Merge pull request #514 from DavisRayM/circular-reference-error

Fix error encountered while converting multi-language XLSForms to JSON

pyxform/survey_element.py

@@ -219,6 +219,19 @@ def get_abbreviated_xpath(self):
         else:
             return lineage[0].name
 
+    def _delete_keys_from_dict(self, dictionary: dict, keys: list):
+        """
+        Deletes a list of keys from a dictionary.
+        Credits: https://stackoverflow.com/a/49723101
+        """
+        for key in keys:
+            if key in dictionary:
+                del dictionary[key]
+
+        for value in dictionary.values():
+            if isinstance(value, dict):
+                self._delete_keys_from_dict(value, keys)
+
     def to_json_dict(self):
         """
         Create a dict copy of this survey element by removing inappropriate
@@ -227,9 +240,9 @@ def to_json_dict(self):
         self.validate()
         result = self.copy()
         to_delete = ["parent", "question_type_dictionary", "_created"]
-        for key in to_delete:
-            if key in result:
-                del result[key]
+        # Delete all keys that may cause a "Circular Reference"
+        # error while converting the result to JSON
+        self._delete_keys_from_dict(result, to_delete)
         children = result.pop("children")
         result["children"] = []
         for child in children:

pyxform/tests/xform2json_test.py

@@ -9,10 +9,11 @@
 
 from pyxform.builder import create_survey_from_path
 from pyxform.tests import utils
+from pyxform.tests_v1.pyxform_test_case import PyxformTestCase
 from pyxform.xform2json import _try_parse, create_survey_element_from_xml
 
 
-class DumpAndLoadXForm2JsonTests(utils.XFormTestCase):
+class DumpAndLoadXForm2JsonTests(utils.XFormTestCase, PyxformTestCase):
 
     maxDiff = None
 

pyxform/tests_v1/test_xform2json.py

@@ -0,0 +1,43 @@
+# -*- coding: utf-8 -*-
+"""
+Test XForm2JSON functionality
+"""
+import json
+
+from pyxform.builder import create_survey_element_from_dict
+from pyxform.tests_v1.pyxform_test_case import PyxformTestCase
+
+
+class TestXForm2JSON(PyxformTestCase):
+    """
+    Test xform2json module
+    """
+
+    def test_convert_toJSON_multi_language(self):
+        """
+        Test that it's possible to convert XLSForms with multiple languages
+        to JSON and back into XML without losing any of the required information
+        """
+        md = """
+        | survey  |
+        |         | type                   | name  | label:Eng  | label:Fr |
+        |         | text                   | name  | Name       | Prénom   |
+        |         | select_multiple fruits | fruit | Fruit      | Fruit    |
+        |         |                        |       |            |          |
+        | choices | list name              | name  | label:Eng  | label:Fr |
+        |         | fruits                 | 1     | Mango      | Mangue   |
+        |         | fruits                 | 2     | Orange     | Orange   |
+        |         | fruits                 | 3     | Apple      | Pomme    |
+        """
+
+        survey = self.md_to_pyxform_survey(
+            md_raw=md,
+            kwargs={"id_string": "id", "name": "multi-language", "title": "some-title"},
+            autoname=False,
+        )
+        expected_xml = survey.to_xml()
+        generated_json = survey.to_json()
+
+        survey = create_survey_element_from_dict(json.loads(generated_json))
+
+        self.assertEqual(expected_xml, survey.to_xml())