follow JS promise model in cf-worker build

Signed-off-by: eternal-flame-AD <yume@yumechi.jp>

src/fetch/mod.rs

@@ -540,16 +540,15 @@ pub mod cf_worker {
             let abs = abc.signal();
             let req = Fetch::Request(req);
 
-            let mut resp_fut = std::pin::pin!(req
+            worker::wasm_bindgen_futures::spawn_local(async move {
+                worker::Delay::from(Duration::from_secs(5)).await;
+                abc.abort();
+            });
+
+            let resp = std::pin::pin!(req
                 .send_with_signal(&abs)
-                .map_err(ErrorResponse::worker_fetch_error));
-
-            let timeout = std::pin::pin!(worker::Delay::from(Duration::from_secs(5)));
-
-            let resp = futures::select! {
-                resp = resp_fut => resp?,
-                _ = timeout.fuse() => return Err(ErrorResponse::upstream_timeout()),
-            };
+                .map_err(ErrorResponse::worker_fetch_error))
+            .await?;
 
             if resp.status_code() == 301 || resp.status_code() == 302 {
                 if let Ok(Some(location)) = resp.headers().get("location") {

wrangler.toml

@@ -4,3 +4,7 @@ compatibility_date = "2024-11-11"
 
 [build]
 command = "cargo install -q worker-build && worker-build --release --features cf-worker"
+
+[observability]
+enabled = true
+head_sampling_rate = 1