feat: migrate auth module to modular domain pattern

internal/app/app.go

@@ -2,6 +2,7 @@ package app
 
 import (
 	"mal/internal/database"
+	"mal/internal/auth"
 	"mal/internal/server"
 	"mal/internal/templates"
 
@@ -14,6 +15,7 @@ func NewApp() *fx.App {
 	return fx.New(
 		database.Module,
 		jikan.Module,
+		auth.Module,
 		templates.Module,
 		server.Module,
 		fx.Decorate(func(r *templates.Renderer) render.HTMLRender {

internal/auth/handler/handler.go

@@ -0,0 +1,58 @@
+package handler
+
+import (
+	"mal/internal/domain"
+	"mal/internal/server"
+	"net/http"
+	"time"
+
+	"github.com/gin-gonic/gin"
+)
+
+type AuthHandler struct {
+	svc domain.AuthService
+}
+
+func NewAuthHandler(svc domain.AuthService) *AuthHandler {
+	return &AuthHandler{svc: svc}
+}
+
+func (h *AuthHandler) Register(r *gin.Engine) {
+	r.GET("/login", h.HandleLoginPage)
+	r.POST("/login", h.HandleLogin)
+	r.GET("/logout", h.HandleLogout)
+}
+
+func (h *AuthHandler) HandleLoginPage(c *gin.Context) {
+	c.HTML(http.StatusOK, "login.gohtml", gin.H{
+		"CurrentPath": "/login",
+	})
+}
+
+func (h *AuthHandler) HandleLogin(c *gin.Context) {
+	username := c.PostForm("username")
+	password := c.PostForm("password")
+
+	session, err := h.svc.Login(c.Request.Context(), username, password)
+	if err != nil {
+		c.HTML(http.StatusUnauthorized, "login.gohtml", gin.H{
+			"Error":       "Invalid username or password",
+			"CurrentPath": "/login",
+		})
+		return
+	}
+
+	c.SetCookie("session_id", session.ID, int(24*time.Hour.Seconds()), "/", "", false, true)
+	c.Header("HX-Redirect", "/")
+	c.Redirect(http.StatusSeeOther, "/")
+}
+
+func (h *AuthHandler) HandleLogout(c *gin.Context) {
+	sessionID, err := c.Cookie("session_id")
+	if err == nil {
+		_ = h.svc.Logout(c.Request.Context(), sessionID)
+	}
+
+	c.SetCookie("session_id", "", -1, "/", "", false, true)
+	c.Redirect(http.StatusSeeOther, "/login")
+}

internal/auth/module.go

@@ -0,0 +1,23 @@
+package auth
+
+import (
+	"mal/internal/auth/handler"
+	"mal/internal/auth/repository"
+	"mal/internal/auth/service"
+	"mal/internal/server"
+
+	"go.uber.org/fx"
+)
+
+var Module = fx.Options(
+	fx.Provide(
+		repository.NewAuthRepository,
+		service.NewAuthService,
+		handler.NewAuthHandler,
+	),
+	fx.Provide(
+		server.AsRouteRegister(func(h *handler.AuthHandler) server.RouteRegister {
+			return h
+		}),
+	),
+)

internal/auth/repository/repository.go

@@ -0,0 +1,69 @@
+package repository
+
+import (
+	"context"
+	"database/sql"
+	"errors"
+	"mal/internal/db"
+	"mal/internal/domain"
+	"time"
+
+	"github.com/google/uuid"
+)
+
+type authRepository struct {
+	queries *db.Queries
+}
+
+func NewAuthRepository(queries *db.Queries) domain.AuthRepository {
+	return &authRepository{queries: queries}
+}
+
+func (r *authRepository) GetUserByUsername(ctx context.Context, username string) (*domain.User, error) {
+	u, err := r.queries.GetUserByUsername(ctx, username)
+	if err != nil {
+		if errors.Is(err, sql.ErrNoRows) {
+			return nil, nil
+		}
+		return nil, err
+	}
+	return &u, nil
+}
+
+func (r *authRepository) GetUserByID(ctx context.Context, id string) (*domain.User, error) {
+	u, err := r.queries.GetUser(ctx, id)
+	if err != nil {
+		if errors.Is(err, sql.ErrNoRows) {
+			return nil, nil
+		}
+		return nil, err
+	}
+	return &u, nil
+}
+
+func (r *authRepository) CreateSession(ctx context.Context, userID string, sessionID string) (*domain.Session, error) {
+	s, err := r.queries.CreateSession(ctx, db.CreateSessionParams{
+		ID:        sessionID,
+		UserID:    userID,
+		ExpiresAt: time.Now().Add(24 * time.Hour),
+	})
+	if err != nil {
+		return nil, err
+	}
+	return &s, nil
+}
+
+func (r *authRepository) GetSession(ctx context.Context, sessionID string) (*domain.Session, error) {
+	s, err := r.queries.GetSession(ctx, sessionID)
+	if err != nil {
+		if errors.Is(err, sql.ErrNoRows) {
+			return nil, nil
+		}
+		return nil, err
+	}
+	return &s, nil
+}
+
+func (r *authRepository) DeleteSession(ctx context.Context, sessionID string) error {
+	return r.queries.DeleteSession(ctx, sessionID)
+}

internal/auth/service/service.go

@@ -0,0 +1,57 @@
+package service
+
+import (
+	"context"
+	"errors"
+	"mal/internal/domain"
+	"time"
+
+	"github.com/google/uuid"
+	"golang.org/x/crypto/bcrypt"
+)
+
+type authService struct {
+	repo domain.AuthRepository
+}
+
+func NewAuthService(repo domain.AuthRepository) domain.AuthService {
+	return &authService{repo: repo}
+}
+
+func (s *authService) Login(ctx context.Context, username, password string) (*domain.Session, error) {
+	user, err := s.repo.GetUserByUsername(ctx, username)
+	if err != nil {
+		return nil, err
+	}
+	if user == nil {
+		return nil, errors.New("invalid credentials")
+	}
+
+	if err := bcrypt.CompareHashAndPassword([]byte(user.PasswordHash), []byte(password)); err != nil {
+		return nil, errors.New("invalid credentials")
+	}
+
+	sessionID := uuid.New().String()
+	return s.repo.CreateSession(ctx, user.ID, sessionID)
+}
+
+func (s *authService) ValidateSession(ctx context.Context, sessionID string) (*domain.User, error) {
+	session, err := s.repo.GetSession(ctx, sessionID)
+	if err != nil {
+		return nil, err
+	}
+	if session == nil {
+		return nil, errors.New("session not found")
+	}
+
+	if session.ExpiresAt.Before(time.Now()) {
+		_ = s.repo.DeleteSession(ctx, sessionID)
+		return nil, errors.New("session expired")
+	}
+
+	return s.repo.GetUserByID(ctx, session.UserID)
+}
+
+func (s *authService) Logout(ctx context.Context, sessionID string) error {
+	return s.repo.DeleteSession(ctx, sessionID)
+}

internal/domain/auth.go

@@ -0,0 +1,23 @@
+package domain
+
+import (
+	"context"
+	"mal/internal/db"
+)
+
+type User = db.User
+type Session = db.Session
+
+type AuthService interface {
+	Login(ctx context.Context, username, password string) (*Session, error)
+	ValidateSession(ctx context.Context, sessionID string) (*User, error)
+	Logout(ctx context.Context, sessionID string) error
+}
+
+type AuthRepository interface {
+	GetUserByUsername(ctx context.Context, username string) (*User, error)
+	GetUserByID(ctx context.Context, id string) (*User, error)
+	CreateSession(ctx context.Context, userID string, sessionID string) (*Session, error)
+	GetSession(ctx context.Context, sessionID string) (*Session, error)
+	DeleteSession(ctx context.Context, sessionID string) error
+}