from django.db import models class TimelineEvent(models.Model): """ Something that has happened to an identity that we want them to see on one or more timelines, like posts, likes and follows. """ class Types(models.TextChoices): post = "post" boost = "boost" # A boost from someone (post substitude) mentioned = "mentioned" liked = "liked" # Someone liking one of our posts followed = "followed" boosted = "boosted" # Someone boosting one of our posts # The user this event is for identity = models.ForeignKey( "users.Identity", on_delete=models.CASCADE, related_name="timeline_events", ) # What type of event it is type = models.CharField(max_length=100, choices=Types.choices) # The subject of the event (which is used depends on the type) subject_post = models.ForeignKey( "activities.Post", on_delete=models.CASCADE, blank=True, null=True, related_name="timeline_events", ) subject_post_interaction = models.ForeignKey( "activities.PostInteraction", on_delete=models.CASCADE, blank=True, null=True, related_name="timeline_events", ) subject_identity = models.ForeignKey( "users.Identity", on_delete=models.CASCADE, blank=True, null=True, related_name="timeline_events_about_us", ) created = models.DateTimeField(auto_now_add=True) class Meta: index_together = [ # This relies on a DB that can use left subsets of indexes ("identity", "type", "subject_post", "subject_identity"), ("identity", "type", "subject_identity"), ] ### Alternate constructors ### @classmethod def add_follow(cls, identity, source_identity): """ Adds a follow to the timeline if it's not there already """ return cls.objects.get_or_create( identity=identity, type=cls.Types.follow, subject_identity=source_identity, )[0] @classmethod def add_post(cls, identity, post): """ Adds a post to the timeline if it's not there already """ return cls.objects.get_or_create( identity=identity, type=cls.Types.post, subject_post=post, )[0] @classmethod def add_post_interaction(cls, identity, interaction): """ Adds a boost/like to the timeline if it's not there already. For boosts, may make two objects - one "boost" and one "boosted". It'll return the "boost" in that case. """ if interaction.type == interaction.Types.like: return cls.objects.get_or_create( identity=identity, type=cls.Types.liked, subject_post_id=interaction.post_id, subject_identity_id=interaction.identity_id, subject_post_interaction=interaction, )[0] elif interaction.type == interaction.Types.boost: # If the boost is on one of our posts, then that's a boosted too if interaction.post.author_id == identity.id: return cls.objects.get_or_create( identity=identity, type=cls.Types.boosted, subject_post_id=interaction.post_id, subject_identity_id=interaction.identity_id, subject_post_interaction=interaction, )[0] return cls.objects.get_or_create( identity=identity, type=cls.Types.boost, subject_post_id=interaction.post_id, subject_identity_id=interaction.identity_id, subject_post_interaction=interaction, )[0] @classmethod def delete_post_interaction(cls, identity, interaction): if interaction.type == interaction.Types.like: cls.objects.filter( identity=identity, type=cls.Types.liked, subject_post_id=interaction.post_id, subject_identity_id=interaction.identity_id, ).delete() elif interaction.type == interaction.Types.boost: cls.objects.filter( identity=identity, type__in=[cls.Types.boosted, cls.Types.boost], subject_post_id=interaction.post_id, subject_identity_id=interaction.identity_id, ).delete()