release-post.js

#!/usr/bin/env node

/**
 * What's this?? It will help you create release blog
 * posts so you won't have to do the tedious work
 * of stitching together data from changelog, shasums etc,
 * but get a more or less complete release blog ready to go.
 *
 * Usage: $ node release-post.js [version]
 *
 * If the version argument is omitted, the latest version number
 * will be picked from https://nodejs.org/dist/index.json.
 *
 * It'll create a file with the blog post content
 * into ../locale/en/blog/release/vX.md ready for you to commit
 * or possibly edit by hand before committing.
 *
 * Happy releasing!
 */

'use strict'

const fs = require('fs')
const path = require('path')
const Handlebars = require('handlebars')
const fetch = require('node-fetch')

const downloads = require('./helpers/downloads')

function sendRequest (opts) {
  const options = {
    headers: { 'User-Agent': 'nodejs.org release blog post script' },
    ...opts
  }

  return fetch(options.url, options).then(resp => {
    if (resp.status !== 200) {
      throw new Error(`Invalid status code (!= 200) while retrieving ${options.url}: ${resp.status}`)
    }
    return options.json ? resp.json() : resp.text()
  })
}

function explicitVersion (version) {
  return version
    ? Promise.resolve(version)
    : Promise.reject(new Error('Invalid "version" argument'))
}

function findLatestVersion () {
  return sendRequest({ url: 'https://nodejs.org/dist/index.json', json: true })
    .then((versions) => versions[0].version.substr(1))
}

function fetchDocs (version) {
  return Promise.all([
    fetchChangelogBody(version),
    fetchAuthor(version),
    fetchVersionPolicy(version),
    fetchShasums(version),
    verifyDownloads(version)
  ]).then((results) => {
    const [changelog, author, versionPolicy, shasums, files] = results
    return {
      version,
      changelog,
      author,
      versionPolicy,
      shasums,
      files
    }
  })
}

function fetchAuthor (version) {
  return fetchChangelog(version)
    .then((section) => findAuthorLogin(version, section))
    .then((author) => sendRequest({
      url: `https://api.github.com/users/${author}`,
      json: true
    }))
    .then((githubRes) => githubRes.name)
}

function fetchChangelog (version) {
  const parts = version.split('.')
  const releaseLine = parts[0] === '0'
    ? parts.slice(0, 2).join('')
    : parts[0]

  return sendRequest({
    url: `https://raw.githubusercontent.com/nodejs/node/master/doc/changelogs/CHANGELOG_V${releaseLine}.md`
  }).then((data) => {
    // matches a complete release section
    const rxSection = new RegExp(`<a id="${version}"></a>\\n([\\s\\S]+?)(?:\\n<a id="|$)`)
    const matches = rxSection.exec(data)
    return matches
      ? matches[1].trim()
      : Promise.reject(new Error(`Couldn't find matching changelog for ${version}`))
  })
}

function fetchChangelogBody (version) {
  return fetchChangelog(version).then((section) => {
    const rxSectionBody = /(### Notable [\s\S]*)/

    // Make sure that all the console has been replaced
    // by "```shell-session" for metalsmith-prism's check to pass
    const rxSectionConsole = /```console/igm
    const matches = rxSectionBody.exec(section)
    return matches
      ? matches[1].trim().replace(rxSectionConsole, '```shell-session')
      : Promise.reject(new Error(`Could not find changelog body of ${version} release`))
  })
}

function fetchVersionPolicy (version) {
  return fetchChangelog(version).then((section) => {
    // matches the policy for a given version (Stable, LTS etc) in the changelog
    // ## 2015-10-07, Version 4.2.0 'Argon' (LTS), @jasnell
    // ## 2015-12-04, Version 0.12.9 (LTS), @rvagg
    const rxPolicy = /^## ?\d{4}-\d{2}-\d{2}, Version [^(].*\(([^)]+)\)/
    const matches = rxPolicy.exec(section)
    return matches
      ? matches[1]
      : Promise.reject(new Error(`Could not find version policy of ${version} in its changelog`))
  })
}

function fetchShasums (version) {
  return sendRequest({ url: `https://nodejs.org/dist/v${version}/SHASUMS256.txt.asc` })
    .then(null, () => '[INSERT SHASUMS HERE]')
}

function verifyDownloads (version) {
  const allDownloads = downloads(version)
  const reqs = allDownloads.map(urlOrComingSoon)
  return Promise.all(reqs)
}

function findAuthorLogin (version, section) {
  // looking for the @author part of the release header, eg:
  // ## 2016-03-08, Version 5.8.0 (Stable). @Fishrock123
  // ## 2015-10-13, Version 4.2.1 'Argon' (LTS), @jasnell
  // ## 2015-09-08, Version 4.0.0 (Stable), @rvagg
  const rxReleaseAuthor = /^## .*? \([^)]+\)[,.] @(\S+)/
  const matches = rxReleaseAuthor.exec(section)
  return matches
    ? matches[1]
    : Promise.reject(new Error(`Couldn't find @author of ${version} release :(`))
}

function urlOrComingSoon (binary) {
  return sendRequest({ url: binary.url, method: 'HEAD' }).then(
    () => `${binary.title}: ${binary.url}`,
    () => `${binary.title}: *Coming soon*`
  )
}

function renderPost (results) {
  const templateStr = fs.readFileSync(path.resolve(__dirname, 'release.hbs')).toString('utf8')
  const template = Handlebars.compile(templateStr, { noEscape: true })
  const view = Object.assign({
    date: new Date().toISOString(),
    versionSlug: slugify(results.version)
  }, results)

  return Object.assign({
    content: template(view)
  }, results)
}

function writeToFile (results) {
  const filepath = path.resolve(__dirname, '..', 'locale', 'en', 'blog', 'release', `v${results.version}.md`)

  return new Promise((resolve, reject) => {
    fs.access(filepath, fs.F_OK, (err) => {
      if (!err && process.argv[3] !== '--force') {
        return reject(new Error(`Release post for ${results.version} already exists!`))
      }

      fs.writeFile(filepath, results.content, (err1) => {
        if (err1) {
          return reject(new Error(`Failed to write Release post: Reason: ${err1.message}`))
        }

        resolve(filepath)
      })
    })
  })
}

function slugify (str) {
  return str.replace(/\./g, '-')
}

exports.explicitVersion = explicitVersion
exports.fetchShasums = fetchShasums
exports.writeToFile = writeToFile
exports.findLatestVersion = findLatestVersion
exports.verifyDownloads = verifyDownloads
exports.fetchChangelog = fetchChangelog
exports.fetchChangelogBody = fetchChangelogBody
exports.fetchAuthor = fetchAuthor
exports.fetchVersionPolicy = fetchVersionPolicy

// when script is executed directly,
// not required by another module, e.g:
// $ node scripts/release-post.js
if (require.main === module) {
  explicitVersion(process.argv[2])
    .then(null, findLatestVersion)
    .then(fetchDocs)
    .then(renderPost)
    .then(writeToFile)
    .then((filepath) => {
      console.log('Release post created:', filepath)
    }, (err) => {
      console.error('Some error occurred here!', err.stack)
      process.exit(1)
    })
}