working version

Crexi.Auctions.API/Controllers/AuctionsController.cs

@@ -0,0 +1,22 @@
+using Microsoft.AspNetCore.Mvc;
+
+namespace Crexi.Auctions.API.Controllers
+{
+    [ApiController]
+    [Route("[controller]")]
+    public class AuctionsController : ControllerBase
+    {
+        private readonly ILogger<AuctionsController> _logger;
+
+        public AuctionsController(ILogger<AuctionsController> logger)
+        {
+            _logger = logger;
+        }
+
+        [HttpGet]
+        public int Get()
+        {
+            return 1;
+        }
+    }
+}

Crexi.Auctions.API/Crexi.Auctions.API.csproj

@@ -0,0 +1,22 @@
+<Project Sdk="Microsoft.NET.Sdk.Web">
+
+  <PropertyGroup>
+    <TargetFramework>net6.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Swashbuckle.AspNetCore" Version="6.5.0" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\RateLimiter\Crexi.API.Common.RateLimiter.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.AspNetCore.Authentication.JwtBearer" Version="6.0.0" />
+    <PackageReference Include="System.IdentityModel.Tokens.Jwt" Version="8.2.1" />
+  </ItemGroup>
+
+</Project>

Crexi.Auctions.API/Middleware/RateLimiter/RateLimiterConfigurator.cs

@@ -0,0 +1,41 @@
+using Crexi.API.Common.RateLimiter.Interfaces;
+using Crexi.API.Common.RateLimiter.Rules;
+
+namespace Crexi.Auctions.API.Middleware.RateLimiter
+{
+    public static class RateLimiterConfigurator
+    {
+        public static void ConfigureRateLimitingRules(IRateLimiter rateLimiter)
+        {
+            var usRateLimitRule = new FixedWindowRateLimitRule(
+                maxRequestsPerClient: 10,
+                timeWindow: TimeSpan.FromSeconds(10)
+            );
+
+            var euRateLimitRule = new TimeSinceLastCallRule(
+                requiredInterval: TimeSpan.FromSeconds(2)
+            );
+
+            var usConditionalRule = new ConditionalRateLimitRule(
+                condition: client => client.Location == "US",
+                rule: usRateLimitRule
+            );
+
+            var euConditionalRule = new ConditionalRateLimitRule(
+                condition: client => client.Location == "EU",
+                rule: euRateLimitRule
+            );
+
+            var compositeRule = new CompositeRateLimitRule(new[]
+            {
+                usConditionalRule,
+                euConditionalRule
+            });
+
+            rateLimiter.ConfigureResource("/Auctions", compositeRule);
+
+            var anotherRule = new FixedWindowRateLimitRule(50, TimeSpan.FromMinutes(10));
+            rateLimiter.ConfigureResource("/AuctionSettings", anotherRule);
+        }
+    }
+}

Crexi.Auctions.API/Middleware/RateLimiter/RateLimiterMiddleware.cs

@@ -0,0 +1,42 @@
+using Crexi.API.Common.RateLimiter.Interfaces;
+
+public class RateLimiterMiddleware
+{
+    private readonly RequestDelegate _next;
+    private readonly IRateLimiter _rateLimiter;
+    private readonly ITokenToClientConverter _tokenToClientConverter;
+    private readonly ITokenExtractor _tokenExtractor;
+
+    public RateLimiterMiddleware(RequestDelegate next, IRateLimiter rateLimiter, ITokenToClientConverter tokenToClientConverter, ITokenExtractor tokenExtractor)
+    {
+        _next = next;
+        _rateLimiter = rateLimiter;
+        _tokenToClientConverter = tokenToClientConverter;
+        _tokenExtractor = tokenExtractor;
+    }
+
+    public async Task InvokeAsync(HttpContext context)
+    {
+        var accessToken = _tokenExtractor.ExtractToken(context);
+
+        var client = _tokenToClientConverter.ConvertTokenToClient(accessToken);
+
+        if (client == null)
+        {
+            context.Response.StatusCode = StatusCodes.Status401Unauthorized;
+            await context.Response.WriteAsync("Invalid or malformed access token.");
+            return;
+        }
+
+        var resource = context.Request.Path.Value;
+
+        if (!_rateLimiter.IsRequestAllowed(client, resource))
+        {
+            context.Response.StatusCode = StatusCodes.Status429TooManyRequests;
+            await context.Response.WriteAsync("Rate limit exceeded.");
+            return;
+        }
+
+        await _next(context);
+    }
+}

Crexi.Auctions.API/Middleware/RateLimiter/Util/ITokenExtractor.cs

@@ -0,0 +1,5 @@
+
+public interface ITokenExtractor
+{
+    string ExtractToken(HttpContext context);
+}

Crexi.Auctions.API/Middleware/RateLimiter/Util/ITokenToClientConverter.cs

@@ -0,0 +1,6 @@
+using Crexi.API.Common.RateLimiter.Models;
+
+public interface ITokenToClientConverter
+{
+    Client ConvertTokenToClient(string token);
+}

Crexi.Auctions.API/Middleware/RateLimiter/Util/TokenExtractor.cs

@@ -0,0 +1,13 @@
+public class TokenExtractor : ITokenExtractor
+{
+    public string ExtractToken(HttpContext context)
+    {
+        if (context.Request.Headers.TryGetValue("Authorization", out var authorizationHeader))
+        {
+            var token = authorizationHeader.ToString().Split(' ').Last();
+            return token;
+        }
+
+        return null;
+    }
+}

Crexi.Auctions.API/Middleware/RateLimiter/Util/TokenToClientConverter.cs

@@ -0,0 +1,30 @@
+using Crexi.API.Common.RateLimiter.Models;
+using System.IdentityModel.Tokens.Jwt;
+
+public class TokenToClientConverter : ITokenToClientConverter
+{
+    public Client ConvertTokenToClient(string token)
+    {
+        try
+        {
+            var handler = new JwtSecurityTokenHandler();
+            var jwtToken = handler.ReadJwtToken(token);
+
+            // Extract client ID and location from token claims
+            var clientId = jwtToken.Claims.FirstOrDefault(c => c.Type == "client_id")?.Value;
+            var clientLocation = jwtToken.Claims.FirstOrDefault(c => c.Type == "location")?.Value;
+
+            if (string.IsNullOrEmpty(clientId) || string.IsNullOrEmpty(clientLocation))
+            {
+                return null;
+            }
+
+            return new Client(clientId, clientLocation);
+        }
+        catch (Exception ex)
+        {
+            // TODO logging
+            return null;
+        }
+    }
+}

Crexi.Auctions.API/Program.cs

@@ -0,0 +1,67 @@
+using Crexi.API.Common.RateLimiter;
+using Crexi.API.Common.RateLimiter.Interfaces;
+using Crexi.Auctions.API.Middleware.RateLimiter;
+using Microsoft.OpenApi.Models;
+
+var builder = WebApplication.CreateBuilder(args);
+
+// Register services
+builder.Services.AddControllers();
+builder.Services.AddEndpointsApiExplorer();
+builder.Services.AddSwaggerGen(c =>
+{
+    c.SwaggerDoc("v1", new OpenApiInfo { Title = "Crexi Auction API", Version = "v1" });
+
+    // Add the security definition for Bearer tokens
+    c.AddSecurityDefinition("Bearer", new OpenApiSecurityScheme
+    {
+        Description = "JWT Authorization header using the Bearer scheme. Example: \"Bearer {token}\"",
+        Name = "Authorization",
+        In = ParameterLocation.Header,
+        Type = SecuritySchemeType.ApiKey,
+        Scheme = "Bearer"
+    });
+
+    // Add the security requirement to include the Bearer token globally
+    c.AddSecurityRequirement(new OpenApiSecurityRequirement()
+    {
+        {
+            new OpenApiSecurityScheme
+            {
+                Reference = new OpenApiReference
+                {
+                    Type = ReferenceType.SecurityScheme,
+                    Id = "Bearer"
+                },
+                Scheme = "oauth2",
+                Name = "Bearer",
+                In = ParameterLocation.Header,
+            },
+            new List<string>()
+        }
+    });
+});
+
+builder.Services.AddSingleton<IRateLimiter, RateLimiter>();
+builder.Services.AddTransient<ITokenToClientConverter, TokenToClientConverter>();
+builder.Services.AddTransient<ITokenExtractor, TokenExtractor>();
+
+var app = builder.Build();
+
+if (app.Environment.IsDevelopment())
+{
+    app.UseSwagger();
+    app.UseSwaggerUI();
+}
+
+app.UseHttpsRedirection();
+
+app.UseAuthentication();
+app.UseAuthorization();
+
+RateLimiterConfigurator.ConfigureRateLimitingRules(app.Services.GetRequiredService<IRateLimiter>());
+app.UseMiddleware<RateLimiterMiddleware>();
+
+app.MapControllers();
+
+app.Run();

Crexi.Auctions.API/Properties/launchSettings.json

@@ -0,0 +1,31 @@
+{
+  "$schema": "https://json.schemastore.org/launchsettings.json",
+  "iisSettings": {
+    "windowsAuthentication": false,
+    "anonymousAuthentication": true,
+    "iisExpress": {
+      "applicationUrl": "http://localhost:42884",
+      "sslPort": 44366
+    }
+  },
+  "profiles": {
+    "Crexi.Auctions.API": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "launchUrl": "swagger",
+      "applicationUrl": "https://localhost:7145;http://localhost:5071",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+    "IIS Express": {
+      "commandName": "IISExpress",
+      "launchBrowser": true,
+      "launchUrl": "swagger",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    }
+  }
+}

Crexi.Auctions.API/appsettings.Development.json

@@ -0,0 +1,8 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  }
+}

Crexi.Auctions.API/appsettings.json

@@ -0,0 +1,9 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  },
+  "AllowedHosts": "*"
+}

RateLimiter.Tests/RateLimiter.Tests.csproj → RateLimiter.Tests/Crexi.API.Common.RateLimiter.Tests.csproj

@@ -5,7 +5,7 @@
     <Nullable>enable</Nullable>
   </PropertyGroup>
   <ItemGroup>
-    <ProjectReference Include="..\RateLimiter\RateLimiter.csproj" />
+    <ProjectReference Include="..\RateLimiter\Crexi.API.Common.RateLimiter.csproj" />
   </ItemGroup>
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.5.0" />