Facade

Muammo: biror amalni bajarish uchun bir necha murakkab quyi tizim bilan to’g’ri tartibda gaplashish kerak. Chaqiruvchi kod bu tafsilotlarga botib qolmasin.

G’oya: hammasini bitta soddadan interfeys - facade - ortiga yashirasiz. Chaqiruvchi bitta metod chaqiradi, facade esa ichkarida kerakli qadamlarni o’zi bajaradi.

facade.go


package main
 
import "fmt"
 
type inventory struct{}
 
func (inventory) reserve(item string) bool {
	fmt.Printf("inventar: %q zaxiraga olindi\n", item)
	return true
}
 
type payment struct{}
 
func (payment) charge(amount int) bool {
	fmt.Printf("to'lov: %d so'm yechildi\n", amount)
	return true
}
 
type shipping struct{}
 
func (shipping) send(item, address string) {
	fmt.Printf("yetkazish: %q -> %s\n", item, address)
}
 
// OrderFacade uchtasini bitta metod ortiga yashiradi.
type OrderFacade struct {
	inv  inventory
	pay  payment
	ship shipping
}
 
func (f OrderFacade) PlaceOrder(item, address string, amount int) {
	if !f.inv.reserve(item) {
		return
	}
	if !f.pay.charge(amount) {
		return
	}
	f.ship.send(item, address)
	fmt.Println("buyurtma yakunlandi")
}
 
func main() {
	facade := OrderFacade{}
	facade.PlaceOrder("Go kitobi", "Toshkent", 120000)
}


$ go run facade.go
inventar: "Go kitobi" zaxiraga olindi
to'lov: 120000 so'm yechildi
yetkazish: "Go kitobi" -> Toshkent
buyurtma yakunlandi

main uchta quyi tizimni ko’rmaydi - u faqat PlaceOrderni biladi.

Qachon: murakkab tizimga sodda “kirish eshigi” kerak bo’lganda. Go note: paket darajasida ham facade tez-tez uchraydi - net/http.Get ichida transport, ulanish, so’rovni yasashni yashiradi.

Manba / batafsil: refactoring.guru/design-patterns/facade