https://mrizkimaulidan.vercel.app/posts/2024/interface-untuk-penggantian-data-source/

inmemory.go

package main

type InMemory struct {
	//
}

var usersFromInMemory = []map[string]any{
	{
		"id":   1,
		"name": "John Doe",
		"age":  21,
	},
	{
		"id":   2,
		"name": "Elisa Doe",
		"age":  35,
	},
}

func (r InMemory) GetAll() []map[string]any {
	return usersFromInMemory
}

func (r InMemory) Find(id int) map[string]any {
	for _, user := range usersFromInMemory {
		if user["id"] == id {
			return user
		}
	}
	return nil
}

func NewInMemory() Storage {
	return InMemory{}
}

main.go

package main

import "fmt"

func main() {
	// storage := NewRedis()
	// storage := NewInMemory()
	// storage := NewMongoDB()
	storage := NewPostgreSQL()

	fmt.Println(storage.GetAll())
	fmt.Println(storage.Find(1))
}

mongodb.go

package main

type MongoDB struct {
	//
}

var usersFromMongoDB = []map[string]any{
	{
		"id":   1,
		"name": "Mace Windu",
		"age":  53,
	},
	{
		"id":   2,
		"name": "Jabba The Hut",
		"age":  650,
	},
}

func (r MongoDB) GetAll() []map[string]any {
	return usersFromMongoDB
}

func (r MongoDB) Find(id int) map[string]any {
	for _, user := range usersFromMongoDB {
		if user["id"] == id {
			return user
		}
	}
	return nil
}

func NewMongoDB() Storage {
	return MongoDB{}
}

postgresql.go

package main

type PostgreSQL struct {
	//
}

var usersFromPostgreSQL = []map[string]any{
	//
}

func (r PostgreSQL) GetAll() []map[string]any {
	return nil
}

func (r PostgreSQL) Find(id int) map[string]any {
	return nil
}

func NewPostgreSQL() Storage {
	return PostgreSQL{}
}

redis.go

package main

type Redis struct {
	//
}

var usersFromRedis = []map[string]any{
	{
		"id":   1,
		"name": "John Doe",
		"age":  21,
	},
	{
		"id":   2,
		"name": "Elisa Doe",
		"age":  35,
	},
}

func (r Redis) GetAll() []map[string]any {
	return usersFromRedis
}

func (r Redis) Find(id int) map[string]any {
	for _, user := range usersFromRedis {
		if user["id"] == id {
			return user
		}
	}
	return nil
}

func NewRedis() Storage {
	return Redis{}
}

storage.go

package main

type Storage interface {
	GetAll() []map[string]any
	Find(id int) map[string]any
}