Example of context with web server like Axum

[pbouzakis]

I'm struggling to implement context in my application and was wondering if we could get an example of using context in more typical application running a web server like axum.

[Pitasi]

Hey there! Sorry to not have a proper Axum example, you're right, I'll make one as soon as I can :)

The idea would be something like this:

pub async fn your_handler() -> impl IntoResponse {
    rscx::axum::render(async move {
        html! {
            <h1>hello world</h1>
        }.await
    })
    .await
}

instead of <h1> use your custom components, and inside their body you can use rscx::provide_context() and rscx::use_context() to respectively register a new context or access one (like I did here https://github.com/Pitasi/rscx/blob/main/rscx/examples/context.rs#L41).

Does this help?

[pbouzakis]

I ended up with a solution by building my own context rather than using rsxc context.

Something like this

use axum::{http::Request, middleware::Next, response::Response};
use std::future::Future;

#[derive(Clone)]
pub struct Context {
    pub page_url: String,
}

tokio::task_local! {
    pub(crate) static CONTEXT: Context;
}

pub async fn context_provider_layer<B>(request: Request<B>, next: Next<B>) -> Response {
    let context = Context {
        page_url: request.uri().path().to_string(),
    };

    // Set the context for this request.
    provide_context(context, next.run(request)).await
}

pub async fn provide_context<F: Future<Output = O>, O>(context: Context, f: F) -> O {
    CONTEXT.scope(context, f).await
}

pub fn context() -> Option<Context> {
    CONTEXT.try_with(|c| c.clone()).ok()
}

I then add the context_provider_layer as middleware to axum, and then inside any component, I can call context.

Looking forward to your update!

[npetrangelo]

I was able to throw a component into an Axum handler like this

let router = Router::new()
    .route("/", get(|| async { Html(kinbox().await) }))
    .route("/styles.css", get(|| async { Css(getCss().await) }));