...

11 files changed, 604 insertions, 99 deletions

diff --git a/Timeline.Tests/UsernameValidatorUnitTest.cs b/Timeline.Tests/UsernameValidatorUnitTest.cs
index 9a80a3a2..283e18e2 100644
--- a/Timeline.Tests/UsernameValidatorUnitTest.cs
+++ b/Timeline.Tests/UsernameValidatorUnitTest.cs
@@ -1,6 +1,5 @@
 using FluentAssertions;

 using Timeline.Models.Validation;

-using Timeline.Tests.Mock.Services;

 using Xunit;

 

 namespace Timeline.Tests

@@ -16,15 +15,9 @@ namespace Timeline.Tests
 

         private string FailAndMessage(string username)

         {

-            var result = _validator.Validate(username, TestStringLocalizerFactory.Create(), out var message);

+            var (result, messageGenerator) = _validator.Validate(username);

             result.Should().BeFalse();

-            return message;

-        }

-

-        private void Succeed(string username)

-        {

-            _validator.Validate(username, TestStringLocalizerFactory.Create(), out var message).Should().BeTrue();

-            message.Should().Be(ValidationConstants.SuccessMessage);

+            return messageGenerator(null);

         }

 

         [Fact]

@@ -36,8 +29,9 @@ namespace Timeline.Tests
         [Fact]

         public void NotString()

         {

-            var result = _validator.Validate(123, TestStringLocalizerFactory.Create(), out var message);

+            var (result, messageGenerator) = _validator.Validate(123);

             result.Should().BeFalse();

+            var message = messageGenerator(null);

             message.Should().ContainEquivalentOf("type");

         }

 

@@ -47,31 +41,14 @@ namespace Timeline.Tests
             FailAndMessage("").Should().ContainEquivalentOf("empty");

         }

 

-        [Fact]

-        public void WhiteSpace()

+        [Theory]

+        [InlineData("!")]

+        [InlineData("!abc")]

+        [InlineData("ab c")]

+        public void BadCharactor(string value)

         {

-            FailAndMessage(" ").Should().ContainEquivalentOf("whitespace");

-            FailAndMessage("\t").Should().ContainEquivalentOf("whitespace");

-            FailAndMessage("\n").Should().ContainEquivalentOf("whitespace");

-

-            FailAndMessage("a b").Should().ContainEquivalentOf("whitespace");

-            FailAndMessage("a\tb").Should().ContainEquivalentOf("whitespace");

-            FailAndMessage("a\nb").Should().ContainEquivalentOf("whitespace");

-        }

-

-        [Fact]

-        public void BadCharactor()

-        {

-            FailAndMessage("!").Should().ContainEquivalentOf("regex");

-            FailAndMessage("!abc").Should().ContainEquivalentOf("regex");

-            FailAndMessage("ab!c").Should().ContainEquivalentOf("regex");

-        }

-

-        [Fact]

-        public void BadBegin()

-        {

-            FailAndMessage("-").Should().ContainEquivalentOf("regex");

-            FailAndMessage("-abc").Should().ContainEquivalentOf("regex");

+            FailAndMessage(value).Should().ContainEquivalentOf("invalid")

+                .And.ContainEquivalentOf("character");

         }

 

         [Fact]

@@ -80,14 +57,20 @@ namespace Timeline.Tests
             FailAndMessage(new string('a', 40)).Should().ContainEquivalentOf("long");

         }

 

-        [Fact]

-        public void Success()

+        [Theory]

+        [InlineData("abc")]

+        [InlineData("-abc")]

+        [InlineData("_abc")]

+        [InlineData("abc-")]

+        [InlineData("abc_")]

+        [InlineData("a-bc")]

+        [InlineData("a-b-c")]

+        [InlineData("a-b_c")]

+        public void Success(string value)

         {

-            Succeed("abc");

-            Succeed("_abc");

-            Succeed("a-bc");

-            Succeed("a-b-c");

-            Succeed("a-b_c");

+

+            var (result, _) = _validator.Validate(value);

+            result.Should().BeTrue();

         }

     }

 }

diff --git a/Timeline/Models/Validation/UsernameValidator.cs b/Timeline/Models/Validation/UsernameValidator.cs
index ecc3b5b3..65d4da71 100644
--- a/Timeline/Models/Validation/UsernameValidator.cs
+++ b/Timeline/Models/Validation/UsernameValidator.cs
@@ -1,46 +1,39 @@
-using Microsoft.Extensions.Localization;

-using System.Linq;

-using System.Text.RegularExpressions;

+using System.Linq;

 

 namespace Timeline.Models.Validation

 {

     public class UsernameValidator : Validator<string>

     {

         public const int MaxLength = 26;

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

 

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

-

-        protected override bool DoValidate(string value, IStringLocalizerFactory localizerFactory, out string message)

+        [System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1062:Validate arguments of public methods", Justification = "Already checked in base class.")]

+        protected override (bool, ValidationMessageGenerator) DoValidate(string value)

         {

             if (value.Length == 0)

             {

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

-                return false;

+                return (false, factory =>

+                    factory?.Create(typeof(UsernameValidator))?["ValidationMessageEmptyString"]

+                    ?? Resources.Models.Validation.UsernameValidator.InvariantValidationMessageEmptyString);

             }

 

             if (value.Length > 26)

             {

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

-                return false;

+                return (false, factory =>

+                    factory?.Create(typeof(UsernameValidator))?["ValidationMessageTooLong"]

+                    ?? Resources.Models.Validation.UsernameValidator.InvariantValidationMessageTooLong);

             }

 

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

-                if (char.IsWhiteSpace(c))

+            {

+                if (!(char.IsLetterOrDigit(c) || c == '-' || c == '_'))

                 {

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

-                    return false;

+                    return (false, factory =>

+                        factory?.Create(typeof(UsernameValidator))?["ValidationMessageInvalidChar"]

+                        ?? Resources.Models.Validation.UsernameValidator.InvariantValidationMessageInvalidChar);

                 }

-

-            var match = _regex.Match(value);

-            if (!match.Success)

-            {

-                message = "Regex match failed.";

-                return false;

             }

 

-            message = ValidationConstants.SuccessMessage;

-            return true;

+            return (true, SuccessMessageGenerator);

         }

     }

 }

diff --git a/Timeline/Models/Validation/Validator.cs b/Timeline/Models/Validation/Validator.cs
index a3800b71..606ba7b4 100644
--- a/Timeline/Models/Validation/Validator.cs
+++ b/Timeline/Models/Validation/Validator.cs
@@ -7,8 +7,15 @@ using Timeline.Helpers;
 namespace Timeline.Models.Validation

 {

     /// <summary>

+    /// Generate a message from a localizer factory.

+    /// If localizerFactory is null, it should return a neutral-cultural message.

+    /// </summary>

+    /// <param name="localizerFactory">The localizer factory. Could be null.</param>

+    /// <returns>The message.</returns>

+    public delegate string ValidationMessageGenerator(IStringLocalizerFactory? localizerFactory);

+

+    /// <summary>

     /// A validator to validate value.

-    /// See <see cref="Validate(object?, out string)"/>.

     /// </summary>

     public interface IValidator

     {

@@ -16,14 +23,8 @@ namespace Timeline.Models.Validation
         /// Validate given value.

         /// </summary>

         /// <param name="value">The value to validate.</param>

-        /// <param name="message">The validation message.</param>

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

-        bool Validate(object? value, IStringLocalizerFactory localizerFactory, out string message);

-    }

-

-    public static class ValidationConstants

-    {

-        public const string SuccessMessage = "Validation succeeded.";

+        /// <returns>Validation success or not and the message generator.</returns>

+        (bool, ValidationMessageGenerator) Validate(object? value);

     }

 

     /// <summary>

@@ -39,36 +40,32 @@ namespace Timeline.Models.Validation
     /// </remarks>

     public abstract class Validator<T> : IValidator

     {

-        [System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1062:Validate arguments of public methods", Justification = "<Pending>")]

-        public bool Validate(object? value, IStringLocalizerFactory localizerFactory, out string message)

+        public (bool, ValidationMessageGenerator) Validate(object? value)

         {

             if (value == null)

             {

-                var localizer = localizerFactory.Create("Models.Validation.Validator");

-                message = localizer["ValidatorMessageNull"];

-                return false;

+                return (false, factory =>

+                    factory?.Create("Models.Validation.Validator")?["ValidatorMessageNull"]

+                    ?? Resources.Models.Validation.Validator.InvariantValidatorMessageNull

+                );

             }

 

             if (value is T v)

             {

-                return DoValidate(v, localizerFactory, out message);

+                return DoValidate(v);

             }

             else

             {

-                var localizer = localizerFactory.Create("Models.Validation.Validator");

-                message = localizer["ValidatorMessageBadType", typeof(T).FullName];

-                return false;

+                return (false, factory =>

+                    factory?.Create("Models.Validation.Validator")?["ValidatorMessageBadType", typeof(T).FullName]

+                    ?? Resources.Models.Validation.Validator.InvariantValidatorMessageBadType);

             }

         }

 

-        [System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1062:Validate arguments of public methods")]

-        protected static string GetSuccessMessage(IStringLocalizerFactory factory)

-        {

-            var localizer = factory.Create("Models.Validation.Validator");

-            return localizer["ValidatorMessageSuccess"];

-        }

+        protected static ValidationMessageGenerator SuccessMessageGenerator { get; } = factory =>

+            factory?.Create("Models.Validation.Validator")?["ValidatorMessageSuccess"] ?? Resources.Models.Validation.Validator.InvariantValidatorMessageSuccess;

 

-        protected abstract bool DoValidate(T value, IStringLocalizerFactory localizerFactory, out string message);

+        protected abstract (bool, ValidationMessageGenerator) DoValidate(T value);

     }

 

     [AttributeUsage(AttributeTargets.Property | AttributeTargets.Field | AttributeTargets.Parameter,

@@ -113,11 +110,16 @@ namespace Timeline.Models.Validation
 

         protected override ValidationResult IsValid(object value, ValidationContext validationContext)

         {

-            var localizerFactory = validationContext.GetRequiredService<IStringLocalizerFactory>();

-            if (_validator.Validate(value, localizerFactory, out var message))

+            var (result, messageGenerator) = _validator.Validate(value);

+            if (result)

+            {

                 return ValidationResult.Success;

+            }

             else

-                return new ValidationResult(message);

+            {

+                var localizerFactory = validationContext.GetRequiredService<IStringLocalizerFactory>();

+                return new ValidationResult(messageGenerator(localizerFactory));

+            }

         }

     }

 }

diff --git a/Timeline/Resources/Models/Validation/UsernameValidator.Designer.cs b/Timeline/Resources/Models/Validation/UsernameValidator.Designer.cs
new file mode 100644
index 00000000..a4c35326
--- /dev/null
+++ b/Timeline/Resources/Models/Validation/UsernameValidator.Designer.cs
@@ -0,0 +1,90 @@
+//------------------------------------------------------------------------------

+// <auto-generated>

+//     This code was generated by a tool.

+//     Runtime Version:4.0.30319.42000

+//

+//     Changes to this file may cause incorrect behavior and will be lost if

+//     the code is regenerated.

+// </auto-generated>

+//------------------------------------------------------------------------------

+

+namespace Timeline.Resources.Models.Validation {

+    using System;

+    

+    

+    /// <summary>

+    ///   A strongly-typed resource class, for looking up localized strings, etc.

+    /// </summary>

+    // This class was auto-generated by the StronglyTypedResourceBuilder

+    // class via a tool like ResGen or Visual Studio.

+    // To add or remove a member, edit your .ResX file then rerun ResGen

+    // with the /str option, or rebuild your VS project.

+    [global::System.CodeDom.Compiler.GeneratedCodeAttribute("System.Resources.Tools.StronglyTypedResourceBuilder", "16.0.0.0")]

+    [global::System.Diagnostics.DebuggerNonUserCodeAttribute()]

+    [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()]

+    internal class UsernameValidator {

+        

+        private static global::System.Resources.ResourceManager resourceMan;

+        

+        private static global::System.Globalization.CultureInfo resourceCulture;

+        

+        [global::System.Diagnostics.CodeAnalysis.SuppressMessageAttribute("Microsoft.Performance", "CA1811:AvoidUncalledPrivateCode")]

+        internal UsernameValidator() {

+        }

+        

+        /// <summary>

+        ///   Returns the cached ResourceManager instance used by this class.

+        /// </summary>

+        [global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Advanced)]

+        internal static global::System.Resources.ResourceManager ResourceManager {

+            get {

+                if (object.ReferenceEquals(resourceMan, null)) {

+                    global::System.Resources.ResourceManager temp = new global::System.Resources.ResourceManager("Timeline.Resources.Models.Validation.UsernameValidator", typeof(UsernameValidator).Assembly);

+                    resourceMan = temp;

+                }

+                return resourceMan;

+            }

+        }

+        

+        /// <summary>

+        ///   Overrides the current thread's CurrentUICulture property for all

+        ///   resource lookups using this strongly typed resource class.

+        /// </summary>

+        [global::System.ComponentModel.EditorBrowsableAttribute(global::System.ComponentModel.EditorBrowsableState.Advanced)]

+        internal static global::System.Globalization.CultureInfo Culture {

+            get {

+                return resourceCulture;

+            }

+            set {

+                resourceCulture = value;

+            }

+        }

+        

+        /// <summary>

+        ///   Looks up a localized string similar to An empty string is not allowed..

+        /// </summary>

+        internal static string InvariantValidationMessageEmptyString {

+            get {

+                return ResourceManager.GetString("InvariantValidationMessageEmptyString", resourceCulture);

+            }

+        }

+        

+        /// <summary>

+        ///   Looks up a localized string similar to Invalid character, only alphabet, digit, underscore and hyphen are allowed. .

+        /// </summary>

+        internal static string InvariantValidationMessageInvalidChar {

+            get {

+                return ResourceManager.GetString("InvariantValidationMessageInvalidChar", resourceCulture);

+            }

+        }

+        

+        /// <summary>

+        ///   Looks up a localized string similar to Too long, more than 26 characters is not premitted..

+        /// </summary>

+        internal static string InvariantValidationMessageTooLong {

+            get {

+                return ResourceManager.GetString("InvariantValidationMessageTooLong", resourceCulture);

+            }

+        }

+    }

+}

diff --git a/Timeline/Resources/Models/Validation/UsernameValidator.en.resx b/Timeline/Resources/Models/Validation/UsernameValidator.en.resx
new file mode 100644
index 00000000..9171b856
--- /dev/null
+++ b/Timeline/Resources/Models/Validation/UsernameValidator.en.resx
@@ -0,0 +1,129 @@
+<?xml version="1.0" encoding="utf-8"?>

+<root>

+  <!-- 

+    Microsoft ResX Schema 

+    

+    Version 2.0

+    

+    The primary goals of this format is to allow a simple XML format 

+    that is mostly human readable. The generation and parsing of the 

+    various data types are done through the TypeConverter classes 

+    associated with the data types.

+    

+    Example:

+    

+    ... ado.net/XML headers & schema ...

+    <resheader name="resmimetype">text/microsoft-resx</resheader>

+    <resheader name="version">2.0</resheader>

+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>

+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>

+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>

+    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>

+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">

+        <value>[base64 mime encoded serialized .NET Framework object]</value>

+    </data>

+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">

+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>

+        <comment>This is a comment</comment>

+    </data>

+                

+    There are any number of "resheader" rows that contain simple 

+    name/value pairs.

+    

+    Each data row contains a name, and value. The row also contains a 

+    type or mimetype. Type corresponds to a .NET class that support 

+    text/value conversion through the TypeConverter architecture. 

+    Classes that don't support this are serialized and stored with the 

+    mimetype set.

+    

+    The mimetype is used for serialized objects, and tells the 

+    ResXResourceReader how to depersist the object. This is currently not 

+    extensible. For a given mimetype the value must be set accordingly:

+    

+    Note - application/x-microsoft.net.object.binary.base64 is the format 

+    that the ResXResourceWriter will generate, however the reader can 

+    read any of the formats listed below.

+    

+    mimetype: application/x-microsoft.net.object.binary.base64

+    value   : The object must be serialized with 

+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter

+            : and then encoded with base64 encoding.

+    

+    mimetype: application/x-microsoft.net.object.soap.base64

+    value   : The object must be serialized with 

+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter

+            : and then encoded with base64 encoding.

+

+    mimetype: application/x-microsoft.net.object.bytearray.base64

+    value   : The object must be serialized into a byte array 

+            : using a System.ComponentModel.TypeConverter

+            : and then encoded with base64 encoding.

+    -->

+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">

+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />

+    <xsd:element name="root" msdata:IsDataSet="true">

+      <xsd:complexType>

+        <xsd:choice maxOccurs="unbounded">

+          <xsd:element name="metadata">

+            <xsd:complexType>

+              <xsd:sequence>

+                <xsd:element name="value" type="xsd:string" minOccurs="0" />

+              </xsd:sequence>

+              <xsd:attribute name="name" use="required" type="xsd:string" />

+              <xsd:attribute name="type" type="xsd:string" />

+              <xsd:attribute name="mimetype" type="xsd:string" />

+              <xsd:attribute ref="xml:space" />

+            </xsd:complexType>

+          </xsd:element>

+          <xsd:element name="assembly">

+            <xsd:complexType>

+              <xsd:attribute name="alias" type="xsd:string" />

+              <xsd:attribute name="name" type="xsd:string" />

+            </xsd:complexType>

+          </xsd:element>

+          <xsd:element name="data">

+            <xsd:complexType>

+              <xsd:sequence>

+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />

+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />

+              </xsd:sequence>

+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />

+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />

+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />

+              <xsd:attribute ref="xml:space" />

+            </xsd:complexType>

+          </xsd:element>

+          <xsd:element name="resheader">

+            <xsd:complexType>

+              <xsd:sequence>

+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />

+              </xsd:sequence>

+              <xsd:attribute name="name" type="xsd:string" use="required" />

+            </xsd:complexType>

+          </xsd:element>

+        </xsd:choice>

+      </xsd:complexType>

+    </xsd:element>

+  </xsd:schema>

+  <resheader name="resmimetype">

+    <value>text/microsoft-resx</value>

+  </resheader>

+  <resheader name="version">

+    <value>2.0</value>

+  </resheader>

+  <resheader name="reader">

+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>

+  </resheader>

+  <resheader name="writer">

+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>

+  </resheader>

+  <data name="ValidationMessageEmptyString" xml:space="preserve">

+    <value>An empty string is not allowed.</value>

+  </data>

+  <data name="ValidationMessageInvalidChar" xml:space="preserve">

+    <value>Invalid character, only alphabet, digit, underscore and hyphen are allowed.</value>

+  </data>

+  <data name="ValidationMessageTooLong" xml:space="preserve">

+    <value>Too long, more than 26 characters is not premitted.</value>

+  </data>

+</root>
\ No newline at end of file
diff --git a/Timeline/Resources/Models/Validation/UsernameValidator.resx b/Timeline/Resources/Models/Validation/UsernameValidator.resx
new file mode 100644
index 00000000..80cae2d5
--- /dev/null
+++ b/Timeline/Resources/Models/Validation/UsernameValidator.resx
@@ -0,0 +1,129 @@
+<?xml version="1.0" encoding="utf-8"?>

+<root>

+  <!-- 

+    Microsoft ResX Schema 

+    

+    Version 2.0

+    

+    The primary goals of this format is to allow a simple XML format 

+    that is mostly human readable. The generation and parsing of the 

+    various data types are done through the TypeConverter classes 

+    associated with the data types.

+    

+    Example:

+    

+    ... ado.net/XML headers & schema ...

+    <resheader name="resmimetype">text/microsoft-resx</resheader>

+    <resheader name="version">2.0</resheader>

+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>

+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>

+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>

+    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>

+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">

+        <value>[base64 mime encoded serialized .NET Framework object]</value>

+    </data>

+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">

+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>

+        <comment>This is a comment</comment>

+    </data>

+                

+    There are any number of "resheader" rows that contain simple 

+    name/value pairs.

+    

+    Each data row contains a name, and value. The row also contains a 

+    type or mimetype. Type corresponds to a .NET class that support 

+    text/value conversion through the TypeConverter architecture. 

+    Classes that don't support this are serialized and stored with the 

+    mimetype set.

+    

+    The mimetype is used for serialized objects, and tells the 

+    ResXResourceReader how to depersist the object. This is currently not 

+    extensible. For a given mimetype the value must be set accordingly:

+    

+    Note - application/x-microsoft.net.object.binary.base64 is the format 

+    that the ResXResourceWriter will generate, however the reader can 

+    read any of the formats listed below.

+    

+    mimetype: application/x-microsoft.net.object.binary.base64

+    value   : The object must be serialized with 

+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter

+            : and then encoded with base64 encoding.

+    

+    mimetype: application/x-microsoft.net.object.soap.base64

+    value   : The object must be serialized with 

+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter

+            : and then encoded with base64 encoding.

+

+    mimetype: application/x-microsoft.net.object.bytearray.base64

+    value   : The object must be serialized into a byte array 

+            : using a System.ComponentModel.TypeConverter

+            : and then encoded with base64 encoding.

+    -->

+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">

+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />

+    <xsd:element name="root" msdata:IsDataSet="true">

+      <xsd:complexType>

+        <xsd:choice maxOccurs="unbounded">

+          <xsd:element name="metadata">

+            <xsd:complexType>

+              <xsd:sequence>

+                <xsd:element name="value" type="xsd:string" minOccurs="0" />

+              </xsd:sequence>

+              <xsd:attribute name="name" use="required" type="xsd:string" />

+              <xsd:attribute name="type" type="xsd:string" />

+              <xsd:attribute name="mimetype" type="xsd:string" />

+              <xsd:attribute ref="xml:space" />

+            </xsd:complexType>

+          </xsd:element>

+          <xsd:element name="assembly">

+            <xsd:complexType>

+              <xsd:attribute name="alias" type="xsd:string" />

+              <xsd:attribute name="name" type="xsd:string" />

+            </xsd:complexType>

+          </xsd:element>

+          <xsd:element name="data">

+            <xsd:complexType>

+              <xsd:sequence>

+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />

+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />

+              </xsd:sequence>

+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />

+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />

+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />

+              <xsd:attribute ref="xml:space" />

+            </xsd:complexType>

+          </xsd:element>

+          <xsd:element name="resheader">

+            <xsd:complexType>

+              <xsd:sequence>

+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />

+              </xsd:sequence>

+              <xsd:attribute name="name" type="xsd:string" use="required" />

+            </xsd:complexType>

+          </xsd:element>

+        </xsd:choice>

+      </xsd:complexType>

+    </xsd:element>

+  </xsd:schema>

+  <resheader name="resmimetype">

+    <value>text/microsoft-resx</value>

+  </resheader>

+  <resheader name="version">

+    <value>2.0</value>

+  </resheader>

+  <resheader name="reader">

+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>

+  </resheader>

+  <resheader name="writer">

+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>

+  </resheader>

+  <data name="InvariantValidationMessageEmptyString" xml:space="preserve">

+    <value>An empty string is not allowed.</value>

+  </data>

+  <data name="InvariantValidationMessageInvalidChar" xml:space="preserve">

+    <value>Invalid character, only alphabet, digit, underscore and hyphen are allowed. </value>

+  </data>

+  <data name="InvariantValidationMessageTooLong" xml:space="preserve">

+    <value>Too long, more than 26 characters is not premitted.</value>

+  </data>

+</root>
\ No newline at end of file
diff --git a/Timeline/Resources/Models/Validation/UsernameValidator.zh.resx b/Timeline/Resources/Models/Validation/UsernameValidator.zh.resx
new file mode 100644
index 00000000..1c8a936c
--- /dev/null
+++ b/Timeline/Resources/Models/Validation/UsernameValidator.zh.resx
@@ -0,0 +1,129 @@
+<?xml version="1.0" encoding="utf-8"?>

+<root>

+  <!-- 

+    Microsoft ResX Schema 

+    

+    Version 2.0

+    

+    The primary goals of this format is to allow a simple XML format 

+    that is mostly human readable. The generation and parsing of the 

+    various data types are done through the TypeConverter classes 

+    associated with the data types.

+    

+    Example:

+    

+    ... ado.net/XML headers & schema ...

+    <resheader name="resmimetype">text/microsoft-resx</resheader>

+    <resheader name="version">2.0</resheader>

+    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>

+    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>

+    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>

+    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>

+    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">

+        <value>[base64 mime encoded serialized .NET Framework object]</value>

+    </data>

+    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">

+        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>

+        <comment>This is a comment</comment>

+    </data>

+                

+    There are any number of "resheader" rows that contain simple 

+    name/value pairs.

+    

+    Each data row contains a name, and value. The row also contains a 

+    type or mimetype. Type corresponds to a .NET class that support 

+    text/value conversion through the TypeConverter architecture. 

+    Classes that don't support this are serialized and stored with the 

+    mimetype set.

+    

+    The mimetype is used for serialized objects, and tells the 

+    ResXResourceReader how to depersist the object. This is currently not 

+    extensible. For a given mimetype the value must be set accordingly:

+    

+    Note - application/x-microsoft.net.object.binary.base64 is the format 

+    that the ResXResourceWriter will generate, however the reader can 

+    read any of the formats listed below.

+    

+    mimetype: application/x-microsoft.net.object.binary.base64

+    value   : The object must be serialized with 

+            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter

+            : and then encoded with base64 encoding.

+    

+    mimetype: application/x-microsoft.net.object.soap.base64

+    value   : The object must be serialized with 

+            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter

+            : and then encoded with base64 encoding.

+

+    mimetype: application/x-microsoft.net.object.bytearray.base64

+    value   : The object must be serialized into a byte array 

+            : using a System.ComponentModel.TypeConverter

+            : and then encoded with base64 encoding.

+    -->

+  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">

+    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />

+    <xsd:element name="root" msdata:IsDataSet="true">

+      <xsd:complexType>

+        <xsd:choice maxOccurs="unbounded">

+          <xsd:element name="metadata">

+            <xsd:complexType>

+              <xsd:sequence>

+                <xsd:element name="value" type="xsd:string" minOccurs="0" />

+              </xsd:sequence>

+              <xsd:attribute name="name" use="required" type="xsd:string" />

+              <xsd:attribute name="type" type="xsd:string" />

+              <xsd:attribute name="mimetype" type="xsd:string" />

+              <xsd:attribute ref="xml:space" />

+            </xsd:complexType>

+          </xsd:element>

+          <xsd:element name="assembly">

+            <xsd:complexType>

+              <xsd:attribute name="alias" type="xsd:string" />

+              <xsd:attribute name="name" type="xsd:string" />

+            </xsd:complexType>

+          </xsd:element>

+          <xsd:element name="data">

+            <xsd:complexType>

+              <xsd:sequence>

+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />

+                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />

+              </xsd:sequence>

+              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />

+              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />

+              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />

+              <xsd:attribute ref="xml:space" />

+            </xsd:complexType>

+          </xsd:element>

+          <xsd:element name="resheader">

+            <xsd:complexType>

+              <xsd:sequence>

+                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />

+              </xsd:sequence>

+              <xsd:attribute name="name" type="xsd:string" use="required" />

+            </xsd:complexType>

+          </xsd:element>

+        </xsd:choice>

+      </xsd:complexType>

+    </xsd:element>

+  </xsd:schema>

+  <resheader name="resmimetype">

+    <value>text/microsoft-resx</value>

+  </resheader>

+  <resheader name="version">

+    <value>2.0</value>

+  </resheader>

+  <resheader name="reader">

+    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>

+  </resheader>

+  <resheader name="writer">

+    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>

+  </resheader>

+  <data name="ValidationMessageEmptyString" xml:space="preserve">

+    <value>空字符串是不允许的。</value>

+  </data>

+  <data name="ValidationMessageInvalidChar" xml:space="preserve">

+    <value>无效的字符，只能使用字母、数字、下划线和连字符。</value>

+  </data>

+  <data name="ValidationMessageTooLong" xml:space="preserve">

+    <value>太长了，不能大于26个字符。</value>

+  </data>

+</root>
\ No newline at end of file
diff --git a/Timeline/Resources/Models/Validation/Validator.Designer.cs b/Timeline/Resources/Models/Validation/Validator.Designer.cs
index f2532af3..4cbc13de 100644
--- a/Timeline/Resources/Models/Validation/Validator.Designer.cs
+++ b/Timeline/Resources/Models/Validation/Validator.Designer.cs
@@ -61,6 +61,33 @@ namespace Timeline.Resources.Models.Validation {
         }

         

         /// <summary>

+        ///   Looks up a localized string similar to Value is not of type {0}..

+        /// </summary>

+        internal static string InvariantValidatorMessageBadType {

+            get {

+                return ResourceManager.GetString("InvariantValidatorMessageBadType", resourceCulture);

+            }

+        }

+        

+        /// <summary>

+        ///   Looks up a localized string similar to Value can&apos;t be null..

+        /// </summary>

+        internal static string InvariantValidatorMessageNull {

+            get {

+                return ResourceManager.GetString("InvariantValidatorMessageNull", resourceCulture);

+            }

+        }

+        

+        /// <summary>

+        ///   Looks up a localized string similar to Validation succeeded..

+        /// </summary>

+        internal static string InvariantValidatorMessageSuccess {

+            get {

+                return ResourceManager.GetString("InvariantValidatorMessageSuccess", resourceCulture);

+            }

+        }

+        

+        /// <summary>

         ///   Looks up a localized string similar to Failed to create a validator instance from default constructor. See inner exception..

         /// </summary>

         internal static string ValidateWithAttributeCreateFail {

diff --git a/Timeline/Resources/Models/Validation/Validator.resx b/Timeline/Resources/Models/Validation/Validator.resx
index 8843dc42..0e8f53a6 100644
--- a/Timeline/Resources/Models/Validation/Validator.resx
+++ b/Timeline/Resources/Models/Validation/Validator.resx
@@ -117,6 +117,15 @@
   <resheader name="writer">

     <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>

   </resheader>

+  <data name="InvariantValidatorMessageBadType" xml:space="preserve">

+    <value>Value is not of type {0}.</value>

+  </data>

+  <data name="InvariantValidatorMessageNull" xml:space="preserve">

+    <value>Value can't be null.</value>

+  </data>

+  <data name="InvariantValidatorMessageSuccess" xml:space="preserve">

+    <value>Validation succeeded.</value>

+  </data>

   <data name="ValidateWithAttributeCreateFail" xml:space="preserve">

     <value>Failed to create a validator instance from default constructor. See inner exception.</value>

   </data>

diff --git a/Timeline/Services/UserService.cs b/Timeline/Services/UserService.cs
index aad4a806..45ef8a5c 100644
--- a/Timeline/Services/UserService.cs
+++ b/Timeline/Services/UserService.cs
@@ -140,16 +140,13 @@ namespace Timeline.Services
 

         private readonly UsernameValidator _usernameValidator;

 

-        private readonly IStringLocalizerFactory _localizerFactory;

-

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

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

         {

             _logger = logger;

             _memoryCache = memoryCache;

             _databaseContext = databaseContext;

             _jwtService = jwtService;

             _passwordService = passwordService;

-            _localizerFactory = localizerFactory;

 

             _usernameValidator = new UsernameValidator();

         }

@@ -244,9 +241,10 @@ namespace Timeline.Services
             if (password == null)

                 throw new ArgumentNullException(nameof(password));

 

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

+            var (result, messageGenerator) = _usernameValidator.Validate(username);

+            if (!result)

             {

-                throw new UsernameBadFormatException(username, message);

+                throw new UsernameBadFormatException(username, messageGenerator(null));

             }

 

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

@@ -353,8 +351,12 @@ namespace Timeline.Services
             if (string.IsNullOrEmpty(newUsername))

                 throw new ArgumentException("New username is null or empty", nameof(newUsername));

 

-            if (!_usernameValidator.Validate(newUsername, _localizerFactory, out var message))

-                throw new UsernameBadFormatException(newUsername, $"New username is of bad format. {message}");

+

+            var (result, messageGenerator) = _usernameValidator.Validate(newUsername);

+            if (!result)

+            {

+                throw new UsernameBadFormatException(newUsername, $"New username is of bad format. {messageGenerator(null)}");

+            }

 

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

             if (user == null)

diff --git a/Timeline/Timeline.csproj b/Timeline/Timeline.csproj
index d1f9b2ed..e29c4e4b 100644
--- a/Timeline/Timeline.csproj
+++ b/Timeline/Timeline.csproj
@@ -49,6 +49,11 @@
         <AutoGen>True</AutoGen>

         <DependentUpon>UserController.resx</DependentUpon>

       </Compile>

+      <Compile Update="Resources\Models\Validation\UsernameValidator.Designer.cs">

+        <DesignTime>True</DesignTime>

+        <AutoGen>True</AutoGen>

+        <DependentUpon>UsernameValidator.resx</DependentUpon>

+      </Compile>

       <Compile Update="Resources\Models\Validation\Validator.Designer.cs">

         <DesignTime>True</DesignTime>

         <AutoGen>True</AutoGen>

@@ -82,6 +87,13 @@
         <Generator>ResXFileCodeGenerator</Generator>

         <LastGenOutput>UserController.Designer.cs</LastGenOutput>

       </EmbeddedResource>

+      <EmbeddedResource Update="Resources\Models\Validation\UsernameValidator.resx">

+        <Generator>ResXFileCodeGenerator</Generator>

+        <LastGenOutput>UsernameValidator.Designer.cs</LastGenOutput>

+      </EmbeddedResource>

+      <EmbeddedResource Update="Resources\Models\Validation\Validator.en.resx">

+        <Generator></Generator>

+      </EmbeddedResource>

       <EmbeddedResource Update="Resources\Models\Validation\Validator.resx">

         <Generator>ResXFileCodeGenerator</Generator>

         <LastGenOutput>Validator.Designer.cs</LastGenOutput>