fix(api): parse Retry-After HTTP-date format and remove dead fallback code (#572)

src/lib/api.test.ts

@@ -71,3 +71,58 @@ describe("fetchIndexableReputationHandles", () => {
     expect(result.data).toEqual(["mock-handle"]);
   });
 });
+
+describe("parseRetryAfter", () => {
+  it("parses integer seconds correctly", () => {
+    const { parseRetryAfter } = require("./api");
+    expect(parseRetryAfter("120")).toBe(120);
+    expect(parseRetryAfter("0")).toBe(0);
+    expect(parseRetryAfter("  45  ")).toBe(45);
+    expect(parseRetryAfter("-10")).toBeUndefined();
+    expect(parseRetryAfter("invalid")).toBeUndefined();
+  });
+
+  it("parses HTTP-date headers into remaining seconds", () => {
+    const { parseRetryAfter } = require("./api");
+    const futureDate = new Date(Date.now() + 60_000).toUTCString();
+    const seconds = parseRetryAfter(futureDate);
+    expect(seconds).toBeGreaterThanOrEqual(58);
+    expect(seconds).toBeLessThanOrEqual(61);
+  });
+});
+
+describe("apiRequest rate limiting (429)", () => {
+  const originalFetch = global.fetch;
+
+  afterAll(() => {
+    global.fetch = originalFetch;
+  });
+
+  it("formats 429 error message correctly with integer Retry-After", async () => {
+    const { apiRequest, ApiRequestError } = require("./api");
+    global.fetch = jest.fn().mockResolvedValue({
+      status: 429,
+      ok: false,
+      headers: new Headers({ "Retry-After": "30" }),
+    }) as unknown as typeof fetch;
+
+    await expect(apiRequest("/test-endpoint")).rejects.toThrow(ApiRequestError);
+    await expect(apiRequest("/test-endpoint")).rejects.toThrow(
+      "You're doing that too fast. Please wait 30 seconds before trying again.",
+    );
+  });
+
+  it("formats 429 error message correctly without Retry-After header", async () => {
+    const { apiRequest } = require("./api");
+    global.fetch = jest.fn().mockResolvedValue({
+      status: 429,
+      ok: false,
+      headers: new Headers(),
+    }) as unknown as typeof fetch;
+
+    await expect(apiRequest("/test-endpoint-no-header")).rejects.toThrow(
+      "You're doing that too fast.",
+    );
+  });
+});
+

src/lib/api.ts

@@ -95,6 +95,22 @@ async function dedupedFetch<T>(
   return promise;
 }
 
+export function parseRetryAfter(header: string): number | undefined {
+  const trimmed = header.trim();
+  if (/^\d+$/.test(trimmed)) {
+    const sec = parseInt(trimmed, 10);
+    return Number.isFinite(sec) && sec >= 0 ? sec : undefined;
+  }
+  if (!trimmed.includes("GMT") && !trimmed.includes(",")) {
+    return undefined;
+  }
+  const dateMs = Date.parse(trimmed);
+  if (!Number.isNaN(dateMs)) {
+    return Math.max(0, Math.ceil((dateMs - Date.now()) / 1000));
+  }
+  return undefined;
+}
+
 /**
  * Client-side call that attaches the signed-in user's JWT (if any) and
  * surfaces backend error bodies instead of silently falling back — used for
@@ -132,14 +148,14 @@ export async function apiRequest<T>(
     // --- Rate-limit handling (#44) ---
     if (res.status === 429) {
       const retryAfter = res.headers.get("Retry-After");
-      const seconds = retryAfter ? parseInt(retryAfter, 10) : NaN;
-      const waitMsg = Number.isFinite(seconds)
+      const seconds = retryAfter ? parseRetryAfter(retryAfter) : undefined;
+      const waitMsg = seconds !== undefined
         ? ` Please wait ${seconds} second${seconds === 1 ? "" : "s"} before trying again.`
         : "";
       throw new ApiRequestError(
-        `You're doing that too fast.${waitMsg}` || `Rate limited. Please try again later.`,
+        `You're doing that too fast.${waitMsg}`,
         429,
-        Number.isFinite(seconds) ? seconds : undefined,
+        seconds,
       );
     }