Rust: Create a basic web/HTTP server

For the web server we’re going to use the same HTTP library we used for making requests, Hyper. The Hyper docs actually have a really great guide for creating a server which is exactly what this has been based off. Here’s my version:

use hyper::{Body, Request, Response, Server, Method, StatusCode};
use hyper::service::{make_service_fn, service_fn};

async fn echo(req: Request<Body>) -> Result<Response<Body>, hyper::Error> {
    match (req.method(), req.uri().path()) {
        // Serve some instructions at /
        (&Method::GET, "/") => Ok(Response::new(Body::from(
            "Welcome! Try a GET to /hello",
        ))),

        (&Method::GET, "/hello") => Ok(Response::new(Body::from(
            "World!",
        ))),

        // Simply echo the body back to the client.
        (&Method::POST, "/echo") => Ok(Response::new(req.into_body())),

        // Return the 404 Not Found for other routes.
        _ => {
            let mut not_found = Response::default();
            *not_found.status_mut() = StatusCode::NOT_FOUND;
            Ok(not_found)
        }
    }
}

async fn shutdown_signal() {
    // Wait for the CTRL+C signal
    tokio::signal::ctrl_c()
        .await
        .expect("failed to install CTRL+C signal handler");
}

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
    let addr = ([127, 0, 0, 1], 3000).into();

    let service = make_service_fn(|_| async { Ok::<_, hyper::Error>(service_fn(echo)) });

    let server = Server::bind(&addr).serve(service);

    println!("Listening on http://{}", addr);

    let graceful = server.with_graceful_shutdown(shutdown_signal());

    // Run this server for... forever!
    if let Err(e) = graceful.await {
        eprintln!("server error: {}", e);
    }

    Ok(())
}

Published: 25/03/2022

Hi, I'm Glenn! 👋

I've spent most of my career working with or at startups. You'll usually find me working in Product leadership roles, on an advisory board, or maybe as an early investor.

I've been the VP of Product & GTM @ Ockam. I led the Terraform product team @ HashiCorp, where we launched Terraform 1.0, Terraform Cloud, and a whole host of amazing capabilities that set the stage for a successful IPO. Prior to that I was part of the Startup Team @ AWS, and earlier still an early employee @ Heroku. I've also invested in a couple of dozen early stage startups.