code: protected StreamContext getStreamContext() {
      StreamContext context = new StreamContext();
      solrClientCache = new SparkSolrClientCache(cloudSolrClient, httpSolrClient);
      context.setSolrClientCache(solrClientCache);
      context.numWorkers = numWorkers;
      context.workerID = workerId;
      return context;
    }
docs: We have to set the streaming context so that we can pass our own cloud client with authentication