Fetch actors with posts when needed

Fixes #190, #205

activities/models/post.py

@@ -23,6 +23,7 @@ from activities.models.post_types import (
 from activities.templatetags.emoji_tags import imageify_emojis
 from core.html import sanitize_post, strip_html
 from core.ld import canonicalise, format_ld_date, get_list, parse_ld_date
+from stator.exceptions import TryAgainLater
 from stator.models import State, StateField, StateGraph, StatorModel
 from users.models.identity import Identity, IdentityStates
 from users.models.system_actor import SystemActor
@@ -686,7 +687,7 @@ class Post(StatorModel):
     ### ActivityPub (inbound) ###
 
     @classmethod
-    def by_ap(cls, data, create=False, update=False) -> "Post":
+    def by_ap(cls, data, create=False, update=False, fetch_author=False) -> "Post":
         """
         Retrieves a Post instance by its ActivityPub JSON object.
 
@@ -704,8 +705,16 @@ class Post(StatorModel):
             if create:
                 # Resolve the author
                 author = Identity.by_actor_uri(data["attributedTo"], create=create)
+                # If the author is not fetched yet, try again later
+                if author.domain is None:
+                    if fetch_author:
+                        async_to_sync(author.fetch_actor)()
+                        if author.domain is None:
+                            raise TryAgainLater()
+                    else:
+                        raise TryAgainLater()
                 # If the post is from a blocked domain, stop and drop
-                if author.domain and author.domain.blocked:
+                if author.domain.blocked:
                     raise cls.DoesNotExist("Post is from a blocked domain")
                 post = cls.objects.create(
                     object_uri=data["id"],
@@ -800,6 +809,7 @@ class Post(StatorModel):
                     canonicalise(response.json(), include_security=True),
                     create=True,
                     update=True,
+                    fetch_author=True,
                 )
                 # We may need to fetch the author too
                 if post.author.state == IdentityStates.outdated:

activities/services/__init__.py

@@ -1 +1,2 @@
 from .post import PostService  # noqa
+from .search import SearchService  # noqa

activities/services/search.py

@@ -7,7 +7,7 @@ from users.models import Domain, Identity, IdentityStates
 from users.models.system_actor import SystemActor
 
 
-class Searcher:
+class SearchService:
     """
     Captures the logic needed to search - reused in the UI and API
     """

activities/views/search.py

@@ -1,7 +1,7 @@
 from django import forms
 from django.views.generic import FormView
 
-from activities.search import Searcher
+from activities.services import SearchService
 
 
 class Search(FormView):
@@ -15,7 +15,7 @@ class Search(FormView):
         )
 
     def form_valid(self, form):
-        searcher = Searcher(form.cleaned_data["query"], self.request.identity)
+        searcher = SearchService(form.cleaned_data["query"], self.request.identity)
         # Render results
         context = self.get_context_data(form=form)
         context["results"] = searcher.search_all()

api/views/search.py

@@ -3,7 +3,7 @@ from typing import Literal
 from ninja import Field
 
 from activities.models import PostInteraction
-from activities.search import Searcher
+from activities.services.search import SearchService
 from api import schemas
 from api.decorators import identity_required
 from api.views.base import api_router
@@ -32,7 +32,7 @@ def search(
     if max_id or since_id or min_id or offset:
         return result
     # Run search
-    searcher = Searcher(q, request.identity)
+    searcher = SearchService(q, request.identity)
     search_result = searcher.search_all()
     if type is None or type == "accounts":
         result["accounts"] = [i.to_mastodon_json() for i in search_result["identities"]]

stator/exceptions.py

@@ -0,0 +1,5 @@
+class TryAgainLater(BaseException):
+    """
+    Special exception that Stator will catch without error,
+    leaving a state to have another attempt soon.
+    """

stator/models.py

@@ -8,6 +8,7 @@ from django.utils import timezone
 from django.utils.functional import classproperty
 
 from core import exceptions
+from stator.exceptions import TryAgainLater
 from stator.graph import State, StateGraph
 
 
@@ -169,6 +170,8 @@ class StatorModel(models.Model):
             return None
         try:
             next_state = await current_state.handler(self)  # type: ignore
+        except TryAgainLater:
+            pass
         except BaseException as e:
             await exceptions.acapture_exception(e)
             traceback.print_exc()