takahe/core/html.py

33 lines
941 B
Python

import bleach
from bleach.linkifier import LinkifyFilter
from django.utils.safestring import mark_safe
def allow_a(tag: str, name: str, value: str):
if name in ["href", "title", "class"]:
return True
elif name == "rel":
# Only allow rel attributes with a small subset of values
# (we're defending against, for example, rel=me)
rel_values = value.split()
if all(v in ["nofollow", "noopener", "noreferrer", "tag"] for v in rel_values):
return True
return False
def sanitize_post(post_html: str) -> str:
"""
Only allows a, br, p and span tags, and class attributes.
"""
cleaner = bleach.Cleaner(
tags=["br", "p"],
attributes={ # type:ignore
"a": allow_a,
"p": ["class"],
"span": ["class"],
},
filters=[LinkifyFilter],
strip=True,
)
return mark_safe(cleaner.clean(post_html))