articles-api/service/user/user.go

package user

import (
	"net/http"

	"git.xdrm.io/go/aicra"
	"git.xdrm.io/go/aicra/api"
	"git.xdrm.io/go/tiny-url-ex/service/model"
	"github.com/jinzhu/gorm"
)

// Service to manage users
type Service struct {
	DB *gorm.DB
}

// Wire services to their paths
func (s Service) Wire(server *aicra.Server) error {
	if !s.DB.HasTable(&model.User{}) {
		s.DB.CreateTable(&model.User{})
	}

	if err := server.Handle(http.MethodGet, "/user/{id}", s.getUserByID); err != nil {
		return err
	}
	if err := server.Handle(http.MethodGet, "/users", s.getAllUsers); err != nil {
		return err
	}
	if err := server.Handle(http.MethodPost, "/user", s.createUser); err != nil {
		return err
	}
	if err := server.Handle(http.MethodPut, "/user/{id}", s.updateUser); err != nil {
		return err
	}
	if err := server.Handle(http.MethodDelete, "/user/{id}", s.deleteUser); err != nil {
		return err
	}
	return nil
}

type userList struct {
	Users []model.User
}

func (s Service) getAllUsers() (*userList, api.Error) {
	users := userList{}
	s.DB.Find(&users.Users)
	return &users, api.ErrorSuccess
}

func (s Service) getUserByID(param struct{ ID uint }) (*model.User, api.Error) {
	var user model.User
	if s.DB.First(&user, param.ID).RecordNotFound() {
		return nil, api.ErrorNoMatchFound
	}

	return &user, api.ErrorSuccess
}

type createRequest struct {
	Username  string
	Firstname string
	Lastname  string
}

func (s Service) createUser(param createRequest) (*model.User, api.Error) {
	user := model.User{
		Username:  param.Username,
		Firstname: param.Firstname,
		Lastname:  param.Lastname,
	}

	s.DB.Create(&user)
	if s.DB.Last(&user).RecordNotFound() {
		return nil, api.ErrorNoMatchFound
	}

	return &user, api.ErrorSuccess
}

type updateRequest struct {
	ID        uint
	Username  *string
	Firstname *string
	Lastname  *string
}

func (s Service) updateUser(param updateRequest) (*model.User, api.Error) {
	var user model.User
	if s.DB.First(&user, param.ID).RecordNotFound() {
		return nil, api.ErrorNoMatchFound
	}

	// override with updated values
	if param.Username != nil {
		user.Username = *param.Username
	}
	if param.Firstname != nil {
		user.Firstname = *param.Firstname
	}
	if param.Lastname != nil {
		user.Lastname = *param.Lastname
	}

	// update
	if s.DB.Save(&user).RowsAffected < 1 {
		return nil, api.ErrorFailure
	}

	return &user, api.ErrorSuccess
}

func (s Service) deleteUser(param struct{ ID uint }) api.Error {
	user := model.User{
		ID: param.ID,
	}
	s.DB.Delete(&user)
	return api.ErrorSuccess
}