got 11.8.6: post

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 got.post in pkg:npm/got@11.8.6
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/got@11.8.6
Demonstrate these symbols/APIs:
  - got.post

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.

{"case":{"caseId":"case:sha256:e204fd6fa9bd0d76ca50f69895a95a1381152190bf261bd7353eb411cce29a66","contract":["got.post is a callable function on the got object","got.post returns a cancelable request promise with .json helper","got.post throws got.RequestError when mutually exclusive body options are specified","got.post throws got.RequestError when invalid body type is provided","got.post sends POST request with serialized JSON payload and parses JSON response","got.post sends application/x-www-form-urlencoded payload when form option is used","got.post sends raw string body when body option is used","got.post includes custom headers in the HTTP request","got.post throws got.HTTPError on non-2xx HTTP responses","postJson helper sends JSON payload and receives parsed response","postForm helper sends form urlencoded payload","postText helper sends raw text payload"],"goal":"verify got.post in pkg:npm/got@11.8.6","kind":"HOW","packages":["pkg:npm/got@11.8.6"],"schemaVersion":1,"symbols":["got.post"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","language":"javascript","libc":"glibc","libcVersion":"2.39","moduleSystem":"esm","os":"linux","osVersionBucket":"24","packageManager":"npm","packageManagerVersion":"10.9.8","runtime":"node","runtimeVersion":"22.23.2","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/got@11.8.6"],"schemaVersion":1,"subject":"pkg:npm/got@11.8.6","symbols":["got.post"],"verifierAdapter":"node-typescript@1"}

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{
  "name": "sample-got-post",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "license": "MIT-0",
  "scripts": {
    "test": "node test/contract.mjs"
  },
  "dependencies": {
    "got": "11.8.6"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify got.post in pkg:npm/got@11.8.6",
  "kind": "HOW",
  "packages": [
    "pkg:npm/got@11.8.6"
  ],
  "symbols": [
    "got.post"
  ]
}

import got from 'got';

/**
 * Sends an HTTP POST request with a JSON payload and expects a JSON response.
 * @param {string|URL} url Target URL or path relative to prefixUrl.
 * @param {unknown} data JSON-serializable payload.
 * @param {object} [options={}] Additional Got options.
 * @returns {import('got').CancelableRequest<import('got').Response<unknown>>}
 */
export function postJson(url, data, options = {}) {
  return got.post(url, {
    ...options,
    json: data,
    responseType: 'json'
  });
}

/**
 * Sends an HTTP POST request with form-encoded data (application/x-www-form-urlencoded).
 * @param {string|URL} url Target URL or path relative to prefixUrl.
 * @param {Record<string, unknown>} formData Key-value form fields.
 * @param {object} [options={}] Additional Got options.
 * @returns {import('got').CancelableRequest<import('got').Response<string>>}
 */
export function postForm(url, formData, options = {}) {
  return got.post(url, {
    ...options,
    form: formData
  });
}

/**
 * Sends an HTTP POST request with raw text or buffer body.
 * @param {string|URL} url Target URL or path relative to prefixUrl.
 * @param {string|Buffer} body Raw payload body.
 * @param {object} [options={}] Additional Got options.
 * @returns {import('got').CancelableRequest<import('got').Response<string>>}
 */
export function postText(url, body, options = {}) {
  return got.post(url, {
    ...options,
    body
  });
}

export { got };
export default got;

import assert from 'node:assert/strict';
import http from 'node:http';
import got, { postJson, postForm, postText } from '../src/index.mjs';

// 1. got.post is a callable function on the got object
{
  assert.equal(typeof got.post, 'function', 'got.post should be a function');
}

// 2. got.post returns a cancelable request promise with .json helper
{
  const req = got.post('http://127.0.0.1:0', { body: 'test' });
  req.catch(() => {}); // prevent unhandled rejection
  assert.equal(typeof req.then, 'function', 'return value should be thenable');
  assert.equal(typeof req.json, 'function', 'return value should have .json() method');
  assert.equal(typeof req.cancel, 'function', 'return value should have .cancel() method');
}

// 3. got.post throws got.RequestError when mutually exclusive body options are specified
{
  await assert.rejects(
    async () => {
      await got.post('http://127.0.0.1:0', {
        json: { key: 'val' },
        form: { key: 'val' }
      });
    },
    (err) => {
      assert(err instanceof got.RequestError, 'Should throw got.RequestError');
      assert.match(err.message, /mutually exclusive/i);
      return true;
    }
  );
}

// 4. got.post throws got.RequestError when invalid body type is provided
{
  await assert.rejects(
    async () => {
      await got.post('http://127.0.0.1:0', {
        body: 12345
      });
    },
    (err) => {
      assert(err instanceof got.RequestError, 'Should throw got.RequestError');
      assert.match(err.message, /must be a stream\.Readable, string or Buffer/i);
      return true;
    }
  );
}

// Set up offline local HTTP server to verify network behaviors
const recordedRequests = [];

const server = http.createServer(async (req, res) => {
  let body = '';
  for await (const chunk of req) {
    body += chunk;
  }

  recordedRequests.push({
    method: req.method,
    url: req.url,
    headers: req.headers,
    body
  });

  if (req.url === '/json') {
    res.writeHead(200, { 'Content-Type': 'application/json' });
    res.end(JSON.stringify({ received: JSON.parse(body), status: 'ok' }));
  } else if (req.url === '/form') {
    res.writeHead(200, { 'Content-Type': 'text/plain' });
    res.end(`echo: ${body}`);
  } else if (req.url === '/text') {
    res.writeHead(200, { 'Content-Type': 'text/plain' });
    res.end(`echo: ${body}`);
  } else if (req.url === '/error') {
    res.writeHead(400, { 'Content-Type': 'application/json' });
    res.end(JSON.stringify({ error: 'bad_request' }));
  } else {
    res.writeHead(404);
    res.end('Not Found');
  }
});

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}`;

try {
  // 5. got.post sends POST request with serialized JSON payload and parses JSON response
  {
    const payload = { title: 'Test Post', count: 42 };
    const response = await got.post(`${baseUrl}/json`, {
      json: payload,
      responseType: 'json'
    });

    assert.equal(response.statusCode, 200);
    assert.deepEqual(response.body, { received: payload, status: 'ok' });

    const lastReq = recordedRequests[recordedRequests.length - 1];
    assert.equal(lastReq.method, 'POST');
    assert.match(lastReq.headers['content-type'], /^application\/json/);
    assert.deepEqual(JSON.parse(lastReq.body), payload);
  }

  // 6. got.post sends application/x-www-form-urlencoded payload when form option is used
  {
    const formFields = { user: 'alice', action: 'login' };
    const response = await got.post(`${baseUrl}/form`, {
      form: formFields
    });

    assert.equal(response.statusCode, 200);
    assert.equal(response.body, 'echo: user=alice&action=login');

    const lastReq = recordedRequests[recordedRequests.length - 1];
    assert.equal(lastReq.method, 'POST');
    assert.match(lastReq.headers['content-type'], /^application\/x-www-form-urlencoded/);
  }

  // 7. got.post sends raw string body when body option is used
  {
    const rawText = 'raw payload content';
    const response = await got.post(`${baseUrl}/text`, {
      body: rawText,
      headers: {
        'content-type': 'text/plain'
      }
    });

    assert.equal(response.statusCode, 200);
    assert.equal(response.body, 'echo: raw payload content');

    const lastReq = recordedRequests[recordedRequests.length - 1];
    assert.equal(lastReq.method, 'POST');
    assert.equal(lastReq.body, rawText);
  }

  // 8. got.post includes custom headers in the HTTP request
  {
    await got.post(`${baseUrl}/text`, {
      body: 'ping',
      headers: {
        'x-custom-header': 'custom-value',
        'x-request-id': 'req-98765'
      }
    });

    const lastReq = recordedRequests[recordedRequests.length - 1];
    assert.equal(lastReq.headers['x-custom-header'], 'custom-value');
    assert.equal(lastReq.headers['x-request-id'], 'req-98765');
  }

  // 9. got.post throws got.HTTPError on non-2xx HTTP responses
  {
    await assert.rejects(
      async () => {
        await got.post(`${baseUrl}/error`, {
          json: { test: true }
        });
      },
      (err) => {
        assert(err instanceof got.HTTPError, 'Error should be an instance of got.HTTPError');
        assert.equal(err.response.statusCode, 400);
        return true;
      }
    );
  }

  // 10. postJson helper sends JSON payload and receives parsed response
  {
    const payload = { helper: 'json' };
    const response = await postJson(`${baseUrl}/json`, payload);
    assert.equal(response.statusCode, 200);
    assert.deepEqual(response.body, { received: payload, status: 'ok' });
  }

  // 11. postForm helper sends form urlencoded payload
  {
    const response = await postForm(`${baseUrl}/form`, { foo: 'bar' });
    assert.equal(response.statusCode, 200);
    assert.equal(response.body, 'echo: foo=bar');
  }

  // 12. postText helper sends raw text payload
  {
    const response = await postText(`${baseUrl}/text`, 'helper text');
    assert.equal(response.statusCode, 200);
    assert.equal(response.body, 'echo: helper text');
  }

} finally {
  server.close();
}

console.log('Contract tests passed successfully.');