pipeline 和 painless对文档数据进行预处理

女爷i 2022-11-05 00:54 173阅读 0赞

在es中每个节点默认都是ingest节点，可以对即将索引的文档数据进行预处理，比如修改文档字段的默认值、添加新的字段、字符串转数组等，es可以通过pipeline或者painless方式对数据进行预处理。Pipeline:数据管道，对于进入管道的数据进行有序的加工，它由一系列的processer处理器组成，每个处理器都可以单独做预处理，在es中内置了一系列的处理器，也可以扩展，pipeline的使用需要先在ES订阅pipeline，在更新文档或者重建索引的时候指定pipeline；painless脚本，在数据更新时候，可以用painless脚本进行预处理，在数据查询时，可以拦截数据修改返回值。

1 初始化数据
    DELETE tech_blogs
    
    PUT tech_blogs/_doc/1
    {
      "title":"Introducing big data......",
      "tags":"hadoop,elasticsearch,spark",
      "content":"You konw, for big data"
    }
    
    
    
    2 pipeline 测试 tags字段转数组
    POST _ingest/pipeline/_simulate
    {
      "pipeline": {
        "description": "to split blog tags",
        "processors": [
          {
            "split": {
              "field": "tags",
              "separator": ","
            }
          }
        ]
      },
      "docs": [
        {
          "_index": "index",
          "_id": "id",
          "_source": {
            "title": "Introducing big data......",
            "tags": "hadoop,elasticsearch,spark",
            "content": "You konw, for big data"
          }
        },
        {
          "_index": "index",
          "_id": "idxx",
          "_source": {
            "title": "Introducing cloud computering",
            "tags": "openstack,k8s",
            "content": "You konw, for cloud"
          }
        }
      ]
    }
    
    
    3 同时为文档，增加一个字段。blog查看量
    POST _ingest/pipeline/_simulate
    {
      "pipeline": {
        "description": "to split blog tags",
        "processors": [
          {
            "split": {
              "field": "tags",
              "separator": ","
            }
          },
    
          {
            "set":{
              "field": "views",
              "value": 0
            }
          }
        ]
      },
    
      "docs": [
        {
          "_index":"index",
          "_id":"id",
          "_source":{
            "title":"Introducing big data......",
      "tags":"hadoop,elasticsearch,spark",
      "content":"You konw, for big data"
          }
        },
    
    
        {
          "_index":"index",
          "_id":"idxx",
          "_source":{
            "title":"Introducing cloud computering",
      "tags":"openstack,k8s",
      "content":"You konw, for cloud"
          }
        }
    
        ]
    }
    
    
    4 在ES添加注册一个 Pipeline
    PUT _ingest/pipeline/blog_pipeline
    {
      "description": "a blog pipeline",
      "processors": [
          {
            "split": {
              "field": "tags",
              "separator": ","
            }
          },
    
          {
            "set":{
              "field": "views",
              "value": 0
            }
          }
        ]
    }
    
    5查看Pipleline
    GET _ingest/pipeline/blog_pipeline
    
    6测试pipeline
    POST _ingest/pipeline/blog_pipeline/_simulate
    {
      "docs": [
        {
          "_source": {
            "title": "Introducing cloud computering",
            "tags": "openstack,k8s",
            "content": "You konw, for cloud"
          }
        }
      ]
    }
    
    7不使用pipeline更新数据
    PUT tech_blogs/_doc/1
    {
      "title":"Introducing big data......",
      "tags":"hadoop,elasticsearch,spark",
      "content":"You konw, for big data"
    }
    
    8使用pipeline更新数据
    PUT tech_blogs/_doc/2?pipeline=blog_pipeline
    {
      "title": "Introducing cloud computering",
      "tags": "openstack,k8s",
      "content": "You konw, for cloud"
    }
    
    9查看两条数据，一条被处理，一条未被处理
    POST tech_blogs/_search
    {}
    
    
    10 重建索引update_by_query 会导致错误
    POST tech_blogs/_update_by_query?pipeline=blog_pipeline
    {
    }
    
    
    11增加update_by_query的条件（对没预处理的文档重建）
    POST tech_blogs/_update_by_query?pipeline=blog_pipeline
    {
        "query": {
            "bool": {
                "must_not": {
                    "exists": {
                        "field": "views"
                    }
                }
            }
        }
    }
    
    
    12 增加一个 通过painless脚本添加content_length字段
    POST _ingest/pipeline/_simulate
    {
      "pipeline": {
        "description": "to split blog tags",
        "processors": [
          {
            "split": {
              "field": "tags",
              "separator": ","
            }
          },
          {
            "script": {
              "source": """
              if(ctx.containsKey("content")){
                ctx.content_length = ctx.content.length();
              }else{
                ctx.content_length=0;
              }
    
    
              """
            }
          },
    
          {
            "set":{
              "field": "views",
              "value": 0
            }
          }
        ]
      },
    
      "docs": [
        {
          "_index":"index",
          "_id":"id",
          "_source":{
            "title":"Introducing big data......",
      "tags":"hadoop,elasticsearch,spark",
      "content":"You konw, for big data"
          }
        },
    
    
        {
          "_index":"index",
          "_id":"idxx",
          "_source":{
            "title":"Introducing cloud computering",
      "tags":"openstack,k8s",
      "content":"You konw, for cloud"
          }
        }
    
        ]
    }
    
    13 重新初始化数据
    DELETE tech_blogs
    PUT tech_blogs/_doc/1
    {
      "title":"Introducing big data......",
      "tags":"hadoop,elasticsearch,spark",
      "content":"You konw, for big data",
      "views":0
    }
    
    14 通过painless脚本给view字段值+100
    POST tech_blogs/_update/1
    {
      "script": {
        "source": "ctx._source.views += params.new_views",
        "params": {
          "new_views":100
        }
      }
    }
    
    
    15 查看views计数
    POST tech_blogs/_search
    { 
    
    }
    
    
    16 保存painless脚本在 Cluster State
    POST _scripts/update_views
    {
      "script":{
        "lang": "painless",
        "source": "ctx._source.views += params.new_views"
      }
    }
    
    17 测试对其值增加1000
    POST tech_blogs/_update/1
    {
      "script": {
        "id": "update_views",
        "params": {
          "new_views":1000
        }
      }
    }
    
    
    18 在查询时通过painless脚本对查询结果view字段添加一个随机值
    GET tech_blogs/_search
    {
      "script_fields": {
        "rnd_views": {
          "script": {
            "lang": "painless",
            "source": """
              java.util.Random rnd = new Random();
              doc['views'].value+rnd.nextInt(1000);
            """
          }
        }
      },
      "query": {
        "match_all": {}
      }
    }