moviewyrm/bookwyrm/models/relationship.py
2022-03-26 10:34:02 -07:00

224 lines
7.6 KiB
Python

""" defines relationships between users """
from django.apps import apps
from django.core.cache import cache
from django.db import models, transaction, IntegrityError
from django.db.models import Q
from bookwyrm import activitypub
from .activitypub_mixin import ActivitypubMixin, ActivityMixin
from .activitypub_mixin import generate_activity
from .base_model import BookWyrmModel
from . import fields
class UserRelationship(BookWyrmModel):
"""many-to-many through table for followers"""
user_subject = fields.ForeignKey(
"User",
on_delete=models.PROTECT,
related_name="%(class)s_user_subject",
activitypub_field="actor",
)
user_object = fields.ForeignKey(
"User",
on_delete=models.PROTECT,
related_name="%(class)s_user_object",
activitypub_field="object",
)
@property
def privacy(self):
"""all relationships are handled directly with the participants"""
return "direct"
@property
def recipients(self):
"""the remote user needs to recieve direct broadcasts"""
return [u for u in [self.user_subject, self.user_object] if not u.local]
def save(self, *args, **kwargs):
"""clear the template cache"""
clear_cache(self.user_subject, self.user_object)
super().save(*args, **kwargs)
def delete(self, *args, **kwargs):
"""clear the template cache"""
clear_cache(self.user_subject, self.user_object)
super().delete(*args, **kwargs)
class Meta:
"""relationships should be unique"""
abstract = True
constraints = [
models.UniqueConstraint(
fields=["user_subject", "user_object"], name="%(class)s_unique"
),
models.CheckConstraint(
check=~models.Q(user_subject=models.F("user_object")),
name="%(class)s_no_self",
),
]
def get_remote_id(self):
"""use shelf identifier in remote_id"""
base_path = self.user_subject.remote_id
return f"{base_path}#follows/{self.id}"
class UserFollows(ActivityMixin, UserRelationship):
"""Following a user"""
status = "follows"
def to_activity(self): # pylint: disable=arguments-differ
"""overrides default to manually set serializer"""
return activitypub.Follow(**generate_activity(self))
def save(self, *args, **kwargs):
"""really really don't let a user follow someone who blocked them"""
# blocking in either direction is a no-go
if UserBlocks.objects.filter(
Q(
user_subject=self.user_subject,
user_object=self.user_object,
)
| Q(
user_subject=self.user_object,
user_object=self.user_subject,
)
).exists():
raise IntegrityError(
"Attempting to follow blocked user", self.user_subject, self.user_object
)
# don't broadcast this type of relationship -- accepts and requests
# are handled by the UserFollowRequest model
super().save(*args, broadcast=False, **kwargs)
@classmethod
def from_request(cls, follow_request):
"""converts a follow request into a follow relationship"""
obj, _ = cls.objects.get_or_create(
user_subject=follow_request.user_subject,
user_object=follow_request.user_object,
remote_id=follow_request.remote_id,
)
return obj
class UserFollowRequest(ActivitypubMixin, UserRelationship):
"""following a user requires manual or automatic confirmation"""
status = "follow_request"
activity_serializer = activitypub.Follow
def save(self, *args, broadcast=True, **kwargs): # pylint: disable=arguments-differ
"""make sure the follow or block relationship doesn't already exist"""
# if there's a request for a follow that already exists, accept it
# without changing the local database state
if UserFollows.objects.filter(
user_subject=self.user_subject,
user_object=self.user_object,
).exists():
self.accept(broadcast_only=True)
return
# blocking in either direction is a no-go
if UserBlocks.objects.filter(
Q(
user_subject=self.user_subject,
user_object=self.user_object,
)
| Q(
user_subject=self.user_object,
user_object=self.user_subject,
)
).exists():
raise IntegrityError(
"Attempting to follow blocked user", self.user_subject, self.user_object
)
super().save(*args, **kwargs)
if broadcast and self.user_subject.local and not self.user_object.local:
self.broadcast(self.to_activity(), self.user_subject)
if self.user_object.local:
manually_approves = self.user_object.manually_approves_followers
if not manually_approves:
self.accept()
model = apps.get_model("bookwyrm.Notification", require_ready=True)
notification_type = "FOLLOW_REQUEST" if manually_approves else "FOLLOW"
model.objects.create(
user=self.user_object,
related_user=self.user_subject,
notification_type=notification_type,
)
def get_accept_reject_id(self, status):
"""get id for sending an accept or reject of a local user"""
base_path = self.user_object.remote_id
status_id = self.id or 0
return f"{base_path}#{status}/{status_id}"
def accept(self, broadcast_only=False):
"""turn this request into the real deal"""
user = self.user_object
if not self.user_subject.local:
activity = activitypub.Accept(
id=self.get_accept_reject_id(status="accepts"),
actor=self.user_object.remote_id,
object=self.to_activity(),
).serialize()
self.broadcast(activity, user)
if broadcast_only:
return
with transaction.atomic():
UserFollows.from_request(self)
if self.id:
self.delete()
def reject(self):
"""generate a Reject for this follow request"""
if self.user_object.local:
activity = activitypub.Reject(
id=self.get_accept_reject_id(status="rejects"),
actor=self.user_object.remote_id,
object=self.to_activity(),
).serialize()
self.broadcast(activity, self.user_object)
self.delete()
class UserBlocks(ActivityMixin, UserRelationship):
"""prevent another user from following you and seeing your posts"""
status = "blocks"
activity_serializer = activitypub.Block
def save(self, *args, **kwargs):
"""remove follow or follow request rels after a block is created"""
super().save(*args, **kwargs)
UserFollows.objects.filter(
Q(user_subject=self.user_subject, user_object=self.user_object)
| Q(user_subject=self.user_object, user_object=self.user_subject)
).delete()
UserFollowRequest.objects.filter(
Q(user_subject=self.user_subject, user_object=self.user_object)
| Q(user_subject=self.user_object, user_object=self.user_subject)
).delete()
def clear_cache(user_subject, user_object):
"""clear relationship cache"""
cache.delete_many(
[
f"relationship-{user_subject.id}-{user_object.id}",
f"relationship-{user_object.id}-{user_subject.id}",
]
)