Merge pull request #2905 from bookwyrm-social/broken-editions

Adds management command to repair editions in bad state

bookwyrm/management/commands/repair_editions.py

@@ -0,0 +1,21 @@
+""" Repair editions with missing works """
+from django.core.management.base import BaseCommand
+from bookwyrm import models
+
+
+class Command(BaseCommand):
+    """command-line options"""
+
+    help = "Repairs an edition that is in a broken state"
+
+    # pylint: disable=unused-argument
+    def handle(self, *args, **options):
+        """Find and repair broken editions"""
+        # Find broken editions
+        editions = models.Edition.objects.filter(parent_work__isnull=True)
+        self.stdout.write(f"Repairing {editions.count()} edition(s):")
+
+        # Do repair
+        for edition in editions:
+            edition.repair()
+            self.stdout.write(".", ending="")

bookwyrm/models/book.py

@@ -381,6 +381,19 @@ class Edition(Book):
 
         return super().save(*args, **kwargs)
 
+    @transaction.atomic
+    def repair(self):
+        """If an edition is in a bad state (missing a work), let's fix that"""
+        # made sure it actually NEEDS reapir
+        if self.parent_work:
+            return
+
+        new_work = Work.objects.create(title=self.title)
+        new_work.authors.set(self.authors.all())
+
+        self.parent_work = new_work
+        self.save(update_fields=["parent_work"], broadcast=False)
+
     @classmethod
     def viewer_aware_objects(cls, viewer):
         """annotate a book query with metadata related to the user"""

bookwyrm/templatetags/rating_tags.py

@@ -12,6 +12,10 @@ register = template.Library()
 @register.filter(name="rating")
 def get_rating(book, user):
     """get the overall rating of a book"""
+    # this shouldn't happen, but it CAN
+    if not book.parent_work:
+        return None
+
     return cache.get_or_set(
         f"book-rating-{book.parent_work.id}",
         lambda u, b: models.Review.objects.filter(

bookwyrm/tests/models/test_book_model.py

@@ -24,8 +24,7 @@ class Book(TestCase):
             title="Example Work", remote_id="https://example.com/book/1"
         )
         self.first_edition = models.Edition.objects.create(
-            title="Example Edition",
-            parent_work=self.work,
+            title="Example Edition", parent_work=self.work
         )
         self.second_edition = models.Edition.objects.create(
             title="Another Example Edition",
@@ -143,3 +142,15 @@ class Book(TestCase):
             for article in articles
         )
         self.assertTrue(all(book.sort_title == "test edition" for book in books))
+
+    def test_repair_edition(self):
+        """Fix editions with no works"""
+        edition = models.Edition.objects.create(title="test")
+        edition.authors.set([models.Author.objects.create(name="Author Name")])
+        self.assertIsNone(edition.parent_work)
+
+        edition.repair()
+        edition.refresh_from_db()
+
+        self.assertEqual(edition.parent_work.title, "test")
+        self.assertEqual(edition.parent_work.authors.count(), 1)

bookwyrm/tests/templatetags/test_rating_tags.py

@@ -71,6 +71,12 @@ class RatingTags(TestCase):
         )
         self.assertEqual(rating_tags.get_rating(self.book, self.local_user), 5)
 
+    def test_get_rating_broken_edition(self, *_):
+        """Don't have a server error if an edition is missing a work"""
+        broken_book = models.Edition.objects.create(title="Test")
+        broken_book.parent_work = None
+        self.assertIsNone(rating_tags.get_rating(broken_book, self.local_user))
+
     def test_get_user_rating(self, *_):
         """get a user's most recent rating of a book"""
         with patch("bookwyrm.models.activitypub_mixin.broadcast_task.apply_async"):