Clean up Reddit's defective Atom feed. Runs locally or as CGI.

RedditAtom.py

#!/usr/bin/env python3
import cgi
#import cgitb
#cgitb.enable()

import json
import urllib.request
import urllib.parse
from html import unescape
from werkzeug.contrib.atom import AtomFeed
from datetime import datetime
from pytz import utc
import sys, os

form=cgi.FieldStorage()
if form.getvalue("url"):
	BASE_URL=form.getvalue("url")
elif len(sys.argv) >= 3:
	BASE_URL=sys.argv[2]
else:
	BASE_URL="http://reddit.com/r/{}/.json"

if form.getvalue("r"):
	SUBREDDIT=form.getvalue("r")
elif len(sys.argv) >= 2:
	SUBREDDIT=sys.argv[1]
else:
	SUBREDDIT="all"

RSS_URL=BASE_URL.format(SUBREDDIT)

headers={'User-Agent': "RedditAtom 0.4"}
if "REMOTE_ADDR" in os.environ:
	headers['X-Forwarded-For']=os.environ["REMOTE_ADDR"]
with urllib.request.urlopen(
 urllib.request.Request(url=RSS_URL, headers=headers)
) as response:
	response_json = json.loads(
	 response.read().decode()
	)

posts = [post['data'] for post in response_json['data']['children'] if post['kind'] == 't3']

atom = AtomFeed(title='/r/' + RSS_URL.rstrip('.json').split('/r/')[-1], feed_url=RSS_URL)

for post in posts:
	atom.add(
	 title        = unescape(post['title']),
	 content      = unescape(post['selftext_html']) if post['selftext_html'] else None,
	 content_type = "html",
	 url          = post['permalink'],
	 author       = post['author'],
	 id           = post['id'],
	 updated      = datetime.fromtimestamp(post['created_utc'], tz=utc),
	 links        = [{'href': post['url'], 'rel': "self" if post['url'].endswith(post['permalink']) else "enclosure"}]
	)

if "REMOTE_ADDR" in os.environ:
	sys.stdout.buffer.write('Content-type: application/atom+xml\n'.encode())
	
	sys.stdout.buffer.write('\n'.encode())

sys.stdout.buffer.write(atom.to_string().encode())