Convert authorized press release RSS to JSON in Python

from datetime import timezone
from email.utils import parsedate_to_datetime
import xml.etree.ElementTree as ET

DC = "{http://purl.org/dc/elements/1.1/}"

def parse_release_feed(xml_bytes):
    if len(xml_bytes) > 2_000_000 or b"<!DOCTYPE" in xml_bytes.upper():
        raise ValueError("unsupported XML payload")
    channel = ET.fromstring(xml_bytes).find("channel")
    if channel is None:
        raise ValueError("RSS channel missing")
    output = []
    for item in channel.findall("item"):
        raw_date = item.findtext("pubDate")
        published = parsedate_to_datetime(raw_date) if raw_date else None
        if published is not None and published.utcoffset() is None:
            raise ValueError("publication time needs an offset")
        output.append({
            "id": item.findtext("guid") or item.findtext("link"),
            "headline": item.findtext("title"),
            "original_url": item.findtext("link"),
            "issuer_name": item.findtext(DC + "contributor"),
            "language": item.findtext(DC + "language"),
            "published_at": published.astimezone(timezone.utc).isoformat() if published else None,
            "body_status": "not_requested",
        })
    return output

fixture = b"""<rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/">
<channel><item><guid>fixture-1</guid><title>Synthetic release</title>
<link>https://example.com/release</link><pubDate>Sat, 14 Nov 2026 12:00:00 -0500</pubDate>
<dc:contributor>Example issuer</dc:contributor><dc:language>en-US</dc:language>
</item></channel></rss>"""
records = parse_release_feed(fixture)
assert records[0]["published_at"] == "2026-11-14T17:00:00+00:00"
assert records[0]["issuer_name"] == "Example issuer"
assert records[0]["body_status"] == "not_requested"
print("synthetic RSS fixture passed")