GRO-2294: Route Optimization security hardening (LOW)

Two defense-in-depth fixes from the GRO-2162 feature-level security review:

1. Enforce the documented ?limit cap on POST /api/clients/geocode-batch.
   The handler now clamps limit to GEOCODE_BATCH_MAX_LIMIT (500) after the
   positive-integer check, bounding synchronous request duration and per-request
   external API cost when routeOptimizationProvider = "google".

2. Redact the encrypted googleMapsApiKey from GET /api/admin/settings on both
   the existing-row and auto-create branches. The ciphertext is never needed
   client-side and is now stripped via redactSettings().

Adds route-level tests for the limit clamp (default/passthrough/clamp/floor/
reject) and the settings redaction (both branches). Updates UAT_PLAYBOOK.md
TC-API-2.13a and TC-API-13.1.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

UAT_PLAYBOOK.md

@@ -133,6 +133,7 @@ Geocoding turns a client's street address into `latitude`/`longitude` + `geocode
 | TC-API-2.11 | Geocode endpoint is manager-only | As **groomer** or **receptionist**, `POST /api/clients/{id}/geocode` | 403 Forbidden (role not permitted) |
 | TC-API-2.12 | Batch geocode un-geocoded clients | As manager, `POST /api/clients/geocode-batch?limit=10` on a DB with un-geocoded clients | 200 OK; body `{ provider, processed, geocoded, unresolved, errors, remaining, outcomes[] }`. `processed` ≤ 10; `remaining` reflects un-geocoded clients beyond this batch. Re-run while `remaining > 0` to finish (throttled to provider rate limit) |
 | TC-API-2.13 | Batch geocode — invalid limit | As manager, `POST /api/clients/geocode-batch?limit=0` (or non-numeric) | 400 `{ error: "limit must be a positive integer" }` |
+| TC-API-2.13a | Batch geocode — `?limit` cap enforced (GRO-2294) | As manager, `POST /api/clients/geocode-batch?limit=100000` on a DB with un-geocoded clients | 200 OK; the request is **clamped to the documented max of 500** — `processed` ≤ 500 (never the raw 100000). A fractional `?limit` (e.g. `49.9`) is floored to `49`. Confirms a manager cannot hold one synchronous request open / accrue unbounded Google API cost via an oversized limit |
 | TC-API-2.14 | Batch geocode — manager-only | As groomer/receptionist, `POST /api/clients/geocode-batch` | 403 Forbidden |
 | TC-API-2.15 | Auto-geocode on create | As manager/receptionist, `POST /api/clients` with a valid `address` | 201 Created; response includes a `geocoding` object (`status: "geocoded"` for a resolvable address) and the persisted client carries `latitude`/`longitude`/`geocodedAt`. Creating without an address succeeds with no `geocoding` field |
 | TC-API-2.16 | Auto-geocode on address update | As manager/receptionist, `PATCH /api/clients/{id}` changing `address` to a new valid value | 200 OK; response includes a `geocoding` object and refreshed coordinates. Patching unrelated fields (e.g. `name`) does NOT re-geocode (no `geocoding` field) |
@@ -331,7 +332,7 @@ This means:
 
 | # | Scenario | Steps | Expected |
 |---|----------|-------|----------|
-| TC-API-13.1 | Get business settings | GET /api/admin/settings | 200 OK, business settings returned |
+| TC-API-13.1 | Get business settings | GET /api/admin/settings | 200 OK, business settings returned. Response body **must NOT include `googleMapsApiKey`** — the encrypted secret is redacted from the projection (GRO-2294, defense-in-depth); non-secret fields (`businessName`, colors, `routeOptimizationProvider`, etc.) are still present |
 | TC-API-13.2 | Update business settings | PATCH /api/admin/settings with updated values | 200 OK, settings updated |
 | TC-API-13.3 | Upload logo | POST /api/admin/settings/logo/upload with file | 200 OK, logo uploaded and stored |
 | TC-API-13.4 | View logo | GET /api/admin/settings/logo | 200 OK, logo image returned |

src/__tests__/geocodeBatchLimit.test.ts

@@ -0,0 +1,89 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { Hono } from "hono";
+
+// ─── Mocks ──────────────────────────────────────────────────────────────────
+// GRO-2294: the POST /clients/geocode-batch handler must clamp ?limit to the
+// documented maximum (500) before invoking the geocoding service. We mock the
+// service to capture the exact limit the route forwards.
+
+const geocodeUngeocodedClients = vi.fn(async () => ({
+  totalRemaining: 0,
+  processed: 0,
+  geocoded: 0,
+  failed: 0,
+  remaining: 0,
+}));
+
+vi.mock("../services/clientGeocoding.js", () => ({
+  geocodeUngeocodedClients,
+  geocodeClient: vi.fn(),
+  resolveClientGeocodingProvider: vi.fn(),
+}));
+
+vi.mock("@groombook/db", () => {
+  const tableProxy = (name: string) =>
+    new Proxy(
+      { _name: name },
+      { get: (_t, p) => (p === "_name" ? name : { table: name, column: p }) }
+    );
+  return {
+    getDb: () => ({}),
+    clients: tableProxy("clients"),
+    appointments: tableProxy("appointments"),
+    and: vi.fn(),
+    eq: vi.fn(),
+    or: vi.fn(),
+    exists: vi.fn(),
+  };
+});
+
+const { clientsRouter } = await import("../routes/clients.js");
+
+const app = new Hono();
+app.route("/clients", clientsRouter);
+
+function postBatch(query: string) {
+  return app.request(`/clients/geocode-batch${query}`, { method: "POST" });
+}
+
+describe("POST /clients/geocode-batch — ?limit cap (GRO-2294)", () => {
+  beforeEach(() => {
+    geocodeUngeocodedClients.mockClear();
+  });
+
+  it("defaults to 50 when no ?limit is supplied", async () => {
+    const res = await postBatch("");
+    expect(res.status).toBe(200);
+    expect(geocodeUngeocodedClients).toHaveBeenCalledWith(expect.anything(), 50);
+  });
+
+  it("passes through a value within the cap", async () => {
+    const res = await postBatch("?limit=120");
+    expect(res.status).toBe(200);
+    expect(geocodeUngeocodedClients).toHaveBeenCalledWith(expect.anything(), 120);
+  });
+
+  it("clamps an over-cap value to 500", async () => {
+    const res = await postBatch("?limit=100000");
+    expect(res.status).toBe(200);
+    expect(geocodeUngeocodedClients).toHaveBeenCalledWith(expect.anything(), 500);
+  });
+
+  it("floors a fractional value before clamping", async () => {
+    const res = await postBatch("?limit=49.9");
+    expect(res.status).toBe(200);
+    expect(geocodeUngeocodedClients).toHaveBeenCalledWith(expect.anything(), 49);
+  });
+
+  it("rejects a non-positive limit with 400", async () => {
+    const res = await postBatch("?limit=0");
+    expect(res.status).toBe(400);
+    expect(geocodeUngeocodedClients).not.toHaveBeenCalled();
+  });
+
+  it("rejects a non-numeric limit with 400", async () => {
+    const res = await postBatch("?limit=abc");
+    expect(res.status).toBe(400);
+    expect(geocodeUngeocodedClients).not.toHaveBeenCalled();
+  });
+});

src/__tests__/settings.test.ts

@@ -0,0 +1,91 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { Hono } from "hono";
+
+// ─── Mocks ──────────────────────────────────────────────────────────────────
+// GRO-2294: GET /api/admin/settings must not return the encrypted
+// googleMapsApiKey ciphertext, on either the existing-row or auto-create branch.
+
+let selectRows: Record<string, unknown>[] = [];
+let insertReturning: Record<string, unknown>[] = [];
+
+function makeChainable(data: unknown[]): unknown {
+  const arr = [...data];
+  const chain = new Proxy(arr, {
+    get(target, prop) {
+      if (prop === "where" || prop === "orderBy" || prop === "limit") {
+        return () => chain;
+      }
+      // @ts-expect-error proxy passthrough
+      return target[prop];
+    },
+  });
+  return chain;
+}
+
+vi.mock("@groombook/db", () => {
+  const businessSettings = new Proxy(
+    { _name: "business_settings" },
+    { get: (_t, p) => (p === "_name" ? "business_settings" : { column: p }) }
+  );
+  return {
+    getDb: () => ({
+      select: () => ({ from: () => makeChainable(selectRows) }),
+      insert: () => ({
+        values: () => ({ returning: () => insertReturning }),
+      }),
+    }),
+    businessSettings,
+    eq: vi.fn(),
+  };
+});
+
+vi.mock("../lib/s3.js", () => ({
+  getPresignedUploadUrl: vi.fn(),
+  deleteObject: vi.fn(),
+  putObject: vi.fn(),
+  getObject: vi.fn(),
+}));
+
+const { settingsRouter } = await import("../routes/settings.js");
+
+const app = new Hono();
+app.route("/settings", settingsRouter);
+
+const FULL_ROW = {
+  id: "settings-uuid-1",
+  businessName: "GroomBook",
+  primaryColor: "#4f8a6f",
+  accentColor: "#8b7355",
+  routeOptimizationProvider: "google",
+  googleMapsApiKey: "ENCRYPTED::super-secret-ciphertext",
+  createdAt: new Date(),
+  updatedAt: new Date(),
+};
+
+describe("GET /settings — googleMapsApiKey redaction (GRO-2294)", () => {
+  beforeEach(() => {
+    selectRows = [];
+    insertReturning = [];
+  });
+
+  it("omits googleMapsApiKey from an existing settings row", async () => {
+    selectRows = [{ ...FULL_ROW }];
+    const res = await app.request("/settings", { method: "GET" });
+    expect(res.status).toBe(200);
+    const body = (await res.json()) as Record<string, unknown>;
+    expect(body).not.toHaveProperty("googleMapsApiKey");
+    // Non-secret fields are still returned.
+    expect(body.businessName).toBe("GroomBook");
+    expect(body.routeOptimizationProvider).toBe("google");
+  });
+
+  it("omits googleMapsApiKey from the auto-create branch", async () => {
+    selectRows = [];
+    insertReturning = [{ ...FULL_ROW, id: "settings-uuid-new" }];
+    const res = await app.request("/settings", { method: "GET" });
+    expect(res.status).toBe(200);
+    const body = (await res.json()) as Record<string, unknown>;
+    expect(body).not.toHaveProperty("googleMapsApiKey");
+    expect(body.id).toBe("settings-uuid-new");
+  });
+});

src/routes/clients.ts

@@ -12,6 +12,12 @@ import {
 
 export const clientsRouter = new Hono<AppEnv>();
 
+// Batch-geocode bounds (GRO-2294): default 50, hard cap 500. The cap bounds how
+// long one synchronous request stays open and the per-request external API cost
+// when routeOptimizationProvider = "google".
+const GEOCODE_BATCH_DEFAULT_LIMIT = 50;
+const GEOCODE_BATCH_MAX_LIMIT = 500;
+
 type ClientRow = typeof clients.$inferSelect;
 
 /**
@@ -185,12 +191,15 @@ clientsRouter.post("/:clientId/geocode", async (c) => {
 clientsRouter.post("/geocode-batch", async (c) => {
   const db = getDb();
   const limitRaw = c.req.query("limit");
-  let limit = 50;
+  let limit = GEOCODE_BATCH_DEFAULT_LIMIT;
   if (limitRaw !== undefined) {
     limit = Number(limitRaw);
     if (!Number.isFinite(limit) || limit <= 0) {
       return c.json({ error: "limit must be a positive integer" }, 400);
     }
+    // Clamp to the documented maximum to bound synchronous request duration
+    // and (for the Google provider) per-request external API cost.
+    limit = Math.min(Math.floor(limit), GEOCODE_BATCH_MAX_LIMIT);
   }
   const summary = await geocodeUngeocodedClients(db, limit);
   return c.json(summary);

src/routes/settings.ts

@@ -7,6 +7,17 @@ import { requireSuperUser } from "../middleware/rbac.js";
 
 export const settingsRouter = new Hono();
 
+type BusinessSettingsRow = typeof businessSettings.$inferSelect;
+
+// Strip the encrypted googleMapsApiKey ciphertext from settings responses
+// (GRO-2294, defense-in-depth). The secret is never needed client-side; it is
+// only written via the dedicated provider-config endpoint.
+function redactSettings(row: BusinessSettingsRow) {
+  const rest: Partial<BusinessSettingsRow> = { ...row };
+  delete rest.googleMapsApiKey;
+  return rest;
+}
+
 // GET /api/admin/settings — return current business settings
 settingsRouter.get("/", async (c) => {
   const db = getDb();
@@ -14,9 +25,10 @@ settingsRouter.get("/", async (c) => {
   if (!row) {
     // Auto-create default settings if none exist
     const [created] = await db.insert(businessSettings).values({}).returning();
-    return c.json(created);
+    if (!created) throw new Error("Failed to create default settings");
+    return c.json(redactSettings(created));
   }
-  return c.json(row);
+  return c.json(redactSettings(row));
 });
 
 const hexColorRegex = /^#[0-9a-fA-F]{6}$/;