tower_http::trace::TraceLayer.on_eos can not be called

[kobe2000]

• I have looked for existing issues (including closed) about this

Bug Report

Version

• axum 0.7.2
• tower 0.4.13
• tower-http 0.5.0
• tokio 1.35.1
• tracing 0.1.40
• tracing-subscriber 0.3.18

Platform

Windows x64

Description

I want to measure the whole time of http server processing (including network IO), so I try to use TraceLayer to log the time like following code:

let app = Router::new()
        .route("/api", post(api))
        .layer(TraceLayer::new_for_http().on_eos(|trailers: Option<&HeaderMap>, stream_duration: Duration, _span: &Span| {
            println!("stream closed after {:?}", stream_duration)
        }))

But I can not see anying on console, please help.

Thank you!

[davidpdrsn]

That's not what on_eos is intended for. In order to get accurate measurements, including IO, you'll have to use hyper. I'm not sure which APIs hyper has to measure this kinda of stuff but try asking in hyper's discord channel.