emrgilhzp: Proxy the home feed with cursor paging

tests/feed-route.test.ts

@@ -0,0 +1,40 @@
+import { describe, expect, it, vi } from "vitest";
+import { NextRequest } from "next/server";
+import { GET } from "@/app/api/feed/route";
+import { createSession } from "@/lib/session-store";
+
+describe("GET /api/feed", () => {
+  it("no cookie -> 401 sign_in", async () => {
+    const res = await GET(new NextRequest("http://localhost/api/feed"));
+    expect(res.status).toBe(401);
+    expect(await res.json()).toEqual({ error: "sign_in" });
+  });
+
+  it("signed in: page then next page with cursor; limit capped at 50", async () => {
+    const sid = createSession({
+      profileAccessToken: "p", profileAccessTokenExpiresAt: null, profileRefreshToken: "r",
+      feedAccessToken: "T", feedAccessTokenExpiresAt: null,
+      person: { userId: "u", name: "A", email: "a@b.co", pictureUrl: null }, createdAt: Date.now(),
+    });
+    const urls: string[] = [];
+    const orig = globalThis.fetch;
+    globalThis.fetch = vi.fn(async (url: string) => {
+      urls.push(String(url));
+      const next = urls.length === 1 ? "C1" : null;
+      return new Response(JSON.stringify({ data: [{ n: urls.length }], metadata: { nextCursor: next } }), { status: 200 });
+    }) as unknown as typeof fetch;
+    try {
+      const h = { cookie: `mfb_session=${sid}` };
+      const r1 = await GET(new NextRequest("http://localhost/api/feed", { headers: h }));
+      expect(await r1.json()).toEqual({ items: [{ n: 1 }], nextCursor: "C1" });
+      const r2 = await GET(new NextRequest("http://localhost/api/feed?cursor=C1&limit=500", { headers: h }));
+      expect(await r2.json()).toEqual({ items: [{ n: 2 }], nextCursor: null });
+      expect(new URL(urls[0]).searchParams.has("cursor")).toBe(false);
+      const u2 = new URL(urls[1]);
+      expect(u2.searchParams.get("cursor")).toBe("C1");
+      expect(u2.searchParams.get("limit")).toBe("50");
+    } finally {
+      globalThis.fetch = orig;
+    }
+  });
+});

tests/feed.test.ts

@@ -0,0 +1,72 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+import { clampLimit, getHomeFeedPage } from "@/lib/feed";
+import { createSession } from "@/lib/session-store";
+
+const json = (body: unknown, status = 200) =>
+  new Response(JSON.stringify(body), { status, headers: { "content-type": "application/json" } });
+
+let sid: string;
+beforeEach(() => {
+  sid = createSession({
+    profileAccessToken: "p",
+    profileAccessTokenExpiresAt: null,
+    profileRefreshToken: "r",
+    feedAccessToken: "FEEDTOK",
+    feedAccessTokenExpiresAt: null,
+    person: { userId: "u", name: "Ann", email: "a@b.co", pictureUrl: null },
+    createdAt: Date.now(),
+  });
+});
+
+describe("getHomeFeedPage", () => {
+  it("no session is sign_in and nothing is fetched", async () => {
+    const f = vi.fn();
+    expect(await getHomeFeedPage(undefined, null, 20, { fetchImpl: f as unknown as typeof fetch }))
+      .toEqual({ ok: false, status: 401, error: "sign_in" });
+    expect(f).not.toHaveBeenCalled();
+  });
+
+  it("first page: items + nextCursor, no cursor upstream, bearer token, home path", async () => {
+    const f = vi.fn(async () => json({ data: [{ id: 1 }], metadata: { nextCursor: "C1" } }));
+    const r = await getHomeFeedPage(sid, null, 20, { fetchImpl: f as unknown as typeof fetch });
+    expect(r).toEqual({ ok: true, items: [{ id: 1 }], nextCursor: "C1" });
+    const [url, init] = f.mock.calls[0] as unknown as [string, RequestInit];
+    const u = new URL(url);
+    expect(u.pathname).toBe("/api/v1/feeds/home/items");
+    expect(u.searchParams.get("limit")).toBe("20");
+    expect(u.searchParams.has("cursor")).toBe(false);
+    expect((init.headers as Record<string, string>).Authorization).toBe("Bearer FEEDTOK");
+  });
+
+  it("forwards the cursor on a later page; null nextCursor at the end", async () => {
+    const f = vi.fn(async () => json({ data: [], metadata: { nextCursor: null } }));
+    const r = await getHomeFeedPage(sid, "X", 20, { fetchImpl: f as unknown as typeof fetch });
+    expect(r).toEqual({ ok: true, items: [], nextCursor: null });
+    const u = new URL((f.mock.calls[0] as unknown as [string])[0]);
+    expect(u.searchParams.get("cursor")).toBe("X");
+  });
+
+  it("feed 401 twice is sign_in", async () => {
+    const f = vi.fn(async (url: string) =>
+      String(url).includes("/feeds/home/items") ? json({}, 401) : json({}, 500),
+    );
+    const r = await getHomeFeedPage(sid, null, 20, { fetchImpl: f as unknown as typeof fetch });
+    expect(r).toEqual({ ok: false, status: 401, error: "sign_in" });
+  });
+
+  it("upstream 500 is feed_unavailable", async () => {
+    const f = vi.fn(async () => json({}, 500));
+    const r = await getHomeFeedPage(sid, null, 20, { fetchImpl: f as unknown as typeof fetch });
+    expect(r).toEqual({ ok: false, status: 502, error: "feed_unavailable" });
+  });
+});
+
+describe("clampLimit", () => {
+  it("defaults to 20, caps at 50", () => {
+    expect(clampLimit(null)).toBe(20);
+    expect(clampLimit("abc")).toBe(20);
+    expect(clampLimit("999")).toBe(50);
+    expect(clampLimit("10")).toBe(10);
+    expect(clampLimit("0")).toBe(20);
+  });
+});