RaftKV - Asynchronous Distributed Key-Value Store

RaftKV is a distributed Key-Value store built in Rust, implementing the Raft Consensus Algorithm. It handles leader election, log replication, and consistent data storage across a cluster of nodes.

This project demonstrates Intermediate-to-Advanced Rust patterns, focusing on asynchronous concurrency, type safety, and modular architecture.

🚀 Key Technical Highlights

• Asynchronous Core: Built on the Tokio runtime. The consensus engine uses non-blocking I/O for high-performance networking and timer management, avoiding costly thread spawning.
• Pluggable Architecture:
  • Storage Abstraction: Uses #[async_trait] to decouple the Raft logic from the underlying storage engine. This allows hot-swapping between MemStorage (for testing) and persistent FileStorage.
  • Network Abstraction: Decoupled network layer allowing for easy mocking and different transport implementations (gRPC, TCP, Channels).
• Type-Safe Design: Leveraging Rust's strong type system (Enums & Pattern Matching) to enforce valid state transitions and prevent "stringly typed" errors in command parsing.
• Workspace Structure: organized as a Cargo Workspace with isolated crates (raft-core, kv-store, api) to enforce separation of concerns.

🏗️ Architecture

The project is split into three main crates:

• crates/raft-core: The pure consensus logic. It defines the RaftNode, RaftStorage trait, and RPC types. It is completely agnostic of the web layer.
• crates/kv-store: A persistent Log Structured Merge (LSM)-lite storage engine. It provides durability by appending to a write-ahead log (WAL).
• crates/api: The HTTP Edge layer using Actix-Web. It translates REST requests into Raft commands.

🛠️ Usage

Prerequisites

• Rust (1.70+)

Running a Node

# Start the server (defaults to port 8080)
cargo run --bin raft-server

API Examples

Set a Value (Proposes to Raft Leader)

curl -X POST http://localhost:8080/set -d '{"key": "foo", "value": "bar"}' -H "Content-Type: application/json"

Get a Value (Strongly Consistent Read)

curl http://localhost:8080/get/foo

🧪 Testing

The project includes an InMemory Storage adapter (MemStorage) designed for high-speed integration testing of the consensus logic without hitting the disk.

cargo test