From 71c31c0bbb05d5085f76e4a7bb6cbaf584004475 Mon Sep 17 00:00:00 2001
From: Polianin Nikita <nikitkapolyanin@yandex.ru>
Date: Wed, 25 Dec 2024 05:46:27 +0300
Subject: [PATCH] refactor: separate the method of counting failed attempts

---
 Security/Services/AuthService.cs | 50 ++++++++++++++++++++------------
 1 file changed, 32 insertions(+), 18 deletions(-)

diff --git a/Security/Services/AuthService.cs b/Security/Services/AuthService.cs
index a505c09..17103e8 100644
--- a/Security/Services/AuthService.cs
+++ b/Security/Services/AuthService.cs
@@ -24,6 +24,7 @@ public class AuthService(ICacheService cache, IAccessToken accessTokenService, I
 
     private static string GetAuthCacheKey(string fingerprint) => $"{fingerprint}_auth_token";
     private static string GetFirstAuthCacheKey(string fingerprint) => $"{fingerprint}_auth_token_first";
+    private static string GetAttemptFailedCountKey(string fingerprint) => $"{fingerprint}_login_failed";
 
     private Task SetAuthTokenDataToCache(AuthToken data, CancellationToken cancellation) =>
         cache.SetAsync(
@@ -47,34 +48,47 @@ public class AuthService(ICacheService cache, IAccessToken accessTokenService, I
     private Task RevokeAccessToken(string token) =>
         revokedToken.AddTokenToRevokedAsync(token, accessTokenService.GetExpireDateTime(token));
 
-    private async Task VerifyUserOrThrowError(RequestContextInfo requestContext, User user, string password, string username,
-        CancellationToken cancellation = default)
+    private async Task RecordFailedLoginAttempt(string fingerprint, string userId, CancellationToken cancellation)
     {
-        if ((user.Email.Equals(username, StringComparison.OrdinalIgnoreCase) || user.Username.Equals(username, StringComparison.OrdinalIgnoreCase)) &&
-            passwordService.VerifyPassword(password, user.Salt, user.PasswordHash))
-            return;
+        var failedLoginAttemptsCount = await cache.GetAsync<int?>(GetAttemptFailedCountKey(fingerprint), cancellation) ?? 1;
+        var failedLoginCacheExpiration = TimeSpan.FromHours(1);
 
-        var failedLoginCacheName = $"{requestContext.Fingerprint}_login_failed";
-        var countFailedLogin = await cache.GetAsync<int?>(failedLoginCacheName, cancellation) ?? 1;
-        var cacheSaveTime = TimeSpan.FromHours(1);
-
-        await cache.SetAsync(failedLoginCacheName, countFailedLogin + 1, slidingExpiration: cacheSaveTime, cancellationToken: cancellation);
-
-        if (countFailedLogin > 5)
+        if (failedLoginAttemptsCount > 5)
         {
             logger.LogWarning(
-                "Multiple unsuccessful login attempts for user ID {UserId}. Attempt count: {AttemptNumber}.",
-                user.Id,
-                countFailedLogin);
+                "Multiple unsuccessful login attempts for user ID {UserId}. Fingerprint: {Fingerprint}. Attempt count: {AttemptNumber}.",
+                userId,
+                fingerprint,
+                failedLoginAttemptsCount);
 
             throw new SecurityException("Too many unsuccessful login attempts. Please try again later.");
         }
 
         logger.LogInformation(
             "Login attempt failed for user ID {UserId}. Fingerprint: {Fingerprint}. Attempt count: {AttemptNumber}.",
-            user.Id,
-            requestContext.Fingerprint,
-            countFailedLogin);
+            userId,
+            fingerprint,
+            failedLoginAttemptsCount);
+
+        await cache.SetAsync(GetAttemptFailedCountKey(fingerprint), failedLoginAttemptsCount + 1,
+            slidingExpiration: failedLoginCacheExpiration, cancellationToken: cancellation);
+    }
+
+    private Task ResetFailedLoginAttempts(string fingerprint, CancellationToken cancellation) =>
+        cache.RemoveAsync(GetAttemptFailedCountKey(fingerprint), cancellation);
+
+    private async Task VerifyUserOrThrowError(RequestContextInfo requestContext, User user, string password, string username,
+        CancellationToken cancellation = default)
+    {
+        if ((user.Email.Equals(username, StringComparison.OrdinalIgnoreCase) ||
+             user.Username.Equals(username, StringComparison.OrdinalIgnoreCase)) &&
+            passwordService.VerifyPassword(password, user.Salt, user.PasswordHash))
+        {
+            await ResetFailedLoginAttempts(requestContext.Fingerprint, cancellation);
+            return;
+        }
+
+        await RecordFailedLoginAttempt(requestContext.Fingerprint, user.Id, cancellation);
 
         throw new SecurityException("Authentication failed. Please check your credentials.");
     }