common.js

/*
 * This file is part of the xPack project (http://xpack.github.io).
 * Copyright (c) 2017 Liviu Ionescu. All rights reserved.
 *
 * Permission to use, copy, modify, and/or distribute this software
 * for any purpose is hereby granted, under the terms of the MIT license.
 *
 * If a copy of the license was not distributed with this file, it can
 * be obtained from https://opensource.org/license/mit.
 */

'use strict'

/* eslint valid-jsdoc: "error" */
/* eslint max-len: [ "error", 80, { "ignoreUrls": true } ] */

// ----------------------------------------------------------------------------

// https://nodejs.org/docs/latest-v12.x/api/index.htm

import assert from 'assert'
import { spawn } from 'child_process'
import { Console } from 'console'
import fs from 'fs'
import { Writable } from 'stream'
import * as tar from 'tar'
import zlib from 'zlib'

// ----------------------------------------------------------------------------

// ES6: `import { CliHelp } from './utils/cli-helps.js'
import { Xpm } from '../lib/main.js'

// ----------------------------------------------------------------------------

/**
 * Test common options, like --version, --help, etc.
 */

// ----------------------------------------------------------------------------

const nodeBin = process.env.npm_node_execpath || process.env.NODE ||
  process.execPath
const executableName = './bin/xpm.js'
const programName = 'xpm'

/**
 * @class Main
 */
// export
export class Common {
  /**
   * @summary Run xpm in a separate process.
   *
   * @async
   * @param {string[]} args Command line arguments
   * @param {Object} spawnOpts Optional spawn options.
   * @returns {{code: number, stdout: string, stderr: string}} Exit
   *  code and captured output/error streams.
   *
   * @description
   * Spawn a separate process to run node with the given arguments and
   * return the exit code and the stdio streams captured in strings.
   */
  static async xpmCli (args, spawnOpts = {}) {
    return new Promise((resolve, reject) => {
      spawnOpts.env = spawnOpts.env || process.env

      // Runs in project root.
      // console.log(`Current directory: ${process.cwd()}`)
      let stdout = ''
      let stderr = ''
      const cmd = [executableName]
      const child = spawn(nodeBin, cmd.concat(args), spawnOpts)

      assert(child.stderr)
      child.stderr.on('data', (chunk) => {
        // console.log(chunk.toString())
        stderr += chunk
      })

      assert(child.stdout)
      child.stdout.on('data', (chunk) => {
        // console.log(chunk.toString())
        stdout += chunk
      })

      child.on('error', (err) => {
        reject(err)
      })

      child.on('close', (code) => {
        resolve({ code, stdout, stderr })
      })
    })
  }

  /**
   * @summary Run xpm as a library call.
   *
   * @async
   * @param {string[]} args Command line arguments
   * @param {Object} ctx Optional context.
   * @returns {{code: number, stdout: string, stderr: string}} Exit
   *  code and captured output/error streams.
   *
   * @description
   * Call the application directly, as a regular module, and return
   * the exit code and the stdio streams captured in strings.
   */
  static async xpmLib (args, ctx = null) {
    assert(Xpm !== null, 'no application class')
    // Create two streams to local strings.
    let stdout = ''
    const ostream = new Writable({
      write (chunk, encoding, callback) {
        stdout += chunk.toString()
        callback()
      }
    })

    let stderr = ''
    const errstream = new Writable({
      write (chunk, encoding, callback) {
        stderr += chunk.toString()
        callback()
      }
    })

    const _console = new Console(ostream, errstream)
    const context = await Xpm.initialiseContext(ctx, programName, _console)
    const app = new Xpm(context)
    const code = await app.main(args)
    return { code, stdout, stderr }
  }

  /**
   * @summary Extract files from a .tgz archive into a folder.
   *
   * @async
   * @param {string} tgzPath Path to archive file.
   * @param {string} destPath Path to destination folder.
   * @returns {undefined} Nothing.
   */
  static async extractTgz (tgzPath, destPath) {
    return new Promise((resolve, reject) => {
      fs.createReadStream(tgzPath)
        .on('error', (er) => { reject(er) })
        .pipe(zlib.createGunzip())
        .on('error', (er) => { reject(er) })
        .pipe(tar.Extract({ path: destPath }))
        .on('error', (er) => { reject(er) })
        .on('end', () => { resolve() })
    })
  }
}

// ----------------------------------------------------------------------------
// Node.js specific export definitions.

// By default, `module.exports = {}`.
// The Main class is added as a property to this object.

// module.exports.Common = Common

// In ES6, it would be:
// export class Common { ... }
// ...
// import { Common } from 'common.js'

// ----------------------------------------------------------------------------