influxDB学习总结

1.安装

请参考http://www.cnblogs.com/zhja/p/5996191.html，

安装完毕运行influxd，http://域名:8083为控制台界面；http://域名:8086为api地址；运行influx进入命令行模式。

2.go操作influxdb
　　1）利用influxdb的client，github地址：github.com/influxdata/influxdb/client/v2
　　2）创建用户和授权

create user zhja with password 'zhjazhja'
grant all privileges to zhja

　　3）创建数据库

create database nfdump

　　4）链接influxdb

package main

import (
    "fmt"
    "log"

    "github.com/influxdata/influxdb/client/v2"
)

const (
    MyDB = "nfdump" //数据库名
    username = "zhja" //用户名
    password = "zhjazhja" //密码
)

func main(){
    //链接数据库
    c, err := client.NewHTTPClient(client.HTTPConfig{
        Addr: "http://192.168.210.130:8086",
        Username: username,
        Password: password,
    })

    if err != nil {
        log.Fatalln("Error: ", err)
    }

    fmt.Println(c)
}            

执行结果：

5）influxdb Measurements（查看详细介绍）
6）批量插入数据

package main

import (
"fmt"
"log"
"time"
"math/rand"

"github.com/influxdata/influxdb/client/v2"
)

const (
    MyDB = "nfdump" //数据库名
    username = "zhja" //用户名
    password = "zhjazhja" //密码
)

func main(){
    //链接数据库
    c, err := client.NewHTTPClient(client.HTTPConfig{
        Addr: "http://192.168.210.130:8086",
        Username: username,
        Password: password,
    })

    if err != nil {
        log.Fatalln("Error: ", err)
    }

    writePoints(c, MyDB)
}

func writePoints(c client.Client, MyDB string) {
    sampleSize := 1000
    rand.Seed(42)

    bp, _ := client.NewBatchPoints(client.BatchPointsConfig{
        Database: MyDB,
        Precision: "us",
    })

    for i := 0; i < sampleSize; i++ {
        regions := []string{"us-west1", "us-west2", "us-west3", "us-east1"}
        tags := map[string]string{
            "cpu": "cpu-total",
            "host": fmt.Sprintf("host%d", rand.Intn(1000)),
            "region": regions[rand.Intn(len(regions))],
        }

        idle := rand.Float64() * 100.0
        fields := map[string]interface{}{
            "idle": idle,
            "busy": 100.0 - idle,
        }

        pt, err := client.NewPoint("cpu_usage", tags, fields, time.Now())
        if err != nil {
            log.Fatalln("Error: ", err)
        }

        bp.AddPoint(pt)
    }

    err := c.Write(bp)
    if err != nil {
        log.Fatal(err)
    }
}        

执行结果：

7）利用sql查询数据，利用上面的数据

package main

import (
    "fmt"
    "log"
    "time"
    "encoding/json"

    "github.com/influxdata/influxdb/client/v2"
)

const (
    MyDB = "nfdump"         //数据库名
    username = "zhja"       //用户名
    password = "zhjazhja"   //密码
    MyMeasurement = "cpu_usage"
)

func main(){
    //链接数据库
    c, err := client.NewHTTPClient(client.HTTPConfig{
        Addr: "http://192.168.210.130:8086",
        Username: username,
        Password: password,
    })

    if err != nil {
        log.Fatalln("Error: ", err)
    }

    //创建数据库
    _, err := queryDB(c, fmt.Sprintf("CREATE DATABASE %s", MyDB))
    if err != nil {
        log.Fatal(err)
    }

    //获取总数
    q := fmt.Sprintf("SELECT count(%s) FROM %s", "*", MyMeasurement)
    res, err := queryDB(c, q)
    if err != nil {
        log.Fatal(err)
    }
    count := res[0].Series[0].Values[0][1]
    log.Printf("Found a total of %v records\n", count)

    //获取10条数据并展示
    qs := fmt.Sprintf("SELECT * FROM %s LIMIT %d", MyMeasurement, 20)
    res, err = queryDB(c, qs)
    if err != nil {
        log.Fatal(err)
    }

    for i, row := range res[0].Series[0].Values {
        t, err := time.Parse(time.RFC3339, row[0].(string))
        if err != nil {
            log.Fatal(err)
        }
        //fmt.Println(reflect.TypeOf(row[1]))
        val := row[1].(json.Number)
        log.Printf("[%2d] %s: %s\n", i, t.Format(time.Stamp), val)
    }
}

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

执行结果：