[#532] Todo 카테고리가 무지성 fetch되는 현상을 해결한다 (#562)

* refactor: preference -> CategoryPreference로 수정해서 가독성 개선

* refactor: 변수 이름 수정

* feat: store에 json화 할 수 있는 Codable 채택 타입 관련 메서드 추가

* refactor: DTO에 codable 채택

* fix: TodoCategoryPreference 캐시 사용

* refactor: 생성자 위치 이동

* fix: TodoCategoryPreference 캐시 처리

* refactor: swift 6 경고 해결

* refactor: preconcurrency 제거

* fix: Auth 세션 캐싱 후 상태 전파

* fix: 위젯 세션 동기화 상태 연결

* refactor: 위젯 Todo snapshot 의존성 정리

* refactor: PushNotificationRepositoryImpl에서 카테고리 캐싱 관련 구현

* fix: RootViewModel 구독 중복 방지

* fix: Auth 세션 중복 방출 방지

* feat: 메모리 캐싱 프로토콜, 실 구현체 구현

* refactor: 메모리 캐싱으로 대체

* refactor: 메모리 캐시 저장 방식 개선

* fix: Auth 세션 관찰 흐름 단일화

Author: opficdev

Application/DevLogData/Sources/DTO/TodoCategoryPreferenceResponse.swift

@@ -7,13 +7,13 @@
 
 import Foundation
 
-public struct TodoCategoryPreferenceResponse: Equatable {
-    public enum Category: Equatable {
+public struct TodoCategoryPreferenceResponse: Equatable, Codable {
+    public enum Category: Equatable, Codable {
         case system(String)
         case user(UserCategory)
     }
 
-    public struct UserCategory: Equatable {
+    public struct UserCategory: Equatable, Codable {
         public let id: String
         public let name: String
         public let colorHex: String

Application/DevLogData/Sources/DataAssembler.swift

@@ -40,26 +40,29 @@ public final class DataAssembler: Assembler {
             TodoRepositoryImpl(
                 todoService: container.resolve(TodoService.self),
                 todoCategoryService: container.resolve(TodoCategoryService.self),
+                store: container.resolve(MemoryCacheStore.self),
                 widgetSyncEventBus: container.resolve(WidgetSyncEventBus.self),
                 todoMutationEventBus: container.resolve(TodoMutationEventBus.self)
             )
         }
 
         container.register(WidgetTodoSnapshotRepository.self) {
-            WidgetTodoSnapshotRepositoryImpl(
-                repository: container.resolve(TodoRepository.self)
-            )
+            WidgetTodoSnapshotRepositoryImpl(todoService: container.resolve(TodoService.self))
         }
 
         container.register(TodoCategoryRepository.self) {
             TodoCategoryRepositoryImpl(
-                todoCategoryService: container.resolve(TodoCategoryService.self)
+                todoCategoryService: container.resolve(TodoCategoryService.self),
+                store: container.resolve(MemoryCacheStore.self)
             )
         }
 
         container.register(AuthSessionRepository.self) {
             AuthSessionRepositoryImpl(
-                authService: container.resolve(AuthService.self)
+                authService: container.resolve(AuthService.self),
+                todoCategoryService: container.resolve(TodoCategoryService.self),
+                store: container.resolve(MemoryCacheStore.self),
+                provider: container.resolve(AuthSessionStateProvider.self)
             )
         }
 
@@ -100,7 +103,8 @@ public final class DataAssembler: Assembler {
         container.register(PushNotificationRepository.self) {
             PushNotificationRepositoryImpl(
                 pushNotificationService: container.resolve(PushNotificationService.self),
-                todoCategoryService: container.resolve(TodoCategoryService.self)
+                todoCategoryService: container.resolve(TodoCategoryService.self),
+                store: container.resolve(MemoryCacheStore.self)
             )
         }
 

Application/DevLogData/Sources/Protocol/AuthSessionStateProvider.swift

@@ -0,0 +1,13 @@
+//
+//  AuthSessionStateProvider.swift
+//  DevLogData
+//
+//  Created by opfic on 6/9/26.
+//
+
+import Combine
+
+public protocol AuthSessionStateProvider {
+    func publish(_ isSignedIn: Bool)
+    func observeSignedIn() -> AnyPublisher<Bool, Never>
+}

Application/DevLogData/Sources/Protocol/MemoryCacheStore.swift

@@ -0,0 +1,13 @@
+//
+//  MemoryCacheStore.swift
+//  DevLogData
+//
+//  Created by opfic on 6/9/26.
+//
+
+import Foundation
+
+public protocol MemoryCacheStore {
+    func value<T: Codable>(forKey key: String) -> T?
+    func setValue<T: Codable>(_ value: T?, forKey key: String)
+}

Application/DevLogData/Sources/Protocol/TodoCategoryService.swift

@@ -8,6 +8,6 @@
 import Foundation
 
 public protocol TodoCategoryService {
-    func fetchPreferences() async throws -> [TodoCategoryPreferenceResponse]
-    func updatePreferences(_ preferences: [TodoCategoryPreferenceResponse]) async throws
+    func fetchCategoryPreferences() async throws -> [TodoCategoryPreferenceResponse]
+    func updateCategoryPreferences(_ preferences: [TodoCategoryPreferenceResponse]) async throws
 }

Application/DevLogData/Sources/Protocol/UserDefaultsStore.swift

@@ -8,6 +8,9 @@
 import Foundation
 
 public protocol UserDefaultsStore {
+    func value<T: Codable>(forKey key: String) -> T?
+    func setValue<T: Codable>(_ value: T?, forKey key: String)
+    func removeValues(withPrefix prefix: String)
     func string(forKey key: String) -> String?
     func setString(_ value: String?, forKey key: String)
     func stringArray(forKey key: String) -> [String]

Application/DevLogData/Sources/Repository/AuthSessionRepositoryImpl.swift

@@ -9,13 +9,67 @@ import Combine
 import DevLogDomain
 
 final class AuthSessionRepositoryImpl: AuthSessionRepository {
+    private enum Key {
+        static let preferences = "TodoCategory.preferences"
+    }
+
     private let authService: AuthService
+    private let todoCategoryService: TodoCategoryService
+    private let store: MemoryCacheStore
+    private let provider: AuthSessionStateProvider
+    private var cancellables = Set<AnyCancellable>()
 
-    init(authService: AuthService) {
+    init(
+        authService: AuthService,
+        todoCategoryService: TodoCategoryService,
+        store: MemoryCacheStore,
+        provider: AuthSessionStateProvider
+    ) {
         self.authService = authService
+        self.todoCategoryService = todoCategoryService
+        self.store = store
+        self.provider = provider
+
+        setupObservation()
     }
 
     func observeSignedIn() -> AnyPublisher<Bool, Never> {
+        provider.observeSignedIn()
+    }
+}
+
+private extension AuthSessionRepositoryImpl {
+    func setupObservation() {
         authService.observeSignedIn()
+            .removeDuplicates()
+            .sink { [weak self] isSignedIn in
+                Task { [weak self] in
+                    guard let self else { return }
+
+                    if isSignedIn {
+                        await self.cachePreferencesIfNeeded()
+                    } else {
+                        self.clearPreferencesCache()
+                    }
+                    self.provider.publish(isSignedIn)
+                }
+            }
+            .store(in: &cancellables)
+    }
+
+    func cachePreferencesIfNeeded() async {
+        if store.value(forKey: Key.preferences) as [TodoCategoryPreferenceResponse]? != nil {
+            return
+        }
+
+        guard let preferences = try? await todoCategoryService.fetchCategoryPreferences() else {
+            return
+        }
+
+        store.setValue(preferences, forKey: Key.preferences)
+    }
+
+    func clearPreferencesCache() {
+        store.setValue(Optional<[TodoCategoryPreferenceResponse]>.none, forKey: Key.preferences)
     }
 }

Application/DevLogData/Sources/Repository/PushNotificationRepositoryImpl.swift

@@ -11,15 +11,22 @@ import DevLogCore
 import DevLogDomain
 
 final class PushNotificationRepositoryImpl: PushNotificationRepository {
+    private enum Key {
+        static let preferences = "TodoCategory.preferences"
+    }
+
     private let pushNotificationService: PushNotificationService
     private let todoCategoryService: TodoCategoryService
+    private let store: MemoryCacheStore
 
     init(
         pushNotificationService: PushNotificationService,
-        todoCategoryService: TodoCategoryService
+        todoCategoryService: TodoCategoryService,
+        store: MemoryCacheStore
     ) {
         self.pushNotificationService = pushNotificationService
         self.todoCategoryService = todoCategoryService
+        self.store = store
     }
 
     /// 푸시 알림 On/Off 설정
@@ -59,7 +66,7 @@ final class PushNotificationRepositoryImpl: PushNotificationRepository {
         do {
             let cursorDTO = cursor.map { PushNotificationCursorDTO.fromDomain($0) }
             async let responseTask = pushNotificationService.requestNotifications(query, cursor: cursorDTO)
-            async let preferencesTask = todoCategoryService.fetchPreferences()
+            async let preferencesTask = todoCategoryPreferenceResponses()
 
             let (response, preferenceResponses) = try await (responseTask, preferencesTask)
             return try resolvePage(from: response, with: preferenceResponses.toDomain())
@@ -91,7 +98,8 @@ final class PushNotificationRepositoryImpl: PushNotificationRepository {
 
                         Task {
                             do {
-                                let preferences = try await self.todoCategoryService.fetchPreferences().toDomain()
+                                let preferences = try await self.todoCategoryPreferenceResponses()
+                                    .toDomain()
                                 let page = try self.resolvePage(from: response, with: preferences)
                                 subject.send(page)
                             } catch {
@@ -147,6 +155,16 @@ final class PushNotificationRepositoryImpl: PushNotificationRepository {
 }
 
 private extension PushNotificationRepositoryImpl {
+    func todoCategoryPreferenceResponses() async throws -> [TodoCategoryPreferenceResponse] {
+        if let preferences: [TodoCategoryPreferenceResponse] = store.value(forKey: Key.preferences) {
+            return preferences
+        }
+
+        let preferences = try await todoCategoryService.fetchCategoryPreferences()
+        store.setValue(preferences, forKey: Key.preferences)
+        return preferences
+    }
+
     func resolvePage(
         from response: PushNotificationPageResponse,
         with preferences: [TodoCategoryPreference]

Application/DevLogData/Sources/Repository/TodoCategoryRepositoryImpl.swift

@@ -8,25 +8,40 @@
 import DevLogDomain
 
 final class TodoCategoryRepositoryImpl: TodoCategoryRepository {
+    private enum Key {
+        static let preferences = "TodoCategory.preferences"
+    }
+
     private let todoCategoryService: TodoCategoryService
+    private let store: MemoryCacheStore
 
-    init(todoCategoryService: TodoCategoryService) {
+    init(
+        todoCategoryService: TodoCategoryService,
+        store: MemoryCacheStore
+    ) {
         self.todoCategoryService = todoCategoryService
+        self.store = store
     }
 
-    func fetchPreferences() async throws -> [TodoCategoryPreference] {
+    func fetchCategoryPreferences() async throws -> [TodoCategoryPreference] {
         do {
-            return try await todoCategoryService.fetchPreferences().toDomain()
+            if let preferences: [TodoCategoryPreferenceResponse] = store.value(forKey: Key.preferences) {
+                return preferences.toDomain()
+            }
+
+            let responses = try await todoCategoryService.fetchCategoryPreferences()
+            store.setValue(responses, forKey: Key.preferences)
+            return responses.toDomain()
         } catch {
             throw error.toDomain()
         }
     }
 
-    func updatePreferences(_ preferences: [TodoCategoryPreference]) async throws {
+    func updateCategoryPreferences(_ preferences: [TodoCategoryPreference]) async throws {
         do {
-            try await todoCategoryService.updatePreferences(
-                preferences.map(TodoCategoryPreferenceResponse.fromDomain)
-            )
+            let responses = preferences.map(TodoCategoryPreferenceResponse.fromDomain)
+            try await todoCategoryService.updateCategoryPreferences(responses)
+            store.setValue(responses, forKey: Key.preferences)
         } catch {
             throw error.toDomain()
         }

Application/DevLogData/Sources/Repository/TodoRepositoryImpl.swift

@@ -10,19 +10,26 @@ import DevLogCore
 import DevLogDomain
 
 final class TodoRepositoryImpl: TodoRepository {
+    private enum Key {
+        static let preferences = "TodoCategory.preferences"
+    }
+
     private let todoService: TodoService
     private let todoCategoryService: TodoCategoryService
+    private let store: MemoryCacheStore
     private let widgetSyncEventBus: WidgetSyncEventBus
     private let todoMutationEventBus: TodoMutationEventBus
 
     init(
         todoService: TodoService,
         todoCategoryService: TodoCategoryService,
+        store: MemoryCacheStore,
         widgetSyncEventBus: WidgetSyncEventBus,
         todoMutationEventBus: TodoMutationEventBus
     ) {
         self.todoService = todoService
         self.todoCategoryService = todoCategoryService
+        self.store = store
         self.widgetSyncEventBus = widgetSyncEventBus
         self.todoMutationEventBus = todoMutationEventBus
     }
@@ -31,11 +38,16 @@ final class TodoRepositoryImpl: TodoRepository {
         let responseCursor = cursor.map { TodoCursorDTO.fromDomain($0) }
 
         do {
-            async let response = todoService.fetchTodos(query, cursor: responseCursor)
-            async let preferences = todoCategoryService.fetchPreferences()
-
-            let (todoResponse, todoPreferenceResponses) = try await (response, preferences)
-            let userTodoCategories: [UserTodoCategory] = todoPreferenceResponses.toDomain().compactMap { preference in
+            async let todos = todoService.fetchTodos(query, cursor: responseCursor)
+            async let preferences = todoCategoryPreferenceResponses()
+
+            let (todoResponse, todoPreferenceResponses) = try await (
+                todos,
+                preferences
+            )
+            let userTodoCategories: [UserTodoCategory] = todoPreferenceResponses
+                .toDomain()
+                .compactMap { preference in
                 guard case .user(let category) = preference.category else {
                     return nil
                 }
@@ -59,10 +71,15 @@ final class TodoRepositoryImpl: TodoRepository {
     func fetchTodo(_ todoId: String) async throws -> Todo {
         do {
             async let response = todoService.fetchTodo(todoId: todoId)
-            async let preferences = todoCategoryService.fetchPreferences()
-
-            let (todoResponse, todoPreferenceResponses) = try await (response, preferences)
-            let userTodoCategories: [UserTodoCategory] = todoPreferenceResponses.toDomain().compactMap { preference in
+            async let preferences = todoCategoryPreferenceResponses()
+
+            let (todoResponse, todoPreferenceResponses) = try await (
+                response,
+                preferences
+            )
+            let userTodoCategories: [UserTodoCategory] = todoPreferenceResponses
+                .toDomain()
+                .compactMap { preference in
                 guard case .user(let category) = preference.category else {
                     return nil
                 }
@@ -79,10 +96,15 @@ final class TodoRepositoryImpl: TodoRepository {
     func fetchReferences(_ numbers: [Int]) async throws -> [Int: TodoReference] {
         do {
             async let responseTask = todoService.fetchReferences(numbers)
-            async let preferencesTask = todoCategoryService.fetchPreferences()
-
-            let (responses, preferenceResponses) = try await (responseTask, preferencesTask)
-            let userTodoCategories: [UserTodoCategory] = preferenceResponses.toDomain().compactMap { preference in
+            async let preferencesTask = todoCategoryPreferenceResponses()
+
+            let (responses, preferenceResponses) = try await (
+                responseTask,
+                preferencesTask
+            )
+            let userTodoCategories: [UserTodoCategory] = preferenceResponses
+                .toDomain()
+                .compactMap { preference in
                 guard case .user(let category) = preference.category else {
                     return nil
                 }
@@ -149,6 +171,16 @@ final class TodoRepositoryImpl: TodoRepository {
 }
 
 private extension TodoRepositoryImpl {
+    func todoCategoryPreferenceResponses() async throws -> [TodoCategoryPreferenceResponse] {
+        if let preferences: [TodoCategoryPreferenceResponse] = store.value(forKey: Key.preferences) {
+            return preferences
+        }
+
+        let preferences = try await todoCategoryService.fetchCategoryPreferences()
+        store.setValue(preferences, forKey: Key.preferences)
+        return preferences
+    }
+
     func resolve(
         _ response: TodoResponse,
         userTodoCategories: [UserTodoCategory]