【搜索】elasticsearch

• 安装

  npm i -S @elastic/elasticsearch
  

  • 最新版本 7.16.0
    • 要求node版本要在12.0以上

• 在lib/db文件夹下，新建elastic_core.js文件，进行封装

  import { Client } from '@elastic/elasticsearch';
  import config from "config";
  import { Log } from "../utils/api_log.js";
  const log = new Log("elastic_core");
  
  const client = new Client({ node: config.get('elasticConfig.url') })
  
  client.on('error', (err) =>{
      log.error('elastic client err:', err);
  })
  
  const hitsFilter = (hit, fieldsArray) => {
      const filtered = {};
      filtered.score = hit._score;
      fieldsArray.forEach((field) => {
          if (hit._source[field]) {
              filtered[field] = hit._source[field];
          }
      });
      return filtered;
  }
  
  export const elasticSearch = async (obj, fieldsArray) => {
      const { body } = await client.search(obj);
      return {
          total: body.hits.total.value,
          hits: body.hits.hits.map((hit)=>{
              return hitsFilter(hit, fieldsArray);
          })
      };
  }
  
  //这里可添加下面的测试代码,只运行一次即可生成测试数据，后面要注释掉
  

  • 需要配置url，默认是http://127.0.0.1:9200

• 封装后在路由中使用

  import { elasticSearch } from "../../../db/elastic_core.js";
  

  router.get("/test_elastic", async ctx => {
      log.debug("== get test_elastic")
      const fieldsArray = ["character", "quote"];
      const result = await elasticSearch({
          index: 'game-of-thrones',
          body: {
              query: {
                  match: { quote: 'winter' }
              }
          }
      }, fieldsArray)
      ctx.body = result;
  })
  

• 测试代码

  await client.index({
      index: 'game-of-thrones',
      body: {
          character: 'Ned Stark',
          quote: 'Winter is coming.'
      }
  })
  
  await client.index({
      index: 'game-of-thrones',
      body: {
          character: 'Daenerys Targaryen',
          quote: 'I am the blood of the dragon.'
      }
  })
  
  await client.index({
      index: 'game-of-thrones',
      body: {
          character: 'Tyrion Lannister',
          quote: 'A mind needs books like a sword needs a whetstone.'
      }
  })
  
  await client.indices.refresh({ index: 'game-of-thrones' })