Add feed discovery plugin

plugins/feed-discovery/src/output/rss.ts

@@ -0,0 +1,25 @@
+import RSS from "rss";
+import type { FeedDiscoveryResponse } from "../types.js";
+
+export function renderRss(response: FeedDiscoveryResponse) {
+  const feed = new RSS({
+    title: `LogicSRC feed discovery: ${response.query}`,
+    description: `Discovered feed sources for ${response.query}`,
+    feed_url: `https://bittorrented.com/rss/discover/${encodeURIComponent(response.normalizedQuery)}.xml`,
+    site_url: "https://bittorrented.com/rss",
+    language: "en"
+  });
+
+  for (const result of response.results) {
+    feed.item({
+      title: result.title,
+      description: result.description ?? `Discovered ${result.kind} feed from ${result.provider}`,
+      url: result.homepageUrl ?? result.feedUrl,
+      guid: result.canonicalFeedUrl ?? result.feedUrl,
+      categories: [result.kind, result.provider, ...result.tags],
+      date: result.lastPublishedAt ? new Date(result.lastPublishedAt) : new Date()
+    });
+  }
+
+  return feed.xml({ indent: true });
+}