Redis with redis-rs (Rust)

Uses the redis crate 1.8. The code is an ordinary application for the original database; nothing in it knows about MachNoSQL.

The only change

redis://:secret@redis.example.com:6379/0
redis://:secret@machnosql.example.com:6379/0

The address comes from the environment variable REDIS_URL, so switching to MachNoSQL changes configuration only.

Run

export REDIS_URL='redis://:secret@machnosql.example.com:6379/0'
cargo run

Source

The program as it is kept and tested in the Mach Database NoSQL repository; highlighted lines read the connection setting.

src/main.rs

//! Cache, counter, session and leaderboard on Redis, unchanged on MachNoSQL.

use redis::{Commands, RedisResult};

fn main() -> RedisResult<()> {
    let url = std::env::var("REDIS_URL").expect("set REDIS_URL");
    let client = redis::Client::open(url)?;
    let mut con = client.get_connection()?;

    let _: () = con.set_ex("cache:home", "<html>...</html>", 60)?;
    let cached: String = con.get("cache:home")?;
    let ttl: i64 = con.ttl("cache:home")?;
    println!("cached: {cached} ttl: {ttl}");

    let views: i64 = con.incr("views:home", 1)?;
    println!("views: {views}");

    let _: () = con.hset_multiple("session:42", &[("user", "ada"), ("cart_items", "3")])?;
    let session: std::collections::HashMap<String, String> = con.hgetall("session:42")?;
    println!("session: {session:?}");

    let _: () = con.zadd_multiple("leaderboard", &[(120, "ada"), (95, "linus"), (130, "grace")])?;
    let top: Vec<(String, f64)> = con.zrevrange_withscores("leaderboard", 0, 2)?;
    println!("top: {top:?}");

    let (count,): (i64,) = redis::pipe()
        .atomic()
        .incr("orders:count", 1)
        .lpush("orders:recent", "order-1001")
        .ignore()
        .ltrim("orders:recent", 0, 99)
        .ignore()
        .query(&mut con)?;
    println!("pipeline: orders {count}");
    Ok(())
}

Cargo.toml

[package]
name = "machnosql-example-redis"
version = "0.1.0"
edition = "2024"
publish = false

[dependencies]
redis = "1.8.1"