serverless/lib/utils/fs/create-zip-file.js

import fs from 'fs';
import path from 'path';
import archiver from 'archiver';
import BbPromise from 'bluebird';
import walkDirSync from './walk-dir-sync.js';

async function createZipFile(srcDirPath, outputFilePath) {
  const files = walkDirSync(srcDirPath).map((file) => ({
    input: file,
    output: file.replace(path.join(srcDirPath, path.sep), ''),
  }));

  return new BbPromise((resolve, reject) => {
    const output = fs.createWriteStream(outputFilePath);
    const archive = archiver('zip', {
      zlib: { level: 9 },
    });

    output.on('open', () => {
      archive.pipe(output);

      files.forEach((file) => {
        // TODO: update since this is REALLY slow
        if (fs.lstatSync(file.input).isFile()) {
          archive.append(fs.createReadStream(file.input), { name: file.output });
        }
      });

      archive.finalize();
    });

    archive.on('error', (err) => reject(err));
    output.on('close', () => resolve(outputFilePath));
  });
}

export default createZipFile;