machine golang 并发工具包使用
以前有简单介绍过machine，以下是一个简单的试用（集成了gorunine 以及cron任务）
项目结构
- 代码结构
├── docker-compose.yaml
├── go.mod
├── go.sum
├── main.go
├── pkg
│ ├── filesync.go
│ └── updatefile.go
└── sql
└── init.sql
- 代码说明
以上是一个简单的基于machine发布订阅以及定时任务能力实现的一个同时数据写入db - main.go
基于machine实现goruntine 的管理，支持PanicRecover,发布订阅以及定时任务
package main
import (
"context"
"demoapp/pkg"
"fmt"
"log"
"net/http"
_ "net/http/pprof"
"time"
"github.com/autom8ter/machine"
_ "github.com/go-sql-driver/mysql"
"github.com/jmoiron/sqlx"
)
func main() {
db, err := sqlx.Connect("mysql", "root:appdemo@tcp(127.0.0.1:3306)/app?charset=utf8")
if err != nil {
log.Fatalln(err)
}
defer db.Close()
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
m := machine.New(ctx, machine.WithTags("demoapp"), machine.WithMaxRoutines(10),
machine.WithMiddlewares(machine.PanicRecover()))
m.Go(func(routine machine.Routine) {
fmt.Printf("%v | stats = %s\n", routine.PID(), routine.Machine().Stats().Tags)
// publish message to channel
sameFiles, err := pkg.FetchSameFile(db)
if err != nil {
log.Println("fetch sameFiles error", err.Error())
routine.Publish("demo", err)
}
if len(sameFiles)%2 == 0 {
// normal datas
routine.Publish("demo", sameFiles)
} else {
routine.Publish("demo", map[string]interface{}{
"name": "dlaong",
})
}
// 支持定时任务以及tag 的中间件扩展
}, machine.GoWithTags("publish"),
machine.GoWithPID("demoapp"),
machine.GoWithMiddlewares(
// run every second until context cancels
machine.Cron(time.NewTicker(1*time.Second)),
))
m.Go(func(routine machine.Routine) {
fmt.Printf("one: %v | stats = %s\n", routine.PID(), routine.Machine().Stats().Tags)
// 订阅
routine.Subscribe("demo", func(msg interface{}) {
switch msg.(type) {
case error:
log.Println("print error message")
case []pkg.SameFile:
pkg.Update2(db, msg.([]pkg.SameFile))
default:
log.Println("don't know", msg)
}
})
})
m.Go(func(routine machine.Routine) {
// http seerver 同时进行消息发布
http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
routine.Publish("demo", map[string]interface{}{
"name": "dlaong",
"type": "from web server",
})
fmt.Fprintf(w, "%s userinfo", "dalong")
})
http.ListenAndServe(":8080", nil)
})
m.Wait()
}
db 操作，很简单，主要是基于sqlx进行的mysql 操作,参考代码
filesync.go:
package pkg
import "github.com/jmoiron/sqlx"
// User for db user
type User struct {
// UID
UID int `json:"uid" db:"uid"`
}
// SameFile for db SameFile
type SameFile struct {
// UID
Parent int64 `json:"parent" db:"parent"`
Name string `json:"name" db:"name"`
}
// FetchUser fetch users
func FetchUser(con *sqlx.DB) (users []User, err error) {
selectSQL := `select distinct uid from user`
myusers := []User{}
err = con.Select(&myusers, selectSQL)
if err != nil {
return nil, err
}
return myusers, nil
}
// FetchSameFile fetch samefile
func FetchSameFile(con *sqlx.DB) (sameFiles []SameFile, err error) {
selectSQL := `select distinct parent,name from file where size >0 group by parent,name having count(*)>1`
mysameFile := []SameFile{}
err = con.Select(&mysameFile, selectSQL)
if err != nil {
return nil, err
}
return mysameFile, nil
}
updatefile.go
package pkg
import (
"log"
"github.com/jmoiron/sqlx"
)
// Update2 update samefile
func Update2(con *sqlx.DB, sameFiles []SameFile) {
log.Println("fetch same file counts:", len(sameFiles))
for _, SameFile := range sameFiles {
updateSQL := `insert into log2(id,content) values(:id,:content)`
log.Println("name,parent", SameFile.Name, SameFile.Parent)
result, err := con.NamedExec(updateSQL, map[string]interface{}{
"id": SameFile.Parent,
"content": SameFile.Name,
})
if err != nil {
log.Println("some wrong:", err.Error())
}
effectCount, err := result.RowsAffected()
if err != nil {
log.Println("exec wrong:", err.Error())
}
log.Println("exec result:", effectCount)
}
}
- 参考火焰图（结合系统查看）
可以方便分析goruntine 
说明
以上代码比较简单，同时也集成了pprof，我们可以观测goruntine的 行为
参考资料
https://github.com/autom8ter/machine
