Karl-Han · November 3, 2019 03:55
diff --git a/main.rs b/main.rs
 #![cfg(feature="unstable")]
 extern crate futures;
 extern crate hyper;

 use {
    hyper::{
        // Miscellaneous types from Hyper for working with HTTP.
        Body, Client, Request, Response, Server, Uri,

        // This function turns a closure which returns a future into an
        // implementation of the the Hyper `Service` trait, which is an
        // asynchronous function from a generic `Request` to a `Response`.
        service::service_fn,

        // A function which runs a future to completion using the Hyper runtime.
        rt::run,
    },
    futures::{
        // Extension trait for futures 0.1 futures, adding the `.compat()` method
        // which allows us to use `.await` on 0.1 futures.
        compat::Future01CompatExt,
        // Extension traits providing additional methods on futures.
        // `FutureExt` adds methods that work for all futures, whereas
        // `TryFutureExt` adds methods to futures that return `Result` types.
        future::{FutureExt, TryFutureExt},
    },
    std::net::SocketAddr,
 };

 async fn serve_req(_req: Request<Body>) -> Result<Response<Body>, hyper::Error> {
    // Always return successfully with a response containing a body with
    // a friendly greeting ;)
    Ok(Response::new(Body::from("hello, world!")))
 }

 async fn run_server(addr: SocketAddr) {
    println!("Listening on http://{}", addr);

    // Create a server bound on the provided address
    let serve_future = Server::bind(&addr)
        // Serve requests using our `async serve_req` function.
        // `serve` takes a closure which returns a type implementing the
        // `Service` trait. `service_fn` returns a value implementing the
        // `Service` trait, and accepts a closure which goes from request
        // to a future of the response. To use our `serve_req` function with
        // Hyper, we have to box it and put it in a compatability
        // wrapper to go from a futures 0.3 future (the kind returned by
        // `async fn`) to a futures 0.1 future (the kind used by Hyper).
        .serve(|| service_fn(|req| serve_req(req).boxed().compat()));

    // Wait for the server to complete serving or exit with an error.
    // If an error occurred, print it to stderr.
    if let Err(e) = serve_future.compat().await {
        eprintln!("server error: {}", e);
    }
 }

 fn main() {
    // Set the address to run our socket on.
    let addr = SocketAddr::from(([127, 0, 0, 1], 3000));

    // Call our `run_server` function, which returns a future.
    // As with every `async fn`, for `run_server` to do anything,
    // the returned future needs to be run. Additionally,
    // we need to convert the returned future from a futures 0.3 future into a
    // futures 0.1 future.
    let futures_03_future = run_server(addr);
    let futures_01_future = futures_03_future.unit_error().boxed().compat();

    // Finally, we can run the future to completion using the `run` function
    // provided by Hyper.
    run(futures_01_future);
 }
	#![cfg(feature="unstable")]
	extern crate futures;
	extern crate hyper;

	use {
	hyper::{
	// Miscellaneous types from Hyper for working with HTTP.
	Body, Client, Request, Response, Server, Uri,

	// This function turns a closure which returns a future into an
	// implementation of the the Hyper `Service` trait, which is an
	// asynchronous function from a generic `Request` to a `Response`.
	service::service_fn,

	// A function which runs a future to completion using the Hyper runtime.
	rt::run,
	},
	futures::{
	// Extension trait for futures 0.1 futures, adding the `.compat()` method
	// which allows us to use `.await` on 0.1 futures.
	compat::Future01CompatExt,
	// Extension traits providing additional methods on futures.
	// `FutureExt` adds methods that work for all futures, whereas
	// `TryFutureExt` adds methods to futures that return `Result` types.
	future::{FutureExt, TryFutureExt},
	},
	std::net::SocketAddr,
	};

	async fn serve_req(_req: Request<Body>) -> Result<Response<Body>, hyper::Error> {
	// Always return successfully with a response containing a body with
	// a friendly greeting ;)
	Ok(Response::new(Body::from("hello, world!")))
	}

	async fn run_server(addr: SocketAddr) {
	println!("Listening on http://{}", addr);

	// Create a server bound on the provided address
	let serve_future = Server::bind(&addr)
	// Serve requests using our `async serve_req` function.
	// `serve` takes a closure which returns a type implementing the
	// `Service` trait. `service_fn` returns a value implementing the
	// `Service` trait, and accepts a closure which goes from request
	// to a future of the response. To use our `serve_req` function with
	// Hyper, we have to box it and put it in a compatability
	// wrapper to go from a futures 0.3 future (the kind returned by
	// `async fn`) to a futures 0.1 future (the kind used by Hyper).
	.serve(\|\| service_fn(\|req\| serve_req(req).boxed().compat()));

	// Wait for the server to complete serving or exit with an error.
	// If an error occurred, print it to stderr.
	if let Err(e) = serve_future.compat().await {
	eprintln!("server error: {}", e);
	}
	}

	fn main() {
	// Set the address to run our socket on.
	let addr = SocketAddr::from(([127, 0, 0, 1], 3000));

	// Call our `run_server` function, which returns a future.
	// As with every `async fn`, for `run_server` to do anything,
	// the returned future needs to be run. Additionally,
	// we need to convert the returned future from a futures 0.3 future into a
	// futures 0.1 future.
	let futures_03_future = run_server(addr);
	let futures_01_future = futures_03_future.unit_error().boxed().compat();

	// Finally, we can run the future to completion using the `run` function
	// provided by Hyper.
	run(futures_01_future);
	}