hype

hype is a programmable L4/7 load balancer built into a composable web framework. It lets you build sophisticated reverse proxies, ingresses, or web application firewalls that can be dynamically programmed with a third-party controller.

Features

Fully async native HTTP/1.1 client and server implementations.
Easy-to-use service and routing APIs to create HTTP handlers and middleware.
Support for both store-and-forward and streaming requests and responses.
L7 load balancer implementation, with support for pluggabla strategies, such as RR, Weighted RR, etc.
TLS 1.1 support.

Note: Although hype is somewhat usable, it is still a heavy work in progress.

Example: Hello World!

See hello.rs for a working example. Run with cargo run --bin hello.

async fn hello1(_: Request) -> Result<impl Into<String>, handler::Error> {
    Ok("Hello world!")
}

async fn hello2(_: Request) -> Result<Response, handler::Error> {
    Ok(Response::new(status::OK).with_body("yooo!"))
}

async fn hello3(r: Request) -> Result<String, handler::Error> {
    Ok(format!( "Hello, {}!", r.params.get("name")?))
}

#[tokio::main]
async fn main() {
    hype::logger::init();
    let mut server = Server::new("localhost", 4000);

    // Hello world with inline async block returning String.
    server.route("/hello", handler(|_| async move { Ok("boo!") }));

    // Hello world with function returning string.
    server.route("/hello1", handler(hello1));

    // Hello world with function returning Response.
    server.route("/hello2", handler(hello2));

    // Hello world with path matcher
    server.route("/hello3/:name", handler(hello4));
    server.start().await.unwrap();
}

Example: Stateful services

Use hype::handlers::service to create stateful handlers. See hello.rs for a working example. Run with cargo run --bin app

#[derive(Debug, Clone, Default)]
struct AppState {
    counter: Arc<Mutex<u32>>,
}

#[tokio::main]
async fn main() {
    hype::logger::init();

    let app = AppState {
        counter: Arc::new(Mutex::new(0)),
    };

    let mut server = Server::new("127.0.0.1", 4000);
    server.route_method(
        Method::GET,
        "/counter/get",
        handlers::service(
            |_, s: AppState| async move { Ok(format!("{}\n", s.counter.lock().await)) },
        )
        .with_state(&app),
    );

    server.route_method(
        Method::POST,
        "/counter/inc",
        handlers::service(|_, s: AppState| async move {
            *s.counter.lock().await += 1;
            Ok("OK\n")
        })
        .with_state(&app),
    );

    server.start().await.unwrap();
}

Example: Hello Loadbalancer!

#[tokio::main]
async fn main() {
    hype::logger::init();

    let mut server = Server::new("localhost", 5000);
    server.enable_tls("localhost.crt", "localhost.key");

    let backends: Vec<HttpBackend> = vec![
        HttpBackend::new("localhost:8000")
        HttpBackend::new("localhost:8001")
        HttpBackend::new("localhost:8002")
    ];

    // Create a new load balancer which uses the RoundRobin strategy, and
    // rewrites the Host: header.
    let mut balancer = Http::new(backends, RRPicker::new());
    balancer.rewrite_header("host", "localhost:5000");

    // Create a handler for the balancer and attach it to /balancer. Requests
    // to /balancer will hit one of the backends.
    server.route("/balancer", hype::handlers::Lb::new(balancer));
    server.start().await.unwrap();
}

Running binaries in bin/ and tests in tests/

# Start hello with debug logging
$ RUST_LOG=debug cargo run --bin hello

# Run with TLS (see section below for creating certs)
$ cargo run --bin hello -- -s

# Run balancer
$ vi lbconfig.yaml
$ cargo run --bin balancer

# Run all tests
$ cargo test

# Run specific tests
$ cargo test parser

# Run all tests in a file
# cargo test --test request_test

# Show standard output while running tests
$ cargo test -- --nocapture

# To see logs (via `info!`, `debug!` etc.) in tests, add the following line to the test.

   hype::logger::init()

# Then run the tests with the `-- --nocapture` flag, and optionally set the `RUST_LOG=debug` env var.

# Build docs
$ cargo doc

Generate TLS key and cert file for localhost

$ openssl genrsa -out localhost.key 2048
$ openssl req -new -x509 -sha256 -key localhost.key -out localhost.crt -days 3650

# To test:

curl --insecure https://localhost:4000

License (MIT)

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Status

In Progress

TODO

Implement gzip transfer encoding
Implement wildcard host matching and rewriting
Support path override in LB configuration
Support X-Forwarded-For
Backend healthchecking for balancer targets
Don't propagate hop-by-hop-headers
- Keep-Alive, Transfer-Encoding, TE, Connection, Trailer, Upgrade, Proxy-Authorization and Proxy-Authenticate
- Maybe okay to propagate keep-alive and connection headers.
Cache control headers
Use templating + #include to make file browser look better
- templating engine with https://crates.io/crates/tera
Use https://github.com/dtolnay/thiserror and anyhow::Error for error management

0xfe / hype