# Sputnik A microframework based on [Hyper](https://hyper.rs/) providing traits to: * extend `http::request::Parts` with query parameter deserialization & cookie parsing * extend `hyper::Body` with form deserialization (and optional [CSRF](https://en.wikipedia.org/wiki/Cross-site_request_forgery) protection) * extend `http::response::Builder` with methods to set & delete cookies and set the Content-Type Furthermore Sputnik provides what's necessary to implement [signed & expiring cookies](#signed--expiring-cookies) with the expiry date encoded into the signed cookie value, providing a more lightweight alternative to JWT if you don't need interoperability. Sputnik does **not** handle routing. For most web applications `match`ing on (method, path) suffices. If you need path variables, you can use one of the many [router crates](https://crates.io/keywords/router). Sputnik encourages you to create your own error enum and implement `From` conversions for every error type, which you want to short-circuit with the `?` operator. This can be easily done with [thiserror](https://crates.io/crates/thiserror) because Sputnik restricts its error types to the `'static` lifetime. ## Example ```rust use std::convert::Infallible; use hyper::service::{service_fn, make_service_fn}; use hyper::{Method, Server, StatusCode, Body}; use hyper::http::request::Parts; use hyper::http::response::Builder; use serde::Deserialize; use sputnik::{mime, request::{SputnikParts, SputnikBody}, response::SputnikBuilder}; use sputnik::request::CsrfProtectedFormError; type Response = hyper::Response; #[derive(thiserror::Error, Debug)] enum Error { #[error("page not found")] NotFound(String), #[error("{0}")] CsrfError(#[from] CsrfProtectedFormError) } fn render_error(err: Error) -> (StatusCode, String) { match err { Error::NotFound(msg) => (StatusCode::NOT_FOUND, msg), Error::CsrfError(err) => (StatusCode::BAD_REQUEST, err.to_string()), } } async fn route(req: &mut Parts, body: Body) -> Result { match (&req.method, req.uri.path()) { (&Method::GET, "/form") => Ok(get_form(req)), (&Method::POST, "/form") => post_form(req, body).await, _ => return Err(Error::NotFound("page not found".to_owned())) } } fn get_form(req: &mut Parts) -> Response { let mut response = Builder::new(); let csrf_input = req.csrf_html_input(&mut response); response.content_type(mime::TEXT_HTML).body( format!("
{}
", csrf_input).into() ).unwrap() } #[derive(Deserialize)] struct FormData {text: String} async fn post_form(req: &mut Parts, body: Body) -> Result { let msg: FormData = body.into_form_csrf(req).await?; Ok(Builder::new().body( format!("hello {}", msg.text).into() ).unwrap()) } async fn service(req: hyper::Request) -> Result, Infallible> { let (mut parts, body) = req.into_parts(); match route(&mut parts, body).await { Ok(res) => Ok(res), Err(err) => { let (code, message) = render_error(err); // you can easily wrap or log errors here Ok(hyper::Response::builder().status(code).body(message.into()).unwrap()) } } } #[tokio::main] async fn main() { let service = make_service_fn(move |_| { async move { Ok::<_, hyper::Error>(service_fn(move |req| { service(req) })) } }); let addr = ([127, 0, 0, 1], 8000).into(); let server = Server::bind(&addr).serve(service); println!("Listening on http://{}", addr); server.await; } ``` ## Signed & expiring cookies After a successful authentication you can build a session id cookie for example as follows: ```rust let expiry_date = OffsetDateTime::now_utc() + Duration::hours(24); let mut cookie = Cookie::new("userid", key.sign( &encode_expiring_claim(&userid, expiry_date) )); cookie.set_secure(Some(true)); cookie.set_expires(expiry_date); cookie.set_same_site(SameSite::Lax); resp.set_cookie(cookie); ``` This session id cookie can then be retrieved and verified as follows: ```rust let userid = req.cookies().get("userid") .ok_or_else(|| "expected userid cookie".to_owned()) .and_then(|cookie| key.verify(cookie.value()) .and_then(|value| decode_expiring_claim(value).map_err(|e| format!("failed to decode userid cookie: {}", e))); ``` Tip: If you want to store multiple claims in the cookie, you can (de)serialize a struct with [serde_json](https://docs.serde.rs/serde_json/). This approach can pose a lightweight alternative to JWT, if you don't care about the standardization aspect.