package main

import (
	"context"
	"encoding/json"
	"fmt"
	"github.com/olivere/elastic/v7"
	"log"
	"os"
	"time"
)

// 深度分页
// https://www.cnblogs.com/hello-shf/p/11543453.html

var client elastic.Client

func main() {
	var host = "http://10.10.14.188:9200/"
	esClient, err := elastic.NewClient(
		elastic.SetURL(host),
		elastic.SetSniff(false),
		elastic.SetHealthcheckInterval(10*time.Second),
		elastic.SetGzip(true),
		elastic.SetErrorLog(log.New(os.Stderr, "ELASTIC ", log.LstdFlags)),
		elastic.SetInfoLog(log.New(os.Stdout, "", log.LstdFlags)))

	if err != nil {
		panic(err)
	}

	//取所有
	CTX := context.Background()
	result, err := esClient.Scroll().Index("user_teacher").Size(10).Do(CTX)
	if err != nil {
		fmt.Println(err.Error())
	}
	//第一次的结果集
	for i := range result.Hits.Hits {
		resByte, _ := json.Marshal(result.Hits.Hits[i])
		resStr := string(resByte)
		fmt.Println(resStr)
	}
	//继续用的 scoll_id
	scrollId := result.ScrollId

	//第一次命中的个数
	var nowCount = int64(len(result.Hits.Hits))
	//总的命中个数
	allCount := result.TotalHits()

	//开始循环
	for {
		fmt.Println(nowCount)
		//如果还有数据没有获取
		if allCount > nowCount {
			result, err = esClient.Scroll().ScrollId(scrollId).Do(CTX)
			scrollId = result.ScrollId
			nowCount += int64(len(result.Hits.Hits))

			for i := range result.Hits.Hits {
				resByte, _ := json.Marshal(result.Hits.Hits[i])
				resStr := string(resByte)
				fmt.Println(resStr)
			}
		} else {
			//没有数据了
			break
		}
	}
}