Fix IntegrityError for Orderable translation key on copy (#8321)

tl;dr - EditView builds the page instance from its latest revision and that is what is passed to the form and ultimately submitted.

In order to test the `translation_key`s for orderables, we need to be as close to it as possible, a simple `page.copy()` then `page.save_revision().publish()` doesn't capture the subtleties

Co-authored-by: Kalob Taulien <4743971+KalobTaulien@users.noreply.github.com>

CHANGELOG.txt

@@ -6,6 +6,7 @@ Changelog
 
  * Fix: Allow bulk publishing of pages without revisions (Andy Chosak)
  * Fix: Ensure that all descendant pages are logged when deleting a page, not just immediate children (Jake Howard)
+ * Fix: Translation key `IntegrityError` when publishing pages with translatable `Orderable`s that were copied without being published (Kalob Taulien, Dan Braghis)
 
 
 2.15.4 (11.02.2022)

docs/releases/2.15.5.rst

@@ -15,6 +15,7 @@ Bug fixes
 
  * Allow bulk publishing of pages without revisions (Andy Chosak)
  * Ensure that all descendant pages are logged when deleting a page, not just immediate children (Jake Howard)
+ * Generate new translation keys for translatable ``Orderable`` when page is copied without being published (Kalob Taulien, Dan Braghis)
 
 
 Upgrade considerations

wagtail/admin/tests/pages/test_copy_page.py

@@ -4,7 +4,7 @@ from django.test import TestCase
 from django.urls import reverse
 
 from wagtail.core.models import GroupPagePermission, Page
-from wagtail.tests.testapp.models import SimplePage
+from wagtail.tests.testapp.models import EventPage, EventPageSpeaker, SimplePage
 from wagtail.tests.utils import WagtailTestUtils
 
 
@@ -587,3 +587,57 @@ class TestPageCopy(TestCase, WagtailTestUtils):
 
         # We only need to check that it didn't crash
         self.assertEqual(response.status_code, 302)
+
+    def test_copy_page_with_unique_uuids_in_orderables(self):
+        """
+        Test that a page with orderables can be copied and the translation
+        keys are updated.
+        """
+        event_page = EventPage(
+            title="Moon Landing",
+            location="the moon",
+            audience="public",
+            cost="free on TV",
+            date_from="1969-07-20",
+        )
+        self.root_page.add_child(instance=event_page)
+
+        event_page.speakers.add(
+            EventPageSpeaker(
+                first_name="Neil",
+                last_name="Armstrong",
+            )
+        )
+        # ensure there's a revision (which should capture the new speaker orderables)
+        # before copying the page
+        event_page.save_revision().publish()
+
+        post_data = {
+            "new_title": "New Moon landing",
+            "new_slug": "moon-landing-redux",
+            "new_parent_page": str(self.root_page.id),
+            "copy_subpages": False,
+            "publish_copies": False,
+            "alias": False,
+        }
+        self.client.post(
+            reverse("wagtailadmin_pages:copy", args=[event_page.id]), post_data
+        )
+        new_page = EventPage.objects.last()
+
+        # Hack: get the page instance from the edit form which assembles it from the
+        # latest revision. While we could do new_page.get_latest_revision().as_page_object()
+        # this follow the edit view closer and should it change the test is less
+        # prone to continue working because we're skipping some step
+        response = self.client.get(
+            reverse("wagtailadmin_pages:edit", args=[new_page.id])
+        )
+        new_page_on_edit_form = response.context["form"].instance
+
+        # publish the page, similar to EditView.publish_action()
+        new_page_on_edit_form.save_revision().publish()
+
+        self.assertNotEqual(
+            event_page.speakers.first().translation_key,
+            new_page.speakers.first().translation_key,
+        )

wagtail/core/models/__init__.py

@@ -26,6 +26,7 @@ from django.core.cache import cache
 from django.core.exceptions import PermissionDenied, ValidationError
 from django.core.handlers.base import BaseHandler
 from django.core.handlers.wsgi import WSGIRequest
+from django.core.serializers.json import DjangoJSONEncoder
 from django.db import models, transaction
 from django.db.models import DEFERRED, Q, Value
 from django.db.models.expressions import OuterRef, Subquery
@@ -1584,6 +1585,17 @@ class Page(AbstractPage, index.Indexed, ClusterableModel, metaclass=PageBase):
 
         page_copy, child_object_map = _copy(specific_self, exclude_fields=exclude_fields, update_attrs=base_update_attrs)
 
+        uuid_mapping = {}
+
+        def generate_translation_key(uuid_mapping, old_uuid):
+            """
+            Generates a new UUID based on an old one, then re-uses it
+            """
+            if old_uuid not in uuid_mapping:
+                uuid_mapping[old_uuid] = uuid.uuid4()
+
+            return uuid_mapping[old_uuid]
+
         # Save copied child objects and run process_child_object on them if we need to
         for (child_relation, old_pk), child_object in child_object_map.items():
             if process_child_object:
@@ -1591,7 +1603,7 @@ class Page(AbstractPage, index.Indexed, ClusterableModel, metaclass=PageBase):
 
             # When we're not copying for translation, we should give the translation_key a new value for each child object as well
             if reset_translation_key and isinstance(child_object, TranslatableMixin):
-                child_object.translation_key = uuid.uuid4()
+                child_object.translation_key = generate_translation_key(uuid_mapping, child_object.translation_key)
 
         # Save the new page
         if _mpnode_attrs:
@@ -1642,7 +1654,12 @@ class Page(AbstractPage, index.Indexed, ClusterableModel, metaclass=PageBase):
                         copied_child_object = child_object_map.get((child_relation, child_object['pk']))
                         child_object['pk'] = copied_child_object.pk if copied_child_object else None
 
-                revision.content_json = json.dumps(revision_content)
+                        if reset_translation_key and "translation_key" in child_object:
+                            child_object["translation_key"] = generate_translation_key(
+                                uuid_mapping, child_object["translation_key"]
+                            )
+
+                revision.content_json = json.dumps(revision_content, cls=DjangoJSONEncoder)
 
                 # Save
                 revision.save()