downloader.js

const fs = require('fs');
const path = require('path');
const shell = require('shelljs');
const download = require('download');
const decompress = require('decompress');
const unzip = require('decompress-unzip');
const untargz = require('decompress-targz');
const untarbz2 = require('decompress-tarbz2');

process.on('unhandledRejection', (reason, _) => {
  shell.echo(String(reason));
  shell.exit(1);
  throw reason;
});
process.on('uncaughtException', (error) => {
  shell.echo(String(error));
  shell.exit(1);
  throw error;
});

/**
 * @param url {string}        Download URL
 * @param targetFile {string} Path to the file to copy from the decompressed archive
 * @param filePrefix {string} Prefix of the file name found in the archive
 * @param force {boolean}     Whether to download even if the target file exists. `false` by default.
 */
exports.downloadUnzipFile = async (
  url,
  targetFile,
  filePrefix,
  force = false
) => {
  if (fs.existsSync(targetFile) && !force) {
    shell.echo(`Skipping download because file already exists: ${targetFile}`);
    return;
  }
  if (!fs.existsSync(path.dirname(targetFile))) {
    if (shell.mkdir('-p', path.dirname(targetFile)).code !== 0) {
      shell.echo('Could not create new directory.');
      shell.exit(1);
    }
  }

  const downloads = path.join(__dirname, '..', 'downloads');
  if (shell.rm('-rf', targetFile, downloads).code !== 0) {
    shell.exit(1);
  }

  shell.echo(`>>> Downloading from '${url}'...`);
  const data = await download(url);
  shell.echo(`<<< Download succeeded.`);

  shell.echo('>>> Decompressing...');
  const files = await decompress(data, downloads, {
    plugins: [unzip(), untargz(), untarbz2()],
  });
  if (files.length === 0) {
    shell.echo('Error ocurred while decompressing the archive.');
    shell.exit(1);
  }
  const fileIndex = files.findIndex((f) => f.path.startsWith(filePrefix));
  if (fileIndex === -1) {
    shell.echo(
      `The downloaded artifact does not contain any file with prefix ${filePrefix}.`
    );
    shell.exit(1);
  }
  shell.echo('<<< Decompressing succeeded.');

  if (
    shell.mv('-f', path.join(downloads, files[fileIndex].path), targetFile)
      .code !== 0
  ) {
    shell.echo(`Could not move file to target path: ${targetFile}`);
    shell.exit(1);
  }
  if (!fs.existsSync(targetFile)) {
    shell.echo(`Could not find file: ${targetFile}`);
    shell.exit(1);
  }
  shell.echo(`Done: ${targetFile}`);
};

/**
 * @param url {string}        Download URL
 * @param targetDir {string}  Directory into which to decompress the archive
 * @param targetFile {string} Path to the main file expected after decompressing
 * @param force {boolean}     Whether to download even if the target file exists
 * @param decompressOptions {import('decompress').DecompressOptions}
 */
exports.downloadUnzipAll = async (
  url,
  targetDir,
  targetFile,
  force,
  decompressOptions = undefined
) => {
  if (fs.existsSync(targetFile) && !force) {
    shell.echo(`Skipping download because file already exists: ${targetFile}`);
    return;
  }
  if (!fs.existsSync(targetDir)) {
    if (shell.mkdir('-p', targetDir).code !== 0) {
      shell.echo('Could not create new directory.');
      shell.exit(1);
    }
  }

  shell.echo(`>>> Downloading from '${url}'...`);
  const data = await download(url);
  shell.echo(`<<< Download succeeded.`);

  shell.echo('>>> Decompressing...');
  let options = {
    plugins: [unzip(), untargz(), untarbz2()],
  };
  if (decompressOptions) {
    options = Object.assign(options, decompressOptions);
  }
  const files = await decompress(data, targetDir, options);
  if (files.length === 0) {
    shell.echo('Error ocurred while decompressing the archive.');
    shell.exit(1);
  }
  shell.echo('<<< Decompressing succeeded.');

  if (!fs.existsSync(targetFile)) {
    shell.echo(`Could not find file: ${targetFile}`);
    shell.exit(1);
  }
  shell.echo(`Done: ${targetFile}`);
};