Identity fanout (#196)

activities/migrations/0001_initial.py

@@ -262,6 +262,8 @@ class Migration(migrations.Migration):
                             ("post_deleted", "Post Deleted"),
                             ("interaction", "Interaction"),
                             ("undo_interaction", "Undo Interaction"),
+                            ("identity_edited", "Identity Edited"),
+                            ("identity_deleted", "Identity Deleted"),
                         ],
                         max_length=100,
                     ),

activities/migrations/0006_fanout_subject_identity_alter_fanout_type.py

@@ -0,0 +1,26 @@
+# Generated by Django 4.1.4 on 2022-12-18 00:20
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("users", "0005_report"),
+        ("activities", "0005_post_type_timeline_urls"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="fanout",
+            name="subject_identity",
+            field=models.ForeignKey(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.CASCADE,
+                related_name="subject_fan_outs",
+                to="users.identity",
+            ),
+        ),
+    ]

activities/models/fan_out.py

@@ -159,6 +159,36 @@ class FanOutStates(StateGraph):
                 except httpx.RequestError:
                     return
 
+            # Handle sending identity edited to remote
+            case (FanOut.Types.identity_edited, False):
+                identity = await fan_out.subject_identity.afetch_full()
+                try:
+                    await identity.signed_request(
+                        method="post",
+                        uri=fan_out.identity.inbox_uri,
+                        body=canonicalise(fan_out.subject_identity.to_update_ap()),
+                    )
+                except httpx.RequestError:
+                    return
+
+            # Handle sending identity deleted to remote
+            case (FanOut.Types.identity_deleted, False):
+                identity = await fan_out.subject_identity.afetch_full()
+                try:
+                    await identity.signed_request(
+                        method="post",
+                        uri=fan_out.identity.inbox_uri,
+                        body=canonicalise(fan_out.subject_identity.to_delete_ap()),
+                    )
+                except httpx.RequestError:
+                    return
+
+            # Sending identity edited/deleted to local is a no-op
+            case (FanOut.Types.identity_edited, True):
+                pass
+            case (FanOut.Types.identity_deleted, True):
+                pass
+
             case _:
                 raise ValueError(
                     f"Cannot fan out with type {fan_out.type} local={fan_out.identity.local}"
@@ -178,6 +208,8 @@ class FanOut(StatorModel):
         post_deleted = "post_deleted"
         interaction = "interaction"
         undo_interaction = "undo_interaction"
+        identity_edited = "identity_edited"
+        identity_deleted = "identity_deleted"
 
     state = StateField(FanOutStates)
 
@@ -206,6 +238,13 @@ class FanOut(StatorModel):
         null=True,
         related_name="fan_outs",
     )
+    subject_identity = models.ForeignKey(
+        "users.Identity",
+        on_delete=models.CASCADE,
+        blank=True,
+        null=True,
+        related_name="subject_fan_outs",
+    )
 
     created = models.DateTimeField(auto_now_add=True)
     updated = models.DateTimeField(auto_now=True)
@@ -221,6 +260,8 @@ class FanOut(StatorModel):
                 "identity",
                 "subject_post",
                 "subject_post_interaction",
+                "subject_identity",
+                "subject_identity__domain",
             )
             .prefetch_related(
                 "subject_post__emojis",

users/migrations/0001_initial.py

@@ -231,7 +231,13 @@ class Migration(migrations.Migration):
                 (
                     "state",
                     stator.models.StateField(
-                        choices=[("outdated", "outdated"), ("updated", "updated")],
+                        choices=[
+                            ("outdated", "outdated"),
+                            ("updated", "updated"),
+                            ("edited", "edited"),
+                            ("deleted", "deleted"),
+                            ("deleted_fanned_out", "deleted_fanned_out"),
+                        ],
                         default="outdated",
                         graph=users.models.identity.IdentityStates,
                         max_length=100,

users/models/identity.py

@@ -30,19 +30,76 @@ from users.models.system_actor import SystemActor
 
 class IdentityStates(StateGraph):
     """
-    There are only two states in a cycle.
     Identities sit in "updated" for up to system.identity_max_age, and then
     go back to "outdated" for refetching.
+
+    When a local identity is "edited" or "deleted", it will fanout the change to
+    all followers and transition to "updated"
     """
 
     outdated = State(try_interval=3600, force_initial=True)
     updated = State(try_interval=86400 * 7, attempt_immediately=False)
 
+    edited = State(try_interval=300, attempt_immediately=True)
+    deleted = State(try_interval=300, attempt_immediately=True)
+    deleted_fanned_out = State(externally_progressed=True)
+
+    deleted.transitions_to(deleted_fanned_out)
+
+    edited.transitions_to(updated)
+    updated.transitions_to(edited)
+    edited.transitions_to(deleted)
+
     outdated.transitions_to(updated)
     updated.transitions_to(outdated)
 
+    @classmethod
+    async def targets_fan_out(cls, identity: "Identity", type_: str) -> None:
+        from activities.models import FanOut
+        from users.models import Follow
+
+        # Fan out to each target
+        shared_inboxes = set()
+        async for follower in Follow.objects.select_related("source", "target").filter(
+            target=identity
+        ):
+            # Dedupe shared_inbox_uri
+            shared_uri = follower.source.shared_inbox_uri
+            if shared_uri and shared_uri in shared_inboxes:
+                continue
+
+            await FanOut.objects.acreate(
+                identity=follower.source,
+                type=type_,
+                subject_identity=identity,
+            )
+            shared_inboxes.add(shared_uri)
+
+    @classmethod
+    async def handle_edited(cls, instance: "Identity"):
+        from activities.models import FanOut
+
+        if not instance.local:
+            return cls.updated
+
+        identity = await instance.afetch_full()
+        await cls.targets_fan_out(identity, FanOut.Types.identity_edited)
+        return cls.updated
+
+    @classmethod
+    async def handle_deleted(cls, instance: "Identity"):
+        from activities.models import FanOut
+
+        if not instance.local:
+            return cls.updated
+
+        identity = await instance.afetch_full()
+        await cls.targets_fan_out(identity, FanOut.Types.identity_deleted)
+        return cls.deleted_fanned_out
+
     @classmethod
     async def handle_outdated(cls, identity: "Identity"):
+
         # Local identities never need fetching
         if identity.local:
             return cls.updated
@@ -56,6 +113,22 @@ class IdentityStates(StateGraph):
             return cls.outdated
 
 
+class IdentityQuerySet(models.QuerySet):
+    def not_deleted(self):
+        query = self.exclude(
+            state__in=[IdentityStates.deleted, IdentityStates.deleted_fanned_out]
+        )
+        return query
+
+
+class IdentityManager(models.Manager):
+    def get_queryset(self):
+        return IdentityQuerySet(self.model, using=self._db)
+
+    def not_deleted(self):
+        return self.get_queryset().not_deleted()
+
+
 class Identity(StatorModel):
     """
     Represents both local and remote Fediverse identities (actors)
@@ -135,6 +208,8 @@ class Identity(StatorModel):
     fetched = models.DateTimeField(null=True, blank=True)
     deleted = models.DateTimeField(null=True, blank=True)
 
+    objects = IdentityManager()
+
     ### Model attributes ###
 
     class Meta:
@@ -313,6 +388,14 @@ class Identity(StatorModel):
     def limited(self) -> bool:
         return self.restriction == self.Restriction.limited
 
+    ### Async helpers ###
+
+    async def afetch_full(self):
+        """
+        Returns a version of the object with all relations pre-loaded
+        """
+        return await Identity.objects.select_related("domain").aget(pk=self.pk)
+
     ### ActivityPub (outbound) ###
 
     def to_ap(self):
@@ -363,6 +446,30 @@ class Identity(StatorModel):
             "type": "Mention",
         }
 
+    def to_update_ap(self):
+        """
+        Returns the AP JSON to update this object
+        """
+        object = self.to_ap()
+        return {
+            "type": "Update",
+            "id": self.actor_uri + "#update",
+            "actor": self.actor_uri,
+            "object": object,
+        }
+
+    def to_delete_ap(self):
+        """
+        Returns the AP JSON to delete this object
+        """
+        object = self.to_ap()
+        return {
+            "type": "Delete",
+            "id": self.actor_uri + "#delete",
+            "actor": self.actor_uri,
+            "object": object,
+        }
+
     ### ActivityPub (inbound) ###
 
     @classmethod

users/views/settings/profile.py

@@ -7,6 +7,7 @@ from django.views.generic import FormView
 from core.files import resize_image
 from core.models.config import Config
 from users.decorators import identity_required
+from users.models import IdentityStates
 
 
 @method_decorator(identity_required, name="dispatch")
@@ -76,6 +77,8 @@ class ProfilePage(FormView):
                 resize_image(image, size=(1500, 500)),
             )
         identity.save()
+        identity.transition_perform(IdentityStates.edited)
+
         # Save profile-specific identity Config
         Config.set_identity(
             identity, "visible_follows", form.cleaned_data["visible_follows"]