Add RSS feed loader for episode page generation

website_gen/feed.py

@@ -0,0 +1,75 @@
+import html
+import re
+import xml.etree.ElementTree as ET
+from dataclasses import dataclass
+from email.utils import parsedate_to_datetime
+
+ITUNES_NS = {"itunes": "http://www.itunes.com/dtds/podcast-1.0.dtd"}
+
+TAG_RE = re.compile(r"<[^>]+>")
+WHITESPACE_RE = re.compile(r"\s+")
+
+
+@dataclass
+class Episode:
+    number: int | None
+    slug: str
+    title: str
+    description: str
+    published_iso: str
+    duration_seconds: int | None
+    audio_url: str
+
+
+def parse_feed(xml_text: str) -> list[Episode]:
+    """Turn RSS feed XML into Episode records, skipping items with no usable link."""
+    channel = ET.fromstring(xml_text).find("channel")
+    if channel is None:
+        return []
+
+    episodes: list[Episode] = []
+    for item in channel.findall("item"):
+        slug = _slug_from_link(item.findtext("link"))
+        if not slug:
+            continue
+        enclosure = item.find("enclosure")
+        episodes.append(
+            Episode(
+                number=_as_int(item.findtext("itunes:episode", namespaces=ITUNES_NS)),
+                slug=slug,
+                title=(item.findtext("title") or "").strip(),
+                description=_plain_text(item.findtext("description")),
+                published_iso=_iso_date(item.findtext("pubDate")),
+                duration_seconds=_as_int(item.findtext("itunes:duration", namespaces=ITUNES_NS)),
+                audio_url=(enclosure.get("url") or "") if enclosure is not None else "",
+            )
+        )
+    return episodes
+
+
+def _slug_from_link(link: str | None) -> str:
+    slug = (link or "").strip().rstrip("/")
+    if "/episodes/" not in slug:
+        return ""
+    return slug.rsplit("/episodes/", 1)[-1]
+
+
+def _plain_text(raw: str | None) -> str:
+    text = TAG_RE.sub(" ", raw or "")
+    return WHITESPACE_RE.sub(" ", html.unescape(text)).strip()
+
+
+def _iso_date(raw: str | None) -> str:
+    if not raw:
+        return ""
+    try:
+        return parsedate_to_datetime(raw).isoformat()
+    except (TypeError, ValueError):
+        return ""
+
+
+def _as_int(raw: str | None) -> int | None:
+    try:
+        return int((raw or "").strip())
+    except ValueError:
+        return None