add relay support - backend part

activities/migrations/0001_initial.py

@@ -16,7 +16,6 @@
 
 
 class Migration(migrations.Migration):
-
     initial = True
 
     dependencies = [
@@ -264,6 +263,7 @@ class Migration(migrations.Migration):
                             ("identity_edited", "Identity Edited"),
                             ("identity_deleted", "Identity Deleted"),
                             ("identity_created", "Identity Created"),
+                            ("identity_moved", "Identity Moved"),
                         ],
                         max_length=100,
                     ),

activities/models/fan_out.py

@@ -82,7 +82,7 @@ def handle_new(cls, instance: "FanOut"):
                             instance.identity.shared_inbox_uri
                             or instance.identity.inbox_uri
                         ),
-                        body=canonicalise(post.to_create_ap()),
+                        body=canonicalise(post.to_create_ap(), outbound_compat=True),
                     )
                 except httpx.RequestError:
                     return
@@ -98,7 +98,7 @@ def handle_new(cls, instance: "FanOut"):
                             instance.identity.shared_inbox_uri
                             or instance.identity.inbox_uri
                         ),
-                        body=canonicalise(post.to_update_ap()),
+                        body=canonicalise(post.to_update_ap(), outbound_compat=True),
                     )
                 except httpx.RequestError:
                     return
@@ -124,7 +124,7 @@ def handle_new(cls, instance: "FanOut"):
                             instance.identity.shared_inbox_uri
                             or instance.identity.inbox_uri
                         ),
-                        body=canonicalise(post.to_delete_ap()),
+                        body=canonicalise(post.to_delete_ap(), outbound_compat=True),
                     )
                 except httpx.RequestError:
                     return

activities/models/post.py

@@ -42,6 +42,7 @@
 from users.models.hashtag_follow import HashtagFollow
 from users.models.identity import Identity, IdentityStates
 from users.models.inbox_message import InboxMessage
+from users.models.relay_actor import RelayActor
 from users.models.system_actor import SystemActor
 
 
@@ -779,6 +780,12 @@ def get_targets(self) -> Iterable[Identity]:
                 targets.remove(block.target)
             except KeyError:
                 pass
+        # send local-created public posts to relays
+        if self.local and self.visibility in [
+            Post.Visibilities.public,
+            Post.Visibilities.unlisted,
+        ]:
+            targets.update(set(RelayActor.get_relays()))
         # Now dedupe the targets based on shared inboxes (we only keep one per
         # shared inbox)
         deduped_targets = set()

activities/models/post_interaction.py

@@ -10,6 +10,7 @@
 from core.snowflake import Snowflake
 from stator.models import State, StateField, StateGraph, StatorModel
 from users.models.identity import Identity
+from users.models.relay_actor import RelayActor
 
 
 class PostInteractionStates(StateGraph):
@@ -298,6 +299,11 @@ def to_ap(self) -> dict:
                 "object": self.post.object_uri,
                 "to": "as:Public",
             }
+            if self.identity.is_local_relay:
+                # if boost to relay, set "to" to remote relays instead of Public
+                value["to"] = list(
+                    RelayActor.get_relays().values_list("actor_uri", flat=True)
+                )
         elif self.type == self.Types.like:
             value = {
                 "type": "Like",
@@ -315,7 +321,7 @@ def to_ap(self) -> dict:
                 "inReplyTo": self.post.object_uri,
                 "attributedTo": self.identity.actor_uri,
             }
-        elif self.type == self.Types.pin:
+        else:
             raise ValueError("Cannot turn into AP")
         return value
 

activities/views/posts.py

@@ -67,6 +67,8 @@ def serve_object(self):
         if not self.post_obj.local:
             return redirect(self.post_obj.object_uri)
         return JsonResponse(
-            canonicalise(self.post_obj.to_ap(), include_security=True),
+            canonicalise(
+                self.post_obj.to_ap(), include_security=True, outbound_compat=True
+            ),
             content_type="application/activity+json",
         )

core/ld.py

@@ -87,7 +87,7 @@
                 "attachment": {"@id": "as:attachment", "@type": "@id"},
                 "bcc": {"@id": "as:bcc", "@type": "@id"},
                 "bto": {"@id": "as:bto", "@type": "@id"},
-                "cc": {"@id": "as:cc", "@type": "@id"},
+                "cc": {"@id": "as:cc", "@type": "@id", "@container": "@set"},
                 "context": {"@id": "as:context", "@type": "@id"},
                 "current": {"@id": "as:current", "@type": "@id"},
                 "first": {"@id": "as:first", "@type": "@id"},
@@ -119,7 +119,7 @@
                 "partOf": {"@id": "as:partOf", "@type": "@id"},
                 "tag": {"@id": "as:tag", "@type": "@id"},
                 "target": {"@id": "as:target", "@type": "@id"},
-                "to": {"@id": "as:to", "@type": "@id"},
+                "to": {"@id": "as:to", "@type": "@id", "@container": "@set"},
                 "url": {"@id": "as:url", "@type": "@id"},
                 "altitude": {"@id": "as:altitude", "@type": "xsd:float"},
                 "content": "as:content",
@@ -594,7 +594,9 @@ def builtin_document_loader(url: str, options={}):
             )
 
 
-def canonicalise(json_data: dict, include_security: bool = False) -> dict:
+def canonicalise(
+    json_data: dict, include_security: bool = False, outbound_compat: bool = False
+) -> dict:
     """
     Given an ActivityPub JSON-LD document, round-trips it through the LD
     systems to end up in a canonicalised, compacted format.
@@ -632,8 +634,18 @@ def canonicalise(json_data: dict, include_security: bool = False) -> dict:
         context.append("https://w3id.org/security/v1")
 
     json_data["@context"] = context
-
-    return jsonld.compact(jsonld.expand(json_data), context)
+    j = jsonld.compact(jsonld.expand(json_data), context)
+    if outbound_compat:
+        # patch outbound json to make it compatible with various implementations
+        for k in ["to", "cc"]:
+            if j.get(k):
+                j[k] = [
+                    x
+                    if x != "as:Public"
+                    else "https://www.w3.org/ns/activitystreams#Public"
+                    for x in j[k]
+                ]
+    return j
 
 
 def get_list(container, key) -> list:

core/models/config.py

@@ -230,7 +230,7 @@ class SystemOptions(pydantic.BaseModel):
         cache_timeout_page_post: int = 60 * 2
         cache_timeout_identity_feed: int = 60 * 5
 
-        restricted_usernames: str = "admin\nadmins\nadministrator\nadministrators\nsystem\nroot\nannounce\nannouncement\nannouncements"
+        restricted_usernames: str = "__system__\n__relay__\nadmin\nadmins\nadministrator\nadministrators\nsystem\nroot\nannounce\nannouncement\nannouncements"
 
         custom_head: str | None
 

takahe/urls.py

@@ -342,6 +342,7 @@
     path("actor/inbox/", activitypub.Inbox.as_view()),
     path("actor/outbox/", activitypub.EmptyOutbox.as_view()),
     path("inbox/", activitypub.Inbox.as_view(), name="shared_inbox"),
+    path("relay", activitypub.RelayActorView.as_view()),
     # API/Oauth
     path("api/", include("api.urls")),
     path("oauth/authorize", oauth.AuthorizationView.as_view()),

users/apps.py

@@ -12,9 +12,10 @@ def data_init(self, **kwargs):
         boot (or post upgrade).
         """
         # Generate the server actor keypair if needed
-        from users.models import SystemActor
+        from users.models import RelayActor, SystemActor
 
         SystemActor.generate_keys_if_needed()
+        RelayActor.initialize_if_needed()
 
     def ready(self) -> None:
         post_migrate.connect(self.data_init, sender=self)

users/models/__init__.py

@@ -8,6 +8,7 @@
 from .inbox_message import InboxMessage, InboxMessageStates  # noqa
 from .invite import Invite  # noqa
 from .password_reset import PasswordReset  # noqa
+from .relay_actor import RelayActor  # noqa
 from .report import Report  # noqa
 from .system_actor import SystemActor  # noqa
 from .user import User  # noqa

users/models/follow.py

@@ -74,7 +74,7 @@ def handle_unrequested(cls, instance: "Follow"):
                 instance.source.signed_request(
                     method="post",
                     uri=instance.target.inbox_uri,
-                    body=canonicalise(instance.to_ap()),
+                    body=canonicalise(instance.to_ap(), outbound_compat=True),
                 )
             except httpx.RequestError:
                 return
@@ -242,7 +242,11 @@ def create_local(cls, source, target, boosts=True):
                     uri="",
                     state=FollowStates.unrequested,
                 )
-                follow.uri = source.actor_uri + f"follow/{follow.pk}/"
+                follow.uri = (
+                    source.actor_uri
+                    + ("/" if source.actor_uri[-1] != "/" else "")
+                    + f"follow/{follow.pk}/"
+                )
                 follow.save()
         return follow
 

users/models/identity.py

@@ -32,6 +32,7 @@
 )
 from stator.models import State, StateField, StateGraph, StatorModel
 from users.models.domain import Domain
+from users.models.relay_actor import RelayActor
 from users.models.system_actor import SystemActor
 
 
@@ -337,6 +338,10 @@ def safe_metadata(self):
             for data in self.metadata
         ]
 
+    @property
+    def is_local_relay(self):
+        return self.local and self.actor_uri == RelayActor.actor_uri
+
     def ensure_uris(self):
         """
         Ensures that local identities have all the URIs populated on their fields

users/models/inbox_message.py

@@ -3,6 +3,7 @@
 
 from core.exceptions import ActivityPubError
 from stator.models import State, StateField, StateGraph, StatorModel
+from users.models.relay_actor import RelayActor
 
 
 class InboxMessageStates(StateGraph):
@@ -141,6 +142,10 @@ def handle_received(cls, instance: "InboxMessage"):
                             IdentityService.handle_internal_add_follow(
                                 instance.message["object"]
                             )
+                        case "unfollowrelay":
+                            RelayActor.handle_internal_unfollow(
+                                instance.message["object"]
+                            )
                         case unknown:
                             return cls.errored
                 case unknown: