Pencil: A Microframework Inspired by Flask for Rust

Post by fredsir » Tue, Mar 08, 2016, 9:36 PM UTC

TheHydroImpulse wrote: post #7

jdreaver wrote: post #5

I've found that whenever I start a small web project in a new language, I always look for the "Flask" of that language. I love using a framework that gives the bare essentials and nothing else. I don't use Rust, but your code examples look great! I understand that Rust has less opportunity for "magic" to clean things up (for example, in Python you can use a decorator to specify a route for a function), but otherwise…

There's probably some opportunity to use custom annotations in Rust to achieve the same thing. #[route("/foobar")] fn user(_: &mut Request) -> PencilResult { // ... } However, procedural macros are unstable, but Rust is able to do amazing things with macros.

Post by TheHydroImpulse » Tue, Mar 08, 2016, 9:58 PM UTC

fredsir wrote: post #21

TheHydroImpulse wrote: post #7

Earlier quoted context omitted.

There's probably some opportunity to use custom annotations in Rust to achieve the same thing. #[route("/foobar")] fn user(_: &mut Request) -> PencilResult { // ... } However, procedural macros are unstable, but Rust is able to do amazing things with macros.

I know very little Rust, but I was actually looking at how this could be done in Rust some time ago, but I didn't get anything working. All the routes (e.g. /foobar and accompanying function) needs to be collected by the "router" somehow which begs for a global route-container that the route macro (like Flasks route decorator) would need to add routes to, similar to how it is done is Flask, and, well, yeah, I couldn'…

    struct RouteUser {
        route: &'static str,
        f: fn(_: &mut Request) -> PencilResult
    }

    #[route("/user")]
    fn user(_: &mut Request) -> PencilResult {}

    fn user() -> RouteUser {
        // The actual function the user wrote:
        fn user(_: &mut Request) -> PencilResult {
            // ...
        }

        RouteUser {
            // Generated from the annotation argument
            route: "/user",
            f: user
        }
    }

    trait Route {}

    impl Route for RouteUser {}

    app.route(user());

    fn route(r: R) where R: Route {
        // ...
    }

Post by bsharitt » Tue, Mar 08, 2016, 10:05 PM UTC

jdreaver wrote: post #5

I've found that whenever I start a small web project in a new language, I always look for the "Flask" of that language. I love using a framework that gives the bare essentials and nothing else. I don't use Rust, but your code examples look great! I understand that Rust has less opportunity for "magic" to clean things up (for example, in Python you can use a decorator to specify a route for a function), but otherwise…

Post by steveklabnik » Tue, Mar 08, 2016, 10:29 PM UTC

maxcan wrote: post #16

Great start. Instead of numeric codes, perhaps use an enum for all the acceptable status codes? As Jane Street Says, make illegal state unrepresentable.

Post by zanny » Tue, Mar 08, 2016, 10:50 PM UTC

jdreaver wrote: post #5

I've found that whenever I start a small web project in a new language, I always look for the "Flask" of that language. I love using a framework that gives the bare essentials and nothing else. I don't use Rust, but your code examples look great! I understand that Rust has less opportunity for "magic" to clean things up (for example, in Python you can use a decorator to specify a route for a function), but otherwise…