytesIO(force_bytes(template_on_formdata(
                 formdata,
                 force_text(self.model_file.get_file().read()),
                 ezt_format=ezt.FORMAT_RTF,
-                ezt_only=True))
+                ezt_only=True)))
         except TemplateError as e:
             url = formdata.get_url()
             get_logger().error('error in template for export to model [%s]: %s' % (url, str(e)))
@@ -463,11 +464,17 @@ class ExportToModel(WorkflowStatusItem):
                     # we would also need to copy its style and what not).
                     current_tail = node.tail or ''
                     node.tail = None
-                    as_str = ET.tostring(node).replace('\n\n',
+                    as_str = force_str(ET.tostring(node)).replace('\n\n',
                             2 * ('<nsa:line-break xmlns:nsa="%(ns)s"/>' % {'ns': OO_TEXT_NS}))
                     as_node = ET.fromstring(as_str)
                     node.text = as_node.text
-                    node._children = as_node._children
+                    if six.PY2:
+                        node._children = as_node._children
+                    else:
+                        for child in node.getchildren():
+                            node.remove(child)
+                        for child in as_node.getchildren():
+                            node.append(child)
                     node.tail = current_tail
 
         outstream = BytesIO()