zulip/zerver/views/thumbnail.py

49 lines
1.7 KiB
Python

from typing import Optional, Union
from django.contrib.auth.models import AnonymousUser
from django.http import HttpRequest, HttpResponse, HttpResponseForbidden
from django.shortcuts import redirect
from django.utils.translation import gettext as _
from zerver.context_processors import get_valid_realm_from_request
from zerver.lib.attachments import validate_attachment_request
from zerver.lib.thumbnail import generate_thumbnail_url
from zerver.lib.typed_endpoint import typed_endpoint
from zerver.models import Realm, UserProfile
def validate_thumbnail_request(
realm: Realm,
maybe_user_profile: Union[UserProfile, AnonymousUser],
path: str,
) -> Optional[bool]:
# path here does not have a leading / as it is parsed from request hitting the
# thumbnail endpoint (defined in urls.py) that way.
if path.startswith("user_uploads/"):
path_id = path[len("user_uploads/") :]
return validate_attachment_request(maybe_user_profile, path_id, realm)
# This is an external link and we don't enforce restricted view policy here.
return True
@typed_endpoint
def backend_serve_thumbnail(
request: HttpRequest,
maybe_user_profile: Union[UserProfile, AnonymousUser],
*,
url: str,
size: str,
) -> HttpResponse:
if not maybe_user_profile.is_authenticated:
realm = get_valid_realm_from_request(request)
else:
assert isinstance(maybe_user_profile, UserProfile)
realm = maybe_user_profile.realm
if not validate_thumbnail_request(realm, maybe_user_profile, url):
return HttpResponseForbidden(_("<p>You are not authorized to view this file.</p>"))
thumbnail_url = generate_thumbnail_url(url)
return redirect(thumbnail_url)