Is there a way to redirect from www to non-www?

[iggyzuk]

Summary

I want to force non-www for my website e.g. https://www.example.com/hey -> https://example.com/hey
Is there already something like this? If not I wonder what's a good way to implement it, maybe as a middleware?
Thanks!

axum version

0.7.4

[jplatte]

Are you talking about a case where requests to both go to the same axum server? I'd usually do this one level higher at the nginx or whatever reverse proxy you have in front that also does TLS termination.

If you don't have one at all and are receiving TLS traffic directly (e.g. via axum-server), you can indeed write a middleware for this. I'd recommend axum::middleware::from_fn with a function that checks the host header, returns a Redirect if it matches the www. subdomain, or runs the Next service otherwise.

[iggyzuk]

Exactly. I'm using fly.io, I've looked around but I could not find a way to do it.
I'll give the middleware a go, doesn't sound that difficult. Thanks!

[iggyzuk]

In case anyone is looking for the code.
Add it to the Router with: app.layer(axum::middleware::from_fn(redirect_to_non_www))
AppError is like in example: https://github.com/tokio-rs/axum/blob/main/examples/anyhow-error-response/src/main.rs

pub async fn redirect_to_non_www(request: Request, next: Next) -> Result<impl IntoResponse, AppError> {
    let host = request.headers().get("host").and_then(|h| h.to_str().ok());
    if let Some(host) = host {
        if host.starts_with("www.") {
            let uri = request.uri().clone();

            let mut parts = uri.into_parts();
            parts.scheme = Some(Scheme::HTTPS);
            parts.authority = Some(http::uri::Authority::from_str(
                host.trim_start_matches("www."),
            )?);

            let new_uri = http::Uri::from_parts(parts)?;

            let response = Response::builder()
                .status(StatusCode::MOVED_PERMANENTLY)
                .header("Location", new_uri.to_string())
                .body(Body::empty())?;

            return Ok(response);
        }
    }
    Ok(next.run(request).await)
}