在docker中运行elasticsearch时go程序无法连接到节点

错误信息：

panic: no active connection found: no Elasticsearch node available

在docker中运行es时，默认启动sniffing 模式，es自动查找节点， 要确保Elasticsearch返回可从容器外部访问的IP地址。

解决方式为关闭sniffing或者配置es返回的主机地址，参考 https://github.com/olivere/elastic/wiki/Docker

1. 配置elasticsearch

    - 将network.publish_host和network.bind_host配置为可从容器外部访问的地址

    - 配置network.host （不用再单独配置network.bind_host 和 network.publish_host）

2. 禁用 sniffing

     elastic.SetSniff(false)

# 查看节点信息，详细返回参数：Nodes Info
curl -XGET '0.0.0.0:9200/_nodes/http?pretty'
{
  "_nodes" : {
    "total" : 1,
    "successful" : 1,
    "failed" : 0
  },
  "cluster_name" : "escluster",
  "nodes" : {
    "nodename" : {
      "name" : "name",
      "transport_address" : "xxxx:9300",
      "host" : "xxxx",
      "ip" : "xxxx",
      "version" : "6.4.1",
      "build_flavor" : "default",
      "build_type" : "tar",
      "build_hash" : "e36acdb",
      "roles" : [
        "master",
        "data",
        "ingest"
      ],
      "attributes" : {
        "ml.machine_memory" : "16826724352",
        "xpack.installed" : "true",
        "ml.max_open_jobs" : "20",
        "ml.enabled" : "true"
      },
      "http" : {
        "bound_address" : [
          "0.0.0.0:9200"  //http服务绑定的主机地址，配置为可从容器外部访问的地址
        ],
        "publish_address" : "xxxx:9200", //http客户端发布的主机地址，配置为可从容器外部访问的地址
        "max_content_length_in_bytes" : 104857600
      }
    }
  }
}