starbucks.go --> example

starbucks.go

package main

import (
	"fmt"
	"time"
)


type Barista struct {
	name   string
	orders chan string // channel of orders
	drinks chan string // channel of drinks
}

var drinks = map[string]int{
	"Flat white": 2,
	"Filter":     4,
}

func (b Barista) makeDrink(name string) {
	fmt.Println(b.name, "making", name)
	time.Sleep(time.Second * time.Duration(drinks[name]))
}

func (b Barista) waitForOrders() {
	for {
		fmt.Println(b.name, "waiting for orders")
		drink := <-b.orders
		b.makeDrink(drink)
		b.drinks <- drink
	}
}

func NewBarista(name string, orders chan string, drinks chan string) Barista {
	b := Barista{name, orders, drinks}
	go b.waitForOrders()
	return b
}

type Customer struct {
	name   string
	orders chan string
	drinks chan string
}

func (c Customer) collectDrink() {
	fmt.Println(c.name, "waiting to collect drink")
	drink := <-c.drinks
	fmt.Println(c.name, "collected", drink)
}
func (c Customer) order(drink string) {
	fmt.Println(c.name, "ordered a", drink)
	c.orders <- drink
	c.collectDrink()
}
func NewCustomer(name string, orders chan string, drinks chan string) Customer {
	c := Customer{name, orders, drinks}
	return c
}



func main() {
	orders := make(chan string)
	drinks := make(chan string)

	NewBarista("Bas", orders, drinks)
	NewBarista("Martin", orders, drinks)


	c1 := NewCustomer("Arno", orders, drinks)
	c2 := NewCustomer("David", orders, drinks)

	c1.order("Filter")
	c2.order("Flat white")

	time.Sleep(time.Second * 10)
}