Merge pull request #40 from crupest/format

Add username format check.

2 files changed, 102 insertions, 14 deletions

diff --git a/Timeline/Controllers/UserController.cs b/Timeline/Controllers/UserController.cs
index 6f2fe77f..d38f96e1 100644
--- a/Timeline/Controllers/UserController.cs
+++ b/Timeline/Controllers/UserController.cs
@@ -18,9 +18,11 @@ namespace Timeline.Controllers
         {

             public const int Get_NotExist = -1001;

 

-            public const int Patch_NotExist = -2001;

+            public const int Put_BadUsername = -2001;

 

-            public const int ChangePassword_BadOldPassword = -3001;

+            public const int Patch_NotExist = -3001;

+

+            public const int ChangePassword_BadOldPassword = -4001;

         }

 

         private readonly ILogger<UserController> _logger;

@@ -53,17 +55,25 @@ namespace Timeline.Controllers
         [HttpPut("users/{username}"), AdminAuthorize]

         public async Task<IActionResult> Put([FromBody] UserPutRequest request, [FromRoute] string username)

         {

-            var result = await _userService.PutUser(username, request.Password, request.Administrator.Value);

-            switch (result)

+            try

+            {

+                var result = await _userService.PutUser(username, request.Password, request.Administrator.Value);

+                switch (result)

+                {

+                    case PutResult.Created:

+                        _logger.LogInformation(FormatLogMessage("A user is created.", Pair("Username", username)));

+                        return CreatedAtAction("Get", new { username }, CommonPutResponse.Created);

+                    case PutResult.Modified:

+                        _logger.LogInformation(FormatLogMessage("A user is modified.", Pair("Username", username)));

+                        return Ok(CommonPutResponse.Modified);

+                    default:

+                        throw new Exception("Unreachable code.");

+                }

+            }

+            catch (UsernameBadFormatException e)

             {

-                case PutResult.Created:

-                    _logger.LogInformation(FormatLogMessage("A user is created.", Pair("Username", username)));

-                    return CreatedAtAction("Get", new { username }, CommonPutResponse.Created);

-                case PutResult.Modified:

-                    _logger.LogInformation(FormatLogMessage("A user is modified.", Pair("Username", username)));

-                    return Ok(CommonPutResponse.Modified);

-                default:

-                    throw new Exception("Unreachable code.");

+                _logger.LogInformation(e, FormatLogMessage("Attempt to create a user with bad username failed.", Pair("Username", username)));

+                return BadRequest(new CommonResponse(ErrorCodes.Put_BadUsername, "Username is of bad format."));

             }

         }

 

diff --git a/Timeline/Services/UserService.cs b/Timeline/Services/UserService.cs
index 28218612..0993d3dc 100644
--- a/Timeline/Services/UserService.cs
+++ b/Timeline/Services/UserService.cs
@@ -3,6 +3,7 @@ using Microsoft.Extensions.Caching.Memory;
 using Microsoft.Extensions.Logging;

 using System;

 using System.Linq;

+using System.Text.RegularExpressions;

 using System.Threading.Tasks;

 using Timeline.Entities;

 using Timeline.Models;

@@ -102,6 +103,74 @@ namespace Timeline.Services
         public long RequiredVersion { get; private set; }

     }

 

+    /// <summary>

+    /// Thrown when username is of bad format.

+    /// </summary>

+    [Serializable]

+    public class UsernameBadFormatException : Exception

+    {

+        public UsernameBadFormatException(string username, string message) : base(message) { Username = username; }

+        public UsernameBadFormatException(string username, string message, Exception inner) : base(message, inner) { Username = username; }

+        protected UsernameBadFormatException(

+          System.Runtime.Serialization.SerializationInfo info,

+          System.Runtime.Serialization.StreamingContext context) : base(info, context) { }

+

+        /// <summary>

+        /// Username of bad format.

+        /// </summary>

+        public string Username { get; private set; }

+    }

+

+    public class UsernameValidator

+    {

+        public const int MaxLength = 26;

+        public const string RegexPattern = @"^[a-zA-Z0-9_][a-zA-Z0-9-_]*$";

+

+        private readonly Regex _regex = new Regex(RegexPattern);

+

+        /// <summary>

+        /// Validate a username.

+        /// </summary>

+        /// <param name="username">The username. Can't be null.</param>

+        /// <param name="message">Set as error message if there is error. Or null if no error.</param>

+        /// <returns>True if validation passed. Otherwise false.</returns>

+        /// <exception cref="ArgumentNullException">Thrown when <paramref name="username"/> is null.</exception>

+        public bool Validate(string username, out string message)

+        {

+            if (username == null)

+                throw new ArgumentNullException(nameof(username));

+

+            if (username.Length == 0)

+            {

+                message = "An empty string is not permitted.";

+                return false;

+            }

+

+            if (username.Length > 26)

+            {

+                message = $"Too long, more than 26 characters is not premitted, found {username.Length}.";

+                return false;

+            }

+

+            foreach ((char c, int i) in username.Select((c, i) => (c, i)))

+                if (char.IsWhiteSpace(c))

+                {

+                    message = $"A whitespace is found at {i} . Whitespace is not permited.";

+                    return false;

+                }

+

+            var match = _regex.Match(username);

+            if (!match.Success)

+            {

+                message = "Regex match failed.";

+                return false;

+            }

+

+            message = null;

+            return true;

+        }

+    }

+

     public interface IUserService

     {

         /// <summary>

@@ -144,14 +213,14 @@ namespace Timeline.Services
 

         /// <summary>

         /// Create or modify a user with given username.

-        /// Return <see cref="PutUserResult.Created"/> if a new user is created.

-        /// Return <see cref="PutUserResult.Modified"/> if a existing user is modified.

+        /// Username must be match with [a-zA-z0-9-_].

         /// </summary>

         /// <param name="username">Username of user.</param>

         /// <param name="password">Password of user.</param>

         /// <param name="administrator">Whether the user is administrator.</param>

         /// <returns>Return <see cref="PutResult.Created"/> if a new user is created.

         /// Return <see cref="PutResult.Modified"/> if a existing user is modified.</returns>

+        /// <exception cref="UsernameBadFormatException">Thrown when <paramref name="username"/> is of bad format.</exception>

         /// <exception cref="ArgumentNullException">Thrown when <paramref name="username"/> or <paramref name="password"/> is null.</exception>

         Task<PutResult> PutUser(string username, string password, bool administrator);

 

@@ -209,6 +278,8 @@ namespace Timeline.Services
         private readonly IJwtService _jwtService;

         private readonly IPasswordService _passwordService;

 

+        private readonly UsernameValidator _usernameValidator;

+

         public UserService(ILogger<UserService> logger, IMemoryCache memoryCache, DatabaseContext databaseContext, IJwtService jwtService, IPasswordService passwordService)

         {

             _logger = logger;

@@ -216,6 +287,8 @@ namespace Timeline.Services
             _databaseContext = databaseContext;

             _jwtService = jwtService;

             _passwordService = passwordService;

+

+            _usernameValidator = new UsernameValidator();

         }

 

         private string GenerateCacheKeyByUserId(long id) => $"user:{id}";

@@ -308,6 +381,11 @@ namespace Timeline.Services
             if (password == null)

                 throw new ArgumentNullException(nameof(password));

 

+            if (!_usernameValidator.Validate(username, out var message))

+            {

+                throw new UsernameBadFormatException(username, message);

+            }

+

             var user = await _databaseContext.Users.Where(u => u.Name == username).SingleOrDefaultAsync();

 

             if (user == null)