Very simples example using Goroutines, Context and WaitGroup

goroutines_context.go

package main

import (
	"fmt"
	"sync"
	"math/rand"
	"time"
	"context"
)

func consumer(ctx context.Context, wg *sync.WaitGroup, ch chan string) {
	for {
		select {
		case <-ctx.Done():
			fmt.Println("Context has been canceled. Exiting consumer.")
			wg.Done()
			return	
		case v := <-ch:
			fmt.Printf("I've received a %s.\n", v)
			time.Sleep(500*time.Millisecond)
		}
	}
}

func producer(ctx context.Context, wg *sync.WaitGroup, ch chan string) {
	items := []string{"banana", "strawberry", "cranberry", "potato"}
	for {
		select {
		case <-ctx.Done():
			fmt.Println("Context has been canceled. Exiting producer.")
			wg.Done()
			return	
		default:
			index := rand.Intn(len(items))
			ch <-items[index]
			time.Sleep(500*time.Millisecond)
		}
	}
}

func main() {
  // In this examples every producer should stop before consumer
  // I'm yet a beginner programming go, any critic is welcome
	var wg, pwg sync.WaitGroup
	ctx, _ := context.WithTimeout(context.Background(), 5*time.Second)
	cctx, cancel := context.WithCancel(context.Background())
	ch := make(chan string)
	pwg.Add(1)
	go consumer(cctx, &pwg, ch)
	for i := 0; i < 10; i ++ {
		wg.Add(1)
		go producer(ctx, &wg, ch)
	}
	wg.Wait()
	fmt.Println("Canceling consumer.")
	cancel()
	pwg.Wait()
	fmt.Println("Exiting program!")
}