[#68] Data 레이어에서 DTO를 제거한다

DevLog/Data/Common/Error+.swift

@@ -27,3 +27,24 @@ enum FirestoreError: Error, LocalizedError {
 enum UIError: Error {
     case notFoundTopViewController
 }
+
+enum DataError: Error {
+    case invalidData(context: String)
+
+    private static let logger = Logger(category: "DataError")
+
+    static func invalidData(
+        _ context: String,
+        file: String = #file,
+        function: String = #function,
+        line: Int = #line
+    ) -> DataError {
+        logger.error(
+            "Invalid data: \(context)",
+            file: file,
+            function: function,
+            line: line
+        )
+        return .invalidData(context: context)
+    }
+}

DevLog/Data/Mapper/TodoMapping.swift

@@ -0,0 +1,49 @@
+//
+//  TodoMapping.swift
+//  DevLog
+//
+//  Created by 최윤진 on 2/19/26.
+//
+
+extension TodoRequest {
+    static func fromDomain(_ entity: Todo) -> Self {
+        TodoRequest(
+            id: entity.id,
+            isPinned: entity.isPinned,
+            isCompleted: entity.isCompleted,
+            isChecked: entity.isChecked,
+            title: entity.title,
+            content: entity.content,
+            createdAt: entity.createdAt,
+            updatedAt: entity.updatedAt,
+            dueDate: entity.dueDate,
+            tags: entity.tags,
+            kind: entity.kind
+        )
+    }
+}
+
+extension TodoResponse {
+    func toDomain() throws -> Todo {
+        guard let id = self.id else {
+            throw DataError.invalidData("TodoResponse.id is nil")
+        }
+        guard let kind = TodoKind(rawValue: self.kind) else {
+            throw DataError.invalidData("TodoResponse.kind is invalid: \(self.kind)")
+        }
+
+        return Todo(
+            id: id,
+            isPinned: self.isPinned,
+            isCompleted: self.isCompleted,
+            isChecked: self.isChecked,
+            title: self.title,
+            content: self.content,
+            createdAt: self.createdAt,
+            updatedAt: self.updatedAt,
+            dueDate: self.dueDate,
+            tags: self.tags,
+            kind: kind
+        )
+    }
+}

DevLog/Data/Mapper/UserProfileMapping.swift

@@ -0,0 +1,17 @@
+//
+//  UserProfileMapping.swift
+//  DevLog
+//
+//  Created by 최윤진 on 2/19/26.
+//
+
+extension UserProfileResponse {
+    func toDomain() -> UserProfile {
+        UserProfile(
+            name: self.name,
+            email: self.email,
+            statusMessage: self.statusMessage,
+            avatarURL: self.avatarURL
+        )
+    }
+}

DevLog/Data/DTO/WebPageMetadata.swift → DevLog/Data/Mapper/WebPageMapping.swift

@@ -1,18 +1,11 @@
 //
-//  WebPageMetadata.swift
+//  WebPageMapping.swift
 //  DevLog
 //
-//  Created by 최윤진 on 2/9/26.
+//  Created by 최윤진 on 2/19/26.
 //
 
-import Foundation
-
-struct WebPageMetadata: Hashable {
-    let title: String?
-    let url: URL
-    let displayURL: URL
-    let imageURL: URL?
-
+extension WebPageResponse {
     func toDomain() -> WebPage {
         WebPage(
             title: title,

DevLog/Data/Protocol/AuthenticationService.swift

@@ -8,7 +8,7 @@
 import Foundation
 
 protocol AuthenticationService {
-    func signIn() async throws -> AuthenticationDataResponse
+    func signIn() async throws -> AuthDataResponse
     func signOut(_ uid: String) async throws
     func deleteAuth(_ uid: String) async throws
     func link(uid: String, email: String) async throws

DevLog/Data/Repository/AuthenticationRepositoryImpl.swift

@@ -27,7 +27,7 @@ final class AuthenticationRepositoryImpl: AuthenticationRepository {
     }
 
     func signIn(_ provider: AuthProvider) async throws {
-        let response: AuthenticationDataResponse
+        let response: AuthDataResponse
         switch provider {
         case .apple:
             response = try await appleAuthService.signIn()

DevLog/Data/Repository/TodoRepositoryImpl.swift

@@ -16,17 +16,21 @@ final class TodoRepositoryImpl: TodoRepository {
 
     func fetchTodos(_ kind: TodoKind) async throws -> [Todo] {
         let response = try await todoService.fetchTodos(kind: kind)
-        return response.map { $0.toDomain() }
+        return try response.map { item in
+            try item.toDomain()
+        }
     }
 
     func fetchPinnedTodos() async throws -> [Todo] {
         let response = try await todoService.fetchPinnedTodos()
-        return response.map { $0.toDomain() }
+        return try response.map { item in
+            try item.toDomain()
+        }
     }
 
     func fetchTodo(_ todoID: String) async throws -> Todo {
         let response = try await todoService.fetchTodo(todoID: todoID)
-        return response.toDomain()
+        return try response.toDomain()
     }
 
     func upsertTodo(_ todo: Todo) async throws {

DevLog/Data/Repository/WebPageRepositoryImpl.swift

@@ -17,31 +17,32 @@ final class WebPageRepositoryImpl: WebPageRepository {
         self.metadataService = metadataService
     }
 
-    func fetch() async throws -> [WebPageMetadata] {
+    func fetch() async throws -> [WebPage] {
         let responses = try await webPageService.fetchWebPages()
         let indexedResponses = responses.enumerated().map { ($0.offset, $0.element) }
 
-        return try await withThrowingTaskGroup(of: (Int, WebPageMetadata?).self) { group in
+        return try await withThrowingTaskGroup(of: (Int, WebPageResponse?).self) { group in
             for (index, response) in indexedResponses {
                 group.addTask {
                     let metadata = try? await self.metadataService.fetchMetadata(from: response)
                     return (index, metadata)
                 }
             }
 
-            var results: [WebPageMetadata?] = Array(repeating: nil, count: responses.count)
+            var results: [WebPageResponse?] = Array(repeating: nil, count: responses.count)
             for try await (index, metadata) in group {
                 results[index] = metadata
             }
 
-            return results.compactMap { $0 }
+            return results.compactMap { $0?.toDomain() }
         }
     }
 
-    func upsert(_ urlString: String) async throws -> WebPageMetadata {
+    func upsert(_ urlString: String) async throws -> WebPage {
         try await webPageService.upsertWebPage(urlString)
-        let response = WebPageResponse(urlString: urlString)
-        return try await metadataService.fetchMetadata(from: response)
+        let response = WebPageURLResponse(urlString: urlString)
+        let metadata = try await metadataService.fetchMetadata(from: response)
+        return metadata.toDomain()
     }
 
     func delete(_ urlString: String) async throws {

DevLog/Domain/Protocol/WebPageRepository.swift

@@ -6,7 +6,7 @@
 //
 
 protocol WebPageRepository {
-    func fetch() async throws -> [WebPageMetadata]
-    func upsert(_ urlString: String) async throws -> WebPageMetadata
+    func fetch() async throws -> [WebPage]
+    func upsert(_ urlString: String) async throws -> WebPage
     func delete(_ urlString: String) async throws
 }

DevLog/Domain/UseCase/WebPage/Fetch/FetchWebPagesUseCaseImpl.swift

@@ -13,6 +13,6 @@ final class FetchWebPagesUseCaseImpl: FetchWebPagesUseCase {
     }
 
     func execute() async throws -> [WebPage] {
-        return try await repository.fetch().map { $0.toDomain() }
+        try await repository.fetch()
     }
 }

DevLog/Domain/UseCase/WebPage/Upsert/AddWebPageUseCaseImpl.swift

@@ -13,6 +13,6 @@ final class AddWebPageUseCaseImpl: AddWebPageUseCase {
     }
 
     func execute(_ urlString: String) async throws -> WebPage {
-        try await repository.upsert(urlString).toDomain()
+        try await repository.upsert(urlString)
     }
 }

DevLog/Data/DTO/AuthenticationData+.swift → DevLog/Infra/DTO/AuthDataResponse.swift

@@ -1,13 +1,13 @@
 //
-//  AuthenticationData+.swift
+//  AuthDataResponse.swift
 //  DevLog
 //
 //  Created by 최윤진 on 11/2/25.
 //
 
 import Foundation
 
-struct AuthenticationDataResponse {
+struct AuthDataResponse {
     let uid: String
     let displayName: String?
     let email: String?

DevLog/Data/DTO/Todo+.swift → DevLog/Infra/DTO/TodoDTO.swift

@@ -1,5 +1,5 @@
 //
-//  Todo+.swift
+//  TodoDTO.swift
 //  DevLog
 //
 //  Created by 최윤진 on 12/14/25.
@@ -21,21 +21,6 @@ struct TodoRequest: Dictionaryable {
     let tags: [String]
     let kind: TodoKind
 
-    static func fromDomain(_ entity: Todo) -> Self {
-        TodoRequest(
-            id: entity.id,
-            isPinned: entity.isPinned,
-            isCompleted: entity.isCompleted,
-            isChecked: entity.isChecked,
-            title: entity.title,
-            content: entity.content,
-            createdAt: entity.createdAt,
-            updatedAt: entity.updatedAt,
-            dueDate: entity.dueDate,
-            tags: entity.tags,
-            kind: entity.kind
-        )
-    }
 }
 
 struct TodoResponse: Decodable {
@@ -45,9 +30,9 @@ struct TodoResponse: Decodable {
     let isChecked: Bool
     let title: String
     let content: String
-    let createdAt: Timestamp
-    let updatedAt: Timestamp
-    let dueDate: Timestamp?
+    let createdAt: Date
+    let updatedAt: Date
+    let dueDate: Date?
     let tags: [String]
     let kind: String
 
@@ -68,8 +53,8 @@ struct TodoResponse: Decodable {
             let isChecked = data["isChecked"] as? Bool,
             let title = data["title"] as? String,
             let content = data["content"] as? String,
-            let createdAt = data["createdAt"] as? Timestamp,
-            let updatedAt = data["updatedAt"] as? Timestamp,
+            let createdAtTimestamp = data["createdAt"] as? Timestamp,
+            let updatedAtTimestamp = data["updatedAt"] as? Timestamp,
             let tags = data["tags"] as? [String],
             let kind = data["kind"] as? String else {
             return nil
@@ -80,26 +65,15 @@ struct TodoResponse: Decodable {
         self.isChecked = isChecked
         self.title = title
         self.content = content
-        self.createdAt = createdAt
-        self.updatedAt = updatedAt
-        self.dueDate = data["dueDate"] as? Timestamp
+        self.createdAt = createdAtTimestamp.dateValue()
+        self.updatedAt = updatedAtTimestamp.dateValue()
+        if let dueDateTimestamp = data["dueDate"] as? Timestamp {
+            self.dueDate = dueDateTimestamp.dateValue()
+        } else {
+            self.dueDate = nil
+        }
         self.tags = tags
         self.kind = kind
     }
 
-    func toDomain() -> Todo {
-        Todo(
-            id: self.id == nil ? UUID().uuidString : self.id!,
-            isPinned: self.isPinned,
-            isCompleted: self.isCompleted,
-            isChecked: self.isChecked,
-            title: self.title,
-            content: self.content,
-            createdAt: self.createdAt.dateValue(),
-            updatedAt: self.updatedAt.dateValue(),
-            dueDate: self.dueDate?.dateValue(),
-            tags: self.tags,
-            kind: TodoKind(rawValue: self.kind) ?? .etc
-        )
-    }
 }

DevLog/Infra/DTO/UserProfileResponse.swift

@@ -0,0 +1,15 @@
+//
+//  UserProfileResponse.swift
+//  DevLog
+//
+//  Created by 최윤진 on 1/10/26.
+//
+
+import Foundation
+
+struct UserProfileResponse: Decodable {
+    let name: String
+    let email: String
+    let statusMessage: String
+    let avatarURL: URL?
+}

DevLog/Infra/DTO/WebPageResponse.swift

@@ -5,6 +5,11 @@
 //  Created by 최윤진 on 2/9/26.
 //
 
+import Foundation
+
 struct WebPageResponse {
-    let urlString: String
+    let title: String?
+    let url: URL
+    let displayURL: URL
+    let imageURL: URL?
 }

DevLog/Infra/DTO/WebPageURLResponse.swift

@@ -0,0 +1,10 @@
+//
+//  WebPageURLResponse.swift
+//  DevLog
+//
+//  Created by 최윤진 on 2/9/26.
+//
+
+struct WebPageURLResponse {
+    let urlString: String
+}