Importing Router objects from other directories in Axum

Nov 11, 2023 • 1 min read

Whenever I work on backend code, I prefer to use a Django-styled approach to my directory structure. This means I’ll have several apps that have isolated logic.

So, when I started using Axum, a Rust-based web framework, I adopted a similar structure. In order to achieve this structure, we have to make sure that each app will export a single Router object.

We would then nest the exported Router object with our base Router.

Here’s an example of this. Suppose that we have the following code that lives within src/example/router.rs.

use axum::{routing::get, Json, Router};
use serde::Serialize;

pub fn get_example_router() -> Router {
    Router::new().route("/", get(get_hello))
}

async fn get_hello() -> Json<HelloWorld> {
    Json(HelloWorld {
        message: String::from("Hello, world"),
    })
}

#[derive(Serialize)]
struct HelloWorld {
    message: String,
}

In this file, we’re creating a local Router object that has our handler for our get_hello endpoint. This local Router will then be nested on our base Router object which I’ll show shortly.

Now in our src/main.rs file, we’re going to have the following:

mod example;

use axum::Router;

use example::routes::get_example_router;

#[tokio::main]
async fn main() {
    let app = Router::new().nest("/api/example", get_example_router());

    axum::Server::bind(&"0.0.0.0:3000".parse().unwrap())
        .serve(app.into_make_service())
        .await
        .unwrap();
}