old_contents: const plivo = require('plivo');
  
  class Plivo {
    constructor (Config) {
      this.config = Config;
      const authId = this.config.get('sms.plivo.authId');
      const authToken = this.config.get('sms.plivo.authToken');
      if (!authId) throw new Error('Auth Id not found in Plivo config.');
      if (!authToken) throw new Error('Auth Token not found in Plivo config.');
      this.plivo = plivo.RestAPI({ authId, authToken });
    }
  
    send (message, config) {
      if (config) this.config = config;
      return new Promise((resolve, reject) => {
        this.plivo.send_message({
          src: message.from,
          dst: message.to,
          text: message.text
        }, (status, response) => {
          if (status < 200 || status > 299) {
            return reject(`${status} response - ${response.error}`);
          }
          return resolve(response.message_uuid);
        });
      });
    }
  }
  
  module.exports = Plivo;
  
new_contents: const plivo = require('plivo');
  
  class Plivo {
    constructor (Config) {
      this.config = Config;
      const authId = this.config.get('sms.plivo.authId');
      const authToken = this.config.get('sms.plivo.authToken');
      if (!authId) throw new Error('Auth Id not found in Plivo config.');
      if (!authToken) throw new Error('Auth Token not found in Plivo config.');
      this.plivo = plivo.RestAPI({ authId, authToken });
    }
  
    send (message, config) {
      if (config) this.config = config;
      return new Promise((resolve, reject) => {
        this.plivo.send_message({
          src: message.from,
          dst: message.to,
          text: message.text
        }, (status, response) => {
          if (status < 200 || status > 299) {
            return reject(`${status} response - ${response}`);
          }
          return resolve(response.message_uuid);
        });
      });
    }
  }
  
  module.exports = Plivo;
  
subject: fix error logger