AmazonTransport.js

const { Transport } = require('@elastic/elasticsearch')

function awaitAwsCredentials (awsConfig) {
  return new Promise((resolve, reject) => {
    awsConfig.getCredentials((err) => {
      err ? reject(err) : resolve()
    })
  })
}

module.exports = awsConfig => {
  class AmazonTransport extends Transport {
    request (params, options = {}, callback = undefined) {
      // options is optional, so if it is omitted, options will be the callback
      if (typeof options === 'function') {
        callback = options
        options = {}
      }

      // check if getCredentials exists, if so this is an aws-sdk v2 global config object
      if (typeof awsConfig.getCredentials !== 'function') {
        if (typeof callback === 'undefined') {
          return super.request(params, options)
        } else {
          super.request(params, options, callback)
        }
      } else {
        // Promise support
        if (typeof callback === 'undefined') {
          return awaitAwsCredentials(awsConfig)
            .then(() => super.request(params, options))
        }

        // Callback support
        awaitAwsCredentials(awsConfig)
          .then(() => super.request(params, options, callback))
          .catch(callback)
      }
    }
  }

  return AmazonTransport
}