chore(examples/hyper): port to hyper 1.x (#195)

Based on #184 Co-authored-by: Jun Kurihara <[email protected]> Signed-off-by: Tamas Levai <[email protected]>
prometheus · May 13, 2024 · bf196d7 · bf196d7
1 parent b462e61
commit bf196d7
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Showing 2 changed files with 45 additions and 21 deletions.
diff --git a/Cargo.toml b/Cargo.toml
@@ -35,7 +35,9 @@ rand = "0.8.4"
 tide = "0.16"
 actix-web = "4"
 tokio = { version = "1", features = ["rt-multi-thread", "net", "macros", "signal"] }
-hyper = { version = "0.14.16", features = ["server", "http1", "tcp"] }
+hyper = { version = "1.3.1", features = ["server", "http1"] }
+hyper-util = { version = "0.1.3", features = ["tokio"] }
+http-body-util = "0.1.1"
 
 [build-dependencies]
 prost-build = { version = "0.11.0", optional = true }

diff --git a/examples/hyper.rs b/examples/hyper.rs
@@ -1,7 +1,11 @@
+use http_body_util::{combinators, BodyExt, Full};
 use hyper::{
-    service::{make_service_fn, service_fn},
-    Body, Request, Response, Server,
+    body::{Bytes, Incoming},
+    server::conn::http1,
+    service::service_fn,
+    Request, Response,
 };
+use hyper_util::rt::TokioIo;
 use prometheus_client::{encoding::text::encode, metrics::counter::Counter, registry::Registry};
 use std::{
     future::Future,
@@ -10,7 +14,11 @@ use std::{
     pin::Pin,
     sync::Arc,
 };
-use tokio::signal::unix::{signal, SignalKind};
+use tokio::{
+    net::TcpListener,
+    pin,
+    signal::unix::{signal, SignalKind},
+};
 
 #[tokio::main]
 async fn main() {
@@ -31,39 +39,48 @@ async fn main() {
 
 /// Start a HTTP server to report metrics.
 pub async fn start_metrics_server(metrics_addr: SocketAddr, registry: Registry) {
-    let mut shutdown_stream = signal(SignalKind::terminate()).unwrap();
-
     eprintln!("Starting metrics server on {metrics_addr}");
 
     let registry = Arc::new(registry);
-    Server::bind(&metrics_addr)
-        .serve(make_service_fn(move |_conn| {
-            let registry = registry.clone();
-            async move {
-                let handler = make_handler(registry);
-                Ok::<_, io::Error>(service_fn(handler))
+
+    let tcp_listener = TcpListener::bind(metrics_addr).await.unwrap();
+    let server = http1::Builder::new();
+    while let Ok((stream, _)) = tcp_listener.accept().await {
+        let mut shutdown_stream = signal(SignalKind::terminate()).unwrap();
+        let io = TokioIo::new(stream);
+        let server_clone = server.clone();
+        let registry_clone = registry.clone();
+        tokio::task::spawn(async move {
+            let conn = server_clone.serve_connection(io, service_fn(make_handler(registry_clone)));
+            pin!(conn);
+            tokio::select! {
+                _ = conn.as_mut() => {}
+                _ = shutdown_stream.recv() => {
+                    conn.as_mut().graceful_shutdown();
+                }
             }
-        }))
-        .with_graceful_shutdown(async move {
-            shutdown_stream.recv().await;
-        })
-        .await
-        .unwrap();
+        });
+    }
 }
 
+/// Boxed HTTP body for responses
+type BoxBody = combinators::BoxBody<Bytes, hyper::Error>;
+
 /// This function returns a HTTP handler (i.e. another function)
 pub fn make_handler(
     registry: Arc<Registry>,
-) -> impl Fn(Request<Body>) -> Pin<Box<dyn Future<Output = io::Result<Response<Body>>> + Send>> {
+) -> impl Fn(Request<Incoming>) -> Pin<Box<dyn Future<Output = io::Result<Response<BoxBody>>> + Send>>
+{
     // This closure accepts a request and responds with the OpenMetrics encoding of our metrics.
-    move |_req: Request<Body>| {
+    move |_req: Request<Incoming>| {
         let reg = registry.clone();
+
         Box::pin(async move {
             let mut buf = String::new();
             encode(&mut buf, &reg.clone())
                 .map_err(|e| std::io::Error::new(std::io::ErrorKind::Other, e))
                 .map(|_| {
-                    let body = Body::from(buf);
+                    let body = full(Bytes::from(buf));
                     Response::builder()
                         .header(
                             hyper::header::CONTENT_TYPE,
@@ -75,3 +92,8 @@ pub fn make_handler(
         })
     }
 }
+
+/// helper function to build a full boxed body
+pub fn full(body: Bytes) -> BoxBody {
+    Full::new(body).map_err(|never| match never {}).boxed()
+}