DriveM.RateLimit.Core 1.0.0

RateLimit.Core

A reusable rate limiting library for .NET 8 microservices. This library provides flexible and configurable rate limiting functionality that can be easily integrated into any ASP.NET Core application.

Features

• Method-level rate limiting using attributes
• Global rate limiting for the entire application
• Multiple client identifier strategies (IP address, IP+Path, User ID, Custom header)
• Customizable headers for rate limit information
• Distributed cache support for scalable deployments
• Simple integration with dependency injection

Installation

dotnet add package RateLimit.Core

Quick Start

1. Register rate limiting services in your Program.cs file:

// Add rate limiting services
builder.Services.AddRateLimiting(options =>
{
    // Optional: Configure global rate limiting
    options.EnableGlobalRateLimiting = true;
    options.DefaultMaxRequests = 100;         // 100 requests
    options.DefaultTimeWindowInSeconds = 60;  // per minute
    
    // Optional: Configure client identification method for global rate limiting
    options.GlobalClientResolverStrategy = ClientResolverStrategy.IpAddress;
});

2. Add the middleware to your application pipeline:

// Add rate limiting middleware - place before endpoints/controllers
app.UseRateLimiting();

app.MapControllers();

3. Apply rate limiting to specific controller actions:

[HttpGet]
[RateLimit(MaxRequests = 5, TimeWindowInSeconds = 60)]  // 5 requests per minute
public IActionResult Get()
{
    return Ok("Rate limited endpoint");
}

Advanced Configuration

Client Identification Strategies

The library supports several strategies for identifying clients:

// IP Address only (default)
[RateLimit(MaxRequests = 10, TimeWindowInSeconds = 60, ClientResolverStrategy = ClientResolverStrategy.IpAddress)]

// IP Address + Request Path
[RateLimit(MaxRequests = 5, TimeWindowInSeconds = 30, ClientResolverStrategy = ClientResolverStrategy.IpAndPath)]

// User ID (from claims)
[RateLimit(MaxRequests = 20, TimeWindowInSeconds = 60, ClientResolverStrategy = ClientResolverStrategy.UserId)]

// Custom header
[RateLimit(MaxRequests = 100, TimeWindowInSeconds = 60, ClientResolverStrategy = ClientResolverStrategy.CustomHeader)]

When using CustomHeader, you can specify the header name in options:

services.AddRateLimiting(options =>
{
    options.ClientIdentifierHeader = "X-API-Key";
});

Custom Response Headers

services.AddRateLimiting(options =>
{
    options.IncludeRateLimitHeaders = true;
    options.RateLimitHeader = "X-RateLimit-Limit";
    options.RateLimitRemainingHeader = "X-RateLimit-Remaining";
});

Using with Distributed Cache

For scaling across multiple instances, use a distributed cache implementation:

// Add your preferred distributed cache implementation
builder.Services.AddStackExchangeRedisCache(options =>
{
    options.Configuration = "localhost:6379";
});

// Register rate limiting services
builder.Services.AddRateLimiting();

License

MIT