index.js

const { execFile } = require('child_process');
const fs = require('fs');
const util = require('util');
const readFile = util.promisify(fs.readFile);
const path = require('path');
const mime = require('mime-types');
const cfnCR = require('cfn-custom-resource');

const AWS = require('aws-sdk');
var glob = require('glob');

const s3 = new AWS.S3();
exports.handler = async message => {
  console.log(message);
  try {
    const tmpDir = `/tmp/react-front-end${process.pid}`;

    const npm = 'npm';
    await spawnPromise('rm', ['-rf', tmpDir]);
    await spawnPromise('cp', ['-R', 'front-end/', tmpDir]);
    await spawnPromise(
      npm,
      ['--production',
        '--no-progress',
        '--loglevel=error',
        '--cache', path.join('/tmp', 'npm'),
        '--userconfig', path.join('/tmp', 'npmrc'),
        'install'
      ],
      {cwd: tmpDir}
    );
    await spawnPromise(
      npm,
      ['--production',
        '--no-progress',
        '--loglevel=error',
        '--cache', path.join('/tmp', 'npm'),
        '--userconfig', path.join('/tmp', 'npmrc'),
        'run', 'build'
      ],
      {cwd: tmpDir}
    );

    const builtPaths = glob.sync(`${tmpDir}/build/**/*`);
    console.log(builtPaths);
    builtPaths.forEach(async (path) => {
      if (!fs.lstatSync(path).isFile()) {
        return;
      }
      const mimeType = mime.lookup(path) || 'application/octet-stream';
      console.log(mimeType);
      const fileHandle = await readFile(path);
      const key = path.replace(`${tmpDir}/build/`, '');

      const params = {
        ACL: 'public-read',
        ContentType: mimeType,
        Body: fileHandle,
        Bucket: process.env.BUCKET_NAME,
        Key: key
      };
      console.log(params);
      const s3Response = await s3.putObject(params).promise();
      console.log(s3Response);
    });
  } catch (error) {
    console.log(error);
    await cfnCR.sendFailure(error.message, message);
  } finally {
    await cfnCR.sendSuccess('deployFrontEnd', {}, message);
  }
};

function spawnPromise (command, args, options) {
  console.log(`Running \`${command} '${args.join("' '")}'\`...`);

  options = options || {};

  if (!options.env) {
    options.env = {};
  }

  Object.assign(options.env, process.env);

  return new Promise((resolve, reject) => {
    execFile(command, args, options, (err, stdout, stderr) => {
      console.log('STDOUT:');
      console.log(stdout);
      console.log('STDERR:');
      console.log(stderr);

      if (err) {
        err.stdout = stdout;
        err.stderr = stderr;

        reject(err);
      } else {
        resolve({stdout: stdout, stderr: stderr});
      }
    });
  });
}