How to trigger ConcurrencyLimitLayer?

[goldwind-ting]

use axum::{
    routing::get,
    response::IntoResponse,
    Router,
};
use tracing::info;
use tower::limit::ConcurrencyLimitLayer;
use tower_http::trace::TraceLayer;


async fn handle() -> impl IntoResponse {
    "OK"
}

#[tokio::main]
async fn main() {
    tracing_subscriber::fmt::init();
    let middleware = tower::ServiceBuilder::new()
        .layer(TraceLayer::new_for_http())
        .layer(ConcurrencyLimitLayer::new(1));

    let app = Router::new()
        .route("/api/v1", get(handle))
        .layer(middleware);

    let addr = &"[::]:23818".parse().unwrap();
    info!("listening on {}", addr);
    axum::Server::bind(addr)
        .serve(app.into_make_service())
        .await.unwrap();
}

I executed ab -c 20 -k -t 10 http://localhost:23818/api/v1, but it can not trigger ConcurrencyLimitLayer and panic expected.

[davidpdrsn]

Why would you expect a panic? ConcurrencyLimitLayer doesn't panic when it's at capacity but returns Pending from Service::poll_ready.

[goldwind-ting]

Why would you expect a panic? ConcurrencyLimitLayer doesn't panic when it's at capacity but returns Pending from Service::poll_ready.

sorry, my bad.