refactlr: CoreDataError 타입 생성, 예외처리 추가

Diary+CoreDataClass.swift

@@ -6,10 +6,7 @@
 //
 //
 
-import Foundation
 import CoreData
 
 @objc(Diary)
-public class Diary: NSManagedObject {
-
-}
+public class Diary: NSManagedObject {}

Diary+CoreDataProperties.swift

@@ -6,11 +6,9 @@
 //
 //
 
-import Foundation
 import CoreData
 
 extension Diary {
-
     @nonobjc public class func fetchRequest() -> NSFetchRequest<Diary> {
         return NSFetchRequest<Diary>(entityName: "Diary")
     }
@@ -19,7 +17,6 @@ extension Diary {
     @NSManaged public var body: String?
     @NSManaged public var createdAt: Date?
     @NSManaged public var id: UUID?
-
 }
 
 extension Diary: Identifiable {}

Diary.xcodeproj/project.pbxproj

@@ -19,7 +19,8 @@
 		BA1A55EB2A9D84AF0012C89D /* DiaryEntity.swift in Sources */ = {isa = PBXBuildFile; fileRef = BA1A55EA2A9D84AF0012C89D /* DiaryEntity.swift */; };
 		BA1A55ED2A9D90810012C89D /* DateFormatter+.swift in Sources */ = {isa = PBXBuildFile; fileRef = BA1A55EC2A9D90810012C89D /* DateFormatter+.swift */; };
 		BABBDAE52A9F13A200D8D50B /* DecodingError.swift in Sources */ = {isa = PBXBuildFile; fileRef = BABBDAE42A9F13A200D8D50B /* DecodingError.swift */; };
-		BABBDB342AA6D05A00D8D50B /* ShareDiary.swift in Sources */ = {isa = PBXBuildFile; fileRef = BABBDB332AA6D05A00D8D50B /* ShareDiary.swift */; };
+		BABBDB342AA6D05A00D8D50B /* ShareDisplayable.swift in Sources */ = {isa = PBXBuildFile; fileRef = BABBDB332AA6D05A00D8D50B /* ShareDisplayable.swift */; };
+		BABBDB362AAD904100D8D50B /* CoreDataError.swift in Sources */ = {isa = PBXBuildFile; fileRef = BABBDB352AAD904100D8D50B /* CoreDataError.swift */; };
 		C739AE25284DF28600741E8F /* AppDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = C739AE24284DF28600741E8F /* AppDelegate.swift */; };
 		C739AE27284DF28600741E8F /* SceneDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = C739AE26284DF28600741E8F /* SceneDelegate.swift */; };
 		C739AE29284DF28600741E8F /* DiaryListViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = C739AE28284DF28600741E8F /* DiaryListViewController.swift */; };
@@ -41,7 +42,8 @@
 		BA1A55EA2A9D84AF0012C89D /* DiaryEntity.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DiaryEntity.swift; sourceTree = "<group>"; };
 		BA1A55EC2A9D90810012C89D /* DateFormatter+.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "DateFormatter+.swift"; sourceTree = "<group>"; };
 		BABBDAE42A9F13A200D8D50B /* DecodingError.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DecodingError.swift; sourceTree = "<group>"; };
-		BABBDB332AA6D05A00D8D50B /* ShareDiary.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ShareDiary.swift; sourceTree = "<group>"; };
+		BABBDB332AA6D05A00D8D50B /* ShareDisplayable.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ShareDisplayable.swift; sourceTree = "<group>"; };
+		BABBDB352AAD904100D8D50B /* CoreDataError.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CoreDataError.swift; sourceTree = "<group>"; };
 		C739AE21284DF28600741E8F /* Diary.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = Diary.app; sourceTree = BUILT_PRODUCTS_DIR; };
 		C739AE24284DF28600741E8F /* AppDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = AppDelegate.swift; sourceTree = "<group>"; };
 		C739AE26284DF28600741E8F /* SceneDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SceneDelegate.swift; sourceTree = "<group>"; };
@@ -87,7 +89,7 @@
 			isa = PBXGroup;
 			children = (
 				636B19AB2AA6C5E900B5242D /* AlertDisplayble.swift */,
-				BABBDB332AA6D05A00D8D50B /* ShareDiary.swift */,
+				BABBDB332AA6D05A00D8D50B /* ShareDisplayable.swift */,
 			);
 			path = Protocol;
 			sourceTree = "<group>";
@@ -150,6 +152,7 @@
 			isa = PBXGroup;
 			children = (
 				BABBDAE42A9F13A200D8D50B /* DecodingError.swift */,
+				BABBDB352AAD904100D8D50B /* CoreDataError.swift */,
 			);
 			path = Error;
 			sourceTree = "<group>";
@@ -318,7 +321,8 @@
 				63BB62B52AA182AA00524DCB /* CoreDataManager.swift in Sources */,
 				63E527392A9D97160000FBA6 /* CreateDiaryViewController.swift in Sources */,
 				BABBDAE52A9F13A200D8D50B /* DecodingError.swift in Sources */,
-				BABBDB342AA6D05A00D8D50B /* ShareDiary.swift in Sources */,
+				BABBDB362AAD904100D8D50B /* CoreDataError.swift in Sources */,
+				BABBDB342AA6D05A00D8D50B /* ShareDisplayable.swift in Sources */,
 				63BB62B32AA181BE00524DCB /* Diary+CoreDataProperties.swift in Sources */,
 				BA1A55EB2A9D84AF0012C89D /* DiaryEntity.swift in Sources */,
 				63BB62B22AA181BE00524DCB /* Diary+CoreDataClass.swift in Sources */,

Diary/App/SceneDelegate.swift

@@ -49,7 +49,11 @@ class SceneDelegate: UIResponder, UIWindowSceneDelegate {
         // to restore the scene back to its current state.
 
         // Save changes in the application's managed object context when the application transitions to the background.
-        CoreDataManager.shared.saveContext()
+        do {
+            try CoreDataManager.shared.saveContext()
+        } catch {
+            fatalError(CoreDataError.saveFailure.message)
+        }
     }
 
 

Diary/Controller/CreateDiaryViewController.swift

@@ -7,7 +7,7 @@
 
 import UIKit
 
-final class CreateDiaryViewController: UIViewController, AlertDisplayable, ShareDiary {
+final class CreateDiaryViewController: UIViewController, AlertDisplayable, ShareDisplayable {
     private let textView: UITextView = {
         let textView = UITextView()
         textView.translatesAutoresizingMaskIntoConstraints = false
@@ -94,8 +94,20 @@ final class CreateDiaryViewController: UIViewController, AlertDisplayable, Share
         let cancelAction = UIAlertAction(title: "취소", style: .cancel)
         let deleteAction = UIAlertAction(title: "삭제", style: .destructive) { [weak self] _ in
             guard let self else { return }
-            CoreDataManager.shared.deleteDiary(self.diary)
-            self.navigationController?.popViewController(animated: true)
+            do {
+                try CoreDataManager.shared.deleteDiary(self.diary)
+                self.navigationController?.popViewController(animated: true)
+            } catch CoreDataError.deleteFailure {
+                let cancelAction = UIAlertAction(title: "확인", style: .cancel)
+                self.showAlert(title: CoreDataError.deleteFailure.alertTitle,
+                               message: CoreDataError.deleteFailure.message,
+                               actions: [cancelAction])
+            } catch {
+                let cancelAction = UIAlertAction(title: "확인", style: .cancel)
+                self.showAlert(title: CoreDataError.deleteFailure.alertTitle,
+                               message: CoreDataError.unknown.message,
+                               actions: [cancelAction])
+            }
         }
 
         showAlert(title: "진짜요?", message: "정말로 삭제하시겠어요?", actions: [cancelAction, deleteAction])
@@ -141,13 +153,24 @@ extension CreateDiaryViewController {
     }
 }
 
-// MARK: - UITextViewDelegate
 extension CreateDiaryViewController: UITextViewDelegate {
     func textViewDidEndEditing(_ textView: UITextView) {
         let contents = textView.text.split(separator: "\n")
         guard !contents.isEmpty else { return }
 
-        CoreDataManager.shared.saveContext()
+        do {
+            try CoreDataManager.shared.saveContext()
+        } catch CoreDataError.saveFailure {
+            let cancelAction = UIAlertAction(title: "확인", style: .cancel)
+            self.showAlert(title: CoreDataError.saveFailure.alertTitle,
+                           message: CoreDataError.saveFailure.message,
+                           actions: [cancelAction])
+        } catch {
+            let cancelAction = UIAlertAction(title: "확인", style: .cancel)
+            self.showAlert(title: CoreDataError.saveFailure.alertTitle,
+                           message: CoreDataError.unknown.message,
+                           actions: [cancelAction])
+        }
     }
 
     func textViewDidChange(_ textView: UITextView) {

Diary/Controller/DiaryListViewController.swift

@@ -69,9 +69,16 @@ extension DiaryListViewController: AlertDisplayable {
             let fetchedDiaries = try CoreDataManager.shared.fetchDiary()
             diaryList = fetchedDiaries.filter { $0.title != nil }
             tableView.reloadData()
+        } catch CoreDataError.dataNotFound {
+            let cancelAction = UIAlertAction(title: "확인", style: .cancel)
+            showAlert(title: CoreDataError.dataNotFound.alertTitle,
+                      message: CoreDataError.dataNotFound.message,
+                      actions: [cancelAction])
         } catch {
             let cancelAction = UIAlertAction(title: "확인", style: .cancel)
-            showAlert(title: "로드 실패", message: "데이터를 불러오지 못했습니다.", actions: [cancelAction])
+            showAlert(title: CoreDataError.dataNotFound.alertTitle,
+                      message: CoreDataError.unknown.message,
+                      actions: [cancelAction])
         }
     }
 }
@@ -100,7 +107,7 @@ extension DiaryListViewController: UITableViewDataSource {
     }
 }
 
-extension DiaryListViewController: UITableViewDelegate, ShareDiary {
+extension DiaryListViewController: UITableViewDelegate, ShareDisplayable {
     func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
         tableView.deselectRow(at: indexPath, animated: true)
         let diaryToEdit = diaryList[indexPath.row]
@@ -113,10 +120,21 @@ extension DiaryListViewController: UITableViewDelegate, ShareDiary {
     UISwipeActionsConfiguration? {
         let delete = UIContextualAction(style: .normal, title: "") { (_, _, success: @escaping (Bool) -> Void) in
             let selectedDiary = self.diaryList[indexPath.row]
-
-            CoreDataManager.shared.deleteDiary(selectedDiary)
-            self.readCoreData()
-            success(true)
+            do {
+                try CoreDataManager.shared.deleteDiary(selectedDiary)
+                self.readCoreData()
+                success(true)
+            } catch CoreDataError.deleteFailure {
+                let cancelAction = UIAlertAction(title: "확인", style: .cancel)
+                self.showAlert(title: CoreDataError.deleteFailure.alertTitle,
+                               message: CoreDataError.deleteFailure.message,
+                               actions: [cancelAction])
+            } catch {
+                let cancelAction = UIAlertAction(title: "확인", style: .cancel)
+                self.showAlert(title: CoreDataError.deleteFailure.alertTitle,
+                               message: CoreDataError.unknown.message,
+                               actions: [cancelAction])
+            }
         }
 
         let share = UIContextualAction(style: .normal, title: "") { (_, _, success: @escaping (Bool) -> Void) in

Diary/DataManager/CoreDataManager.swift

@@ -16,8 +16,12 @@ class CoreDataManager {
         let sortByDate = NSSortDescriptor(key: "createdAt", ascending: false)
         request.sortDescriptors = [sortByDate]
 
-        let diaries = try persistentContainer.viewContext.fetch(request)
-        return diaries
+        do {
+            let diaries = try persistentContainer.viewContext.fetch(request)
+            return diaries
+        } catch {
+            throw CoreDataError.dataNotFound
+        }
     }
 
     func createDiary() -> Diary {
@@ -28,14 +32,14 @@ class CoreDataManager {
         return newDiary
     }
 
-    func deleteDiary(_ diary: Diary?) {
-        if let diary = diary {
-            persistentContainer.viewContext.delete(diary)
-            saveContext()
+    func deleteDiary(_ diary: Diary?) throws {
+        guard let diary = diary else {
+            throw CoreDataError.deleteFailure
         }
+        persistentContainer.viewContext.delete(diary)
+        try saveContext()
     }
 
-    // MARK: - Core Data stack
     lazy var persistentContainer: NSPersistentContainer = {
         let container = NSPersistentContainer(name: "Diary")
         container.loadPersistentStores(completionHandler: { (_, error) in
@@ -46,15 +50,13 @@ class CoreDataManager {
         return container
     }()
 
-    // MARK: - Core Data Saving support
-    func saveContext () {
+    func saveContext () throws {
         let context = persistentContainer.viewContext
         if context.hasChanges {
             do {
                 try context.save()
             } catch {
-                let nserror = error as NSError
-                fatalError("Unresolved error \(nserror), \(nserror.userInfo)")
+                throw CoreDataError.saveFailure
             }
         }
     }

Diary/Error/CoreDataError.swift

@@ -0,0 +1,39 @@
+//
+//  CoreDataError.swift
+//  Diary
+//
+//  Created by Max, Hemg on 2023/09/10.
+//
+
+enum CoreDataError: Error {
+    case dataNotFound
+    case saveFailure
+    case deleteFailure
+    case unknown
+
+    var alertTitle: String {
+        switch self {
+        case .dataNotFound:
+            return "로드 실패"
+        case .saveFailure:
+            return "저장 실패"
+        case .deleteFailure:
+            return "삭제 실패"
+        case .unknown:
+            return "오류"
+        }
+    }
+
+    var message: String {
+        switch self {
+        case .dataNotFound:
+            return "데이터를 찾지 못했습니다."
+        case .saveFailure:
+            return "저장에 실패하였습니다."
+        case .deleteFailure:
+            return "삭제에 실패하였습니다."
+        case .unknown:
+            return "알 수 없는 오류입니다."
+        }
+    }
+}

Diary/Error/DecodingError.swift

@@ -2,7 +2,7 @@
 //  Error.swift
 //  Diary
 //
-//  Created by Min Hyun on 2023/08/30.
+//  Created by Max, Hemg on 2023/08/30.
 //
 
 enum DecodingError: Error {

Diary/Protocol/ShareDiary.swift → Diary/Protocol/ShareDisplayable.swift

@@ -7,11 +7,11 @@
 
 import UIKit
 
-protocol ShareDiary {
+protocol ShareDisplayable {
     func shareDiary(_ diary: Diary?)
 }
 
-extension ShareDiary where Self: UIViewController {
+extension ShareDisplayable where Self: UIViewController {
     func shareDiary(_ diary: Diary?) {
         guard let diary,
               let title = diary.title,