feat: add race cover image extraction

backend/test/app.test.ts

@@ -2,6 +2,7 @@ import assert from "node:assert/strict";
 import { test } from "node:test";
 import request from "supertest";
 import { createApp } from "../src/app";
+import { extractRaceCoverImageFromHtml } from "../src/raceCoverImage";
 
 const app = createApp();
 
@@ -45,3 +46,124 @@ test("GET /api/races/:id returns not_found", async () => {
   assert.equal(res.body.error, "not_found");
   assert.ok(Array.isArray(res.body.details));
 });
+
+test("extractRaceCoverImageFromHtml prefers runc.run intro image", () => {
+  const html = `
+    <meta property="og:image" content="https://example.com/og.jpg">
+    <div class="run-intro__image">
+      <div class="run-intro__image-left-shadow"></div>
+      <img src="/uploads/race_landing_header_backgrounds/header.jpg" alt="">
+      <div class="run-intro__image-right-shadow"></div>
+    </div>
+  `;
+
+  assert.equal(
+    extractRaceCoverImageFromHtml(html, "https://aprilrun5km.runc.run/"),
+    "https://aprilrun5km.runc.run/uploads/race_landing_header_backgrounds/header.jpg",
+  );
+});
+
+test("extractRaceCoverImageFromHtml reads Open Graph and Twitter images", () => {
+  assert.equal(
+    extractRaceCoverImageFromHtml(
+      '<meta property="og:image" content="/cover.png">',
+      "https://example.com/race",
+    ),
+    "https://example.com/cover.png",
+  );
+  assert.equal(
+    extractRaceCoverImageFromHtml(
+      '<meta name="twitter:image" content="https://cdn.example.com/twitter.jpg">',
+      "https://example.com/race",
+    ),
+    "https://cdn.example.com/twitter.jpg",
+  );
+});
+
+test("POST /api/races stores manual coverImageUrl", async () => {
+  const coverImageUrl = "https://example.com/manual.jpg";
+  const res = await request(app)
+    .post("/api/races")
+    .send({
+      id: "2026-06-01-manual-cover",
+      date: "2026-06-01",
+      title: "Manual Cover",
+      distanceKm: 10,
+      officialUrl: "https://example.com/race",
+      coverImageUrl,
+    })
+    .expect(201);
+
+  assert.equal(res.body.coverImageUrl, coverImageUrl);
+});
+
+test("POST /api/races auto extracts coverImageUrl from officialUrl", async () => {
+  const originalFetch = globalThis.fetch;
+  globalThis.fetch = async () =>
+    new Response('<meta property="og:image" content="/auto.jpg">', {
+      status: 200,
+      headers: { "content-type": "text/html" },
+    });
+
+  try {
+    const res = await request(app)
+      .post("/api/races")
+      .send({
+        id: "2026-06-02-auto-cover",
+        date: "2026-06-02",
+        title: "Auto Cover",
+        distanceKm: 21.1,
+        officialUrl: "https://example.com/race",
+      })
+      .expect(201);
+
+    assert.equal(res.body.coverImageUrl, "https://example.com/auto.jpg");
+  } finally {
+    globalThis.fetch = originalFetch;
+  }
+});
+
+test("POST /api/races succeeds when cover extraction fails", async () => {
+  const originalFetch = globalThis.fetch;
+  globalThis.fetch = async () => {
+    throw new Error("network down");
+  };
+
+  try {
+    const res = await request(app)
+      .post("/api/races")
+      .send({
+        id: "2026-06-03-cover-fail",
+        date: "2026-06-03",
+        title: "Cover Fail",
+        distanceKm: 5,
+        officialUrl: "https://example.com/race",
+      })
+      .expect(201);
+
+    assert.equal(res.body.coverImageUrl, null);
+  } finally {
+    globalThis.fetch = originalFetch;
+  }
+});
+
+test("PATCH /api/races/:id updates coverImageUrl explicitly", async () => {
+  const id = "2026-06-04-patch-cover";
+  await request(app)
+    .post("/api/races")
+    .send({
+      id,
+      date: "2026-06-04",
+      title: "Patch Cover",
+      distanceKm: 10,
+    })
+    .expect(201);
+
+  const coverImageUrl = "https://example.com/patched.jpg";
+  const res = await request(app)
+    .patch(`/api/races/${id}`)
+    .send({ coverImageUrl })
+    .expect(200);
+
+  assert.equal(res.body.coverImageUrl, coverImageUrl);
+});