zulip/zerver/lib/camo.py

25 lines
940 B
Python

from django.conf import settings
import codecs
import hashlib
import hmac
def generate_camo_url(url: str) -> str:
encoded_url = url.encode("utf-8")
encoded_camo_key = settings.CAMO_KEY.encode("utf-8")
digest = hmac.new(encoded_camo_key, encoded_url, hashlib.sha1).hexdigest()
hex_encoded_url = codecs.encode(encoded_url, "hex") # type: ignore # https://github.com/python/typeshed/issues/300
return "%s/%s" % (digest, hex_encoded_url.decode("utf-8"))
# Encodes the provided URL using the same algorithm used by the camo
# caching https image proxy
def get_camo_url(url: str) -> str:
# Only encode the url if Camo is enabled
if settings.CAMO_URI == '':
return url
return "%s%s" % (settings.CAMO_URI, generate_camo_url(url))
def is_camo_url_valid(digest: str, url: str) -> bool:
camo_url = generate_camo_url(url)
camo_url_digest = camo_url.split('/')[0]
return camo_url_digest == digest