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ELASTIC 搜索开发实战-笔记

更新时间:2022-08-22 14:28:58

本文是《Elastic 搜索开发实战 》的学习笔记

《Elastic 搜索开发实战 》

需求描述:

  • 智能补全提示
  • 结果的高亮显示
  • 结果的聚合统计和过滤
  • 相关搜索结果的推荐
  • 短语纠错(fuzziness)
  • 数据的实时同步与更新(logstash)
  • 查得到
  • 查得全
  • 查得准
  • 支持同义词
  • 支持简繁体
  • 支持拼音(pinyin)
  • 支持 PPT 的搜索
  • 支持自定义排序,按时间,按相关度
  • 支持结果过滤,按分类、按标签、按时间范围等
  • 搜索结果展示待加强,UI 设计

版本:

  • Elasticsearch v6.2.4
  • Kibana v6.2.4
  • Logstash v6.2.4

kibana dev tools快捷键

command + i 自动缩进

command + enter 提交请求

常用 API 介绍

1、增删改查

# 创建文档
POST twitter/doc/1
{
  "name": "Jack",
  "age": 30
}

# 取回文档
GET twitter/doc/1

# 完全替换
PUT twitter/doc/1
{
  "name": "Jack",
  "age": 35
}

# 部分更新
POST twitter/doc/1/_update
{
  "doc": {
    "name": "Mark"
  }
}

# 删除文档
DELETE twitter/doc/1

2、搜索的使用

# 创建两个索引文档
POST twitter/doc/1
{
  "name": "Jack",
  "age": 30
}

POST twitter/doc/2
{
  "name": "Mark",
  "age": 35
}

# 通过名称搜索
GET twitter/_search?q=Jack

# 通过年龄检索
GET twitter/_search?q=35

# 限定查询年龄字段
GET twitter/_search?q=age:35

# QueryDSL查询表达式
POST twitter/_search
{
  "query": {
    "match": {
      "age": 35
    }
  }
}

3、聚合的使用

# 再创建两个索引文档
POST twitter/doc/3
{
  "name":"john",
  "age":30
}

POST twitter/doc/4
{
  "name":"mark",
  "age":40
}

# 统计年龄的分布情况
POST twitter/_search
{
  "size": 0,
  "aggs": {
    "age_stats": {
      "terms": {
        "field": "age",
        "size": 10
      }
    }
  }
}

聚合查询表达式说明


最外层的 size 为 0 不返回搜索命中的文档,只返回聚合的统计结果,

aggs 就是我们描述聚合查询语句根节点,

使用 terms 聚合类型来对 age 字段的值进行统计,并且只返回前 10 个统计值,

然后这些统计结果我们命名为 age_stats

4、索引的管理

# 查看索引列表
GET _cat/indices?v

# 删除索引
DELETE twitter

# 查看集群的健康状况
GET _cluster/health

字段名

说明

health

索引健康状态,green 表示健康;yellow 表示数据完整,但是缺少副本;red 则表示有数据损坏。

status

索引工作状态,open 表示索引打开中,可以被使用;close 表示索引被关闭,不能使用。

index

索引名称。

uuid

索引的唯一 ID 标识。

pri

索引的主分片个数。

rep

索引的副本分片个数。

docs.count

索引内的文档个数。

docs.deleted

索引内已经删除的文档个数。

搜索示例

数据准备

创建表

CREATE TABLE `blog` (
  `id` int(11) NOT NULL AUTO_INCREMENT COMMENT '主键id',
  `title` varchar(60) DEFAULT NULL COMMENT '标题',
  `author` varchar(60) DEFAULT NULL COMMENT '作者',
  `content` text COMMENT '内容',
  `create_time` datetime DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
  `update_time` datetime DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '更新时间',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB  DEFAULT CHARSET=utf8mb4

获取测试数据

# -*- coding: utf-8 -*-

from pprint import pprint

import requests
from parsel import Selector
from puremysql import PureMysql


def get_data(url):
    """
    获取古诗文网数据
    eg: https://www.gushiwen.cn/
    :return: list
    """
    response = requests.get(url)

    sel = Selector(text=response.text)
    rows = sel.css(".main3 .left .sons")

    lst = []
    for row in rows:

        title = row.css("b::text").extract_first()
        author = row.css(".source").xpath("string(.)").extract_first()
        content = row.css(".contson").xpath("string(.)").extract_first()

        if not title:
            continue

        item = {
            "title": title.strip(),
            "author": author.strip(),
            "content": content.replace('\n', ''),
        }

        pprint(item)
        lst.append(item)

    return lst


def insert_data(lst):
    """
    数据入库
    """
    con = PureMysql(db_url="mysql://root:123456@127.0.0.1:3306/data?charset=utf8")
    table = con.table("blog")
    ret = table.insert(lst)
    con.close()
    print("成功入库", ret)


def main():
    # url = "https://www.gushiwen.cn/"
    for page in range(1, 11):
        url = f"https://www.gushiwen.cn/default.aspx?page={page}"
        lst = get_data(url)
        insert_data(lst)


if __name__ == '__main__':
    main()

logstash同步数据配置

config/jdbc.conf

input {
  jdbc {
    jdbc_driver_library => "mysql-connector-java-8.0.16.jar"
    jdbc_driver_class => "com.mysql.cj.jdbc.Driver"
    jdbc_connection_string => "jdbc:mysql://127.0.0.1:3306/data"
    jdbc_user => "root"
    jdbc_password => "123456"
    statement => "SELECT id, title, content, author, create_time, update_time FROM blog"
    jdbc_paging_enabled => "true"
    jdbc_page_size => "5000"
  }
}

filter {
}

output {
  stdout {
    codec => rubydebug
  }

  elasticsearch {
    index => "blog",
    document_id => "%{id}"
  }
}

同步数据

# 检查配置文件
$ ./bin/logstash -t -f config/jdbc.conf

# 执行配置文件
$ ./bin/logstash -f config/jdbc.conf

问题及处理

处理elasticsearch跨域问题

config/elasticsearch.yml

http.cors.enabled: true
http.cors.allow-origin: "*"

搜索提示

高亮结果显示

POST /blog/_search
{
  "query": {
    "match": {
      "author": "李白"
    }
  },
  "highlight": {
    "fields": {
      "author": {}
    }
  }
}

搜索模板

将查询和参数分离

POST /blog/_search/template
{
  "source": {
    "query": {
      "match": {
        "{{key}}": "{{value}}"
      }
    },
    "size": "{{size}}"
  },
  "params": {
    "key": "author",
    "value": "李白",
    "size": 10
  }
}

其他语句

# 调试模板渲染结果: 
GET _render/template

# 取回模板定义的语法: 
GET _scripts/<templatename>

# 删除模板定义的语法: 
DELETE _scripts/<templatename>

创建模板

POST /_scripts/blog_template_v1
{
  "script": {
    "lang": "mustache",
    "source": {
      "query": {
        "match": {
          "{{key}}": "{{value}}"
        }
      },
      "highlight": {
        "fields": {
          "{{key}}": {}
        }
      },
      "size": "{{size}}"
    }
  }
}

使用模板

POST /blog/_search/template
{
  "id": "blog_template_v1",
  "params": {
    "key": "author",
    "value": "李白",
    "size": 10
  }
}

模糊查询

GET test/_search
{
  "query": {
    "match": {
      "doc":{
        "query": "elastix",
        "fuzziness": "AUTO"
      }
    }
  }
}

优化查询

POST _scripts/blog_template_v1
{
  "script": {
    "lang": "mustache",
    "source": {
      "size": "{{size}}",
      "query": {
        "bool": {
          "should": [
            {
              "prefix": {
                "{{field}}.keyword": {
                  "value": "{{query}}",
                  "boost": 10
                }
              }
            },
            {
              "match_phrase_prefix": {
                "{{field}}": {
                  "query": "{{query}}",
                  "boost": 2
                }
              }
            },
            {
              "match": {
                "{{field}}": "{{query}}"
              }
            }
          ]
        }
      },
      "_source": [
        "title",
        "id",
        "uid",
        "views"
      ]
    }
  }
}

重建索引


# 新建索引
PUT blog_v1

# 查看原索引的mapping
GET blog/_mapping

# 设置索引的mapping
POST blog_v1/doc/_mapping
{
  "doc": {
    "properties": {
      "@timestamp": {
        "type": "date"
      },
      "@version": {
        "type": "text",
        "fields": {
          "keyword": {
            "type": "keyword",
            "ignore_above": 256
          }
        }
      },
      "author": {
        "type": "text",
        "fields": {
          "keyword": {
            "type": "keyword",
            "ignore_above": 256
          }
        }
      },
      "content": {
        "type": "text",
        "fields": {
          "keyword": {
            "type": "keyword",
            "ignore_above": 256
          }
        }
      },
      "create_time": {
        "type": "date"
      },
      "id": {
        "type": "long"
      },
      "title": {
        "type": "text",
        "fields": {
          "keyword": {
            "type": "keyword",
            "ignore_above": 256
          }
        }
      },
      "update_time": {
        "type": "date"
      }
    }
  }
}

# 索引迁移
POST _reindex
{
  "source": {"index": "blog"},
  "dest": {"index": "blog_v1"}
}

# 查询测试
POST /blog_v1/_search

索引别名

# 查看别名
GET _cat/aliases


# 添加别名
POST /_aliases
{
  "actions": [
    {
      "add": {
        "index": "blog",
        "alias": "my-blog"
      }
    }
  ]
}


# 切换别名
POST /_aliases
{
  "actions": [
    {
      "add": {
        "index": "blog_v1",
        "alias": "my-blog"
      }
    },
    {
      "remove": {
        "index": "blog",
        "alias": "my-blog"
      }
    }
  ]
}

#  通过别名搜索
POST my-blog/_search

拼音处理的插件

https://github.com/medcl/elasticsearch-analysis-pinyin/releases/tag/v6.3.2

添加拼音搜索字段

# 关闭索引
POST my-blog/_close

# 设置索引支持拼音分析器
PUT my-blog/_settings
{
  "index": {
    "analysis": {
      "analyzer": {
        "pinyin_analyzer": {
          "tokenizer": "my_pinyin"
        }
      },
      "tokenizer": {
        "my_pinyin": {
          "type": "pinyin",
          "keep_first_letter": true,
          "keep_separate_first_letter": true,
          "keep_full_pinyin": true,
          "keep_original": false,
          "limit_first_letter_length": 16,
          "lowercase": true
        }
      }
    }
  }
}

# 打开索引
POST my-blog/_open

# 获取原索引mapping
GET my-blog/_mapping

# 添加字段
PUT my-blog/doc/_mapping
{
  "doc": {
    "properties": {
      "@timestamp": {
        "type": "date"
      },
      "@version": {
        "type": "text",
        "fields": {
          "keyword": {
            "type": "keyword",
            "ignore_above": 256
          }
        }
      },
      "author": {
        "type": "text",
        "fields": {
          "keyword": {
            "type": "keyword",
            "ignore_above": 256
          },
          "pinyin": {
            "type": "text",
            "analyzer": "pinyin_analyzer"
          }
        }
      },
      "content": {
        "type": "text",
        "fields": {
          "keyword": {
            "type": "keyword",
            "ignore_above": 256
          }
        }
      },
      "create_time": {
        "type": "date"
      },
      "id": {
        "type": "long"
      },
      "title": {
        "type": "text",
        "fields": {
          "keyword": {
            "type": "keyword",
            "ignore_above": 256
          }
        }
      },
      "update_time": {
        "type": "date"
      }
    }
  }
}

# 更新索引
POST my-blog/_update_by_query?conflicts=proceed

# 测试拼音搜索
POST my-blog/_search
{
  "query": {"match": {
    "author.pinyin": "libai"
  }}
}

前端显示

<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <!-- 开发环境版本,包含了有帮助的命令行警告 -->
    <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
    <!-- 引入样式 -->
    <link
      rel="stylesheet"
      href="https://unpkg.com/element-ui/lib/theme-chalk/index.css"
    />
    <!-- 引入组件库 -->
    <script src="https://unpkg.com/element-ui/lib/index.js"></script>
    <!-- axios -->
    <script src="https://unpkg.com/axios/dist/axios.min.js"></script>

    <style>
      /* 居中显示 */
      #app {
        width: 200px;
        margin: 0 auto;
        margin-top: 300px;
      }
      /* 搜索结果高亮 */
      em {
        color: red;
      }
    </style>
  </head>

  <body>
    <div id="app">
      <el-autocomplete
        v-model="state"
        :fetch-suggestions="querySearchAsync"
        placeholder="请输入内容"
        @select="handleSelect"
      >
        <!-- 自定义显示 -->
        <template slot-scope="{ item }">
          <div v-html="item.highlight.author[0]"></div>
        </template>
      </el-autocomplete>
    </div>

    <script>
      new Vue({
        el: "#app",

        data() {
          return {
            list: [],
            state: "",
          };
        },

        methods: {
          async querySearchAsync(queryString, cb) {
            // 查询地址
            const QUERY_URL = "http://localhost:9200/blog/_search";

            // 查询语句
            let query = {
              query: {
                match: {
                  author: queryString,
                },
              },
              highlight: {
                fields: { author: {} },
              },
            };

            const res = await axios.post(QUERY_URL, query);

            console.log(res.data.hits.hits);

            cb(res.data.hits.hits);
          },

          handleSelect(item) {
            console.log(item);
          },
        },
      });
    </script>
  </body>
</html>

ELASTIC 搜索开发实战-笔记