1use std::{
7 borrow::Cow,
8 task::{Context, Poll},
9};
10
11use tower_service::Service;
12
13use crate::{LogContext, LogContextFuture};
14
15pub struct LogContextService<S, R> {
18 inner: S,
19 tagger: fn(&R) -> Cow<'static, str>,
20}
21
22impl<S: Clone, R> Clone for LogContextService<S, R> {
23 fn clone(&self) -> Self {
24 Self {
25 inner: self.inner.clone(),
26 tagger: self.tagger,
27 }
28 }
29}
30
31impl<S, R> LogContextService<S, R> {
32 pub fn new(inner: S, tagger: fn(&R) -> Cow<'static, str>) -> Self {
33 Self { inner, tagger }
34 }
35}
36
37impl<S, R> Service<R> for LogContextService<S, R>
38where
39 S: Service<R>,
40{
41 type Response = S::Response;
42 type Error = S::Error;
43 type Future = LogContextFuture<S::Future>;
44
45 fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
46 self.inner.poll_ready(cx)
47 }
48
49 fn call(&mut self, req: R) -> Self::Future {
50 let tag = (self.tagger)(&req);
51 let log_context = LogContext::new(tag);
52 log_context.run(|| self.inner.call(req))
53 }
54}