Elasticsearch 操作

集群健康检查

取得健康状态

GET /_cat/health?v

返回：

epoch      timestamp cluster       status node.total node.data shards pri relo init unassign pending_tasks max_task_wait_time active_shards_percent
1535248805 10:00:05  elasticsearch yellow          1         1      1   1    0    0        1             0                  -                 50.0%

健康状态分类

green：索引的primary shard和replica shard都是active状态的

yellow：索引的primary shard都是active状态的，但是部分replica shard不是active状态，处于不可用的状态、

red：不是所有索引的primary shard都是active状态的，部分索引有数据丢失了

当前处于yellow状态是因为目前只启动了一个es进程，只有一个节点node，这是不安全的。这个节点的primary shard 有分配，但是replica shard 没有节点分配，因此是yellow状态。

快速查看集群有哪些节点

 GET /_cat/indices?v

health status index   uuid                   pri rep docs.count docs.deleted store.size pri.store.size
yellow open   .kibana xSbUffi_SYGYIhPtiMxH5w   1   1          1            0      3.1kb          3.1kb

简单的索引操作

创建索引：PUT /test_index?pretty

返回：

{
  "acknowledged": true,
  "shards_acknowledged": true
}

删除索引：DELETE /test_index?pretty

返回：

{
  "acknowledged": true
}

CURD 操作Demo

（1）新增商品：新增文档，建立索引

PUT /ecommerce/product/1
{
    "name" : "xi jie jing",
    "desc" :  "gaoxiao qing jie",
    "price" :  30,
    "producer" :      "xijiejing producer",
    "tags": [ "qingxi", "wuzhi" ]
}

 返回：

{
  "_index": "ecommerce",
  "_type": "product",
  "_id": "1",
  "_version": 1,
  "result": "created",
  "_shards": {
    "total": 2,
    "successful": 1,
    "failed": 0
  },
  "created": true
}

新增

PUT /ecommerce/product/2
{
    "name" : "niunai",
    "desc" :  "mengniu niunai",
    "price" :  25,
    "producer" :      "mengniuniunai producer",
    "tags": [ "niunai" ]
}

返回：

{
  "_index": "ecommerce",
  "_type": "product",
  "_id": "2",
  "_version": 1,
  "result": "created",
  "_shards": {
    "total": 2,
    "successful": 1,
    "failed": 0
  },
  "created": true
}

（2）查询商品：检索文档

GET /ecommerce/product/1

返回：

{
  "_index": "ecommerce",
  "_type": "product",
  "_id": "1",
  "_version": 1,
  "found": true,
  "_source": {
    "name": "xi jie jing",
    "desc": "gaoxiao qing jie",
    "price": 30,
    "producer": "xijiejing producer",
    "tags": [
      "qingxi",
      "wuzhi"
    ]
  }
}

（3）修改商品：替换文档

PUT /ecommerce/product/1
{
    "name" : "jiaqiangban gaolujie yagao",
    "desc" :  "gaoxiao meibai",
    "price" :  30,
    "producer" :      "gaolujie producer",
    "tags": [ "meibai", "fangzhu" ]
}

返回：

{
  "_index": "ecommerce",
  "_type": "product",
  "_id": "1",
  "_version": 2,
  "result": "updated",
  "_shards": {
    "total": 2,
    "successful": 1,
    "failed": 0
  },
  "created": false
}

（5）删除商品：删除文档

DELETE /ecommerce/product/1

{
  "found": true,
  "_index": "ecommerce",
  "_type": "product",
  "_id": "1",
  "_version": 3,
  "result": "deleted",
  "_shards": {
    "total": 2,
    "successful": 1,
    "failed": 0
  }
}

多种搜索方式

1 query string search

GET /ecommerce/product/_search 

{
  "took": 12,
  "timed_out": false,
  "_shards": {
    "total": 5,
    "successful": 5,
    "failed": 0
  },
  "hits": {
    "total": 1,
    "max_score": 1,
    "hits": [
      {
        "_index": "ecommerce",
        "_type": "product",
        "_id": "2",
        "_score": 1,
        "_source": {
          "name": "niunai",
          "desc": "mengniu niunai",
          "price": 25,
          "producer": "mengniuniunai producer",
          "tags": [
            "niunai"
          ]
        }
      }
    ]
  }
}

字段说明：

took：耗时

timed_out：是否超时

_shards：数据拆成了5个分片

hits.total：查询结果的数量，3个document

hits.max_score：匹配分数，越相关，就越匹配，分数也高

hits.hits：包含了匹配搜索的document的详细数据

此方法只是临时在命令行使用，例如crul，不适用于复杂查询。

2 query DSL

可以用json语法查询语法

查询所有的商品：

GET /ecommerce/product/_search
{
  "query": { "match_all": {} }
}

按照价格排序：

GET /ecommerce/product/_search
{
    "query" : {
        "match" : {
            "name" : "yagao"
        }
    },
    "sort": [
        { "price": "desc" }
    ]
}

3 query filter

搜索商品名称包含yagao，而且售价大于25元的商品

GET /ecommerce/product/_search
{
    "query" : {
        "bool" : {
            "must" : {
                "match" : {
                    "name" : "yagao" 
                }
            },
            "filter" : {
                "range" : {
                    "price" : { "gt" : 25 } 
                }
            }
        }
    }
}

4、full-text search（全文检索）

GET /ecommerce/product/_search
{
    "query" : {
        "match" : {
            "producer" : "yagao producer"
        }
    }
}

源码面前，了无秘密