mirror of
https://github.com/bookwyrm-social/bookwyrm.git
synced 2024-06-10 09:19:27 +00:00
212 lines
7.3 KiB
Python
212 lines
7.3 KiB
Python
""" store recommended follows in redis """
|
|
import math
|
|
from django.dispatch import receiver
|
|
from django.db.models import signals, Count, Q
|
|
|
|
from bookwyrm import models
|
|
from bookwyrm.redis_store import RedisStore, r
|
|
from bookwyrm.tasks import app
|
|
|
|
|
|
class SuggestedUsers(RedisStore):
|
|
"""suggested users for a user"""
|
|
|
|
max_length = 30
|
|
|
|
def get_rank(self, obj):
|
|
"""get computed rank"""
|
|
return obj.mutuals + (1.0 - (1.0 / (obj.shared_books + 1)))
|
|
|
|
def store_id(self, user): # pylint: disable=no-self-use
|
|
"""the key used to store this user's recs"""
|
|
if isinstance(user, int):
|
|
return "{:d}-suggestions".format(user)
|
|
return "{:d}-suggestions".format(user.id)
|
|
|
|
def get_counts_from_rank(self, rank): # pylint: disable=no-self-use
|
|
"""calculate mutuals count and shared books count from rank"""
|
|
return {
|
|
"mutuals": math.floor(rank),
|
|
"shared_books": int(1 / (-1 * (rank % 1 - 1))) - 1,
|
|
}
|
|
|
|
def get_objects_for_store(self, store):
|
|
"""a list of potential follows for a user"""
|
|
user = models.User.objects.get(id=store.split("-")[0])
|
|
|
|
return get_annotated_users(
|
|
user,
|
|
~Q(id=user.id),
|
|
~Q(followers=user),
|
|
~Q(follower_requests=user),
|
|
bookwyrm_user=True,
|
|
)
|
|
|
|
def get_stores_for_object(self, obj):
|
|
return [self.store_id(u) for u in self.get_users_for_object(obj)]
|
|
|
|
def get_users_for_object(self, obj): # pylint: disable=no-self-use
|
|
"""given a user, who might want to follow them"""
|
|
return models.User.objects.filter(
|
|
local=True,
|
|
).exclude(
|
|
Q(id=obj.id) | Q(followers=obj) | Q(id__in=obj.blocks.all()) | Q(blocks=obj)
|
|
)
|
|
|
|
def rerank_obj(self, obj, update_only=True):
|
|
"""update all the instances of this user with new ranks"""
|
|
pipeline = r.pipeline()
|
|
for store_user in self.get_users_for_object(obj):
|
|
annotated_user = get_annotated_users(
|
|
store_user,
|
|
id=obj.id,
|
|
).first()
|
|
if not annotated_user:
|
|
continue
|
|
|
|
pipeline.zadd(
|
|
self.store_id(store_user),
|
|
self.get_value(annotated_user),
|
|
xx=update_only,
|
|
)
|
|
pipeline.execute()
|
|
|
|
def rerank_user_suggestions(self, user):
|
|
"""update the ranks of the follows suggested to a user"""
|
|
self.populate_store(self.store_id(user))
|
|
|
|
def remove_suggestion(self, user, suggested_user):
|
|
"""take a user out of someone's suggestions"""
|
|
self.bulk_remove_objects_from_store([suggested_user], self.store_id(user))
|
|
|
|
def get_suggestions(self, user):
|
|
"""get suggestions"""
|
|
values = self.get_store(self.store_id(user), withscores=True)
|
|
results = []
|
|
# annotate users with mutuals and shared book counts
|
|
for user_id, rank in values[:5]:
|
|
counts = self.get_counts_from_rank(rank)
|
|
user = models.User.objects.get(id=user_id)
|
|
user.mutuals = counts["mutuals"]
|
|
user.shared_books = counts["shared_books"]
|
|
results.append(user)
|
|
return results
|
|
|
|
|
|
def get_annotated_users(viewer, *args, **kwargs):
|
|
"""Users, annotated with things they have in common"""
|
|
return (
|
|
models.User.objects.filter(discoverable=True, is_active=True, *args, **kwargs)
|
|
.exclude(Q(id__in=viewer.blocks.all()) | Q(blocks=viewer))
|
|
.annotate(
|
|
mutuals=Count(
|
|
"followers",
|
|
filter=Q(
|
|
~Q(id=viewer.id),
|
|
~Q(id__in=viewer.following.all()),
|
|
followers__in=viewer.following.all(),
|
|
),
|
|
distinct=True,
|
|
),
|
|
shared_books=Count(
|
|
"shelfbook",
|
|
filter=Q(
|
|
~Q(id=viewer.id),
|
|
shelfbook__book__parent_work__in=[
|
|
s.book.parent_work for s in viewer.shelfbook_set.all()
|
|
],
|
|
),
|
|
distinct=True,
|
|
),
|
|
)
|
|
)
|
|
|
|
|
|
suggested_users = SuggestedUsers()
|
|
|
|
|
|
@receiver(signals.post_save, sender=models.UserFollows)
|
|
# pylint: disable=unused-argument
|
|
def update_suggestions_on_follow(sender, instance, created, *args, **kwargs):
|
|
"""remove a follow from the recs and update the ranks"""
|
|
if not created or not instance.user_object.discoverable:
|
|
return
|
|
|
|
if instance.user_subject.local:
|
|
remove_suggestion_task.delay(instance.user_subject.id, instance.user_object.id)
|
|
rerank_user_task.delay(instance.user_object.id)
|
|
|
|
|
|
@receiver(signals.post_save, sender=models.UserBlocks)
|
|
# pylint: disable=unused-argument
|
|
def update_suggestions_on_block(sender, instance, *args, **kwargs):
|
|
"""remove blocked users from recs"""
|
|
if instance.user_subject.local:
|
|
remove_suggestion_task.delay(instance.user_subject.id, instance.user_object.id)
|
|
if instance.user_object.local:
|
|
remove_suggestion_task.delay(instance.user_object.id, instance.user_subject.id)
|
|
|
|
|
|
@receiver(signals.post_delete, sender=models.UserFollows)
|
|
# pylint: disable=unused-argument
|
|
def update_suggestions_on_unfollow(sender, instance, **kwargs):
|
|
"""update rankings, but don't re-suggest because it was probably intentional"""
|
|
if instance.user_object.discoverable:
|
|
rerank_user_task.delay(instance.user_object.id)
|
|
|
|
|
|
@receiver(signals.post_save, sender=models.ShelfBook)
|
|
@receiver(signals.post_delete, sender=models.ShelfBook)
|
|
# pylint: disable=unused-argument
|
|
def update_rank_on_shelving(sender, instance, *args, **kwargs):
|
|
"""when a user shelves or unshelves a book, re-compute their rank"""
|
|
# if it's a local user, re-calculate who is rec'ed to them
|
|
if instance.user.local:
|
|
rerank_suggestions_task.delay(instance.user.id)
|
|
|
|
# if the user is discoverable, update their rankings
|
|
if instance.user.discoverable:
|
|
rerank_user_task.delay(instance.user.id)
|
|
|
|
|
|
@receiver(signals.post_save, sender=models.User)
|
|
# pylint: disable=unused-argument, too-many-arguments
|
|
def add_new_user(sender, instance, created, **kwargs):
|
|
"""a new user, wow how cool"""
|
|
# a new user is found, create suggestions for them
|
|
if created and instance.local:
|
|
rerank_suggestions_task.delay(instance.id)
|
|
|
|
# this happens on every save, not just when discoverability changes, annoyingly
|
|
if instance.discoverable:
|
|
rerank_user_task.delay(instance.id, update_only=False)
|
|
elif not created:
|
|
remove_user_task.delay(instance.id)
|
|
|
|
|
|
@app.task
|
|
def rerank_suggestions_task(user_id):
|
|
"""do the hard work in celery"""
|
|
suggested_users.rerank_user_suggestions(user_id)
|
|
|
|
|
|
@app.task
|
|
def rerank_user_task(user_id, update_only=False):
|
|
"""do the hard work in celery"""
|
|
user = models.User.objects.get(id=user_id)
|
|
suggested_users.rerank_obj(user, update_only=update_only)
|
|
|
|
|
|
@app.task
|
|
def remove_user_task(user_id):
|
|
"""do the hard work in celery"""
|
|
user = models.User.objects.get(id=user_id)
|
|
suggested_users.remove_object_from_related_stores(user)
|
|
|
|
|
|
@app.task
|
|
def remove_suggestion_task(user_id, suggested_user_id):
|
|
"""remove a specific user from a specific user's suggestions"""
|
|
suggested_user = models.User.objects.get(id=suggested_user_id)
|
|
suggested_users.remove_suggestion(user_id, suggested_user)
|