feat: equivalent CF worker implementation for proxy + deployment

fix: ensure CORS headers

.github/workflows/main.yml

@@ -93,6 +93,26 @@ jobs:
         with:
           name: build-artifacts
           path: dist
+  deploy-functions:
+    runs-on: ubuntu-latest
+    name: Deploy functions
+    needs: build-app
+    steps:
+      - uses: actions/checkout@v4
+      - name: Yarn cache
+        uses: actions/cache@v4
+        id: yarn-cache-restore
+        with:
+          path: |
+            .yarn
+          key: ${{ runner.os }}-${{ hashFiles('**/yarn.lock') }}-${{ env.NODE_VERSION }}
+      - run: |
+          . script/bootstrap.sh
+      - uses: cloudflare/wrangler-action@v3
+        with:
+          apiToken: ${{ secrets.CLOUDFLARE_API_TOKEN }}
+          accountId: ${{ secrets.CLOUDFLARE_ACCOUNT_ID }}
+          command: deploy --name=rss-reader-proxy --minify ./functions/rss-proxy/rss-proxy-cloudflare.mts 
   preview:
     runs-on: ubuntu-latest
     name: Deploy preview

functions/rss-proxy/rss-proxy-cloudflare.mts

@@ -0,0 +1,59 @@
+/*
+ * Fetches and parses RSS feeds.
+ *
+ * This handles the fetching, XML parsing and formatting of
+ * RSS feed data so that the frontent clients do not have to.
+ *
+ * This is operating on a "by-feed" basis such that each
+ * run only processes one feed, and the clients are expected
+ * to make multiple requests if they have a list of feeds to
+ * follow.
+ */
+
+import { parseFeed } from "htmlparser2";
+
+const defaultHeaders = {
+	"Access-Control-Allow-Origin": "https://rss-reader.karnov.club",
+};
+
+function processFeedXML(feed) {
+	return {
+		title: feed.title,
+		lastPull: String(Date.now()),
+		items: feed.items.reduce((items, feedItem) => {
+			items.push({
+				title: feedItem.title,
+				url: feedItem.link,
+				published: new Date(feedItem.pubDate),
+			});
+
+			return items;
+		}, []),
+	};
+}
+
+async function fetchHandler(request: Request) {
+	const requestUrl = new URL(request.url);
+	const proxiedUrl = requestUrl.searchParams.get("url");
+	try {
+		const responseData = await fetch(proxiedUrl);
+		const data = await responseData.text();
+		const newFeedData = parseFeed(data);
+		const newFeed = processFeedXML(newFeedData);
+		const mergedFeeds = newFeed;
+
+		return new Response(JSON.stringify(mergedFeeds), {
+			status: 200,
+			headers: defaultHeaders,
+		});
+	} catch (error) {
+		return new Response(error.toString(), {
+			status: 500,
+			headers: defaultHeaders,
+		});
+	}
+}
+
+export default {
+	fetch: fetchHandler,
+};

wrangler.toml

@@ -0,0 +1 @@
+compatibility_date = "2024-03-18"