Update the _examples/mvc/login example - add a Path property at mvc.Response and add a context.Proceed helper function

Former-commit-id: b898901fe4a324e888a6e09c93530cf7a551cf2a

_examples/mvc/login/services/user_service.go

@@ -0,0 +1,125 @@
+package services
+
+import (
+	"errors"
+
+	"github.com/kataras/iris/_examples/mvc/login/datamodels"
+	"github.com/kataras/iris/_examples/mvc/login/repositories"
+)
+
+// UserService handles CRUID operations of a user datamodel,
+// it depends on a user repository for its actions.
+// It's here to decouple the data source from the higher level compoments.
+// As a result a different repository type can be used with the same logic without any aditional changes.
+// It's an interface and it's used as interface everywhere
+// because we may need to change or try an experimental different domain logic at the future.
+type UserService interface {
+	GetAll() []datamodels.User
+	GetByID(id int64) (datamodels.User, bool)
+	GetByUsernameAndPassword(username, userPassword string) (datamodels.User, bool)
+	DeleteByID(id int64) bool
+
+	Update(id int64, user datamodels.User) (datamodels.User, error)
+	UpdatePassword(id int64, newPassword string) (datamodels.User, error)
+	UpdateUsername(id int64, newUsername string) (datamodels.User, error)
+
+	Create(userPassword string, user datamodels.User) (datamodels.User, error)
+}
+
+// NewUserService returns the default user service.
+func NewUserService(repo repositories.UserRepository) UserService {
+	return &userService{
+		repo: repo,
+	}
+}
+
+type userService struct {
+	repo repositories.UserRepository
+}
+
+// GetAll returns all users.
+func (s *userService) GetAll() []datamodels.User {
+	return s.repo.SelectMany(func(_ datamodels.User) bool {
+		return true
+	}, -1)
+}
+
+// GetByID returns a user based on its id.
+func (s *userService) GetByID(id int64) (datamodels.User, bool) {
+	return s.repo.Select(func(m datamodels.User) bool {
+		return m.ID == id
+	})
+}
+
+// GetByUsernameAndPassword returns a user based on its username and passowrd,
+// used for authentication.
+func (s *userService) GetByUsernameAndPassword(username, userPassword string) (datamodels.User, bool) {
+	if username == "" || userPassword == "" {
+		return datamodels.User{}, false
+	}
+
+	return s.repo.Select(func(m datamodels.User) bool {
+		if m.Username == username {
+			hashed := m.HashedPassword
+			if ok, _ := datamodels.ValidatePassword(userPassword, hashed); ok {
+				return true
+			}
+		}
+		return false
+	})
+}
+
+// Update updates every field from an existing User,
+// it's not safe to be used via public API,
+// however we will use it on the web/controllers/user_controller.go#PutBy
+// in order to show you how it works.
+func (s *userService) Update(id int64, user datamodels.User) (datamodels.User, error) {
+	user.ID = id
+	return s.repo.InsertOrUpdate(user)
+}
+
+// UpdatePassword updates a user's password.
+func (s *userService) UpdatePassword(id int64, newPassword string) (datamodels.User, error) {
+	// update the user and return it.
+	hashed, err := datamodels.GeneratePassword(newPassword)
+	if err != nil {
+		return datamodels.User{}, err
+	}
+
+	return s.Update(id, datamodels.User{
+		HashedPassword: hashed,
+	})
+}
+
+// UpdateUsername updates a user's username.
+func (s *userService) UpdateUsername(id int64, newUsername string) (datamodels.User, error) {
+	return s.Update(id, datamodels.User{
+		Username: newUsername,
+	})
+}
+
+// Create inserts a new User,
+// the userPassword is the client-typed password
+// it will be hashed before the insertion to our repository.
+func (s *userService) Create(userPassword string, user datamodels.User) (datamodels.User, error) {
+	if user.ID > 0 || userPassword == "" || user.Firstname == "" || user.Username == "" {
+		return datamodels.User{}, errors.New("unable to create this user")
+	}
+
+	hashed, err := datamodels.GeneratePassword(userPassword)
+	if err != nil {
+		return datamodels.User{}, err
+	}
+	user.HashedPassword = hashed
+
+	return s.repo.InsertOrUpdate(user)
+}
+
+// DeleteByID deletes a user by its id.
+//
+// Returns true if deleted otherwise false.
+func (s *userService) DeleteByID(id int64) bool {
+	return s.repo.Delete(func(m datamodels.User) bool {
+		return m.ID == id
+	}, 1)
+}