v8go_concurrency.go

package main

import (
	"fmt"
	"strconv"
	"time"
  
	v8 "rogchap.com/v8go"
)

func concurrency(ctx context.Context, workers int, c chan string, d chan string) {
	for i := 0; i < workers; i++ {
		i := i
		go func() {
			fmt.Println("starting")
			iso := v8.NewIsolate()

			v8Ctx := v8.NewContext(iso)
			for {
				select {
				case s := <-c:
					fmt.Println("received", s, "from worker", i)
					v, err := v8Ctx.RunScript(s, "")
					if err != nil {
						panic(err)
					}
					d <- v.String() + "from strong" + strconv.Itoa(i)
					iso.Dispose()
					iso = v8.NewIsolate()
					v8Ctx = v8.NewContext(iso)
				case <-ctx.Done():
					fmt.Println("received done", ctx.Err())
					return
				}
			}
		}()
	}
}

func main() {
	workers := 4
	c := make(chan string, workers)
	d := make(chan string, workers)

	ctx, cancelFunc := context.WithCancel(context.Background())
	concurrency(ctx, workers, c, d)
	go func() {
		for {
			c <- "100+11"
			time.Sleep(time.Second)
		}
	}()
	go func() {
		time.Sleep(time.Second * 4)
		cancelFunc()
		close(d)
		fmt.Println("called cancel")
	}()
	for e := range d {
		fmt.Println("result", e)
	}
	fmt.Println("ending:", ctx.Err())
}