long_poller_go/poller.go

package long_poller_go

import (
	"context"
	"google.golang.org/grpc"
	"loafle.com/overflow/cron_go"
	"log"
	"sync"

	pb "loafle.com/overflow/crawler_go/grpc" //temp
)

var (
	POLLING_ID       = "OVERFLOW_LONG_POLLING"
	DEFAULT_INTERVAL = uint64(3)
	API_SERVER_ADDR  = "127.0.0.1:50052"
)

type LongPoller struct {
	once    sync.Once
	runStat chan bool
	wg      sync.WaitGroup
}

func (p *LongPoller) Start() {
	p.once.Do(func() {
		p.wg.Add(1)
		p.startPolling()
		p.wg.Wait()
	})
}

func (p *LongPoller) startPolling() {
	cr := &cron.Cron{}
	p.runStat = cr.Start()
	cr.AddTask(POLLING_ID, DEFAULT_INTERVAL).Invoke(p.polling, agentIdentifier())
}

func (p *LongPoller) Stop() {
	p.runStat <- false
	p.wg.Done()
}

func (p *LongPoller) polling(agentId string) {

	conn, err := grpc.Dial(API_SERVER_ADDR, grpc.WithInsecure())
	if err != nil {
		log.Println(err)
		return
	}
	defer conn.Close()

	//todo temporary
	client := pb.NewStatusClient(conn)
	out, err := client.Status(context.Background(), &pb.Empty{})
	if err != nil {
		log.Println(err)
	}

	p.dispatchNotify(out)
}

func (p *LongPoller) dispatchNotify(result interface{}) {
	log.Printf("Polling result - %s ", result)
}

func agentIdentifier() string {
	//todo
	return "agent000001"
}