3 files changed, 41 insertions, 6 deletions
diff --git a/Timeline/Services/Clock.cs b/Timeline/Services/Clock.cs
new file mode 100644
index 00000000..98451ad9
--- /dev/null
+++ b/Timeline/Services/Clock.cs
@@ -0,0 +1,32 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+namespace Timeline.Services
+{
+    /// <summary>
+    /// Convenient for unit test.
+    /// </summary>
+    public interface IClock
+    {
+        /// <summary>
+        /// Get current time.
+        /// </summary>
+        /// <returns>Current time.</returns>
+        DateTime GetCurrentTime();
+    }
+
+    public class Clock : IClock
+    {
+        public Clock()
+        {
+
+        }
+
+        public DateTime GetCurrentTime()
+        {
+            return DateTime.Now;
+        }
+    }
+}
diff --git a/Timeline/Services/JwtService.cs b/Timeline/Services/JwtService.cs
index f3416cce..52e892f6 100644
--- a/Timeline/Services/JwtService.cs
+++ b/Timeline/Services/JwtService.cs
@@ -94,10 +94,12 @@ namespace Timeline.Services
 
         private readonly IOptionsMonitor<JwtConfig> _jwtConfig;
         private readonly JwtSecurityTokenHandler _tokenHandler = new JwtSecurityTokenHandler();
+        private readonly IClock _clock;
 
-        public JwtService(IOptionsMonitor<JwtConfig> jwtConfig)
+        public JwtService(IOptionsMonitor<JwtConfig> jwtConfig, IClock clock)
         {
             _jwtConfig = jwtConfig;
+            _clock = clock;
         }
 
         public string GenerateJwtToken(TokenInfo tokenInfo, DateTime? expires = null)
@@ -118,8 +120,8 @@ namespace Timeline.Services
                 Audience = config.Audience,
                 SigningCredentials = new SigningCredentials(
                     new SymmetricSecurityKey(Encoding.ASCII.GetBytes(config.SigningKey)), SecurityAlgorithms.HmacSha384),
-                IssuedAt = DateTime.Now,
-                Expires = expires.GetValueOrDefault(DateTime.Now.AddSeconds(config.DefaultExpireOffset))
+                IssuedAt = _clock.GetCurrentTime(),
+                Expires = expires.GetValueOrDefault(_clock.GetCurrentTime().AddSeconds(config.DefaultExpireOffset))
             };
 
             var token = _tokenHandler.CreateToken(tokenDescriptor);
diff --git a/Timeline/Services/UserService.cs b/Timeline/Services/UserService.cs
index 3164a645..328dbff0 100644
--- a/Timeline/Services/UserService.cs
+++ b/Timeline/Services/UserService.cs
@@ -58,11 +58,12 @@ namespace Timeline.Services
         /// </summary>
         /// <param name="username">The username of the user to anthenticate.</param>
         /// <param name="password">The password of the user to anthenticate.</param>
+        /// <param name="expires">The expired time point. Null then use default. See <see cref="JwtService.GenerateJwtToken(TokenInfo, DateTime?)"/> for what is default.</param>
         /// <returns>An <see cref="CreateTokenResult"/> containing the created token and user info.</returns>
         /// <exception cref="ArgumentNullException">Thrown when <paramref name="username"/> or <paramref name="password"/> is null.</exception>
         /// <exception cref="UserNotExistException">Thrown when the user with given username does not exist.</exception>
         /// <exception cref="BadPasswordException">Thrown when password is wrong.</exception>
-        Task<CreateTokenResult> CreateToken(string username, string password);
+        Task<CreateTokenResult> CreateToken(string username, string password, DateTime? expires = null);
 
         /// <summary>
         /// Verify the given token.
@@ -170,7 +171,7 @@ namespace Timeline.Services
             _memoryCache.Remove(GenerateCacheKeyByUserId(id));
         }
 
-        public async Task<CreateTokenResult> CreateToken(string username, string password)
+        public async Task<CreateTokenResult> CreateToken(string username, string password, DateTime? expires)
         {
             if (username == null)
                 throw new ArgumentNullException(nameof(username));
@@ -198,7 +199,7 @@ namespace Timeline.Services
             {
                 Id = user.Id,
                 Version = user.Version
-            });
+            }, expires);
             return new CreateTokenResult
             {
                 Token = token,