Delay Queue

Delay Queue

Overview

With regard to extended tasks, there are many scenarios in which the return of stocks is automatically closed without payment after 20 minutes.

go-queue implements the time queue dq, in addition to providing kafka message queue kq.The bottom layer of the go-queue is used for the beanstalkd.

Config

type (
    Beanstalk struct {
        Endpoint string
        Tube     string
    }

    DqConf struct {
        Beanstalks []Beanstalk
        Redis      redis.RedisConf
    }
)

Beantalks: multiple Beanstalk node configurations
Redis：redis configuration, mainly using Setnx here

pusher using dq in go-zero

First pull go-queue dependencies in the project

$ go get github.com/zeromicro/go-queue@latest

Add current dq configuration information to the etc/xxx.yaml configuration file

Name: dq
Host: 0.0.0.0
Port: 8888

......

DqConf:
  Beanstalks:
    - Endpoint: 127.0.0.1:7771
      Tube: tube1
    - Endpoint: 127.0.0.1:7772
      Tube: tube2

Define configuration of go mapping in config.go under internal/config

type Config struct {
    ......
    DqConf struct {
        Brokers []string
        Topic   string
    }
}

Initialize a penchant dq client in svc/serviceContext.go

type ServiceContext struct {
    Config         config.Config
  .....
    DqPusherClient dq.Producer
}

func NewServiceContext(c config.Config) *ServiceContext {
    return &ServiceContext{
        Config:         c,
    .....
        DqPusherClient: dq.NewProducer(c.DqConf.Beanstalks),
    }
}

Write business logic in logic, using go-queue dq client to send messages to beanstalk

.......
func (l *PusherLogic) Pusher() error {

  msg := "data"

    // 1、5s后执行
    deplayResp, err := l.svcCtx.DqPusherClient.Delay([]byte(msg), time.Second*5)
    if err != nil {
        logx.Errorf("error from DqPusherClient Delay err : %v", err)
    }
    logx.Infof("resp : %s", deplayResp) // fmt.Sprintf("%s/%s/%d", p.endpoint, p.tube, id)

    // 2、在某个指定时间执行
    atResp, err := l.svcCtx.DqPusherClient.At([]byte(msg), time.Now())
    if err != nil {
        logx.Errorf("error from DqPusherClient Delay err : %v", err)
    }
    logx.Infof("resp : %s", atResp) // fmt.Sprintf("%s/%s/%d", p.endpoint, p.tube, id)

  return nil
}

Use dq consumer consumer in go-zero

First pull go-queue dependencies in the project

$ go get github.com/zeromicro/go-queue@latest

Add current kafka configuration information to the etc/xxx.yaml configuration file

Name: dq
Host: 0.0.0.0
Port: 8889

.....

#dq
DqConf:
  Beanstalks:
    - Endpoint: 127.0.0.1:7771
      Tube: tube1
    - Endpoint: 127.0.0.1:7772
      Tube: tube2
  Redis:
    Host: 127.0.0.1:6379
    Type: node

Define configuration of go mapping in config.go under internal/config

package config

import (
    "github.com/zeromicro/go-queue/dq"
    "github.com/zeromicro/go-zero/rest"
)

type Config struct {
    rest.RestConf
    .......
    DqConf dq.DqConf
}

Initialize consumer dq client in svc/serviceContext.go

type ServiceContext struct {
    Config         config.Config
  .....
    DqConsumer dq.Consumer
}

func NewServiceContext(c config.Config) *ServiceContext {
    return &ServiceContext{
        Config:         c,
    .....
        DqConsumer: dq.NewConsumer(c.DqConf),
    }
}

logic 中消费延时消息

func (l *PusherLogic) Consumer() error {
  l.svcCtx.DqConsumer.Consume(func(body []byte) {
        logx.Infof("consumer job  %s \n", string(body))
    })
}

Write in the end, the beanstalk is not reliant on redis, but go-queue is the better we want to prevent repeated consumption in a short period of time, using redis Setnx to allow us to filter spent messages within a short period of time

References

Beanstalkd Introduction and Installation