How to build a REST API with Axum

Use the axum crate with tokio to define routes and run an async server. Add dependencies to Cargo.toml, define a handler function, and start the server with axum::serve.

use axum::{routing::get, Router};

#[tokio::main]
async fn main() {
    let app = Router::new().route("/", get(handler));
    let listener = tokio::net::TcpListener::bind("0.0.0.0:3000").await.unwrap();
    axum::serve(listener, app).await.unwrap();
}

async fn handler() -> &'static str {
    "Hello, World!"
}

In Cargo.toml, add:

[dependencies]
axum = "0.7"
tokio = { version = "1", features = ["full"] }

Axum is a web framework for Rust that lets you build fast, safe web servers using async code. You define routes that map URLs to functions, and the framework handles the rest. Think of it like setting up a menu where each dish (URL) is prepared by a specific chef (function).