khttp 0.1.2

A low-level synchronous HTTP/1.1 server/client library
Documentation

khttp (Karl's HTTP)

khttp is a low-level, synchronous HTTP/1.1 micro-framework for Rust - written from scratch with a focus on:

  • Keeping things simple
  • Low memory footprint
  • Low overhead / high performance
  • Minimal dependencies (libc, memchr)

Features:

  • HTTP/1.1 server & optional client (--features client)
  • Zero-copy(-ish) parsing with SIMD
  • Router with params & wildcards: /user/:id, /static/**
  • Automatic framing: Content-Length & Transfer-Encoding: chunked
  • Automatic date header
  • Custom epoll event loop on Linux (--features epoll)

Sample usage (from: examples/basics.rs)

use khttp::{Headers, Method::*, PreRoutingAction, Server, Status};
fn main() {
    let mut app = Server::builder("127.0.0.1:8080").unwrap();

    // handler type: dyn Fn(RequestContext, &mut ResponseHandle) -> io::Result<()>
    app.route(Get, "/", |ctx, res| {
        // Access the request via RequestContext
        println!(
            "Received request.\nmethod: {}\nquery: {}\nheaders:\n{}",
            ctx.method,
            ctx.uri.query().unwrap_or(""),
            ctx.headers
        );

        let mut headers = Headers::new();
        // Header names/values are Cow str and [u8] respectively,
        // so they support both owned values and references
        headers.add("key", b"value");
        headers.add(String::from("owned"), b"value".to_vec());

        // Send the response via ResponseHandle.
        // Response body is of type `impl Read` (here: response is sent as &[u8]).
        res.ok(&headers, &b"Hello, World!"[..])
    });

    app.route(Post, "/uppercase", |mut ctx, res| {
        // ctx.body() implements Read
        let body = ctx.body().string().unwrap_or_default();
        let response_body = body.to_ascii_uppercase();
        // "date" and "content-length" are automatically added
        res.ok(Headers::empty(), response_body.as_bytes())
    });

    // Routing supports named parameters
    app.route(Get, "/user/:id", |c, r| {
        let user_id: u64 = match c.params.get("id").unwrap().parse() {
            Ok(id) => id,
            Err(_) => {
                return r.send(&Status::BAD_REQUEST, Headers::empty(), &b"bad id"[..]);
            }
        };
        r.ok(Headers::empty(), format!("{}", user_id).as_bytes())
    });

    // All other requests are handled via the fallback_route
    app.fallback_route(|_, r| r.send(&Status::NOT_FOUND, Headers::empty(), &b"404"[..]));

    // Fine-tuning
    app.thread_count(20);
    app.max_request_head_size(16 * 1024);
    // Pre-routing-hooks runs after request-head is parsed, right before routing
    app.pre_routing_hook(|req, res, conn| {
        if conn.index() > 100 {
            let _ = res.send(&Status::of(429), Headers::close(), std::io::empty());
            return PreRoutingAction::Drop;
        }
        if req.http_version == 0 {
            let _ = res.send(&Status::of(505), Headers::close(), std::io::empty());
            return PreRoutingAction::Drop;
        }
        if matches!(req.method, Custom(_)) {
            let _ = res.send(&Status::of(405), Headers::close(), std::io::empty());
            return PreRoutingAction::Drop;
        }
        PreRoutingAction::Proceed
    });

    app.build().serve_epoll().unwrap();
}

See other examples for:

License

MIT.