go-sample-webpage/pkg/user/userclient.go

package user

import (
	"encoding/base64"
	"errors"
	"fmt"
	"math/rand"
)

type UserClient interface {
	register(username, password, email string) (bool, error)
	login(username, password string, requiredMailValidation bool) (bool, error)
	getMailValidationToken(email string, forceRecreate bool,) (string, error)
}

type UserClientMemory struct {
	users map[string]string
}

var u *UserClientMemory

func GetUserMemmoryClient() *UserClientMemory {
	if u == nil {
		uc := UserClientMemory{}
		uc.users = make(map[string]string)
		uc.users["admin"]="password"
		u = &uc
	}

	return u
}

func (uc *UserClientMemory) register(username, password, email string) (bool, error) {
	if _, ok := uc.users[username]; ok {
		return false, errors.New("Username already used")
	}

	uc.users[username] = password
	return true, nil
}

func (uc UserClientMemory) login(username, password string, requiredMailValidation bool) (bool, error) {
	if requiredMailValidation == true {
		return false, errors.New("In memmory User Client cant validate email addresses")
	}
	if val, ok := uc.users[username]; ok {
		fmt.Println("Login for valide user")
		if val == password {
			return true, nil
		}
	} else {
		fmt.Printf("User %v not found", username)
	}

	return false, nil
}

func (uc UserClientMemory) getMailValidationToken(email string, forceRecreate bool) (string, error) {
	token := randomString(35)
	token = fmt.Sprintf("%v/%v", base64.StdEncoding.EncodeToString([]byte(email)), token)
	return token, nil
}


func randomString(n int) string {
	var letters = []byte("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")
	b := make([]byte, n)
	for i := range b {
		b[i] = letters[rand.Intn(len(letters))]
	}
	return string(b)
}