//Package 最最基本的用法
package main

import (
	"fmt"
	"log"
	"time"

	client "github.com/influxdata/influxdb1-client/v2"
)

// influxdb demo

func connInflux() client.Client {
	cli, err := client.NewHTTPClient(client.HTTPConfig{
		Addr:     "http://127.0.0.1:8086",
		Username: "admin",
		Password: "",
	})
	if err != nil {
		log.Fatal(err)
	}
	return cli
}

// query
func queryDB(cli client.Client, cmd string) (res []client.Result, err error) {
	q := client.Query{
		Command:  cmd,
		Database: "test",
	}
	if response, err := cli.Query(q); err == nil {
		if response.Error() != nil {
			return res, response.Error()
		}
		res = response.Results
	} else {
		return res, err
	}
	return res, nil
}

// insert
func writesPoints(cli client.Client) {
	bp, err := client.NewBatchPoints(client.BatchPointsConfig{
		Database:  "test",
		Precision: "s", //精度，默认ns
	})
	if err != nil {
		log.Fatal(err)
	}
	tags := map[string]string{"cpu": "ih-cpu"}
	fields := map[string]interface{}{
		"idle":   201.1,
		"system": 43.3,
		"user":   86.6,
	}

	pt, err := client.NewPoint("cpu_usage", tags, fields, time.Now())
	if err != nil {
		log.Fatal(err)
	}
	bp.AddPoint(pt)
	err = cli.Write(bp)
	if err != nil {
		log.Fatal(err)
	}
	log.Println("insert success")
}

func main() {
	conn := connInflux()
	fmt.Println(conn)

	// insert
	writesPoints(conn)

	// 获取10条数据并展示
	qs := fmt.Sprintf("SELECT * FROM %s LIMIT %d", "cpu_usage", 10)
	res, err := queryDB(conn, qs)
	if err != nil {
		log.Fatal(err)
	}

	for _, row := range res[0].Series[0].Values {
		for j, value := range row {
			log.Printf("j:%d value:%v\n", j, value)
		}
	}
}