Add method to repair media::file problems (#322)

This needs to be applied to existing content

src/formpack/utils/bugfix.py

@@ -0,0 +1,78 @@
+# coding: utf-8
+
+from copy import deepcopy
+
+from ..constants import UNTRANSLATED
+
+
+def repair_file_column_content_in_place(content) -> bool:
+    """
+    #321 introduced a bug where the `file` column gets renamed to `media::file`
+    and treated as a translatable column (see #322). This function repairs that
+    damage.
+
+    This function is intended to be run by KPI, which should it to correct
+    `Asset` and `AssetVersion` content.
+
+    Returns `True` if any change was made
+    """
+
+    # Store updates and apply them to `content` only of all conditions are met
+    updates = {}
+
+    try:
+        for key in 'translated', 'translations', 'survey':
+            updates[key] = deepcopy(content[key])
+    except KeyError:
+        # Do not proceed if content is incomplete
+        return False
+
+    try:
+        updates['translated'].remove('media::file')
+    except ValueError:
+        # The invalid column `media::file` inside `translated` is a hallmark of
+        # the problem this method is intended to fix. Do not proceed if it was
+        # not found
+        return False
+
+    max_label_list_length = 0
+    any_row_fixed = False
+    for row in updates['survey']:
+        max_label_list_length = max(
+            max_label_list_length, len(row.get('label', []))
+        )
+        bad_file_col = row.get('media::file')
+        if not bad_file_col:
+            continue
+        if not isinstance(bad_file_col, list):
+            # All problems of our own making (#322) will result in
+            # `media::file` being a list (or array when JSON)
+            continue
+        for val in bad_file_col:
+            if val is not None:
+                row['file'] = val
+                del row['media::file']
+                any_row_fixed = True
+                break
+    if not any_row_fixed:
+        return False
+
+    # Multi-language forms need an additional fix to remove a superfluous null
+    # translation added by the bogus `media::file` column
+    if len(updates['translations']) > max_label_list_length:
+        labels_translations_mismatch = True
+        if len(updates['translations']) == max_label_list_length + 1:
+            try:
+                updates['translations'].remove(UNTRANSLATED)
+            except ValueError:
+                pass
+            else:
+                labels_translations_mismatch = False  # Fixed it!
+        if labels_translations_mismatch:
+            # This form has uncorrected problems. Bail out instead of modifying
+            # it at all
+            return False
+
+    # Success! Apply updates to the original content
+    content.update(updates)
+    return True

tests/test_bugfix.py

@@ -0,0 +1,38 @@
+# coding: utf-8
+
+from formpack.utils.bugfix import repair_file_column_content_in_place
+
+
+def test_repair_file_column():
+    content = {
+        'schema': '1',
+        'settings': {},
+        'survey': [
+            {
+                '$kuid': 'qt1C9CFUj',
+                '$qpath': 'interviewer_name_text',
+                '$xpath': 'interviewer_name_text',
+                'label': [
+                    "Введіть ім'я співробітника:",
+                    "Enter interviewer's name",
+                ],
+                'name': 'interviewer_name_text',
+                'type': 'text',
+            },
+            {
+                '$kuid': 'bHGP1YkRq',
+                '$qpath': 'oblast',
+                '$xpath': 'oblast',
+                'label': ['Область', 'Oblast'],
+                'media::file': [None, None, 'oblast.csv'],
+                'name': 'oblast',
+                'type': 'select_one_from_file',
+            },
+        ],
+        'translated': ['label', 'media::file'],
+        'translations': ['Ukrainian', 'English', None],
+    }
+    assert repair_file_column_content_in_place(content)
+    assert content['survey'][1]['file'] == 'oblast.csv'
+    assert content['translated'] == ['label']
+    assert content['translations'] == ['Ukrainian', 'English']