minipass-fetch 4.0.1: fetch

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 fetch in pkg:npm/minipass-fetch@4.0.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/minipass-fetch@4.0.1
Demonstrate these symbols/APIs:
  - fetch

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:sha256:65237b2dc257df0b4f287fd11a27f6b0ff1246f61e5330cc5dcad5f6b392b665","contract":["fetch resolves plain and base64 data: URIs into Response instances with decoded body and Content-Type header, and rejects malformed data: URIs with FetchError (type 'system')","fetch.isRedirect returns true for HTTP redirect status codes (301, 302, 303, 307, 308) and false for non-redirect status codes","fetch sends POST requests with custom headers and body, automatically decompresses gzip-encoded responses by default, and returns raw compressed bytes when compress: false","fetch follows 302 redirects by converting POST to GET, preserves 302 with resolved Location on redirect: 'manual', rejects with FetchError (type 'no-redirect') on redirect: 'error', and enforces the follow redirect limit (type 'max-redirect')","fetch rejects with AbortError when passed an aborted AbortSignal"],"goal":"verify fetch in pkg:npm/minipass-fetch@4.0.1","kind":"HOW","packages":["pkg:npm/minipass-fetch@4.0.1"],"schemaVersion":1,"symbols":["fetch"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","executionContext":"node","libc":"glibc","libcVersion":"2.39","moduleSystem":"esm","os":"linux","osVersionBucket":"24","packageManager":"npm","runtime":"node","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/minipass-fetch@4.0.1"],"schemaVersion":1,"subject":"pkg:npm/minipass-fetch@4.0.1","symbols":["fetch"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-minipass-fetch",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-minipass-fetch",
      "version": "1.0.0",
      "dependencies": {
        "minipass-fetch": "4.0.1"
      }
    },
    "node_modules/encoding": {
      "version": "0.1.13",
      "resolved": "https://registry.npmjs.org/encoding/-/encoding-0.1.13.tgz",
      "integrity": "sha512-ETBauow1T35Y/WZMkio9jiM0Z5xjHHmJ4XmjZOq1l/dXz3lr2sRn87nJy20RupqSh1F2m3HHPSp8ShIPQJrJ3A==",
      "license": "MIT",
      "optional": true,
      "dependencies": {
        "iconv-lite": "^0.6.2"
      }
    },
    "node_modules/iconv-lite": {
      "version": "0.6.3",
      "resolved": "https://registry.npmjs.org/iconv-lite/-/iconv-lite-0.6.3.tgz",
      "integrity": "sha512-4fCk79wshMdzMp2rH06qWrJE4iolqLhCUH+OiuIgU++RB0+94NlDL81atO7GX55uUKueo0txHNtvEyI6D7WdMw==",
      "license": "MIT",
      "optional": true,
      "dependencies": {
        "safer-buffer": ">= 2.1.2 < 3.0.0"
      },
      "engines": {
        "node": ">=0.10.0"
      }
    },
    "node_modules/minipass": {
      "version": "7.1.3",
      "resolved": "https://registry.npmjs.org/minipass/-/minipass-7.1.3.tgz",
      "integrity": "sha512-tEBHqDnIoM/1rXME1zgka9g6Q2lcoCkxHLuc7ODJ5BxbP5d4c2Z5cGgtXAku59200Cx7diuHTOYfSBD8n6mm8A==",
      "license": "BlueOak-1.0.0",
      "engines": {
        "node": ">=16 || 14 >=14.17"
      }
    },
    "node_modules/minipass-fetch": {
      "version": "4.0.1",
      "resolved": "https://registry.npmjs.org/minipass-fetch/-/minipass-fetch-4.0.1.tgz",
      "integrity": "sha512-j7U11C5HXigVuutxebFadoYBbd7VSdZWggSe64NVdvWNBqGAiXPL2QVCehjmw7lY1oF9gOllYbORh+hiNgfPgQ==",
      "license": "MIT",
      "dependencies": {
        "minipass": "^7.0.3",
        "minipass-sized": "^1.0.3",
        "minizlib": "^3.0.1"
      },
      "engines": {
        "node": "^18.17.0 || >=20.5.0"
      },
      "optionalDependencies": {
        "encoding": "^0.1.13"
      }
    },
    "node_modules/minipass-sized": {
      "version": "1.0.3",
      "resolved": "https://registry.npmjs.org/minipass-sized/-/minipass-sized-1.0.3.tgz",
      "integrity": "sha512-MbkQQ2CTiBMlA2Dm/5cY+9SWFEN8pzzOXi6rlM5Xxq0Yqbda5ZQy9sU75a673FE9ZK0Zsbr6Y5iP6u9nktfg2g==",
      "license": "ISC",
      "dependencies": {
        "minipass": "^3.0.0"
      },
      "engines": {
        "node": ">=8"
      }
    },
    "node_modules/minipass-sized/node_modules/minipass": {
      "version": "3.3.6",
      "resolved": "https://registry.npmjs.org/minipass/-/minipass-3.3.6.tgz",
      "integrity": "sha512-DxiNidxSEK+tHG6zOIklvNOwm3hvCrbUrdtzY74U6HKTJxvIDfOUL5W5P2Ghd3DTkhhKPYGqeNUIh5qcM4YBfw==",
      "license": "ISC",
      "dependencies": {
        "yallist": "^4.0.0"
      },
      "engines": {
        "node": ">=8"
      }
    },
    "node_modules/minizlib": {
      "version": "3.1.0",
      "resolved": "https://registry.npmjs.org/minizlib/-/minizlib-3.1.0.tgz",
      "integrity": "sha512-KZxYo1BUkWD2TVFLr0MQoM8vUUigWD3LlD83a/75BqC+4qE0Hb1Vo5v1FgcfaNXvfXzr+5EhQ6ing/CaBijTlw==",
      "license": "MIT",
      "dependencies": {
        "minipass": "^7.1.2"
      },
      "engines": {
        "node": ">= 18"
      }
    },
    "node_modules/safer-buffer": {
      "version": "2.1.2",
      "resolved": "https://registry.npmjs.org/safer-buffer/-/safer-buffer-2.1.2.tgz",
      "integrity": "sha512-YZo3K82SD7Riyi0E1EQPojLz7kpepnSQI9IyPbHHg1XXXevb5dJI7tpyN2ADxGcQbHG7vcyRHk0cbwqcQriUtg==",
      "license": "MIT",
      "optional": true
    },
    "node_modules/yallist": {
      "version": "4.0.0",
      "resolved": "https://registry.npmjs.org/yallist/-/yallist-4.0.0.tgz",
      "integrity": "sha512-3wdGidZyq5PB084XLES5TpOSRA3wjXAlIWMhum2kRcv/41Sn2emQ0dycQW4uZXLejwKvg6EsvbdlVL+FYEct7A==",
      "license": "ISC"
    }
  }
}

{
  "name": "sample-minipass-fetch",
  "version": "1.0.0",
  "private": true,
  "type": "module",
  "scripts": {
    "test": "node test/contract.mjs"
  },
  "dependencies": {
    "minipass-fetch": "4.0.1"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify fetch in pkg:npm/minipass-fetch@4.0.1",
  "kind": "HOW",
  "packages": [
    "pkg:npm/minipass-fetch@4.0.1"
  ],
  "symbols": [
    "fetch"
  ]
}

import assert from 'node:assert/strict'
import http from 'node:http'
import zlib from 'node:zlib'
import fetch from 'minipass-fetch'

// 1. Verify data: URI resolution (plain text, base64, and invalid data: URI)
{
  const plainRes = await fetch('data:text/plain;charset=utf-8,Hello%20World')
  assert.equal(plainRes.status, 200)
  assert.equal(plainRes.headers.get('content-type'), 'text/plain;charset=utf-8')
  assert.equal(await plainRes.text(), 'Hello World')

  const payload = JSON.stringify({ ok: true, count: 42 })
  const b64 = Buffer.from(payload, 'utf8').toString('base64')
  const b64Res = await fetch(`data:application/json;base64,${b64}`)
  assert.equal(b64Res.headers.get('content-type'), 'application/json')
  assert.deepEqual(await b64Res.json(), { ok: true, count: 42 })

  await assert.rejects(
    () => fetch('data:text/plain-missing-comma'),
    err => err instanceof fetch.FetchError && err.type === 'system'
  )
}

// 2. Verify fetch.isRedirect helper
{
  for (const code of [301, 302, 303, 307, 308]) {
    assert.equal(fetch.isRedirect(code), true)
  }
  for (const code of [200, 204, 300, 304, 400, 500]) {
    assert.equal(fetch.isRedirect(code), false)
  }
}

// 3. Verify HTTP requests, gzip decompression, redirects, and abort handling via local server
const server = http.createServer((req, res) => {
  if (req.url === '/echo') {
    const chunks = []
    req.on('data', c => chunks.push(c))
    req.on('end', () => {
      const body = Buffer.concat(chunks).toString('utf8')
      res.writeHead(200, { 'Content-Type': 'application/json' })
      res.end(JSON.stringify({
        method: req.method,
        customHeader: req.headers['x-test-header'] || null,
        body,
      }))
    })
    return
  }

  if (req.url === '/gzip') {
    const compressed = zlib.gzipSync(Buffer.from('compressed-payload', 'utf8'))
    res.writeHead(200, {
      'Content-Type': 'text/plain',
      'Content-Encoding': 'gzip',
    })
    res.end(compressed)
    return
  }

  if (req.url === '/redirect-302') {
    res.writeHead(302, { Location: '/echo' })
    res.end()
    return
  }

  if (req.url === '/redirect-loop') {
    res.writeHead(302, { Location: '/redirect-loop' })
    res.end()
    return
  }

  res.writeHead(404)
  res.end('not found')
})

await new Promise(resolve => server.listen(0, '127.0.0.1', resolve))
const { port } = server.address()
const baseUrl = `http://localhost:${port}`

try {
  // POST request with custom headers and JSON response
  const postRes = await fetch(`${baseUrl}/echo`, {
    method: 'POST',
    headers: { 'x-test-header': 'verified' },
    body: 'hello-post',
  })
  assert.equal(postRes.status, 200)
  assert.deepEqual(await postRes.json(), {
    method: 'POST',
    customHeader: 'verified',
    body: 'hello-post',
  })

  // Automatic gzip decompression vs compress: false
  const gzipDecoded = await fetch(`${baseUrl}/gzip`)
  assert.equal(await gzipDecoded.text(), 'compressed-payload')

  const gzipRaw = await fetch(`${baseUrl}/gzip`, { compress: false })
  const rawBuf = await gzipRaw.buffer()
  assert.equal(zlib.gunzipSync(rawBuf).toString('utf8'), 'compressed-payload')

  // Redirect handling: follow (POST -> GET on 302), manual, error, and follow limit
  const followed = await fetch(`${baseUrl}/redirect-302`, {
    method: 'POST',
    body: 'dropped-on-302',
  })
  assert.equal(followed.status, 200)
  assert.deepEqual(await followed.json(), {
    method: 'GET',
    customHeader: null,
    body: '',
  })

  const manual = await fetch(`${baseUrl}/redirect-302`, { redirect: 'manual' })
  assert.equal(manual.status, 302)
  assert.equal(manual.headers.get('location'), `${baseUrl}/echo`)

  await assert.rejects(
    () => fetch(`${baseUrl}/redirect-302`, { redirect: 'error' }),
    err => err instanceof fetch.FetchError && err.type === 'no-redirect'
  )

  await assert.rejects(
    () => fetch(`${baseUrl}/redirect-loop`, { follow: 2 }),
    err => err instanceof fetch.FetchError && err.type === 'max-redirect'
  )

  // AbortSignal cancellation
  const ac = new AbortController()
  ac.abort()
  await assert.rejects(
    () => fetch(`${baseUrl}/echo`, { signal: ac.signal }),
    err => err instanceof fetch.AbortError && err.name === 'AbortError'
  )
} finally {
  await new Promise(resolve => server.close(resolve))
}