feat: Add user role retrieval, enhance recommended course filtering and detail, and introduce new k6 load tests.

Backend/tests/k6/enroll-load-test.js

@@ -0,0 +1,160 @@
+// Backend/tests/k6/enroll-load-test.js
+//
+// จำลองนักเรียนหลายคน login แล้ว enroll คอร์สพร้อมกัน
+//
+// Flow:
+//   1. Login
+//   2. Enroll คอร์ส
+//   3. ตรวจสอบ enrolled courses
+//
+// Usage:
+//   k6 run -e APP_URL=http://192.168.1.137:4000 -e COURSE_ID=1 tests/k6/enroll-load-test.js
+
+import http from 'k6/http';
+import { check, sleep, group } from 'k6';
+import { Rate, Trend, Counter } from 'k6/metrics';
+import { SharedArray } from 'k6/data';
+
+// ─── Custom Metrics ───────────────────────────────────────────────────────────
+const errorRate    = new Rate('errors');
+const loginTime    = new Trend('login_duration', true);
+const enrollTime   = new Trend('enroll_duration', true);
+const enrolledCount = new Counter('successful_enrollments');
+
+// ─── Load student credentials ─────────────────────────────────────────────────
+const students = new SharedArray('students', function () {
+  return JSON.parse(open('./test-credentials.json')).students;
+});
+
+// ─── Config ───────────────────────────────────────────────────────────────────
+const BASE_URL  = __ENV.APP_URL   || 'http://192.168.1.137:4000';
+const COURSE_ID = __ENV.COURSE_ID || '1';
+
+// ─── Test Options ─────────────────────────────────────────────────────────────
+export const options = {
+  stages: [
+    { duration: '20s', target: 10 },  // Ramp up
+    { duration: '1m',  target: 30 },  // Increase
+    { duration: '30s', target: 50 },  // Peak: 50 คน enroll พร้อมกัน
+    { duration: '30s', target: 0 },   // Ramp down
+  ],
+  thresholds: {
+    'login_duration':  ['p(95)<2000'],  // Login < 2s
+    'enroll_duration': ['p(95)<1000'],  // Enroll < 1s
+    'errors':          ['rate<0.05'],
+    'http_req_failed': ['rate<0.05'],
+  },
+};
+
+// ─── Helper ───────────────────────────────────────────────────────────────────
+function jsonHeaders(token) {
+  const h = { 'Content-Type': 'application/json' };
+  if (token) h['Authorization'] = `Bearer ${token}`;
+  return h;
+}
+
+// ─── Main ─────────────────────────────────────────────────────────────────────
+export default function () {
+  const student = students[__VU % students.length];
+  let token = null;
+
+  // ── Step 1: Login ──────────────────────────────────────────────────────────
+  group('1. Login', () => {
+    const res = http.post(
+      `${BASE_URL}/api/auth/login`,
+      JSON.stringify({ email: student.email, password: student.password }),
+      { headers: jsonHeaders(null) }
+    );
+
+    loginTime.add(res.timings.duration);
+    errorRate.add(res.status !== 200);
+
+    check(res, {
+      'login: status 200': (r) => r.status === 200,
+      'login: has token':  (r) => { try { return !!r.json('data.token'); } catch { return false; } },
+    });
+
+    if (res.status === 200) {
+      try { token = res.json('data.token'); } catch {}
+    }
+  });
+
+  if (!token) {
+    console.warn(`[VU ${__VU}] Login failed for ${student.email} — skipping`);
+    sleep(1);
+    return;
+  }
+
+  sleep(0.5);
+
+  // ── Step 2: Enroll ─────────────────────────────────────────────────────────
+  group('2. Enroll Course', () => {
+    const res = http.post(
+      `${BASE_URL}/api/students/courses/${COURSE_ID}/enroll`,
+      null,
+      { headers: jsonHeaders(token) }
+    );
+
+    enrollTime.add(res.timings.duration);
+
+    // 200 = enrolled, 409 = already enrolled (ถือว่าโอเค)
+    const ok = res.status === 200 || res.status === 409;
+    errorRate.add(!ok);
+
+    if (res.status === 200) enrolledCount.add(1);
+
+    check(res, {
+      'enroll: 200 or 409':    (r) => r.status === 200 || r.status === 409,
+      'enroll: fast response': (r) => r.timings.duration < 1000,
+    });
+  });
+
+  sleep(0.5);
+
+  // ── Step 3: Verify — ดึงรายการคอร์สที่ลงทะเบียน ─────────────────────────
+  group('3. Get Enrolled Courses', () => {
+    const res = http.get(
+      `${BASE_URL}/api/students/courses`,
+      { headers: jsonHeaders(token) }
+    );
+
+    errorRate.add(res.status !== 200);
+
+    check(res, {
+      'enrolled courses: status 200': (r) => r.status === 200,
+    });
+  });
+
+  sleep(1);
+}
+
+// ─── Summary ──────────────────────────────────────────────────────────────────
+export function handleSummary(data) {
+  const m   = data.metrics;
+  const avg = (k) => m[k]?.values?.avg?.toFixed(0) ?? 'N/A';
+  const p95 = (k) => m[k]?.values?.['p(95)']?.toFixed(0) ?? 'N/A';
+  const rate = (k) => ((m[k]?.values?.rate ?? 0) * 100).toFixed(2);
+  const cnt  = (k) => m[k]?.values?.count ?? 0;
+
+  return {
+    stdout: `
+╔══════════════════════════════════════════════════════════╗
+║              Course Enroll — Load Test                   ║
+╠══════════════════════════════════════════════════════════╣
+║  Course ID  : ${String(COURSE_ID).padEnd(43)}║
+╠══════════════════════════════════════════════════════════╣
+║  RESPONSE TIMES (avg / p95)                              ║
+║  Login          : ${avg('login_duration')}ms / ${p95('login_duration')}ms
+║  Enroll         : ${avg('enroll_duration')}ms / ${p95('enroll_duration')}ms
+╠══════════════════════════════════════════════════════════╣
+║  COUNTS                                                  ║
+║  Total Requests     : ${String(cnt('http_reqs')).padEnd(33)}║
+║  New Enrollments    : ${String(cnt('successful_enrollments')).padEnd(33)}║
+╠══════════════════════════════════════════════════════════╣
+║  ERROR RATES                                             ║
+║  HTTP Failed    : ${(rate('http_req_failed') + '%').padEnd(39)}║
+║  Custom Errors  : ${(rate('errors') + '%').padEnd(39)}║
+╚══════════════════════════════════════════════════════════╝
+`,
+  };
+}