Rustis

A Redis clone built from scratch in Rust. This project implements core Redis functionality including data structures, persistence, replication, pub/sub messaging, and more.

Features

Data Structures

Strings

• SET key value [PX milliseconds] - Set a key with optional expiration
• GET key - Get the value of a key
• INCR key - Increment the integer value of a key

Lists

• LPUSH key value [value ...] - Prepend values to a list
• RPUSH key value [value ...] - Append values to a list
• LPOP key [count] - Remove and return elements from the head
• LRANGE key start stop - Get a range of elements
• LLEN key - Get the length of a list

Sorted Sets

• ZADD key score member - Add a member with score to a sorted set
• ZRANGE key start stop - Get members by index range
• ZRANK key member - Get the rank of a member
• ZSCORE key member - Get the score of a member
• ZCARD key - Get the number of members
• ZREM key member - Remove a member

Streams

• XADD key id field value [field value ...] - Append an entry to a stream
• XRANGE key start end - Get a range of entries
• XREAD STREAMS key id - Read entries from streams

Pub/Sub Messaging

• SUBSCRIBE channel [channel ...] - Subscribe to channels
• UNSUBSCRIBE channel [channel ...] - Unsubscribe from channels
• PUBLISH channel message - Publish a message to a channel

Geospatial

• GEOADD key longitude latitude member - Add geospatial items
• GEOPOS key member [member ...] - Get positions of members
• GEODIST key member1 member2 [unit] - Get distance between members
• GEOSEARCH key FROMMEMBER member BYRADIUS radius unit - Search for members within radius

Transactions

• MULTI - Start a transaction
• EXEC - Execute queued commands
• DISCARD - Discard queued commands

Persistence

• RDB Loading - Automatically loads data from RDB files on startup
• CONFIG GET dir - Get the database directory
• CONFIG GET dbfilename - Get the RDB filename
• KEYS * - Get all keys in the database

Replication

• Master/Slave replication support
• INFO replication - Get replication information
• REPLCONF - Replication configuration
• PSYNC - Partial synchronization

Authentication

• AUTH password - Authenticate to the server
• ACL - Access control list management

General Commands

• PING - Test connection
• ECHO message - Echo a message
• TYPE key - Get the type of a key

Getting Started

Prerequisites

• Rust (latest stable version)
• Cargo

Building

cargo build --release

Running

Basic server:

cargo run

With custom port:

cargo run -- --port 6380

With RDB persistence:

cargo run -- --dir /path/to/data --dbfilename dump.rdb

As a replica:

cargo run -- --port 6380 --replicaof "127.0.0.1 6379"

Connecting

Use redis-cli or any Redis client:

redis-cli -p 6379

Architecture

src/
├── main.rs              # Server entry point and connection handling
├── resp/                # RESP protocol implementation
│   ├── parser.rs        # RESP message parser
│   ├── serializer.rs    # RESP message serializer
│   └── types.rs         # RESP data types
├── db/                  # Database core
│   └── core.rs          # In-memory data store with expiration
├── commands/            # Command implementations
│   ├── dispatcher.rs    # Command routing
│   ├── string_cmds.rs   # String commands
│   ├── list_cmds.rs     # List commands
│   ├── sets_cmd.rs      # Sorted set commands
│   ├── streams_cmds.rs  # Stream commands
│   ├── pubsub_cmds.rs   # Pub/Sub commands
│   ├── geospatial_cmds.rs # Geospatial commands
│   ├── persistence_cmds.rs # Persistence commands
│   ├── repl_cmds.rs     # Replication commands
│   └── auth_cmds.rs     # Authentication commands
├── rdb/                 # RDB persistence
│   └── parser.rs        # RDB file parser
├── replication/         # Replication support
│   └── handshake.rs     # Master-slave handshake
└── client.rs            # Client state management

Technical Highlights

• Async I/O - Built with Tokio for high-performance async networking
• RESP Protocol - Full implementation of Redis Serialization Protocol
• Memory Efficient - Uses bytes::Bytes for zero-copy operations
• Concurrent Access - Thread-safe data structures with Arc<Mutex<>>
• Background Tasks - Automatic key expiration via background task
• RDB Compatibility - Reads standard Redis RDB files (version 11)

Command Line Options

Option	Description	Default
--port <port>	Server port	6379
--dir <path>	Directory for RDB files	None
--dbfilename <name>	RDB filename	None
--replicaof "<host> <port>"	Run as replica of master	None

Acknowledgments

• Inspired by Redis