YMJake.FusionCaptcha.Storage.Redis 1.0.0

FusionCaptcha

FusionCaptcha is a .NET captcha toolkit built on top of the Vello rendering pipeline. It focuses on three core responsibilities—code generation, image rendering, and persistence—while leaving fonts, backgrounds, and other resources entirely in the hands of your application. This keeps the library lightweight and easy to integrate into Web API, Minimal API, or background services.

Packages

Installation

dotnet add package YMJake.FusionCaptcha.Core
dotnet add package YMJake.FusionCaptcha.Storage.Memory
# or
dotnet add package YMJake.FusionCaptcha.Storage.Redis

Vello’s native dependencies (vello_ffi.dll, etc.) are shipped transitively via NuGet. Ensure your runtime RID is supported by Vello.

Quick Start (ASP.NET Core)

using YMJake.CaptchaSharp.Abstractions;
using YMJake.CaptchaSharp.Core;
using YMJake.CaptchaSharp.Storage.Memory;

var builder = WebApplication.CreateBuilder(args);

builder.Services
    .AddCaptcha(options =>
    {
        options.Image.Width = 160;
        options.Image.Height = 60;
        options.Image.FontSize = 36;
        options.Image.FontFamily = "ActionJ";
        options.Image.BackgroundImage = "Grid";
    })
    .UseFileResources(resources =>
    {
        resources.Fonts.BasePath = Path.Combine(builder.Environment.ContentRootPath, "Resources", "Fonts");
        resources.Fonts.AddFont("actionj.ttf", "ActionJ");

        resources.Backgrounds.BasePath = Path.Combine(builder.Environment.ContentRootPath, "Resources", "Backgrounds");
        resources.Backgrounds.AddBackground("grid.png", "Grid");
    })
    .UseVelloRenderer()
    .UseCaptchaMemoryStorage();

var app = builder.Build();

app.MapGet("/captcha", async (string id, ICaptcha captcha) =>
{
    var result = await captcha.GenerateAsync(id);
    return Results.File(result.Bytes, result.ContentType);
});

app.MapGet("/captcha/validate", (string id, string code, ICaptcha captcha) =>
{
    var success = captcha.Validate(id, code);
    return Results.Ok(new { id, code, success });
});

app.Run();

Resource Management

• Fonts – Inject via IFontProvider. UseFileResources / UseFileFontOptions loads fonts from disk and exposes them through options.Image.FontFamily.
• Backgrounds – Provided by IBackgroundProvider. The default is a solid color, but you can register multiple background images and pick one via options.Image.BackgroundImage.
• Pipeline Steps – BackgroundStep, TextStep, NoiseStep, DistortionStep all implement ICaptchaPipelineStep. You can replace or extend them with custom steps.

Storage Options

• UseCaptchaMemoryStorage() – Uses IMemoryCache, ideal for single-node deployments or tests.
• UseCaptchaRedisStorage(options => { ... }) – Backs captcha storage with Redis; configure connection string, database index, key prefix, etc.

Feature Highlights

• Pure managed rendering pipeline powered by Vello + ImageSharp (PNG output by default).
• Fonts/backgrounds are provided by the host application; the library ships without embedded assets.
• DI-friendly configuration: .AddCaptcha().UseVelloRenderer().UseCaptchaMemoryStorage().
• Memory and Redis storage providers with async validation APIs.
• Minimal API sample with Swagger ready to debug.

Roadmap

• Additional captcha types: Chinese, arithmetic, slider, animated variants.
• Pluggable pipeline DSL similar to QrBuilder.
• GIF / WebP / ImageSharp encoders.
• Storage-level TTL strategies and hit stats for custom rate limiting.

Contributions and feature requests are always welcome!