clean: refactor DI and container initialization

api/dependecyInjection.go

@@ -10,7 +10,7 @@ import (
 	"path/filepath"
 )
 
-type LocalContainer struct {
+type UseCases struct {
 	CreatePostUseCase *useCases.CreatePostUseCase
 	GetPostUseCase    *useCases.GetPostUseCase
 	ListPostsUseCase  *useCases.ListPostsUseCase
@@ -20,57 +20,40 @@ type LocalContainer struct {
 	GetPageUseCase    *useCases.GetPageUseCase
 }
 
-var Container *LocalContainer
+var Container *UseCases
-
-func setContainer(
-	createPost *useCases.CreatePostUseCase,
-	getPost *useCases.GetPostUseCase,
-	listPost *useCases.ListPostsUseCase,
-	getUser *useCases.GetUserUseCase,
-	createUser *useCases.CreateUserUseCase,
-	listUsers *useCases.ListUsersUseCase,
-	getPage *useCases.GetPageUseCase,
-) *LocalContainer {
-	Container = &LocalContainer{
-		CreatePostUseCase: createPost,
-		GetPostUseCase:    getPost,
-		ListPostsUseCase:  listPost,
-		GetUserUseCase:    getUser,
-		CreateUserUseCase: createUser,
-		ListUsersUseCase:  listUsers,
-		GetPageUseCase:    getPage,
-	}
-	return Container
-}
-
-func InitContainer() {
-	if Container != nil {
-		return
-	}
-
-	digContainer := dig.New()
 
+func getDb() *gorm.DB {
 	dbName := os.Getenv("DB_FILE")
 	if err := os.MkdirAll(filepath.Dir(dbName), os.ModePerm); err != nil {
 		panic("Unable to create necessary subdirectories: " + err.Error())
 	}
-
 	db, err := gorm.Open(sqlite.Open(dbName), &gorm.Config{})
 	if err != nil {
 		panic("Unable to open the database: " + err.Error())
 	}
+	return db
+}
 
-	_ = db.AutoMigrate(&models.Post{}, &models.User{})
+func InitContainer() {
+	digContainer := dig.New()
 
-	_ = digContainer.Provide(func() *gorm.DB { return db })
+	database := getDb()
+	_ = database.AutoMigrate(&models.Post{}, &models.User{})
+	_ = digContainer.Provide(func() *gorm.DB { return database })
 
-	_ = digContainer.Provide(func(db *gorm.DB) *useCases.CreatePostUseCase { return useCases.NewCreatePostUseCase(db) })
+	_ = digContainer.Provide(func(db *gorm.DB) *UseCases {
-	_ = digContainer.Provide(func(db *gorm.DB) *useCases.GetPostUseCase { return useCases.NewGetPostUseCase(db) })
+		return &UseCases{
-	_ = digContainer.Provide(func(db *gorm.DB) *useCases.ListPostsUseCase { return useCases.NewListPostsUseCase(db) })
+			CreatePostUseCase: useCases.NewCreatePostUseCase(db),
-	_ = digContainer.Provide(func(db *gorm.DB) *useCases.GetUserUseCase { return useCases.NewGetUserUseCase(db) })
+			GetPostUseCase:    useCases.NewGetPostUseCase(db),
-	_ = digContainer.Provide(func(db *gorm.DB) *useCases.CreateUserUseCase { return useCases.NewCreateUserUseCase(db) })
+			ListPostsUseCase:  useCases.NewListPostsUseCase(db),
-	_ = digContainer.Provide(func(db *gorm.DB) *useCases.ListUsersUseCase { return useCases.NewListUsersUseCase(db) })
+			GetUserUseCase:    useCases.NewGetUserUseCase(db),
-	_ = digContainer.Provide(useCases.NewGetPageUseCase)
+			CreateUserUseCase: useCases.NewCreateUserUseCase(db),
-
+			ListUsersUseCase:  useCases.NewListUsersUseCase(db),
-	_ = digContainer.Invoke(setContainer)
+			GetPageUseCase:    useCases.NewGetPageUseCase(),
+		}
+	})
+	err := digContainer.Invoke(func(useCases *UseCases) { Container = useCases })
+	if err != nil {
+		panic("Unable to invoke container: " + err.Error())
+	}
 }