bridgy-fed/convert.py

118 wiersze
4.2 KiB
Python

"""Serves ``/convert/...`` URLs to convert data from one protocol to another.
URL pattern is ``/convert/SOURCE/DEST``, where ``SOURCE`` and ``DEST`` are the
``LABEL`` constants from the :class:`protocol.Protocol` subclasses.
"""
import logging
import re
from urllib.parse import quote, unquote
from flask import g, redirect, request
from granary import as1
from oauth_dropins.webutil import flask_util, util
from oauth_dropins.webutil.flask_util import error
from activitypub import ActivityPub
from common import CACHE_TIME, LOCAL_DOMAINS, subdomain_wrap, SUPERDOMAIN
from flask_app import app, cache
from models import Object, PROTOCOLS
from protocol import Protocol
from web import Web
logger = logging.getLogger(__name__)
@app.get(f'/convert/<dest>/<path:_>')
@flask_util.cached(cache, CACHE_TIME, headers=['Accept'])
def convert(dest, _, src=None):
"""Converts data from one protocol to another and serves it.
Fetches the source data if it's not already stored.
Args:
dest (str): protocol
src (str): protocol, only used when called by
:func:`convert_source_path_redirect`
"""
if src:
src_cls = PROTOCOLS.get(src)
if not src_cls:
error(f'No protocol found for {src}', status=404)
logger.info(f'Overriding any domain protocol with {src}')
else:
src_cls = Protocol.for_request(fed=Protocol)
if not src_cls:
error(f'Unknown protocol {request.host.removesuffix(SUPERDOMAIN)}', status=404)
dest_cls = PROTOCOLS.get(dest)
if not dest_cls:
error('Unknown protocol {dest}', status=404)
# don't use urllib.parse.urlencode(request.args) because that doesn't
# guarantee us the same query param string as in the original URL, and we
# want exactly the same thing since we're looking up the URL's Object by id
path_prefix = f'convert/{dest}/'
id = unquote(request.url.removeprefix(request.root_url).removeprefix(path_prefix))
# our redirects evidently collapse :// down to :/ , maybe to prevent URL
# parsing bugs? if that happened to this URL, expand it back to ://
id = re.sub(r'^(https?:/)([^/])', r'\1/\2', id)
logger.info(f'Converting from {src_cls.LABEL} to {dest}: {id}')
# load, and maybe fetch. if it's a post/update, redirect to inner object.
obj = src_cls.load(id)
if not obj:
error(f"Couldn't load {id}", status=404)
elif not obj.as1:
error(f'Stored object for {id} has no data', status=404)
type = as1.object_type(obj.as1)
if type in ('post', 'update', 'delete'):
obj_id = as1.get_object(obj.as1).get('id')
if obj_id:
obj_obj = src_cls.load(obj_id, remote=False)
if (obj_obj and obj_obj.as1
and not obj_obj.as1.keys() <= set(['id', 'url', 'objectType'])):
logger.info(f'{type} activity, redirecting to Object {obj_id}')
return redirect(f'/{path_prefix}{obj_id}', code=301)
# don't serve deletes or deleted objects
if obj.deleted or type == 'delete':
return '', 410
# convert and serve
return dest_cls.convert(obj), {'Content-Type': dest_cls.CONTENT_TYPE}
@app.get('/render')
def render_redirect():
"""Redirect from old /render?id=... endpoint to /convert/..."""
id = flask_util.get_required_param('id')
return redirect(subdomain_wrap(ActivityPub, f'/convert/web/{id}'), code=301)
@app.get(f'/convert/<src>/<dest>/<path:_>')
def convert_source_path_redirect(src, dest, _):
"""Old route that included source protocol in path instead of subdomain.
DEPRECATED! Only kept to support old webmention source URLs.
"""
if Protocol.for_request() not in (None, 'web'): # no per-protocol subdomains
error(f'Try again on fed.brid.gy', status=404)
# in prod, eg gunicorn, the path somehow gets URL-decoded before we see
# it, so we need to re-encode.
new_path = quote(request.full_path.rstrip('?').replace(f'/{src}/', '/'),
safe=':/%')
if request.host in LOCAL_DOMAINS:
request.url = request.url.replace(f'/{src}/', '/')
return convert(dest, None, src)
proto = PROTOCOLS.get(src)
if not proto:
error(f'No protocol found for {src}', status=404)
return redirect(subdomain_wrap(proto, new_path), code=301)