phase 6: web storage layer (KeyStore, Cache, session)

KeyStore + Cache TS interfaces with WebCrypto non-extractable Ed25519 keys persisted via IndexedDB (idb), plus thin api/session.ts that loads or creates the device session at app startup. Vitest unit tests under fake-indexeddb cover both adapters; Playwright e2e verifies the keypair survives reload and produces signatures still verifiable under the persisted public key (gateway round-trip moves to Phase 7's existing acceptance bullet). Browser baseline: WebCrypto Ed25519 — Chrome >=137, Firefox >=130, Safari >=17.4. No JS fallback; ui/docs/storage.md documents the matrix and the WebKit non-determinism quirk. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-05-07 14:08:09 +02:00
parent 87a6694e2d
commit ecd2bc9348
18 changed files with 1133 additions and 29 deletions
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+// `session.ts` is the thin layer that loads or creates the device
+// session at app startup. The keypair half is always materialised
+// (loaded from the [KeyStore], or freshly generated when the slot is
+// empty); the device-session-id half is read out of the [Cache] and
+// is `null` until Phase 7's confirm-email-code handler stores it via
+// [setDeviceSessionId]. A `null` deviceSessionId is the marker that
+// the user must run the email-code login flow.
+//
+// Phase 7 wires the production caller (a layout-level loader that
+// runs `loadDeviceSession` on first render and forwards the result
+// into the Svelte session store). Phase 6 ships the persistence
+// primitives this loader needs.
+
+import type { Cache, DeviceKeypair, KeyStore } from "../platform/store/index";
+
+export const SESSION_NAMESPACE = "session";
+export const SESSION_ID_KEY = "device-session-id";
+
+export interface DeviceSession {
+	keypair: DeviceKeypair;
+	deviceSessionId: string | null;
+}
+
+/**
+ * loadDeviceSession returns the device session for the current
+ * device. The keypair is loaded from `keyStore`; if the slot is
+ * empty, a fresh non-exportable Ed25519 keypair is generated and
+ * persisted. The returned `deviceSessionId` is `null` until Phase 7
+ * registers the public key with the gateway and persists the
+ * resulting id via [setDeviceSessionId].
+ */
+export async function loadDeviceSession(
+	keyStore: KeyStore,
+	cache: Cache,
+): Promise<DeviceSession> {
+	const existing = await keyStore.load();
+	const keypair = existing ?? (await keyStore.generate());
+	const stored = await cache.get<string>(SESSION_NAMESPACE, SESSION_ID_KEY);
+	return { keypair, deviceSessionId: stored ?? null };
+}
+
+/**
+ * setDeviceSessionId persists the device-session id returned by the
+ * gateway's confirm-email-code response so subsequent app starts can
+ * resume the session without re-login.
+ */
+export async function setDeviceSessionId(
+	cache: Cache,
+	deviceSessionId: string,
+): Promise<void> {
+	await cache.put(SESSION_NAMESPACE, SESSION_ID_KEY, deviceSessionId);
+}
+
+/**
+ * clearDeviceSession wipes both the device keypair and the stored
+ * device-session id. The next [loadDeviceSession] call will generate
+ * a fresh keypair and report `deviceSessionId: null`, forcing
+ * re-login. Used by user-driven logout and by gateway-driven
+ * revocation paths.
+ */
+export async function clearDeviceSession(
+	keyStore: KeyStore,
+	cache: Cache,
+): Promise<void> {
+	await Promise.all([
+		keyStore.clear(),
+		cache.delete(SESSION_NAMESPACE, SESSION_ID_KEY),
+	]);
+}