nook marketing - utm, analytics, etc

src/routes/api/the-nook/_download.ts

@@ -0,0 +1,75 @@
+import { S3Client, GetObjectCommand } from "@aws-sdk/client-s3";
+import { env } from "~/env/server";
+
+/**
+ * Download resolution for The Nook, kept out of the route module on purpose.
+ *
+ * Vinxi's route tree-shake (`vinxi/lib/plugins/tree-shake.babel.js`) deletes
+ * every exported declaration in a route file whose name is not in the
+ * `?pick=` list the router asks for — and a route is picked as `pick=GET`.
+ * A helper exported from `download.ts` is therefore removed while `GET`
+ * still references it, which fails at runtime with "is not defined" in dev
+ * and in the production bundle alike. Only HTTP handlers may be exported
+ * from a route; helpers live here, where the transform never runs. Same
+ * reason `_lib.ts` exists.
+ */
+
+const APPCast_KEY = "api/TheNook/appcast.xml";
+
+/** Kept in step with the appcast route's own 5-minute cache. */
+const RESOLVE_TTL_MS = 5 * 60 * 1000;
+
+const ENCLOSURE_RE = /<enclosure\b[^>]*\burl="([^"]+)"/gi;
+
+/**
+ * Picks the newest release artifact out of a Sparkle appcast: the first
+ * enclosure that is a .dmg, else the first .zip, else the first enclosure
+ * of any kind. Enclosures appear in newest-first order.
+ */
+export function pickEnclosure(xml: string): string | null {
+  const urls: string[] = [];
+  for (const match of xml.matchAll(ENCLOSURE_RE)) {
+    if (match[1]) urls.push(match[1]);
+  }
+  return (
+    urls.find((u) => /\.dmg(\?|$)/i.test(u)) ??
+    urls.find((u) => /\.zip(\?|$)/i.test(u)) ??
+    urls[0] ??
+    null
+  );
+}
+
+let cached: { url: string; at: number } | null = null;
+
+/** Drops the cached enclosure so the next request re-reads the appcast. */
+export function invalidateDownloadCache(): void {
+  cached = null;
+}
+
+/** Resolves (and briefly caches) the current download URL from the appcast. */
+export async function resolveLatestDownload(): Promise<string | null> {
+  if (cached && Date.now() - cached.at < RESOLVE_TTL_MS) {
+    return cached.url;
+  }
+
+  const client = new S3Client({
+    region: env.AWS_REGION,
+    credentials: {
+      accessKeyId: env.MY_AWS_ACCESS_KEY,
+      secretAccessKey: env.MY_AWS_SECRET_KEY
+    }
+  });
+
+  const response = await client.send(
+    new GetObjectCommand({
+      Bucket: env.VITE_DOWNLOAD_BUCKET_STRING,
+      Key: APPCast_KEY
+    })
+  );
+  if (!response.Body) return null;
+
+  const xml = await response.Body.transformToString();
+  const url = pickEnclosure(xml);
+  if (url) cached = { url, at: Date.now() };
+  return url;
+}

src/routes/api/the-nook/download.test.ts

@@ -0,0 +1,202 @@
+import { describe, expect, it, mock, beforeEach } from "bun:test";
+
+// The route's contracts:
+//   1. Every click is recorded through the shared analytics buffer with the
+//      path, referrer, country and device type the funnel needs.
+//   2. The response is a no-store 302 to the newest release enclosure, so a
+//      CDN can never serve a later click without it reaching this handler.
+//   3. An unreadable appcast degrades to 503 — but the click is still logged,
+//      because a failed download is exactly the event worth seeing.
+
+type Entry = Record<string, unknown>;
+const logged: Entry[] = [];
+let appcastXml = "";
+let s3ShouldThrow = false;
+let flushCalls = 0;
+
+mock.module("~/env/server", () => ({
+  env: {
+    AWS_REGION: "us-east-1",
+    MY_AWS_ACCESS_KEY: "test-key",
+    MY_AWS_SECRET_KEY: "test-secret",
+    VITE_DOWNLOAD_BUCKET_STRING: "test-bucket"
+  }
+}));
+
+mock.module("@aws-sdk/client-s3", () => ({
+  S3Client: class {
+    async send() {
+      if (s3ShouldThrow) throw new Error("s3 unavailable");
+      return {
+        Body: appcastXml
+          ? { transformToString: async () => appcastXml }
+          : null
+      };
+    }
+  },
+  GetObjectCommand: class {
+    input: unknown;
+    constructor(input: unknown) {
+      this.input = input;
+    }
+  }
+}));
+
+mock.module("vinxi/http", () => ({
+  getRequestIP: () => null
+}));
+
+mock.module("~/server/analytics", () => ({
+  logVisit: async (entry: Entry) => {
+    logged.push(entry);
+  },
+  // The route must flush, not merely buffer: the batch timer is not
+  // guaranteed to survive the response on serverless.
+  flushAnalytics: async () => {
+    flushCalls += 1;
+  },
+  // Mirrors the real enrichment contract: deviceType is derived from the UA.
+  enrichAnalyticsEntry: (entry: Entry) => ({
+    ...entry,
+    deviceType: String(entry.userAgent ?? "").includes("Macintosh")
+      ? "desktop"
+      : null
+  })
+}));
+
+const { GET } = await import("./download");
+const { pickEnclosure, invalidateDownloadCache } = await import("./_download");
+
+const DMG = "https://cdn.example/TheNook-0.6.3.dmg";
+const ZIP = "https://cdn.example/TheNook-0.6.3.zip";
+
+const appcast = (urls: string[]) =>
+  `<?xml version="1.0"?><rss><channel><item>` +
+  urls
+    .map(
+      (u) =>
+        `<enclosure url="${u}" sparkle:version="1" length="1" type="application/octet-stream"/>`
+    )
+    .join("") +
+  `</item></channel></rss>`;
+
+function request(headers: Record<string, string> = {}, query = "") {
+  return {
+    request: new Request(
+      `https://nook.freno.me/api/the-nook/download${query}`,
+      { headers }
+    ),
+    nativeEvent: {}
+  } as never;
+}
+
+const MAC_UA =
+  "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15";
+
+beforeEach(() => {
+  logged.length = 0;
+  appcastXml = appcast([DMG, ZIP]);
+  s3ShouldThrow = false;
+  flushCalls = 0;
+  invalidateDownloadCache();
+});
+
+describe("GET /api/the-nook/download", () => {
+  it("logs the click and 302s to the newest dmg", async () => {
+    const res = await GET(request({ referer: "https://nook.freno.me/" }));
+
+    expect(res.status).toBe(302);
+    expect(res.headers.get("Location")).toBe(DMG);
+    expect(res.headers.get("Cache-Control")).toBe("no-store");
+
+    expect(logged.length).toBe(1);
+    expect(logged[0]).toMatchObject({
+      path: "/api/the-nook/download",
+      method: "GET",
+      referrer: "https://nook.freno.me/"
+    });
+    // Flushed within the request, not left to the batch timer.
+    expect(flushCalls).toBe(1);
+  });
+
+  it("derives the device type from the user agent", async () => {
+    await GET(request({ "user-agent": MAC_UA }));
+    expect(logged[0]!.deviceType).toBe("desktop");
+  });
+
+  it("records the edge country, and lets ?c= override it", async () => {
+    await GET(request({ "x-vercel-ip-country": "GB" }));
+    expect(logged[0]!.country).toBe("GB");
+
+    invalidateDownloadCache();
+    await GET(request({ "cf-ipcountry": "DE" }));
+    expect(logged[1]!.country).toBe("DE");
+
+    invalidateDownloadCache();
+    await GET(request({ "x-vercel-ip-country": "GB" }, "?c=JP"));
+    expect(logged[2]!.country).toBe("JP");
+  });
+
+  it("falls back to the forwarded address when no request IP is available", async () => {
+    await GET(request({ "x-forwarded-for": "198.51.100.9, 10.0.0.1" }));
+    expect(logged[0]!.ipAddress).toBe("198.51.100.9");
+  });
+
+  it("still logs the click when the appcast cannot be read", async () => {
+    s3ShouldThrow = true;
+    const res = await GET(request());
+
+    expect(res.status).toBe(503);
+    expect(res.headers.get("Cache-Control")).toBe("no-store");
+    expect(logged.length).toBe(1);
+  });
+
+  it("503s when the appcast carries no enclosure", async () => {
+    appcastXml = "<?xml version='1.0'?><rss><channel></channel></rss>";
+    invalidateDownloadCache();
+
+    const res = await GET(request());
+    expect(res.status).toBe(503);
+  });
+
+  it("captures campaign tags from the click URL and the referer", async () => {
+    await GET(
+      request(
+        { referer: "https://nook.freno.me/?utm_source=hn&utm_campaign=launch" },
+        "?utm_medium=post"
+      )
+    );
+
+    expect(logged[0]).toMatchObject({
+      utmSource: "hn",
+      utmMedium: "post",
+      utmCampaign: "launch"
+    });
+  });
+
+  it("logs nulls when nothing is tagged", async () => {
+    await GET(request({ referer: "https://nook.freno.me/" }));
+    expect(logged[0]).toMatchObject({
+      utmSource: null,
+      utmMedium: null,
+      utmCampaign: null
+    });
+  });
+});
+
+describe("pickEnclosure", () => {
+  it("prefers a dmg over a zip even when the zip comes first", () => {
+    expect(pickEnclosure(appcast([ZIP, DMG]))).toBe(DMG);
+  });
+
+  it("falls back to a zip, then to any enclosure", () => {
+    expect(pickEnclosure(appcast([ZIP]))).toBe(ZIP);
+    expect(pickEnclosure(appcast(["https://cdn.example/notes.txt"]))).toBe(
+      "https://cdn.example/notes.txt"
+    );
+  });
+
+  it("returns null when there is no enclosure", () => {
+    expect(pickEnclosure("<rss><channel></channel></rss>")).toBeNull();
+  });
+});

src/routes/api/the-nook/download.ts

@@ -0,0 +1,94 @@
+import type { APIEvent } from "@solidjs/start/server";
+import { getRequestIP } from "vinxi/http";
+import { logVisit, enrichAnalyticsEntry, flushAnalytics } from "~/server/analytics";
+import { parseUtm } from "~/server/utm";
+import { resolveLatestDownload } from "./_download";
+
+/**
+ * GET /api/the-nook/download
+ *
+ * The measured download door. Both hero buttons point here instead of
+ * resolving the appcast in the browser: this route resolves the latest
+ * release enclosure server-side, records the click through the shared
+ * analytics buffer, then 302s to the DMG.
+ *
+ * Why a redirect and not a direct S3 link: the appcast route and the DMG
+ * route never logged anything, so step 2 of the funnel (download click →
+ * DMG served) was invisible. Every click now lands one row in
+ * VisitorAnalytics under the path below, which is what `topApiCalls`
+ * already surfaces.
+ *
+ * Country is read from the edge headers Vercel/Cloudflare set; the
+ * analytics buffer carries a `country` column that nothing populated
+ * until now. `?c=` is accepted as an override for previews and manual
+ * verification.
+ *
+ * ONLY the handler is exported here: Vinxi's route tree-shake deletes
+ * exported declarations that are not in the router's `pick=` list, so a
+ * helper exported from this file would be removed while `GET` still
+ * referenced it. All resolution helpers live in `./_download.ts`.
+ */
+
+function firstHeader(request: Request, ...names: string[]): string | null {
+  for (const name of names) {
+    const value = request.headers.get(name);
+    if (value) return value;
+  }
+  return null;
+}
+
+export async function GET(event: APIEvent): Promise<Response> {
+  const { request } = event;
+  const url = new URL(request.url);
+
+  const forwarded = firstHeader(request, "x-forwarded-for");
+  const ipAddress =
+    getRequestIP(event.nativeEvent) ??
+    (forwarded ? forwarded.split(",")[0]!.trim() : null);
+
+  // Best-effort: a failed analytics write must never block a download.
+  // Flushed (not merely buffered) because a download click is low-volume and
+  // the batch timer is not guaranteed to survive the response on serverless.
+  try {
+    const referrer = firstHeader(request, "referer", "referrer");
+    await logVisit(
+      enrichAnalyticsEntry({
+        path: "/api/the-nook/download",
+        method: "GET",
+        referrer,
+        userAgent: firstHeader(request, "user-agent"),
+        ipAddress,
+        // The click carries its own tags when a campaign links straight here;
+        // otherwise the landing page's tags ride along in the referer.
+        ...parseUtm(request.url, referrer),
+        country:
+          url.searchParams.get("c") ??
+          firstHeader(request, "x-vercel-ip-country", "cf-ipcountry")
+      })
+    );
+    await flushAnalytics();
+  } catch (error) {
+    console.error("Failed to log download click:", error);
+  }
+
+  let target: string | null = null;
+  try {
+    target = await resolveLatestDownload();
+  } catch (error) {
+    console.error("Failed to resolve Nook download:", error);
+  }
+
+  if (!target) {
+    return new Response("Download unavailable", {
+      status: 503,
+      headers: { "Content-Type": "text/plain", "Cache-Control": "no-store" }
+    });
+  }
+
+  // No-store is load-bearing: a cached 302 would serve later clicks without
+  // ever reaching this handler, silently dropping them from the funnel.
+  return new Response(null, {
+    status: 302,
+    headers: { Location: target, "Cache-Control": "no-store" }
+  });
+}

src/routes/nook/index.tsx

@@ -9,19 +9,14 @@ import { createSignal, Show } from "solid-js";
 import { useDarkMode } from "~/context/darkMode";
 import { useSite } from "~/context/SiteContext";
 
-/* The appcast's first enclosure always names the latest release dmg. */
-async function downloadNook() {
-  try {
-    const res = await fetch("/api/TheNook/appcast.xml");
-    const xml = await res.text();
-    const url =
-      xml.match(/<enclosure url="([^"]+\.dmg)"/)?.[1] ??
-      xml.match(/<enclosure url="([^"]+\.zip)"/)?.[1];
-    if (!url) throw new Error("no enclosure");
-    window.location.href = url;
-  } catch {
-    console.error("Could not resolve latest Nook download");
-  }
+/*
+ * Downloads are logged and resolved server-side. `/api/the-nook/download`
+ * records the click in the analytics buffer, then 302s to the latest
+ * release dmg the appcast names. Pointing the button straight at the
+ * enclosure would skip the funnel's second step entirely.
+ */
+function downloadNook() {
+  window.location.href = "/api/the-nook/download";
 }
 
 export default function NookLanding() {