.js

function getDockerStuff() {
  return new Promise((resolve, reject) => {
    let data = '';
    
    foo.create(name, template, config, function onComplete(exitCode, errors) {
      if (exitCode !== null) {
        reject(errors);
      } else {
        resolve(data);
      }
    }, function onData(str) {
      data += str;
    });
  });
}