elasticsearchwriter不能用

运行报错：
Caused by: java.lang.IllegalArgumentException: Preemptive authentication set without credentials provider
at io.searchbox.client.config.HttpClientConfig$Builder.build(HttpClientConfig.java:301)
at com.alibaba.datax.plugin.writer.elasticsearchwriter.ESClient.createClient(ESClient.java:65)
at com.alibaba.datax.plugin.writer.elasticsearchwriter.ESWriter$Job.prepare(ESWriter.java:49)
at com.alibaba.datax.core.job.JobContainer.prepareJobWriter(JobContainer.java:724)
at com.alibaba.datax.core.job.JobContainer.prepare(JobContainer.java:309)
at com.alibaba.datax.core.job.JobContainer.start(JobContainer.java:115)
... 3 more
本地的elasticsearch环境没有配置auth。
job相关配置如下：
"writer": {
"name": "elasticsearchwriter",
"parameter": {
"endpoint": "http://localhost:9200",
"index": "xxx",
"type": "xxx",
"accessId": "",
"accessKey": "",
"cleanup": true,
"settings": {"index" :{"number_of_shards": 5, "number_of_replicas": 0}},
"discovery": false,
"batchSize": 1000,
"splitter": ",",
……
}

Start in ESClient.java at createClient, especially the HttpClientConfig.Builder call reported at line 301. Reproduce the job against the unauthenticated localhost:9200 endpoint and compare the accessId/accessKey handling with the authentication options. Done means the provided no-auth configuration can prepare the Elasticsearch writer without the credentials-provider exception.

Written by the indexing model from the issue text.