17基于groovy脚本更新document

es，其实是有个内置的脚本支持的，可以基于groovy脚本实现各种各样的复杂操作 基于groovy脚本，如何执行partial update？ 使用es scripting module，我们会在后续接触到，这里就只是初步了解一下

准备数据，先创建一条数据

PUT /test_index/test_type/11
{
  "num": 0,
  "tags": []
}

响应结果

{
  "_index": "test_index",
  "_type": "test_type",
  "_id": "11",
  "_version": 1,
  "result": "created",
  "_shards": {
    "total": 2,
    "successful": 1,
    "failed": 0
  },
  "created": true
}

查看

GET /test_index/test_type/11

响应结果

{
  "_index": "test_index",
  "_type": "test_type",
  "_id": "11",
  "_version": 1,
  "found": true,
  "_source": {
    "num": 0,
    "tags": []
  }
}

（1）内置脚本

POST /test_index/test_type/11/_update
{
   "script" : "ctx._source.num+=1"
}

ctx._ source就能获得数据对应的_ source

ctx._ source.num就获得数据对应的_ source下的num

对num执行+1操作

响应结果

{
  "_index": "test_index",
  "_type": "test_type",
  "_id": "11",
  "_version": 2,
  "result": "updated",
  "_shards": {
    "total": 2,
    "successful": 1,
    "failed": 0
  }
}

再次查看

{
  "_index": "test_index",
  "_type": "test_type",
  "_id": "11",
  "_version": 2,
  "found": true,
  "_source": {
    "num": 1,
    "tags": []
  }
}

（2）外部脚本

对document的tags里新增一个tag1

在…\elasticsearch-5.6.0\config\scripts下创建一个test-add-tags.groovy文件

在文件中添加

ctx._source.tags+=new_tag

发送命令，指定文件

POST /test_index/test_type/11/_update
{
  "script": {
    "lang": "groovy", 
    "file": "test-add-tags",
    "params": {
      "new_tag": "tag1"
    }
  }
}

响应结果

{
  "_index": "test_index",
  "_type": "test_type",
  "_id": "11",
  "_version": 3,
  "result": "updated",
  "_shards": {
    "total": 2,
    "successful": 1,
    "failed": 0
  }
}

再次查看

{
  "_index": "test_index",
  "_type": "test_type",
  "_id": "11",
  "_version": 3,
  "found": true,
  "_source": {
    "num": 1,
    "tags": [
      "tag1"
    ]
  }
}

（3）用脚本删除文档

在…\elasticsearch-5.6.0\config\scripts下创建一个test-delete-document.groovy文件

在文件中添加脚本

ctx.op = ctx._source.num == count ? 'delete' : 'none'

删除

POST /test_index/test_type/11/_update
{
  "script": {
    "lang": "groovy",
    "file": "test-delete-document",
    "params": {
      "count": 1
    }
  }
}

响应结果

{
  "_index": "test_index",
  "_type": "test_type",
  "_id": "11",
  "_version": 4,
  "result": "deleted",
  "_shards": {
    "total": 2,
    "successful": 1,
    "failed": 0
  }
}

result:deleted表示删除成功

查看

{
  "_index": "test_index",
  "_type": "test_type",
  "_id": "11",
  "found": false
}

数据已经没了

（4）upsert操作

对于partial update来说，如果指定的document不存在，会报错error

POST /test_index/test_type/11/_update
{
  "doc": {
    "num": 1
  }
}

响应结果

{
  "error": {
    "root_cause": [
      {
        "type": "document_missing_exception",
        "reason": "[test_type][11]: document missing",
        "index_uuid": "mnlKvBhVRMykVwAAdYIH0g",
        "shard": "4",
        "index": "test_index"
      }
    ],
    "type": "document_missing_exception",
    "reason": "[test_type][11]: document missing",
    "index_uuid": "mnlKvBhVRMykVwAAdYIH0g",
    "shard": "4",
    "index": "test_index"
  },
  "status": 404
}

如果指定的document不存在，就执行upsert中的初始化操作；如果指定的document存在，就执行doc或者script指定的partial update操作

POST /test_index/test_type/11/_update
{
   "script" : "ctx._source.num+=1",
   "upsert": {
       "num": 0,
       "tags": []
   }
}

响应结果 document不存在，执行初始化

{
  "_index": "test_index",
  "_type": "test_type",
  "_id": "11",
  "_version": 1,
  "result": "created",
  "_shards": {
    "total": 2,
    "successful": 1,
    "failed": 0
  }
}

查看

{
  "_index": "test_index",
  "_type": "test_type",
  "_id": "11",
  "_version": 1,
  "found": true,
  "_source": {
    "num": 0,
    "tags": []
  }
}

再次执行

{
  "_index": "test_index",
  "_type": "test_type",
  "_id": "11",
  "_version": 2,
  "result": "updated",
  "_shards": {
    "total": 2,
    "successful": 1,
    "failed": 0
  }
}

查看

{
  "_index": "test_index",
  "_type": "test_type",
  "_id": "11",
  "_version": 2,
  "found": true,
  "_source": {
    "num": 1,
    "tags": []
  }
}