create() produces instances of subtypes of Thing as appropriate.

django_kepi/create.py

@@ -1,6 +1,5 @@
-import django_kepi.models.thing as thing
-import django_kepi.models.audience as audience
-import django_kepi.models.actor as actor
+from django_kepi.models import *
+import django_kepi.types as types
 import logging
 import json
 
@@ -62,6 +61,30 @@ def create(
             }
     other_fields = value.copy()
 
+    try:
+        type_spec = types.ACTIVITYPUB_TYPES[value['type']]
+    except KeyError:
+        logger.info('Unknown thing type: %s; dropping message',
+                value['type'])
+        return None
+
+    if 'class' not in type_spec:
+        logger.info('Type %s can\'t be instantiated',
+                value['type'])
+        return None
+
+    try:
+        cls = globals()[type_spec['class']]
+    except KeyError:
+        # shouldn't happen!
+        logger.warn("The class '%s' wasn't imported into create.py",
+                type_spec['class'])
+        return None
+
+    logger.debug('Class for %s is %s', value['type'], cls)
+
+    # XXX get the record from "types", and see what fields we need
+
     try:
         need_actor, need_object, need_target = TYPES[value['type']]
     except KeyError:
@@ -131,9 +154,6 @@ def create(
         if f in other_fields:
             del other_fields[f]
 
-    # XXX decide "cls" here
-    cls = thing.Thing
-
     result = cls(**record_fields)
     result.save()
     logger.debug('Created %s (%s): ----',

django_kepi/migrations/0001_initial.py

@@ -1,4 +1,4 @@
-# Generated by Django 2.2.1 on 2019-05-24 18:32
+# Generated by Django 2.2.1 on 2019-06-29 10:26
 
 from django.db import migrations, models
 import django.db.models.deletion
@@ -10,6 +10,7 @@ class Migration(migrations.Migration):
     initial = True
 
     dependencies = [
+        ('contenttypes', '0002_remove_content_type_name'),
     ]
 
     operations = [
@@ -48,11 +49,61 @@ class Migration(migrations.Migration):
             name='Thing',
             fields=[
                 ('number', models.CharField(default='', max_length=8, primary_key=True, serialize=False, unique=True)),
-                ('f_type', models.CharField(choices=[('Reject', 'Reject'), ('Add', 'Add'), ('Follow', 'Follow'), ('Like', 'Like'), ('Undo', 'Undo'), ('Update', 'Update'), ('Accept', 'Accept'), ('Create', 'Create'), ('Remove', 'Remove'), ('Delete', 'Delete')], max_length=255)),
+                ('f_type', models.CharField(choices=[('Accept', 'Accept'), ('Add', 'Add'), ('Create', 'Create'), ('Delete', 'Delete'), ('Follow', 'Follow'), ('Like', 'Like'), ('Reject', 'Reject'), ('Remove', 'Remove'), ('Undo', 'Undo'), ('Update', 'Update')], max_length=255)),
                 ('remote_url', models.URLField(default=None, max_length=255, null=True, unique=True)),
                 ('f_actor', models.URLField(blank=True, max_length=255)),
                 ('f_name', models.CharField(blank=True, max_length=255)),
                 ('active', models.BooleanField(default=True)),
+                ('polymorphic_ctype', models.ForeignKey(editable=False, null=True, on_delete=django.db.models.deletion.CASCADE, related_name='polymorphic_django_kepi.thing_set+', to='contenttypes.ContentType')),
+            ],
+            options={
+                'abstract': False,
+                'base_manager_name': 'objects',
+            },
+        ),
+        migrations.CreateModel(
+            name='Activity',
+            fields=[
+                ('thing_ptr', models.OneToOneField(auto_created=True, on_delete=django.db.models.deletion.CASCADE, parent_link=True, primary_key=True, serialize=False, to='django_kepi.Thing')),
+            ],
+            options={
+                'abstract': False,
+                'base_manager_name': 'objects',
+            },
+            bases=('django_kepi.thing',),
+        ),
+        migrations.CreateModel(
+            name='Actor',
+            fields=[
+                ('thing_ptr', models.OneToOneField(auto_created=True, on_delete=django.db.models.deletion.CASCADE, parent_link=True, primary_key=True, serialize=False, to='django_kepi.Thing')),
+                ('privateKey', models.TextField()),
+                ('publicKey', models.TextField()),
+                ('auto_follow', models.BooleanField(default=True)),
+            ],
+            options={
+                'abstract': False,
+                'base_manager_name': 'objects',
+            },
+            bases=('django_kepi.thing',),
+        ),
+        migrations.CreateModel(
+            name='Item',
+            fields=[
+                ('thing_ptr', models.OneToOneField(auto_created=True, on_delete=django.db.models.deletion.CASCADE, parent_link=True, primary_key=True, serialize=False, to='django_kepi.Thing')),
+            ],
+            options={
+                'abstract': False,
+                'base_manager_name': 'objects',
+            },
+            bases=('django_kepi.thing',),
+        ),
+        migrations.CreateModel(
+            name='Audience',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('field', models.PositiveSmallIntegerField(choices=[(1, 'audience'), (2, 'to'), (4, 'cc'), (114, 'bto'), (116, 'bcc')])),
+                ('recipient', models.CharField(max_length=255)),
+                ('parent', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='django_kepi.Thing')),
             ],
         ),
         migrations.CreateModel(

django_kepi/models/__init__.py

@@ -0,0 +1,6 @@
+from .thing import Thing, ThingField
+from .activity import Activity
+from .actor import Actor
+from .audience import Audience
+from .following import Following
+from .item import Item

django_kepi/models/activity.py

@@ -0,0 +1,9 @@
+from . import thing
+import logging
+
+logger = logging.getLogger(name='django_kepi')
+
+######################
+
+class Activity(thing.Thing):
+    pass

django_kepi/models/actor.py

@@ -1,5 +1,5 @@
 from django.db import models
-import django_kepi.models.thing as thing
+from . import thing
 import django_kepi.crypto
 import logging
 

django_kepi/models/item.py

@@ -0,0 +1,11 @@
+from django.db import models
+from . import thing
+import logging
+
+logger = logging.getLogger(name='django_kepi')
+
+######################
+
+class Item(thing.Thing):
+    pass
+

tests/test_polymorph.py

@@ -0,0 +1,33 @@
+from django.test import TestCase
+from django_kepi.create import create
+from django_kepi.models import *
+import logging
+
+logger = logging.getLogger(name='tests')
+
+class TestPolymorph(TestCase):
+
+    def test_invalid_type(self):
+        t = create(
+                f_type = 'Wombat',
+                )
+        self.assertIsNone(t)
+
+    def test_note(self):
+        t = create(
+                f_type = 'Note',
+                )
+        self.assertIsInstance(t, Item)
+
+    def test_person(self):
+        t = create(
+                f_type = 'Person',
+                )
+        self.assertIsInstance(t, Actor)
+
+    def test_abstract(self):
+        t = create(
+                f_type = 'Object',
+                )
+        self.assertIsNone(t)
+