Differentiate works and editions more clearly

fedireads/models/book.py

@@ -84,13 +84,6 @@ class Book(FedireadsModel):
     cover = models.ImageField(upload_to='covers/', blank=True, null=True)
     first_published_date = models.DateTimeField(blank=True, null=True)
     published_date = models.DateTimeField(blank=True, null=True)
-    shelves = models.ManyToManyField(
-        'Shelf',
-        symmetrical=False,
-        through='ShelfBook',
-        through_fields=('book', 'shelf')
-    )
-    parent_work = models.ForeignKey('Work', on_delete=models.PROTECT, null=True)
     objects = InheritanceManager()
 
     @property
@@ -100,6 +93,12 @@ class Book(FedireadsModel):
         model_name = type(self).__name__.lower()
         return '%s/%s/%s' % (base_path, model_name, self.openlibrary_key)
 
+    def save(self, *args, **kwargs):
+        ''' can't be abstract for query reasons, but you shouldn't USE it '''
+        if not isinstance(self, Edition) and not isinstance(self, Work):
+            raise ValueError('Books should be added as Editions or Works')
+        super().save(*args, **kwargs)
+
     def __repr__(self):
         return "<{} key={!r} title={!r}>".format(
             self.__class__,
@@ -125,6 +124,13 @@ class Edition(Book):
     publishers = ArrayField(
         models.CharField(max_length=255), blank=True, default=list
     )
+    shelves = models.ManyToManyField(
+        'Shelf',
+        symmetrical=False,
+        through='ShelfBook',
+        through_fields=('book', 'shelf')
+    )
+    parent_work = models.ForeignKey('Work', on_delete=models.PROTECT, null=True)
 
 
 class Author(FedireadsModel):

fedireads/models/shelf.py

@@ -10,7 +10,7 @@ class Shelf(FedireadsModel):
     user = models.ForeignKey('User', on_delete=models.PROTECT)
     editable = models.BooleanField(default=True)
     books = models.ManyToManyField(
-        'Book',
+        'Edition',
         symmetrical=False,
         through='ShelfBook',
         through_fields=('shelf', 'book')
@@ -29,7 +29,7 @@ class Shelf(FedireadsModel):
 
 class ShelfBook(FedireadsModel):
     # many to many join table for books and shelves
-    book = models.ForeignKey('Book', on_delete=models.PROTECT)
+    book = models.ForeignKey('Edition', on_delete=models.PROTECT)
     shelf = models.ForeignKey('Shelf', on_delete=models.PROTECT)
     added_by = models.ForeignKey(
         'User',

fedireads/models/status.py

@@ -15,7 +15,7 @@ class Status(FedireadsModel):
     status_type = models.CharField(max_length=255, default='Note')
     content = models.TextField(blank=True, null=True)
     mention_users = models.ManyToManyField('User', related_name='mention_user')
-    mention_books = models.ManyToManyField('Book', related_name='mention_book')
+    mention_books = models.ManyToManyField('Edition', related_name='mention_book')
     activity_type = models.CharField(max_length=255, default='Note')
     local = models.BooleanField(default=True)
     privacy = models.CharField(max_length=255, default='public')
@@ -49,7 +49,7 @@ class Status(FedireadsModel):
 class Comment(Status):
     ''' like a review but without a rating and transient '''
     name = models.CharField(max_length=255)
-    book = models.ForeignKey('Book', on_delete=models.PROTECT)
+    book = models.ForeignKey('Edition', on_delete=models.PROTECT)
 
     def save(self, *args, **kwargs):
         self.status_type = 'Comment'
@@ -60,7 +60,7 @@ class Comment(Status):
 class Review(Status):
     ''' a book review '''
     name = models.CharField(max_length=255)
-    book = models.ForeignKey('Book', on_delete=models.PROTECT)
+    book = models.ForeignKey('Edition', on_delete=models.PROTECT)
     rating = models.IntegerField(
         default=0,
         validators=[MinValueValidator(0), MaxValueValidator(5)]
@@ -92,7 +92,7 @@ class Favorite(FedireadsModel):
 class Tag(FedireadsModel):
     ''' freeform tags for books '''
     user = models.ForeignKey('User', on_delete=models.PROTECT)
-    book = models.ForeignKey('Book', on_delete=models.PROTECT)
+    book = models.ForeignKey('Edition', on_delete=models.PROTECT)
     name = models.CharField(max_length=100)
     identifier = models.CharField(max_length=100)
 
@@ -113,7 +113,7 @@ class Notification(FedireadsModel):
     ''' you've been tagged, liked, followed, etc '''
     user = models.ForeignKey('User', on_delete=models.PROTECT)
     related_book = models.ForeignKey(
-        'Book', on_delete=models.PROTECT, null=True)
+        'Edition', on_delete=models.PROTECT, null=True)
     related_user = models.ForeignKey(
         'User',
         on_delete=models.PROTECT, null=True, related_name='related_user')