from asgiref.sync import sync_to_async from django.db import models from activities.models.timeline_event import TimelineEvent from core.ld import canonicalise from stator.models import State, StateField, StateGraph, StatorModel class FanOutStates(StateGraph): new = State(try_interval=300) sent = State() new.transitions_to(sent) @classmethod async def handle_new(cls, instance: "FanOut"): """ Sends the fan-out to the right inbox. """ fan_out = await instance.afetch_full() # Handle Posts if fan_out.type == FanOut.Types.post: post = await fan_out.subject_post.afetch_full() if fan_out.identity.local: # Make a timeline event directly # TODO: Exclude replies to people we don't follow await sync_to_async(TimelineEvent.add_post)( identity=fan_out.identity, post=post, ) # We might have been mentioned if fan_out.identity in list(post.mentions.all()): TimelineEvent.add_mentioned( identity=fan_out.identity, post=post, ) else: # Sign it and send it await post.author.signed_request( method="post", uri=fan_out.identity.inbox_uri, body=canonicalise(post.to_create_ap()), ) # Handle deleting posts elif fan_out.type == FanOut.Types.post_deleted: post = await fan_out.subject_post.afetch_full() if fan_out.identity.local: # Remove all timeline events mentioning it await TimelineEvent.objects.filter( identity=fan_out.identity, subject_post=post, ).adelete() else: # Send it to the remote inbox await post.author.signed_request( method="post", uri=fan_out.identity.inbox_uri, body=canonicalise(post.to_delete_ap()), ) # Handle boosts/likes elif fan_out.type == FanOut.Types.interaction: interaction = await fan_out.subject_post_interaction.afetch_full() if fan_out.identity.local: # Make a timeline event directly await sync_to_async(TimelineEvent.add_post_interaction)( identity=fan_out.identity, interaction=interaction, ) else: # Send it to the remote inbox await interaction.identity.signed_request( method="post", uri=fan_out.identity.inbox_uri, body=canonicalise(interaction.to_ap()), ) # Handle undoing boosts/likes elif fan_out.type == FanOut.Types.undo_interaction: interaction = await fan_out.subject_post_interaction.afetch_full() if fan_out.identity.local: # Delete any local timeline events await sync_to_async(TimelineEvent.delete_post_interaction)( identity=fan_out.identity, interaction=interaction, ) else: # Send an undo to the remote inbox await interaction.identity.signed_request( method="post", uri=fan_out.identity.inbox_uri, body=canonicalise(interaction.to_undo_ap()), ) else: raise ValueError(f"Cannot fan out with type {fan_out.type}") return cls.sent class FanOut(StatorModel): """ An activity that needs to get to an inbox somewhere. """ class Types(models.TextChoices): post = "post" post_edited = "post_edited" post_deleted = "post_deleted" interaction = "interaction" undo_interaction = "undo_interaction" state = StateField(FanOutStates) # The user this event is targeted at identity = models.ForeignKey( "users.Identity", on_delete=models.CASCADE, related_name="fan_outs", ) # What type of activity it is type = models.CharField(max_length=100, choices=Types.choices) # Links to the appropriate objects subject_post = models.ForeignKey( "activities.Post", on_delete=models.CASCADE, blank=True, null=True, related_name="fan_outs", ) subject_post_interaction = models.ForeignKey( "activities.PostInteraction", on_delete=models.CASCADE, blank=True, null=True, related_name="fan_outs", ) created = models.DateTimeField(auto_now_add=True) updated = models.DateTimeField(auto_now=True) ### Async helpers ### async def afetch_full(self): """ Returns a version of the object with all relations pre-loaded """ return await FanOut.objects.select_related( "identity", "subject_post", "subject_post_interaction", ).aget(pk=self.pk)