[#251] 여러 계정을 링크한 이후 각 공급자에 대한 실질적인 회원탈퇴가 이루어지지 않는 이슈를 해결한다 (#252)

* fix: 여러 공급자가 링크된 유저인 경우 providers를 순회해서 링크를 끉도록 해결

* refactor: providerIDs가 currentUser가 nil인 경우 빈 배열을 반환하도록 개선

* refactor: uid를 클라이언트 쪽에서 보내지 않도록 개선

* refactor: FCM 토큰을 삭제하는데 실패해도 로그아웃은 되도록 개선

Author: opficdev

DevLog/Data/Repository/AuthDataRepositoryImpl.swift

@@ -33,7 +33,7 @@ final class AuthDataRepositoryImpl: AuthDataRepository {
     }
 
     func fetchAllProviders() async throws -> [AuthProvider] {
-        let providerStrings = authService.providerIDs ?? []
+        let providerStrings = authService.providerIDs
         return providerStrings.compactMap { AuthProvider(rawValue: $0) }
     }
 

DevLog/Data/Repository/AuthenticationRepositoryImpl.swift

@@ -63,20 +63,25 @@ final class AuthenticationRepositoryImpl: AuthenticationRepository {
     }
 
     func delete() async throws {
-        guard let uid = authService.uid,
-              let providerID = try await authService.getProviderID(),
-              let provider = AuthProvider(rawValue: providerID)
-        else {
+        guard let uid = authService.uid else {
             throw AuthError.notAuthenticated
         }
 
-        switch provider {
-        case .apple:
-            try await appleAuthService.deleteAuth(uid)
-        case .github:
-            try await githubAuthService.deleteAuth(uid)
-        case .google:
-            try await googleAuthService.deleteAuth(uid)
+        let providers = authService.providerIDs.compactMap { AuthProvider(rawValue: $0) }
+
+        for provider in providers {
+            switch provider {
+            case .apple:
+                try await appleAuthService.deleteAuth(uid)
+            case .github:
+                try await githubAuthService.deleteAuth(uid)
+            case .google:
+                try await googleAuthService.deleteAuth(uid)
+            }
         }
+
+        try await authService.deleteFirestoreUserData()
+        try await authService.deleteCurrentUser()
+        try await authService.clearCurrentSession()
     }
 }

DevLog/Infra/Service/AuthService.swift

@@ -7,17 +7,21 @@
 
 import FirebaseAuth
 import FirebaseFirestore
+import FirebaseFunctions
+import FirebaseMessaging
 
 final class AuthService {
     private let store = Firestore.firestore()
+    private let functions = Functions.functions(region: "asia-northeast3")
+    private let messaging = Messaging.messaging()
     private let logger = Logger(category: "AuthService")
 
     var uid: String? {
         Auth.auth().currentUser?.uid
     }
 
-    var providerIDs: [String]? {
-        Auth.auth().currentUser?.providerData.map { $0.providerID }
+    var providerIDs: [String] {
+        Auth.auth().currentUser?.providerData.map { $0.providerID } ?? []
     }
 
     func getProviderID() async throws -> String? {
@@ -42,4 +46,33 @@ final class AuthService {
             throw error
         }
     }
+
+    func deleteFirestoreUserData() async throws {
+        logger.info("Deleting Firestore user data")
+
+        let deleteFunction = functions.httpsCallable("deleteUserFirestoreData")
+        _ = try await deleteFunction.call()
+    }
+
+    func deleteCurrentUser() async throws {
+        logger.info("Deleting FirebaseAuth current user")
+
+        guard let currentUser = Auth.auth().currentUser else {
+            logger.warning("No current user to delete")
+            throw AuthError.notAuthenticated
+        }
+
+        try await currentUser.delete()
+    }
+
+    func clearCurrentSession() async throws {
+        logger.info("Clearing current auth session")
+
+        do {
+            try await messaging.deleteToken()
+        } catch {
+            logger.error("Failed to delete FCM token while clearing session", error: error)
+        }
+        try Auth.auth().signOut()
+    }
 }

DevLog/Infra/Service/SocialLogin/AppleAuthenticationService.swift

@@ -105,14 +105,6 @@ final class AppleAuthenticationService: AuthenticationService {
         let token = try await refreshAppleAccessToken()
 
         try await revokeAppleAccessToken(token: token)
-
-        let deleteFunction = functions.httpsCallable("deleteUserFirestoreData")
-
-        _ = try await deleteFunction.call(["uid": uid])
-
-        try await user?.delete()
-        try await messaging.deleteToken()
-        try Auth.auth().signOut()
     }
 
     func link(uid: String, email: String) async throws {

DevLog/Infra/Service/SocialLogin/GithubAuthenticationService.swift

@@ -82,14 +82,6 @@ final class GithubAuthenticationService: NSObject, AuthenticationService {
 
     func deleteAuth(_ uid: String) async throws {
         try await revokeAccessToken()
-
-        let deleteFunction = functions.httpsCallable("deleteUserFirestoreData")
-
-        _ = try await deleteFunction.call(["uid": uid])
-
-        try await user?.delete()
-        try await messaging.deleteToken()
-        try Auth.auth().signOut()
     }
 
     func link(uid: String, email: String) async throws {

DevLog/Infra/Service/SocialLogin/GoogleAuthenticationService.swift

@@ -78,15 +78,8 @@ final class GoogleAuthenticationService: AuthenticationService {
     }
 
     func deleteAuth(_ uid: String) async throws {
-        let deleteFunction = functions.httpsCallable("deleteUserFirestoreData")
-
-        _ = try await deleteFunction.call(["uid": uid])
-
-        try await user?.delete()
         GIDSignIn.sharedInstance.signOut()
         try await GIDSignIn.sharedInstance.disconnect()
-        try await messaging.deleteToken()
-        try Auth.auth().signOut()
     }
 
     func link(uid: String, email: String) async throws {

Firebase/functions/src/user/delete.ts

@@ -1,15 +1,21 @@
 import { onCall, HttpsError } from "firebase-functions/v2/https";
 import * as admin from "firebase-admin";
+import * as logger from "firebase-functions/logger";
 
 export const deleteUserFirestoreData = onCall({
         cors: true,
         maxInstances: 10,
         region: "asia-northeast3"
     },
     async (request) => {
-        if (!request.auth) throw new HttpsError("unauthenticated", "로그인 필요");
-        const uid = request.data.uid;
-        if (!uid) throw new HttpsError("invalid-argument", "uid 필요");
+        if (!request.auth?.uid) {
+            logger.error("deleteUserFirestoreData called without authenticated uid", {
+                auth: request.auth ?? null
+            });
+            throw new HttpsError("unauthenticated", "로그인 필요");
+        }
+
+        const uid = request.auth.uid;
 
         try {
             const userDocRef = admin.firestore().doc(`users/${uid}`);