canvas/src/lib/__tests__/hydrate.test.ts

@@ -0,0 +1,213 @@
+// @vitest-environment jsdom
+/**
+ * Tests for canvas/src/lib/hydrate.ts — exponential-backoff canvas store hydration.
+ *
+ * 7 cases:
+ *   1. Success on first attempt → { error: null }
+ *   2. Viewport fetch fails (non-fatal) → store still hydrates, returns { error: null }
+ *   3. Success after 1 retry → onRetrying(1) called once, final result { error: null }
+ *   4. Success after 2 retries → onRetrying called for each failed attempt
+ *   5. All attempts fail → returns the error message after MAX_RETRIES
+ *   6. onRetrying called with correct attempt number on each retry
+ *   7. Exponential backoff delays: 1s, 2s, 4s for attempts 1, 2, 3
+ */
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import { api } from "@/lib/api";
+import { useCanvasStore } from "@/store/canvas";
+import { hydrateCanvas, MAX_RETRIES } from "../hydrate";
+
+// ─── Mock api ──────────────────────────────────────────────────────────────────
+// PLATFORM_URL must be a named export — hydrate.ts imports it directly, not via api.
+vi.mock("@/lib/api", () => ({
+  api: {
+    get: vi.fn<(path: string) => Promise<unknown>>(),
+  },
+  PLATFORM_URL: "http://localhost:8080",
+}));
+
+// ─── Mock store ────────────────────────────────────────────────────────────────
+
+const mockHydrate = vi.fn();
+const mockSetViewport = vi.fn();
+
+vi.mock("@/store/canvas", () => ({
+  useCanvasStore: {
+    getState: () => ({
+      hydrate: mockHydrate,
+      setViewport: mockSetViewport,
+    }),
+  },
+}));
+
+// ─── Helpers ───────────────────────────────────────────────────────────────────
+
+const mockApiGet = vi.mocked(api.get);
+
+function makeWorkspace(id = "ws-1") {
+  return {
+    id,
+    name: "Test WS",
+    role: "assistant",
+    tier: 1,
+    status: "online" as const,
+    agent_card: null,
+    url: "http://localhost:9000",
+    parent_id: null,
+    active_tasks: 0,
+    last_error_rate: 0,
+    last_sample_error: "",
+    uptime_seconds: 60,
+    current_task: "",
+    x: 0,
+    y: 0,
+    collapsed: false,
+    runtime: "",
+    budget_limit: null,
+  };
+}
+
+// ─── Setup / teardown ──────────────────────────────────────────────────────────
+
+beforeEach(() => {
+  vi.clearAllMocks();
+  vi.useFakeTimers();
+});
+
+afterEach(() => {
+  vi.useRealTimers();
+});
+
+// ─── Tests ─────────────────────────────────────────────────────────────────────
+
+describe("hydrateCanvas — success paths", () => {
+  it("returns { error: null } on first-attempt success", async () => {
+    mockApiGet
+      .mockResolvedValueOnce([makeWorkspace()])           // /workspaces
+      .mockResolvedValueOnce({ x: 0, y: 0, zoom: 1 }); // /canvas/viewport
+
+    const result = await hydrateCanvas();
+
+    expect(result).toEqual({ error: null });
+    expect(mockHydrate).toHaveBeenCalledOnce();
+    expect(mockSetViewport).toHaveBeenCalledWith({ x: 0, y: 0, zoom: 1 });
+  });
+
+  it("viewport fetch failure is non-fatal — store still hydrates", async () => {
+    mockApiGet
+      .mockResolvedValueOnce([makeWorkspace()])                            // /workspaces OK
+      .mockRejectedValueOnce(new Error("viewport down"));                   // /canvas/viewport fails
+
+    const result = await hydrateCanvas();
+
+    expect(result).toEqual({ error: null });
+    expect(mockHydrate).toHaveBeenCalledOnce();
+    expect(mockSetViewport).not.toHaveBeenCalled();
+  });
+
+  it("returns { error: null } after 1 retry", async () => {
+    const onRetrying = vi.fn();
+
+    // Each attempt makes 2 parallel api.get calls (workspaces + viewport).
+    // Attempt 1 (fails):  /workspaces → rejected, /viewport → resolved
+    // Attempt 2 (succeeds): /workspaces → resolved, /viewport → resolved
+    mockApiGet
+      .mockRejectedValueOnce(new Error("network down"))     // attempt 1: /workspaces
+      .mockResolvedValueOnce({ x: 0, y: 0, zoom: 1 })     // attempt 1: /viewport
+      .mockResolvedValueOnce([makeWorkspace()])            // attempt 2: /workspaces
+      .mockResolvedValueOnce({ x: 0, y: 0, zoom: 1 });   // attempt 2: /viewport
+
+    const promise = hydrateCanvas(onRetrying);
+
+    // Advance past the first backoff delay (1000 * 2^0 = 1000 ms)
+    await vi.advanceTimersByTimeAsync(1000);
+    await vi.runAllTimersAsync();
+
+    const result = await promise;
+
+    expect(result).toEqual({ error: null });
+    expect(onRetrying).toHaveBeenCalledTimes(1);
+    expect(onRetrying).toHaveBeenCalledWith(1);
+  });
+
+  it("onRetrying called once per failed attempt before next retry", async () => {
+    const onRetrying = vi.fn();
+
+    // Attempt 1: both calls fail
+    // Attempt 2: both calls fail
+    // Attempt 3: both calls succeed → hydrate succeeds
+    mockApiGet
+      .mockRejectedValueOnce(new Error("attempt 1"))     // a1: /workspaces
+      .mockResolvedValueOnce({ x: 0, y: 0, zoom: 1 }) // a1: /viewport (resolved even though workspaces failed)
+      .mockRejectedValueOnce(new Error("attempt 2"))     // a2: /workspaces
+      .mockResolvedValueOnce({ x: 0, y: 0, zoom: 1 }) // a2: /viewport
+      .mockResolvedValueOnce([makeWorkspace()])           // a3: /workspaces
+      .mockResolvedValueOnce({ x: 0, y: 0, zoom: 1 }); // a3: /viewport
+
+    const promise = hydrateCanvas(onRetrying);
+    await vi.runAllTimersAsync();
+
+    const result = await promise;
+
+    expect(result).toEqual({ error: null });
+    expect(onRetrying).toHaveBeenCalledTimes(2);
+    expect(onRetrying).toHaveBeenNthCalledWith(1, 1);
+    expect(onRetrying).toHaveBeenNthCalledWith(2, 2);
+  });
+});
+
+describe("hydrateCanvas — failure paths", () => {
+  it("returns error message after all MAX_RETRIES attempts exhausted", async () => {
+    for (let i = 0; i < MAX_RETRIES; i++) {
+      mockApiGet.mockRejectedValueOnce(new Error(`attempt ${i + 1} failed`));
+    }
+
+    const promise = hydrateCanvas();
+    await vi.runAllTimersAsync();
+    const result = await promise;
+
+    expect(result.error).not.toBeNull();
+    expect(result.error).toContain("Unable to connect to platform");
+    expect(mockHydrate).not.toHaveBeenCalled();
+  });
+
+  it("onRetrying called MAX_RETRIES-1 times before final exhausted attempt", async () => {
+    const onRetrying = vi.fn();
+
+    for (let i = 0; i < MAX_RETRIES; i++) {
+      mockApiGet.mockRejectedValueOnce(new Error(`attempt ${i + 1}`));
+    }
+
+    const promise = hydrateCanvas(onRetrying);
+    await vi.runAllTimersAsync();
+    await promise;
+
+    // onRetrying is called after each failed attempt, before the next attempt.
+    // With MAX_RETRIES=3: called after attempt 1 (→2) and after attempt 2 (→3).
+    expect(onRetrying).toHaveBeenCalledTimes(MAX_RETRIES - 1);
+  });
+});
+
+describe("hydrateCanvas — exponential backoff timing", () => {
+  it("total elapsed time equals sum of exponential delays 1s + 2s + 4s", async () => {
+    const onRetrying = vi.fn();
+
+    for (let i = 0; i < MAX_RETRIES; i++) {
+      mockApiGet.mockRejectedValueOnce(new Error(`attempt ${i + 1}`));
+    }
+
+    const start = Date.now();
+    const promise = hydrateCanvas(onRetrying);
+
+    // Advance all timers at once and let fake timers resolve everything
+    await vi.runAllTimersAsync();
+    await promise;
+
+    const elapsed = Date.now() - start;
+
+    // Total expected: 1000 (delay1) + 2000 (delay2) = 3000 ms
+    // (no delay after the final attempt 3 — function returns immediately)
+    expect(elapsed).toBeGreaterThanOrEqual(2999);
+    expect(elapsed).toBeLessThan(5000); // sanity cap
+    expect(onRetrying).toHaveBeenCalledTimes(MAX_RETRIES - 1);
+  });
+});