async _get ({ key, specOptions: { roleArn }, keyOptions: { versionStage } }) {
    this._logger.info(`fetching secret ${key} on version stage ${versionStage} from AliCloud Secret Manager using role ${roleArn}`)
    const getSecretValueRequest = new GetSecretValueRequest({
      secretName: key,
      versionStage: versionStage
    })

    const client = this._getClient({ specOptions: { roleArn } })
    const value = await client.getSecretValue(getSecretValueRequest)

    return value.secretData.toString('utf-8')
  }
Get secret property value from Alibaba Cloud KMS Secrets Manager.
@param {string} key - Key used to store secret property value in Alibaba Cloud KMS Secrets Manager.
@returns {Promise} Promise object representing secret property value.