Rust MiniRedis

A lightweight, blazingly-fast in-memory key-value store inspired by Redis, built with Rust and Tokio.

Features

• In-memory key-value storage
• Automatic key expiration (TTL)
• Support for string, list (comma-separated), and hash (key:value pairs) values
• Async TCP server via Tokio
• Commands: SET, GET, UPDATE, DEL, EXISTS, RENAME, TYPE, CLEARALL, PING

Installation

Install directly from crates.io:

cargo install rs-miniredis

Running the Server

rs-miniredis

The server starts on 127.0.0.1:6379 by default.

To specify a custom host and port:

rs-miniredis --host 0.0.0.0 --port 6379

Requirements

• Rust

Contributing

Clone the repository

git clone https://github.com/Aliemeka/rs-miniredis.git

Running the Server after cloning

cargo run

You can also pass host and port flags:

cargo run -- --host 0.0.0.0 --port 6379

The server starts on 127.0.0.1:6379 by default.

Querying the Server with NetCat

Mac

nc 127.0.0.1 6379

Linux

nc -q 0 127.0.0.1 6379

Once connected, type commands directly:

SET name Alice
GET name
UPDATE name Bob
EXISTS name
TYPE name
RENAME name username
DEL username
CLEARALL
PING

One-liner commands (Mac & Linux)

# SET a key
echo "SET name Alice" | nc 127.0.0.1 6379

# SET a key with a custom TTL (in seconds)
echo "SET name Alice 120" | nc 127.0.0.1 6379

# GET a key
echo "GET name" | nc 127.0.0.1 6379

# SET a list value (comma-separated)
echo "SET colors red,green,blue" | nc 127.0.0.1 6379

# SET a hash value (comma-separated key:value pairs)
echo "SET user name:Alice,age:30,city:Lagos" | nc 127.0.0.1 6379

# UPDATE a key's value (can change type)
echo "UPDATE name Bob" | nc 127.0.0.1 6379

# UPDATE a string to a list
echo "UPDATE name red,green,blue" | nc 127.0.0.1 6379

# UPDATE a key with a new TTL
echo "UPDATE name Alice 300" | nc 127.0.0.1 6379

# Check if a key exists
echo "EXISTS name" | nc 127.0.0.1 6379

# Get the type of a stored value
echo "TYPE name" | nc 127.0.0.1 6379

# Rename a key
echo "RENAME name username" | nc 127.0.0.1 6379

# Clear all keys
echo "CLEARALL" | nc 127.0.0.1 6379

# Ping the server
echo "PING" | nc 127.0.0.1 6379

# DELETE a key
echo "DEL name" | nc 127.0.0.1 6379

Commands

Command	Syntax	Description
SET	SET <key> <value> [ttl]	Store a value. Optional TTL in seconds (default: 60).
GET	GET <key>	Retrieve a value by key. Returns Nil if not found or expired.
UPDATE	UPDATE <key> <value> [ttl]	Update an existing key. The new value can be a different type entirely.
DEL or DELETE	DEL <key> or DELETE <key>	Delete a key.
EXISTS	EXISTS <key>	Returns YES if the key exists and has not expired, otherwise NO.
RENAME	RENAME <old_key> <new_key>	Rename a key. Returns an error if the key does not exist.
TYPE	TYPE <key>	Returns the value type: String, VecStr, or Hash.
CLEARALL	CLEARALL	Delete all keys from the store.
PING	PING	Health check. Returns PONG.

List Values

Pass a comma-separated string as the value to store a list:

SET fruits apple,banana,mango
GET fruits
# => apple,banana,mango, type: VecStr

Hash Values

Pass comma-separated key:value pairs to store a hash map:

SET user name:Alice,age:30,city:Lagos
GET user
# => name:Alice,age:30,city:Lagos, type: Hash

If any pair contains a :, the entire value is treated as a hash. Otherwise it falls back to a list.

Updating Values

UPDATE works like SET but only succeeds if the key already exists. Crucially, the new value can be a completely different type from the old one:

SET score 42
# score is a String

UPDATE score math:90,english:85,science:78
# score is now a Hash

UPDATE score 90,85,78
# score is now a VecStr

Add to your project

cargo add rs-miniredis

Project Structure

src/
├── main.rs      # Entry point
├── runner.rs    # TCP server, client handler, command parsing
└── state.rs     # In-memory store with TTL logic

Dependencies

• tokio — Async runtime
• clap — CLI