CodeSampleX

Пример

express 5.1.0

Проверенный пример — npm express 5.1.0. Контракт выполнен на node 22 · linux alpine/x64 · docker и пройден: express() creates application instance with…

sha256:47b3fb4776305bf101c3204f707b7258f51bf614a0c731c3ea0f14bb68788eb0

Эта сеть предлагает одно: образец, который собирается. Она запустила его в песочнице и сохранила подписанную квитанцию. Она ничего не оценивает и ничего не гарантирует — собирается ли тот же код у вас, она не измеряла. Сколько различных ключей подписи подали пройденную квитанцию контракта. Один — только автор; больше одного — значит, кто-то ещё тоже собрал. Ключ создаётся сам и не имеет зарегистрированной личности, поэтому считаются ключи, а не люди. MIT-0

Свидетельства выполнения

Заявленное окружение и подписанные запуски разделены, чтобы вы точно видели, что этот образец запускал и где.

Основа свидетельства
Подписанный контракт пройден
Квитанции проверки
1
Ключи подписи, собравшие его
1
Заявленная среда linux 24 · ubuntu · glibc 2.39 x64 npm

Среды запусков проверки

Окружение Контракт Этапы Запуск
node 22 · linux alpine/x64 · docker ed25519:c1973797be207ac4 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · node-typescript@1		 2026-08-20

Кейс

HOW
Цель
verify pkg:npm/express@5.1.0
Пакеты
Создан
2026-08-20T14:09:02Z

Контракт

  1. express() creates application instance with routing and HTTP methods
  2. express.json() parses JSON request bodies into req.body
  3. express.urlencoded({ extended: false }) parses URL-encoded form bodies into req.body
  4. req.params and req.query extract route path parameters and query strings
  5. express.Router() mounts modular sub-application route handlers
  6. Express 5 handles async route handlers and forwards rejected promise errors to error middleware
  7. custom 4-argument error middleware handles application errors and returns error response

Файлы

  • PROMPT.md
  • csx.json
  • package-lock.json
  • package.json
  • spec.json
  • test/contract.js

Скачать артефакт с исходным кодом (tar.gz)

Исходный код

PROMPT.md
Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify pkg:npm/express@5.1.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/express@5.1.0

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.
csx.json
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package-lock.json
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  "name": "csx-sample-express",
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      "name": "csx-sample-express",
      "version": "1.0.0",
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package.json
{
  "name": "csx-sample-express",
  "version": "1.0.0",
  "private": true,
  "description": "Clean-room verification for express@5.1.0",
  "main": "test/contract.js",
  "scripts": {
    "test": "node test/contract.js"
  },
  "dependencies": {
    "express": "5.1.0"
  },
  "license": "MIT-0"
}
spec.json
{
  "schemaVersion": 1,
  "goal": "verify pkg:npm/express@5.1.0",
  "kind": "HOW",
  "packages": [
    "pkg:npm/express@5.1.0"
  ]
}
test/contract.js
const assert = require('assert');
const http = require('http');
const express = require('express');

async function runTests() {
  const app = express();

  // 1. Built-in middleware
  app.use(express.json());
  app.use(express.urlencoded({ extended: false }));

  // 2. Basic GET endpoint
  app.get('/health', (req, res) => {
    res.status(200).json({ status: 'ok', uptime: process.uptime() > 0 });
  });

  // 3. POST endpoint with JSON body and header manipulation
  app.post('/api/echo', (req, res) => {
    res.setHeader('X-Custom-Header', 'express-5');
    res.status(201).json({ received: req.body });
  });

  // 4. URL-encoded body
  app.post('/api/urlencoded', (req, res) => {
    res.status(200).json({ parsed: req.body });
  });

  // 5. Route params and query string parsing
  app.get('/api/users/:userId/items/:itemId', (req, res) => {
    res.status(200).json({
      params: req.params,
      query: req.query
    });
  });

  // 6. Router modular sub-app
  const router = express.Router();
  router.get('/ping', (req, res) => {
    res.send('pong');
  });
  router.get('/info', (req, res) => {
    res.json({ routed: true });
  });
  app.use('/sub', router);

  // 7. Express 5 native async route handler support (rejected promise -> error handler)
  app.get('/api/async-success', async (req, res) => {
    const result = await Promise.resolve({ success: true, message: 'async resolution' });
    res.json(result);
  });

  app.get('/api/async-error', async (req, res) => {
    // In Express 5, returning a rejected promise automatically invokes error-handling middleware
    throw new Error('Async error thrown in Express 5 handler');
  });

  // 8. Custom 4-argument Error handling middleware
  app.use((err, req, res, next) => {
    res.status(500).json({
      error: true,
      message: err.message
    });
  });

  // Start HTTP server on dynamic port
  const server = http.createServer(app);
  await new Promise((resolve) => server.listen(0, '127.0.0.1', resolve));
  const port = server.address().port;
  const baseUrl = `http://127.0.0.1:${port}`;

  // Helper request function
  async function request(path, options = {}) {
    const url = new URL(path, baseUrl);
    const headers = options.headers || {};
    let body = options.body;

    if (body && typeof body === 'object' && !Buffer.isBuffer(body) && !(body instanceof URLSearchParams)) {
      body = JSON.stringify(body);
      headers['Content-Type'] = 'application/json';
    }

    return new Promise((resolve, reject) => {
      const req = http.request(url, {
        method: options.method || 'GET',
        headers: headers
      }, (res) => {
        let raw = '';
        res.on('data', chunk => raw += chunk);
        res.on('end', () => {
          let parsedJson = null;
          try {
            parsedJson = JSON.parse(raw);
          } catch (_) {
            // not JSON
          }
          resolve({
            status: res.statusCode,
            headers: res.headers,
            text: raw,
            json: parsedJson
          });
        });
      });
      req.on('error', reject);
      if (body) {
        req.write(body);
      }
      req.end();
    });
  }

  // --- Test Assertions ---

  // Test 1: Health check
  const healthRes = await request('/health');
  assert.strictEqual(healthRes.status, 200, 'GET /health should return status 200');
  assert.strictEqual(healthRes.json.status, 'ok', 'Health status should be ok');

  // Test 2: JSON Body parsing and response headers
  const echoRes = await request('/api/echo', {
    method: 'POST',
    body: { name: 'express-test', count: 5 }
  });
  assert.strictEqual(echoRes.status, 201, 'POST /api/echo should return status 201');
  assert.deepStrictEqual(echoRes.json.received, { name: 'express-test', count: 5 }, 'Body should match posted JSON');
  assert.strictEqual(echoRes.headers['x-custom-header'], 'express-5', 'Custom header should be present');

  // Test 3: URL-encoded body parsing
  const formRes = await request('/api/urlencoded', {
    method: 'POST',
    headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
    body: 'key=value&framework=express5'
  });
  assert.strictEqual(formRes.status, 200, 'POST /api/urlencoded should return status 200');
  assert.deepStrictEqual(formRes.json.parsed, { key: 'value', framework: 'express5' }, 'URL-encoded body should be parsed correctly');

  // Test 4: Route parameters and query parameters
  const paramsRes = await request('/api/users/42/items/99?sort=asc&filter=active');
  assert.strictEqual(paramsRes.status, 200, 'Route params endpoint should return status 200');
  assert.strictEqual(paramsRes.json.params.userId, '42', 'params.userId should be parsed');
  assert.strictEqual(paramsRes.json.params.itemId, '99', 'params.itemId should be parsed');
  assert.strictEqual(paramsRes.json.query.sort, 'asc', 'query.sort should be parsed');
  assert.strictEqual(paramsRes.json.query.filter, 'active', 'query.filter should be parsed');

  // Test 5: express.Router modular sub-app
  const routerRes1 = await request('/sub/ping');
  assert.strictEqual(routerRes1.status, 200, 'GET /sub/ping should return status 200');
  assert.strictEqual(routerRes1.text, 'pong', 'GET /sub/ping response should be pong');

  const routerRes2 = await request('/sub/info');
  assert.strictEqual(routerRes2.status, 200, 'GET /sub/info should return status 200');
  assert.deepStrictEqual(routerRes2.json, { routed: true }, 'GET /sub/info response should match JSON');

  // Test 6: Native async route handler (Success)
  const asyncSuccessRes = await request('/api/async-success');
  assert.strictEqual(asyncSuccessRes.status, 200, 'Async success handler should return status 200');
  assert.deepStrictEqual(asyncSuccessRes.json, { success: true, message: 'async resolution' }, 'Async response body should match resolved object');

  // Test 7: Express 5 native async route handler (Error propagation to error middleware)
  const asyncErrorRes = await request('/api/async-error');
  assert.strictEqual(asyncErrorRes.status, 500, 'Async error should be caught by error handler and return status 500');
  assert.strictEqual(asyncErrorRes.json.error, true, 'Error response error field should be true');
  assert.strictEqual(asyncErrorRes.json.message, 'Async error thrown in Express 5 handler', 'Error response message should match thrown Error');

  // Close server
  await new Promise((resolve) => server.close(resolve));
  console.log('All Express 5.1.0 contract assertions passed successfully.');
}

runTests().catch((err) => {
  console.error('Contract test failed:', err);
  process.exit(1);
});

Исходный сидер

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