CMS Kit: Cache generated reCaptcha result

modules/cms-kit/src/Volo.CmsKit.Public.Web/Controllers/CmsKitPublicCommentsController.cs

@@ -37,7 +37,7 @@ public class CmsKitPublicCommentsController : CmsKitPublicControllerBase
         {
             CheckCaptchaTokenNullity(input.CaptchaToken);
 
-            SimpleMathsCaptchaGenerator.Validate(input.CaptchaToken.Value, input.CaptchaAnswer);
+            await SimpleMathsCaptchaGenerator.ValidateAsync(input.CaptchaToken.Value, input.CaptchaAnswer);
         }
 
         var dto = ObjectMapper.Map<CreateCommentWithParametersInput, CreateCommentInput> (input);
@@ -51,7 +51,7 @@ public class CmsKitPublicCommentsController : CmsKitPublicControllerBase
         {
             CheckCaptchaTokenNullity(input.CaptchaToken);
 
-            SimpleMathsCaptchaGenerator.Validate(input.CaptchaToken.Value, input.CaptchaAnswer);
+            await SimpleMathsCaptchaGenerator.ValidateAsync(input.CaptchaToken.Value, input.CaptchaAnswer);
         }
         
         await CommentPublicAppService.UpdateAsync(id, input);

modules/cms-kit/src/Volo.CmsKit.Public.Web/Pages/CmsKit/Shared/Components/Commenting/CommentingViewComponent.cs

@@ -76,26 +76,30 @@ public class CommentingViewComponent : AbpViewComponent
             LoginUrl = loginUrl,
             Comments = comments.OrderByDescending(i => i.CreationTime).ToList()
         };
+
         await ConvertMarkdownTextsToHtml(viewModel);
 
         if (CmsKitCommentOptions.IsRecaptchaEnabled)
         {
-            CaptchaOutput = GetCaptcha();
+            CaptchaOutput = await GenerateCaptchaAsync();
 
             viewModel.CaptchaImageBase64 = GetCaptchaImageBase64(CaptchaOutput.ImageBytes);
         }
+
         this.Input = viewModel;
         return View("~/Pages/CmsKit/Shared/Components/Commenting/Default.cshtml", this);
     }
 
-    public CaptchaOutput GetCaptcha()
+    public async Task<CaptchaOutput> GenerateCaptchaAsync()
     {
-        return SimpleMathsCaptchaGenerator.Generate(new CaptchaOptions(
+        return await SimpleMathsCaptchaGenerator.GenerateAsync(
+            new CaptchaOptions(
                 number1MinValue: 1,
                 number1MaxValue: 10,
                 number2MinValue: 5,
-                number2MaxValue: 15)
-            );
+                number2MaxValue: 15
+            )
+        );
     }
     
     public string GetCaptchaImageBase64(byte[] bytes)

modules/cms-kit/src/Volo.CmsKit.Public.Web/Pages/CmsKit/Shared/Components/Commenting/Default.cshtml

@@ -133,7 +133,8 @@
 
                     @if (CmsKitCommentOptions.Value.IsRecaptchaEnabled)
                     {
-                        var output = Model.GetCaptcha();
+                        var output = await Model.GenerateCaptchaAsync();
+
                         <div class="volo-captcha">
                             <label class="form-label" for="Input_Captcha_@output.Id">@L["CaptchaCode"]</label>
                             <div class="d-flex">

modules/cms-kit/src/Volo.CmsKit.Public.Web/Security/Captcha/CaptchaOptions.cs

@@ -1,4 +1,5 @@
-using SixLabors.Fonts;
+using System;
+using SixLabors.Fonts;
 using SixLabors.ImageSharp;
 using SixLabors.ImageSharp.Formats;
 
@@ -47,6 +48,8 @@ public class CaptchaOptions
 
     public int Number2MaxValue { get; set; } = 99;
 
+    public TimeSpan DurationOfValidity { get; set; } = TimeSpan.FromMinutes(10);
+
     public CaptchaOptions()
     {
 

modules/cms-kit/src/Volo.CmsKit.Public.Web/Security/Captcha/SimpleMathsCaptchaGenerator.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Numerics;
@@ -15,27 +14,30 @@ using Microsoft.Extensions.Localization;
 using Volo.Abp.DependencyInjection;
 using Color = SixLabors.ImageSharp.Color;
 using PointF = SixLabors.ImageSharp.PointF;
+using Volo.Abp.Caching;
+using Microsoft.Extensions.Caching.Distributed;
 
 namespace Volo.CmsKit.Public.Web.Security.Captcha;
 
-public class SimpleMathsCaptchaGenerator : ISingletonDependency
+public class SimpleMathsCaptchaGenerator : ITransientDependency
 {
-    private readonly IStringLocalizer<CmsKitResource> _localizer;
+    protected IStringLocalizer<CmsKitResource> Localizer { get; }
+    protected IDistributedCache<CaptchaOutput> Cache { get; }
 
-    public SimpleMathsCaptchaGenerator(IStringLocalizer<CmsKitResource> localizer)
+    public SimpleMathsCaptchaGenerator(IStringLocalizer<CmsKitResource> localizer, IDistributedCache<CaptchaOutput> cache)
     {
-        _localizer = localizer;
+        Localizer = localizer;
+        Cache = cache;
     }
-    private static Dictionary<Guid, CaptchaRequest> Session { get; set; } = new Dictionary<Guid, CaptchaRequest>();
 
-    public CaptchaOutput Generate()
+    public virtual Task<CaptchaOutput> GenerateAsync()
     {
-        return Generate(options: null, number1: null, number2: null);
+        return GenerateAsync(options: null, number1: null, number2: null);
     }
 
-    public CaptchaOutput Generate(CaptchaOptions options)
+    public virtual Task<CaptchaOutput> GenerateAsync(CaptchaOptions options)
     {
-        return Generate(options, number1: null, number2: null);
+        return GenerateAsync(options, number1: null, number2: null);
     }
 
     /// <summary>
@@ -45,7 +47,7 @@ public class SimpleMathsCaptchaGenerator : ISingletonDependency
     /// <param name="number1">First number for maths operation</param>
     /// <param name="number2">Second number for maths operation</param>
     /// <returns></returns>
-    public CaptchaOutput Generate(CaptchaOptions options, int? number1, int? number2)
+    public virtual async Task<CaptchaOutput> GenerateAsync(CaptchaOptions options, int? number1, int? number2)
     {
         var random = new Random();
         options ??= new CaptchaOptions();
@@ -65,11 +67,15 @@ public class SimpleMathsCaptchaGenerator : ISingletonDependency
             {
                 Text = text,
                 Result = Calculate(number1.Value, number2.Value),
-                ImageBytes =  GenerateInternal(text, options)
+                ImageBytes = GenerateInternal(text, options)
             }
         };
 
-        Session[request.Output.Id] = request;
+        await Cache.SetAsync(request.Output.Id.ToString("N"), request.Output, new DistributedCacheEntryOptions 
+        {
+            AbsoluteExpiration = DateTimeOffset.Now.Add(options.DurationOfValidity)
+        });
+
         return request.Output;
     }
 
@@ -78,24 +84,25 @@ public class SimpleMathsCaptchaGenerator : ISingletonDependency
         return number1 + number2;
     }
 
-    public void Validate(Guid requestId, int value)
+    public virtual async Task ValidateAsync(Guid requestId, int value)
     {
-        var request = Session[requestId];
-        if (request.Output.Result != value)
+        var request = await Cache.GetAsync(requestId.ToString("N"));
+        
+        if(request == null || request.Result != value) 
         {
-            throw new UserFriendlyException(_localizer["CaptchaCodeErrorMessage"]);
+            throw new UserFriendlyException(Localizer["CaptchaCodeErrorMessage"]);
         }
     }
 
-    public void Validate(Guid requestId, string value)
+    public virtual async Task ValidateAsync(Guid requestId, string value)
     {
         if (int.TryParse(value, out var captchaInput))
         {
-            Validate(requestId, captchaInput);
+            await ValidateAsync(requestId, captchaInput);
         }
         else
         {
-            throw new UserFriendlyException(_localizer["CaptchaCodeMissingMessage"]);
+            throw new UserFriendlyException(Localizer["CaptchaCodeMissingMessage"]);
         }
     }