GoFrame 搭配 Grafana 讀取 Loki log－狼翔天地

GoFrame 搭配 Grafana 讀取 Loki log

配置 Docker

建立一資料夾(loki)

新增三檔案 loki-config.yml，promtail-local-config.yml，docker-compose.yml

以下為三檔案內容

loki-config.yml

=============================

auth_enabled: false

server:

http_listen_port: 3100

grpc_listen_port: 9096

common:

instance_addr: 127.0.0.1

path_prefix: /tmp/loki

storage:

filesystem:

chunks_directory: /tmp/loki/chunks

rules_directory: /tmp/loki/rules

replication_factor: 1

ring:

kvstore:

store: inmemory

query_range:

results_cache:

cache:

embedded_cache:

enabled: true

max_size_mb: 100

schema_config:

configs:

- from: 2020-10-24

store: boltdb-shipper

object_store: filesystem

schema: v11

index:

prefix: index_

period: 24h

ruler:

alertmanager_url: http://localhost:9093

# By default, Loki will send anonymous, but uniquely-identifiable usage and configuration

# analytics to Grafana Labs. These statistics are sent to https://stats.grafana.org/

# Statistics help us better understand how Loki is used, and they show us performance

# levels for most users. This helps us prioritize features and documentation.

# For more information on what's sent, look at

# https://github.com/grafana/loki/blob/main/pkg/usagestats/stats.go

# Refer to the buildReport method to see what goes into a report.

# If you would like to disable reporting, uncomment the following lines:

#analytics:

# reporting_enabled: false

=============================

promtail-local-config.yml

=============================

server:

http_listen_port: 9080

grpc_listen_port: 0

positions:

filename: /tmp/positions.yaml

clients:

- url: http://loki:3100/loki/api/v1/push

scrape_configs:

- job_name: system

static_configs:

- targets:

- localhost

labels:

job: varlogs

__path__: /var/log/*log

=============================

docker-compose.yml

=============================

version: "3"

networks:

loki:

services:

loki:

image: grafana/loki:2.8.0

ports:

- "3100:3100"

volumes:

- ./loki-config.yml:/etc/loki/local-config.yml

command: -config.file=/etc/loki/local-config.yml

networks:

- loki

promtail:

image: grafana/promtail:2.8.0

volumes:

- /var/log:/var/log

- ./promtail-local-config.yml:/etc/promtail/config.yml:ro

command: -config.file=/etc/promtail/config.yml

networks:

- loki

grafana:

environment:

- GF_PATHS_PROVISIONING=/etc/grafana/provisioning

- GF_AUTH_ANONYMOUS_ENABLED=true

- GF_AUTH_ANONYMOUS_ORG_ROLE=Admin

entrypoint:

- sh

- -euc

- |

mkdir -p /etc/grafana/provisioning/datasources

cat <<EOF > /etc/grafana/provisioning/datasources/ds.yaml

apiVersion: 1

datasources:

- name: Loki

type: loki

access: proxy

orgId: 1

url: http://loki:3100

basicAuth: false

isDefault: true

version: 1

editable: false

EOF

/run.sh

image: grafana/grafana:10.0.3

ports:

- "3000:3000"

networks:

- loki

=============================

啟動 Grafana

開啟 Docker Desktop

執行 docker compose up -d

設定 Grafana admin

瀏覽器開啟 http://localhost:3000/?orgId=1，點擊 Sign in

輸入預設帳/密 admin/admin, 後可以修改密碼

查詢 Loki log

重新登入後，點擊 Toggle Menu，並選擇 Explore

點擊 Label browser, 於畫面中點擊 job(1) 中的 varlogs 後，點擊 Show logs，結束設定，即可以看到結果

利用 postman 新增 log

使用 post，url 為 http://localhost:3100/loki/api/v1/push，使用 json 格式，發送以下內容

{

"streams": [

{

"stream": {

"label": "postman"

"values": [

[

"1726476194219686912", //2024-09-16 16:43:14.210 時間戳

"fizzbuzz"

]

}

]

}

若回傳結果為 204，即代表成功

查詢 postman 發送的 log

請回到網頁，點擊 code，輸入 {label="postman"}，時間區間選 Last 2 days, 即可看到結果

設定 goFrame Hook

目前分兩隻程式，一隻主要loki hook，一隻 main, 用來測試 loki hook

程式內容如下

loki.go

=============================

package loki

import (
   "bytes"
   "encoding/json"
   "fmt"
   "net/http"
   "time"

"github.com/gogf/gf/v2/os/glog"
)

const (
LOKI_LABEL = "go-demo"
LOKI_APP = "gavin-job"
)

type LokiHook struct {
   Logger *glog.Logger
   Label string
   App string
}

func (w *LokiHook) Write(p []byte) (n int, err error) {
   var (
       msg = string(p)
   )
   err = w.PostDataToLoki(msg)

return w.Logger.Write(p)
}

type LokiEntry struct {
   Streams []struct {
       Stream map[string]string `json:"stream"`
       Values [][]string `json:"values"`
   } `json:"streams"`
}

func (w *LokiHook) PostDataToLoki(msg string) error {
   stream := make(map[string]string, 0)
   //可以自由新增 key 值，方便 loki 查詢使用
   stream["label"] = w.Label
   stream["app"] = w.App //目前設定此來對應專案中 backend/app 中的應用
   valueList := make([][]string, 0)
   strTime := fmt.Sprintf("%v", time.Now().UnixNano())
   newRow := []string{strTime, msg}
   valueList = append(valueList, newRow)

   data := LokiEntry{
       Streams: []struct {
           Stream map[string]string `json:"stream"`
           Values [][]string `json:"values"`
       }{
           {
               Stream: stream,
               Values: valueList,
           },
       },
   }

   jsonData, err := json.Marshal(data)
   if err != nil {
       return err
   }

   resp, err := http.Post("http://localhost:3100/loki/api/v1/push", "application/json", bytes.NewBuffer(jsonData))
   if err != nil {
       return err
   }
   defer resp.Body.Close()

return nil
}

=============================

main.go

=============================

package main

import (
"context"

"demo/loki/loki"

   "github.com/gogf/gf/v2/frame/g"
   "github.com/gogf/gf/v2/os/gctx"
   "github.com/gogf/gf/v2/os/glog"
)

func callFun(ctx context.Context, msg string) error {
g.Log().Infof(ctx, "callFun msg:%v", msg)

return nil
}

func main() {
ctx := gctx.New()

   g.Log().SetWriter(&loki.LokiHook{
       Logger: glog.New(),
       Label: loki.LOKI_LABEL,
       App: loki.LOKI_APP,
   })

   g.Log().Infof(ctx, "run callFun")
   err := callFun(ctx, "hello, call fun test")
   if err != nil {
       g.Log().Errorf(ctx, "PostDataToLoki error:%v", err)
   } else {
       g.Log().Infof(ctx, "PostDataToLoki success")
   }

}

=============================

執行 go run main.go