Limit number of goroutines reading from channel

main.go

package main

import (
	"fmt"
	"os"
	"os/signal"
	"sync"
)

var wg sync.WaitGroup
var osInterrupt bool

const maxThreads = 5 // Number of maximum goroutines

func main() {

	c := make(chan os.Signal, 1)
	signal.Notify(c, os.Interrupt)

	q := make(chan string)
	wg.Add(1)
	go produce(q)

	for i := 0; i < maxThreads; i++ {
		wg.Add(1)
		go consume(q)
	}

	go func() {
		<-c
		fmt.Println("Interrupt recvd")
		osInterrupt = true
	}()
	wg.Wait()
	fmt.Println("Graceful exit")
}

func produce(q chan string) {
	fmt.Println("Production started")
	i := 0
	for {
		if osInterrupt { //TODO: Is this thread-safe
			close(q)
			break
		}
		q <- fmt.Sprintf("%d", i)
		i++
	}
	fmt.Println("Production stopped")
	wg.Done()
}

func consume(q chan string) {
	fmt.Println("Consumption started")
	for {
		a, ok := <-q
		if !ok { // channel has been closed
			wg.Done()
			fmt.Println("Consumption stopped")
			return
		}
		fmt.Println(a)
		// time.Sleep(2 * time.Second)
	}
}