moviewyrm/bookwyrm/views/helpers.py
2021-06-18 16:56:33 -07:00

179 lines
5.8 KiB
Python

""" helper functions used in various views """
import re
from requests import HTTPError
from django.core.exceptions import FieldError
from django.db.models import Max, Q
from django.http import Http404
from bookwyrm import activitypub, models
from bookwyrm.connectors import ConnectorException, get_data
from bookwyrm.status import create_generated_note
from bookwyrm.utils import regex
def get_user_from_username(viewer, username):
"""helper function to resolve a localname or a username to a user"""
if viewer.is_authenticated and viewer.localname == username:
# that's yourself, fool
return viewer
# raises 404 if the user isn't found
try:
return models.User.viewer_aware_objects(viewer).get(localname=username)
except models.User.DoesNotExist:
pass
# if the localname didn't match, try the username
try:
return models.User.viewer_aware_objects(viewer).get(username=username)
except models.User.DoesNotExist:
raise Http404()
def is_api_request(request):
"""check whether a request is asking for html or data"""
return "json" in request.headers.get("Accept", "") or request.path[-5:] == ".json"
def is_bookwyrm_request(request):
"""check if the request is coming from another bookwyrm instance"""
user_agent = request.headers.get("User-Agent")
if user_agent is None or re.search(regex.BOOKWYRM_USER_AGENT, user_agent) is None:
return False
return True
def privacy_filter(viewer, queryset, privacy_levels=None, following_only=False):
"""filter objects that have "user" and "privacy" fields"""
privacy_levels = privacy_levels or ["public", "unlisted", "followers", "direct"]
# if there'd a deleted field, exclude deleted items
try:
queryset = queryset.filter(deleted=False)
except FieldError:
pass
# exclude blocks from both directions
if not viewer.is_anonymous:
blocked = models.User.objects.filter(id__in=viewer.blocks.all()).all()
queryset = queryset.exclude(Q(user__in=blocked) | Q(user__blocks=viewer))
# you can't see followers only or direct messages if you're not logged in
if viewer.is_anonymous:
privacy_levels = [p for p in privacy_levels if not p in ["followers", "direct"]]
# filter to only privided privacy levels
queryset = queryset.filter(privacy__in=privacy_levels)
# only include statuses the user follows
if following_only:
queryset = queryset.exclude(
~Q( # remove everythign except
Q(user__in=viewer.following.all())
| Q(user=viewer) # user following
| Q(mention_users=viewer) # is self # mentions user
),
)
# exclude followers-only statuses the user doesn't follow
elif "followers" in privacy_levels:
queryset = queryset.exclude(
~Q( # user isn't following and it isn't their own status
Q(user__in=viewer.following.all()) | Q(user=viewer)
),
privacy="followers", # and the status is followers only
)
# exclude direct messages not intended for the user
if "direct" in privacy_levels:
try:
queryset = queryset.exclude(
~Q(Q(user=viewer) | Q(mention_users=viewer)), privacy="direct"
)
except FieldError:
queryset = queryset.exclude(~Q(user=viewer), privacy="direct")
return queryset
def handle_remote_webfinger(query):
"""webfingerin' other servers"""
user = None
# usernames could be @user@domain or user@domain
if not query:
return None
if query[0] == "@":
query = query[1:]
try:
domain = query.split("@")[1]
except IndexError:
return None
try:
user = models.User.objects.get(username__iexact=query)
except models.User.DoesNotExist:
url = "https://%s/.well-known/webfinger?resource=acct:%s" % (domain, query)
try:
data = get_data(url)
except (ConnectorException, HTTPError):
return None
for link in data.get("links"):
if link.get("rel") == "self":
try:
user = activitypub.resolve_remote_id(
link["href"], model=models.User
)
except (KeyError, activitypub.ActivitySerializerError):
return None
return user
def get_edition(book_id):
"""look up a book in the db and return an edition"""
book = models.Book.objects.select_subclasses().get(id=book_id)
if isinstance(book, models.Work):
book = book.default_edition
return book
def handle_reading_status(user, shelf, book, privacy):
"""post about a user reading a book"""
# tell the world about this cool thing that happened
try:
message = {
"to-read": "wants to read",
"reading": "started reading",
"read": "finished reading",
}[shelf.identifier]
except KeyError:
# it's a non-standard shelf, don't worry about it
return
status = create_generated_note(user, message, mention_books=[book], privacy=privacy)
status.save()
def is_blocked(viewer, user):
"""is this viewer blocked by the user?"""
if viewer.is_authenticated and viewer in user.blocks.all():
return True
return False
def get_discover_books():
"""list of books for the discover page"""
return list(
set(
models.Edition.objects.filter(
review__published_date__isnull=False,
review__deleted=False,
review__user__local=True,
review__privacy__in=["public", "unlisted"],
)
.exclude(cover__exact="")
.annotate(Max("review__published_date"))
.order_by("-review__published_date__max")[:6]
)
)