Very simple example of a worker pool pattern in Golang

worker_pool.go

package main

import (
	"fmt"
	"sync"
	"time"
)

type Job chan int
type Pool chan Job

type Worker struct {
	Id int
	Pool
	JobCh Job
	WG    *sync.WaitGroup
}

func NewWorker(id int, pool Pool, wg *sync.WaitGroup) Worker {
	return Worker{
		Id:    id,
		Pool:  pool,
		JobCh: make(Job),
		WG:    wg,
	}
}

func main() {
	pool := make(Pool)
	defer close(pool)
	var wg sync.WaitGroup
	i, wc := 0, 5

	for i < wc {
		wg.Add(1)
		i++
		worker := NewWorker(i, pool, &wg)
		go worker.ReceiveData()
	}

	time.Sleep(time.Second)

	wg.Add(1)
	go SendData(wc, pool, &wg)
	
	wg.Wait()
	fmt.Println("Finished")
}

func SendData(wc int, pool Pool, wg *sync.WaitGroup) {
	defer wg.Done()
	for i := 0; i < 10; i++ {
		input := <-pool
		input <- i
		time.Sleep(500 * time.Millisecond)
	}

	for i := 0; i < wc; i++ {
		jobCh := <-pool
		close(jobCh)
	}

}

func (w *Worker) ReceiveData() {
	fmt.Printf("Worker %d is listening\n", w.Id)
	for {
		w.Pool <- w.JobCh
		v, ok := <-w.JobCh
		if ok {
			fmt.Println("Worker:", w.Id)
			fmt.Println("Recevied value:", v)
		} else {
			fmt.Println("Shutting down worker:", w.Id)
			w.WG.Done()
			return
		}
	}
}