Middleware that sets response header based on request header

[dspicher]

I would like to implement a middleware that sets a response header to the identical value as the one received in the request.

Is there an easier way to achieve this than the one discussed under the scope of general state sharing here?

[davidpdrsn]

You can use https://docs.rs/tower-http/latest/tower_http/propagate_header/index.html.

Otherwise you can do this:

async fn propagate_header<B>(req: Request<B>, next: Next<B>) -> Response {
    let header = req.headers().get("...").unwrap();
    let mut res = next.run(req).await;
    res.headers_mut().insert("key", header);
    res
}

Router::new().route(...).middleware(axum::middleware::from_fn(propagate_header));

[dspicher]

I knew my searching skills were failing me 🙈 thank you so much for the quick answer! ❤️