code: function signAWSRequest({ credentials, request }) {
    const signer = new AWS.Signers.V4(request, 'es')
    signer.addAuthorization(credentials, new Date())
    return request
  }
docs: Signs an AWS HTTP Request object with the provided AWS Credentials object
  @param {Object} param.credentials - aws credentials object
  @param {Object} param.request     - aws http request object
  @return {Object} signed request