title: Impossible to read Kafka message value
body: <p>I'm using a simple producer in order to produce a message in kafka.
  This message is a json object.</p>
  
  <p>This is the code of my producer : </p>
  
  <pre><code>const kafka = require('kafka-node');
    const Producer = kafka.Producer;
    const KeyedMessage = kafka.KeyedMessage;
    const Offset = kafka.Offset;
    const Client = kafka.Client;
    const p = 0;
    const a = 0;
    const topic = 'claims';
  
    const client = new Client('192.168.99.100:2181');
    const producer = new Producer(client, { requireAcks: 1 });
  
    producer.on('error', function (err) {
      done.fail(err);
    });
  
    producer.on('ready', function () {
      const message = {status: 'Created', id_claims: '12345'};
  
      producer.send([
        { topic: topic, partition: p, messages: message, attributes: a }
      ], function (err, result) {
        expect(result).not.toBeNull();
        expect(err).toBeNull();
        done();
      });
    });
  </code></pre>
  
  <p>But then when i try to read the content of this message I always get </p>
  
  <blockquote>
    <p>[Object object]</p>
  </blockquote>
  
  <p>This is the code of my consumer :</p>
  
  <pre><code>'use strict';
  
  const util = require('util')
  
  const kafka = require('kafka-node');
  const Consumer = kafka.Consumer;
  const Offset = kafka.Offset;
  const Client = kafka.Client;
  const topic = 'claims';
  
  const client = new Client('192.168.99.100:2181');
  const topics = [
      {topic: topic, partition: 0}
  ];
  const options = { autoCommit: false, fetchMaxWaitMs: 1000, fetchMaxBytes: 1024 * 1024 };
  
  const consumer = new Consumer(client, topics, options);
  const offset = new Offset(client);
  
  consumer.on('message', function (message) {
    console.log(JSON.stringify(message.value));
    console.log("Value: %j", message.value);
    console.log("Value: %o", message.value);
    console.log('Value: ' + util.inspect(message.value, 10));
    console.log(util.inspect(message.value, {showHidden: false, depth: null}));
  });
  
  consumer.on('error', function (err) {
    console.log(err);
  });
  </code></pre>
  
  <p>Every method I try in the handler return the same result : [Object object]</p>