spike: [nomerge] spike on restricted run modeling

enterprise_catalog/apps/catalog/admin.py

@@ -15,6 +15,10 @@
     ContentMetadata,
     EnterpriseCatalog,
     EnterpriseCatalogRoleAssignment,
+    Library,
+    Book,
+    BookSpecialCopies,
+    RestrictedBook,
 )
 
 
@@ -167,3 +171,36 @@ class Meta:
 
     fields = ('user', 'role', 'enterprise_id', 'applies_to_all_contexts')
     form = EnterpriseCatalogRoleAssignmentAdminForm
+
+
+@admin.register(Library)
+class LibraryAdmin(admin.ModelAdmin):
+    """
+    """
+
+@admin.register(Book)
+class BookAdmin(admin.ModelAdmin):
+    """
+    """
+
+@admin.register(BookSpecialCopies)
+class BookAdmin(admin.ModelAdmin):
+    """
+    """
+
+@admin.register(RestrictedBook)
+class RestrictedBookAdmin(admin.ModelAdmin):
+    """
+    """
+    list_display = [
+        'parent',
+        'library',
+        'data',
+    ]
+
+    fields = [
+        'parent',
+        'library',
+        'data',
+        'title',
+    ]

enterprise_catalog/apps/catalog/migrations/0040_spike.py

@@ -0,0 +1,55 @@
+# Generated by Django 4.2.15 on 2024-09-26 14:33
+
+import collections
+from django.db import migrations, models
+import django.db.models.deletion
+import jsonfield.encoder
+import jsonfield.fields
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('catalog', '0039_alter_catalogquery_unique_together_and_more'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Book',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('title', models.CharField(max_length=255, unique=True)),
+                ('data', jsonfield.fields.JSONField(blank=True, default={}, dump_kwargs={'cls': jsonfield.encoder.JSONEncoder, 'indent': 4, 'separators': (',', ':')}, load_kwargs={'object_pairs_hook': collections.OrderedDict}, null=True)),
+            ],
+        ),
+        migrations.CreateModel(
+            name='BookSpecialCopies',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('book', models.OneToOneField(on_delete=django.db.models.deletion.CASCADE, related_name='special_copies', to='catalog.book')),
+            ],
+        ),
+        migrations.CreateModel(
+            name='Library',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('name', models.CharField(max_length=255, unique=True)),
+            ],
+        ),
+        migrations.CreateModel(
+            name='RestrictedBook',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('title', models.CharField(max_length=255, unique=True)),
+                ('data', jsonfield.fields.JSONField(blank=True, default={}, dump_kwargs={'cls': jsonfield.encoder.JSONEncoder, 'indent': 4, 'separators': (',', ':')}, load_kwargs={'object_pairs_hook': collections.OrderedDict}, null=True)),
+                ('libraries', models.ManyToManyField(to='catalog.library')),
+                ('library', models.ForeignKey(null=True, on_delete=django.db.models.deletion.CASCADE, related_name='special_copies', to='catalog.library')),
+                ('parent', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='catalog.bookspecialcopies')),
+            ],
+        ),
+        migrations.AddField(
+            model_name='book',
+            name='libraries',
+            field=models.ManyToManyField(to='catalog.library'),
+        ),
+    ]

enterprise_catalog/apps/catalog/models.py

@@ -1197,3 +1197,108 @@ def current_options(cls):
                 'no_async': current_config.no_async,
             }
         return {}
+
+
+class Library(models.Model):
+    class Meta:
+        app_label = 'catalog'
+
+    name = models.CharField(
+        max_length=255,
+        blank=False,
+        null=False,
+        unique=True,
+    )
+
+    def __str__(self):
+        return self.name
+
+
+class AbstractBook(models.Model):
+    class Meta:
+        abstract = True
+
+    title = models.CharField(
+        max_length=255,
+        blank=False,
+        null=False,
+        unique=True,
+    )
+    libraries = models.ManyToManyField(Library)
+    data = JSONField(
+        default={},
+        blank=True,
+        null=True,
+        load_kwargs={'object_pairs_hook': collections.OrderedDict},
+        dump_kwargs={'indent': 4, 'cls': JSONEncoder, 'separators': (',', ':')},
+    )
+
+
+class Book(AbstractBook):
+    class Meta:
+        app_label = 'catalog'
+
+    def __str__(self):
+        return f"title: {self.title}, data={self.data}"
+
+
+class BookSpecialCopies(models.Model):
+    """
+    Intermediary that fan's out from a canonical book
+    to zero or more special RestrictedBooks copies of the book.
+    """
+    class Meta:
+        app_label = 'catalog'
+
+    book = models.OneToOneField(
+        Book,
+        related_name='special_copies',
+        on_delete=models.deletion.CASCADE,
+    )
+
+    def __str__(self):
+        return f"book={self.book}"
+
+
+class RestrictedBook(AbstractBook):
+    """
+    A copy of a book that's available only at a specific library.
+    """
+    class Meta:
+        app_label = 'catalog'
+
+    parent = models.ForeignKey(
+        BookSpecialCopies,
+        on_delete=models.deletion.CASCADE,
+    )
+    library = models.ForeignKey(
+        Library,
+        blank=False,
+        null=True,
+        related_name='special_copies',
+        on_delete=models.deletion.CASCADE,
+    )
+
+    def save(self, *args, **kwargs):
+        if not self.id:
+            super().save(*args, **kwargs)
+
+        self.title = self.parent.book.title
+        super().save(*args, **kwargs)
+
+    def __str__(self):
+        return f"title: {self.title}, specific_library: {self.library}, data={self.data}"
+
+"""
+from enterprise_catalog.apps.catalog.objects import *
+
+boston_pl = Library.objects.get(name='Boston Public Library')
+quincy_pl = Library.objects.get(name='Quincy Public Library')
+
+boston_copy = boston_pl.books.get(title='Moby Dick')
+boston_copy.library == boston_pl # False
+
+quincy_copy = quincy_pl.books.get(title='Moby Dick')
+quincy_copy.library == quincy_pl # True
+quincy_copy.restrictedbook.data_override
+"""