Add Token Bucket and GCRA rate limiting algorithms (#152)

* added token bucket rate limiter

* added GCRA rate limiter; integrated new rate limiting algos with volga

* updated token bucket rate limiter to use microseconds for last_seen and eviction grace.

Author: RomanEmreis

README.md

@@ -5,7 +5,7 @@ Fast, simple, and high-performance web framework for Rust, built on top of
 Volga is designed to make building HTTP services straightforward and explicit,
 while keeping performance predictable and overhead minimal.
 
-[![latest](https://img.shields.io/badge/latest-0.8.1-blue)](https://crates.io/crates/volga)
+[![latest](https://img.shields.io/badge/latest-0.8.2-blue)](https://crates.io/crates/volga)
 [![latest](https://img.shields.io/badge/rustc-1.90+-964B00)](https://crates.io/crates/volga)
 [![License: MIT](https://img.shields.io/badge/License-MIT-violet.svg)](https://github.com/RomanEmreis/volga/blob/main/LICENSE)
 [![Build](https://github.com/RomanEmreis/volga/actions/workflows/rust.yml/badge.svg)](https://github.com/RomanEmreis/volga/actions/workflows/rust.yml)
@@ -46,7 +46,7 @@ Volga is a good fit if you:
 ### Dependencies
 ```toml
 [dependencies]
-volga = "0.8.1"
+volga = "0.8.2"
 tokio = { version = "1", features = ["full"] }
 ```
 ### Simple request handler

examples/rate_limiting/src/main.rs

@@ -8,7 +8,7 @@ use std::time::Duration;
 use serde::Deserialize;
 use volga::{
     auth::{Claims, roles, DecodingKey}, 
-    rate_limiting::{FixedWindow, SlidingWindow, by},
+    rate_limiting::{FixedWindow, SlidingWindow, TokenBucket, Gcra, by},
     App
 };
 
@@ -26,20 +26,25 @@ fn main() {
         .with_sliding_window(
             SlidingWindow::new(100, Duration::from_secs(15))
         )
-        .with_sliding_window(
-            SlidingWindow::new(100, Duration::from_secs(30))
+        .with_token_bucket(
+            TokenBucket::new(100, 1.0)
+        )
+        .with_gcra(
+            Gcra::new(50.0, 10)
                 .with_name("burst")
         );
 
-    app.use_fixed_window(by::ip());
+    app.use_token_bucket(by::ip());
 
     app.group("/api", |api| {
-        api.sliding_window(by::header("x-api-key"));
+        api.fixed_window(by::header("x-api-key"));
 
         api.map_get("/fixed", async || "Hello from fixed window!");
         api.map_get("/sliding", async || "Hello from sliding window!")
+            .sliding_window(by::header("x-api-key"));
+        api.map_get("/gcra", async || "Hello from GCRA!")
             .authorize::<Claims>(roles(["admin", "user"]))
-            .sliding_window(by::user(|c: &Claims| c.sub.as_str()).using("burst")); 
+            .gcra(by::user(|c: &Claims| c.sub.as_str()).using("burst")); 
     });
 
     app.run_blocking();

volga-dev-cert/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "volga-dev-cert"
-version = "0.8.1"
+version = "0.8.2"
 readme = "README.md"
 description = "A Rust library for generating self-signed TLS certificates for local development."
 edition.workspace = true

volga-dev-cert/README.md

@@ -1,7 +1,7 @@
 # Volga Development Certificates
 A Rust library for generating self-signed TLS certificates for local development.
 
-[![latest](https://img.shields.io/badge/latest-0.8.1-blue)](https://crates.io/crates/volga)
+[![latest](https://img.shields.io/badge/latest-0.8.2-blue)](https://crates.io/crates/volga)
 [![latest](https://img.shields.io/badge/rustc-1.90+-964B00)](https://crates.io/crates/volga)
 [![License: MIT](https://img.shields.io/badge/License-MIT-violet.svg)](https://github.com/RomanEmreis/volga/blob/main/LICENSE)
 [![Build](https://github.com/RomanEmreis/volga/actions/workflows/rust.yml/badge.svg)](https://github.com/RomanEmreis/volga/actions/workflows/rust.yml)

volga-di/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "volga-di"
-version = "0.8.1"
+version = "0.8.2"
 readme = "README.md"
 description = "Dependency Injection tools for Volga Web Framework"
 edition.workspace = true

volga-di/README.md

@@ -1,7 +1,7 @@
 # Volga DI
 A standalone, flexible, and easy-to-configure DI container.
 
-[![latest](https://img.shields.io/badge/latest-0.8.1-blue)](https://crates.io/crates/volga)
+[![latest](https://img.shields.io/badge/latest-0.8.2-blue)](https://crates.io/crates/volga)
 [![latest](https://img.shields.io/badge/rustc-1.90+-964B00)](https://crates.io/crates/volga)
 [![License: MIT](https://img.shields.io/badge/License-MIT-violet.svg)](https://github.com/RomanEmreis/volga/blob/main/LICENSE)
 [![Build](https://github.com/RomanEmreis/volga/actions/workflows/rust.yml/badge.svg)](https://github.com/RomanEmreis/volga/actions/workflows/rust.yml)
@@ -15,12 +15,12 @@ A standalone, flexible, and easy-to-configure DI container.
 #### Standalone
 ```toml
 [dependencies]
-volga-di = "0.8.1"
+volga-di = "0.8.2"
 ```
 #### Part of Volga Web Framework
 ```toml
 [dependencies]
-volga = { version = "0.8.1", features = ["di"] }
+volga = { version = "0.8.2", features = ["di"] }
 ```
 
 ### Example

volga-macros/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "volga-macros"
-version = "0.8.1"
+version = "0.8.2"
 readme = "README.md"
 description = "Macros for Volga Web Framework"
 edition.workspace = true

volga-macros/README.md

@@ -1,7 +1,7 @@
 # Volga Macros
 Macros library for Volga Web Framework
 
-[![latest](https://img.shields.io/badge/latest-0.8.1-blue)](https://crates.io/crates/volga)
+[![latest](https://img.shields.io/badge/latest-0.8.2-blue)](https://crates.io/crates/volga)
 [![latest](https://img.shields.io/badge/rustc-1.90+-964B00)](https://crates.io/crates/volga)
 [![License: MIT](https://img.shields.io/badge/License-MIT-violet.svg)](https://github.com/RomanEmreis/volga/blob/main/LICENSE)
 [![Build](https://github.com/RomanEmreis/volga/actions/workflows/rust.yml/badge.svg)](https://github.com/RomanEmreis/volga/actions/workflows/rust.yml)
@@ -13,6 +13,6 @@ Macros library for Volga Web Framework
 ## Dependencies
 ```toml
 [dependencies]
-volga = { version = "0.8.1", features = ["macros"] }
+volga = { version = "0.8.2", features = ["macros"] }
 ```
 

volga-rate-limiter/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "volga-rate-limiter"
-version = "0.8.1"
+version = "0.8.2"
 readme = "README.md"
 description = "Macros for Volga Web Framework"
 edition.workspace = true

volga-rate-limiter/README.md

@@ -5,7 +5,7 @@ A lightweight and efficient rate-limiting library for Rust.
 This crate provides in-memory rate limiting algorithms designed
 for high-performance HTTP services and middleware.
 
-[![latest](https://img.shields.io/badge/latest-0.8.1-blue)](https://crates.io/crates/volga)
+[![latest](https://img.shields.io/badge/latest-0.8.2-blue)](https://crates.io/crates/volga)
 [![latest](https://img.shields.io/badge/rustc-1.90+-964B00)](https://crates.io/crates/volga)
 [![License: MIT](https://img.shields.io/badge/License-MIT-violet.svg)](https://github.com/RomanEmreis/volga/blob/main/LICENSE)
 [![Build](https://github.com/RomanEmreis/volga/actions/workflows/rust.yml/badge.svg)](https://github.com/RomanEmreis/volga/actions/workflows/rust.yml)
@@ -33,15 +33,26 @@ synchronize state across multiple processes or machines.
 
 The following rate-limiting algorithms are provided:
 
-- [`FixedWindowRateLimiter`]
+- `FixedWindowRateLimiter`
   - Counts requests in discrete, fixed-size time windows
   - Very fast and simple
   - May allow short bursts at window boundaries
 
-- [`SlidingWindowRateLimiter`]
+- `SlidingWindowRateLimiter`
   - Uses a sliding time window with linear weighting
   - Provides smoother request distribution
   - Slightly more expensive than a fixed window
+  
+- `TokenBucketRateLimiter`
+  - Allows bursts up to a token bucket capacity
+  - Enforces a steady average refill rate
+  - Simple and flexible for bursty traffic
+
+- `GcraRateLimiter`
+  - Uses the Generic Cell Rate Algorithm (GCRA)
+  - Smooths traffic with explicit burst tolerance
+  - Accurate average rate enforcement
+
 
 ## Time Source Abstraction
 
@@ -52,7 +63,7 @@ This allows:
 - Custom time implementations if needed
 
 The default implementation, [`SystemTimeSource`], is based on
-`std::time::SystemTime`.
+`std::time::Instant`.
 
 ## Concurrency Model