InkNote/e2e/offline.mjs

/* Reading without a connection.
 *
 * The claim being tested is the one the app makes by being a PWA at all: a note
 * you have seen is a note you can still read on a train. That has two halves,
 * and both have to hold — the application itself has to load from the cache, and
 * the notes have to already be on the device rather than one request away.
 *
 * "Offline" here means the browser context is switched offline, which is what
 * losing a connection actually looks like to the page: requests fail, the
 * service worker still answers, IndexedDB still works.
 */
import {
  api,
  check,
  createNote,
  createNotebook,
  launch,
  report,
  search,
  setTitle,
  typeInEditor,
  withFreshUser,
} from "./lib.mjs";

const browser = await launch();
let session;
try {
  session = await withFreshUser(browser, "offline");
  const p = session.page;
  const context = p.context();

  await createNotebook(p, "Unterwegs");
  await p.locator("button").filter({ hasText: "Unterwegs" }).first().click();
  await p.waitForTimeout(700);

  for (const [title, body] of [
    ["Reiseplan", "Abfahrt um sieben Uhr vom Hauptbahnhof."],
    ["Einkauf", "Milch, Brot, Kaffee."],
  ]) {
    await createNote(p);
    await setTitle(p, title);
    await typeInEditor(p, body);
    await p.waitForTimeout(900);
  }

  /* The service worker has to be in charge before it can answer anything. */
  const controlled = await p.evaluate(async () => {
    if (!("serviceWorker" in navigator)) return "unsupported";
    const reg = await navigator.serviceWorker.ready;
    return reg.active ? "active" : "no active worker";
  });
  check(controlled === "active", "a service worker is installed and running", controlled);

  /* Bodies reach the device on demand, so a note never opened would not be
     readable offline. The background backfill exists for exactly that; give it
     a moment and then confirm every note is really in local storage. */
  await p.waitForTimeout(4000);
  const cached = await p.evaluate(
    () =>
      new Promise((resolve) => {
        const open = indexedDB.open("inknote");
        open.onerror = () => resolve({ error: String(open.error) });
        open.onsuccess = () => {
          const idb = open.result;
          if (!idb.objectStoreNames.contains("noteContents")) return resolve({ error: "no store" });
          const tx = idb.transaction("noteContents", "readonly");
          const all = tx.objectStore("noteContents").getAll();
          all.onsuccess = () =>
            resolve({
              count: all.result.length,
              texts: all.result.map((r) => String(r.content || "")),
            });
          all.onerror = () => resolve({ error: String(all.error) });
        };
      })
  );
  check(!cached.error, "the local copy of the notes can be read", cached.error || "");
  check(cached.count >= 2, "every note's body is on the device, not only the open one", `${cached.count} bodies`);
  check(
    cached.texts.some((t) => t.includes("Hauptbahnhof")),
    "including one that was written earlier and then left"
  );

  /* ── pull the plug ── */
  await context.setOffline(true);
  await p.waitForTimeout(500);

  const blocked = await p.evaluate(async () => {
    try {
      await fetch("/api/notes", { cache: "no-store" });
      return "still answering";
    } catch {
      return "blocked";
    }
  });
  check(blocked === "blocked", "the network really is gone", blocked);

  /* A cold start: not a soft re-render, a full page load with no connection. */
  await p.reload({ waitUntil: "domcontentloaded" }).catch(() => {});
  await p.waitForTimeout(4000);

  const loaded = await p.locator("body").innerText();
  check(loaded.length > 40, "the app itself loads from the cache with no connection", `${loaded.length} chars`);
  check(!/Sign In/i.test(loaded), "and the session is still there — no login screen offline");

  await p.locator("button").filter({ hasText: "Unterwegs" }).first().click();
  await p.waitForTimeout(1500);
  const rows = await p.locator("[data-note-row]").count();
  check(rows >= 2, "the notebook still lists its notes", `${rows} rows`);

  await p.locator("[data-note-row]").filter({ hasText: "Reiseplan" }).first().click();
  await p.waitForTimeout(2500);
  const body = await p.locator(".ProseMirror").innerText();
  check(body.includes("Hauptbahnhof"), "and a note opens with its text", JSON.stringify(body.slice(0, 60)));

  /* Searching is local by design — the server holds only ciphertext — so it has
     to keep working when the server is not there at all. */
  await search(p, "Kaffee");
  const hits = await p.locator("[data-note-row]").count();
  check(hits === 1, "search still finds a note by its text, offline", `${hits} hits`);
  await search(p, "");

  /* Writing offline is queued, not lost. */
  await p.locator("[data-note-row]").filter({ hasText: "Einkauf" }).first().click();
  await p.waitForTimeout(1800);
  await p.locator(".ProseMirror").click();
  await p.keyboard.press("Control+End");
  await p.keyboard.type(" Und Butter.");
  await p.waitForTimeout(2500);

  const status = await p.locator("body").innerText();
  check(/offline|Pending|Wartet|Änderungen/i.test(status), "the app says it is offline rather than pretending");

  /* ── back on ── */
  await context.setOffline(false);
  await p.waitForTimeout(1000);
  await p.evaluate(() => window.dispatchEvent(new Event("online")));
  await p.waitForTimeout(8000);

  const server = (await api(p, "GET", "/notes")).body;
  const einkauf = server.find((n) => n.title === "Einkauf");
  const stored = await api(p, "GET", `/notes/${einkauf.id}`);
  check(
    String(stored.body.content).includes("Butter"),
    "and the edit made offline reaches the server once there is a connection",
    String(stored.body.content).slice(0, 80)
  );
} catch (e) {
  check(false, "suite ran to the end", e.message);
} finally {
  await session?.cleanup();
  const code = report();
  await browser.close();
  process.exit(code);
}