Adds ReviewRating model

I can't just calling Rating because that would clash with the rating
field

bookwyrm/activitypub/__init__.py

@@ -6,7 +6,8 @@ from .base_activity import ActivityEncoder, Signature
 from .base_activity import Link, Mention
 from .base_activity import ActivitySerializerError, resolve_remote_id
 from .image import Image
-from .note import Note, GeneratedNote, Article, Comment, Review, Quotation
+from .note import Note, GeneratedNote, Article, Comment, Quotation
+from .note import Review, Rating
 from .note import Tombstone
 from .interaction import Boost, Like
 from .ordered_collection import OrderedCollection, OrderedCollectionPage

bookwyrm/activitypub/note.py

@@ -50,6 +50,13 @@ class Comment(Note):
     type: str = 'Comment'
 
 
+@dataclass(init=False)
+class Quotation(Comment):
+    ''' a quote and commentary on a book '''
+    quote: str
+    type: str = 'Quotation'
+
+
 @dataclass(init=False)
 class Review(Comment):
     ''' a full book review '''
@@ -59,7 +66,8 @@ class Review(Comment):
 
 
 @dataclass(init=False)
-class Quotation(Comment):
-    ''' a quote and commentary on a book '''
-    quote: str
-    type: str = 'Quotation'
+class Rating(Comment):
+    ''' a full book review '''
+    rating: int = None
+    content: str = None
+    type: str = 'Rating'

bookwyrm/forms.py

@@ -54,8 +54,8 @@ class RegisterForm(CustomForm):
 
 class RatingForm(CustomForm):
     class Meta:
-        model = models.Review
-        fields = ['user', 'book', 'content', 'rating', 'privacy']
+        model = models.ReviewRating
+        fields = ['user', 'book', 'rating', 'privacy']
 
 
 class ReviewForm(CustomForm):

bookwyrm/migrations/0030_reviewrating.py

@@ -0,0 +1,52 @@
+# Generated by Django 3.0.7 on 2021-01-01 19:05
+
+from django.db.models.fields.reverse_related import ManyToOneRel
+from django.db.models import Q
+from django.db import migrations, models
+import django.db.models.deletion
+from bookwyrm.management.commands.deduplicate_book_data import update_related
+
+
+def convert_review_rating(app_registry, schema_editor):
+    ''' take reviews with no content and turn them into ratings '''
+    db_alias = schema_editor.connection.alias
+    reviews = app_registry.get_model('bookwyrm', 'Review')
+    review_ratings = app_registry.get_model('bookwyrm', 'ReviewRating')
+    ratings = reviews.objects.using(db_alias).filter(
+        Q(content__isnull=True) | Q(content=''))
+    # replace the old review with the rating
+    for review in ratings:
+        rating = review_ratings.objects.create(
+            user=review.user, rating=review.rating, book=review.book)
+        for field in review._meta.get_fields():
+            if isinstance(field, ManyToOneRel) or field.name == 'status_ptr':
+                continue
+            value = getattr(review, field.name)
+            print(review, rating, field.name, value)
+            try:
+                setattr(rating, field.name, value)
+            except TypeError:
+                getattr(rating, field.name).set(value.all())
+        rating.save()
+        update_related(rating, review)
+        review.delete()
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('bookwyrm', '0029_auto_20201221_2014'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='ReviewRating',
+            fields=[
+                ('review_ptr', models.OneToOneField(auto_created=True, on_delete=django.db.models.deletion.CASCADE, parent_link=True, primary_key=True, serialize=False, to='bookwyrm.Review')),
+            ],
+            options={
+                'abstract': False,
+            },
+            bases=('bookwyrm.review',),
+        ),
+        migrations.RunPython(convert_review_rating),
+    ]

bookwyrm/models/__init__.py

@@ -8,7 +8,8 @@ from .connector import Connector
 
 from .shelf import Shelf, ShelfBook
 
-from .status import Status, GeneratedNote, Review, Comment, Quotation
+from .status import Status, GeneratedNote, Comment, Quotation
+from .status import Review, ReviewRating
 from .status import Boost
 from .attachment import Image
 from .favorite import Favorite

bookwyrm/models/status.py

@@ -222,6 +222,22 @@ class Review(Status):
     pure_type = 'Article'
 
 
+class ReviewRating(Review):
+    ''' a subtype of review that only contains a rating '''
+    def save(self, *args, **kwargs):
+        if not self.rating:
+            raise ValueError('Rating object must include a numerical rating')
+        return super().save(*args, **kwargs)
+
+    @property
+    def pure_content(self):
+        #pylint: disable=bad-string-format-type
+        return 'Rated "%s": %d' % (self.book.title, self.rating)
+
+    activity_serializer = activitypub.Rating
+    pure_type = 'Note'
+
+
 class Boost(Status):
     ''' boost'ing a post '''
     boosted_status = fields.ForeignKey(