4 files changed, 77 insertions, 10 deletions
diff --git a/src/admin/Cargo.toml b/src/admin/Cargo.toml
index 6f646869..b6bf2b3b 100644
--- a/src/admin/Cargo.toml
+++ b/src/admin/Cargo.toml
@@ -16,12 +16,15 @@ path = "lib.rs"
 garage_model = { version = "0.6.0", path = "../model" }
 garage_util = { version = "0.6.0", path = "../util" }
 
+hex = "0.4"
+
 futures = "0.3"
 futures-util = "0.3"
 http = "0.2"
 hyper = "0.14"
-log = "0.4"
+tracing = "0.1.30"
 
-opentelemetry = "0.17"
+opentelemetry = { version = "0.17", features = [ "rt-tokio" ] }
 opentelemetry-prometheus = "0.10"
+opentelemetry-otlp = "0.10"
 prometheus = "0.13"
diff --git a/src/admin/lib.rs b/src/admin/lib.rs
index f1e8ddd7..b5b0775b 100644
--- a/src/admin/lib.rs
+++ b/src/admin/lib.rs
@@ -1,5 +1,6 @@
 //! Crate for handling the admin and metric HTTP APIs
 #[macro_use]
-extern crate log;
+extern crate tracing;
 
 pub mod metrics;
+pub mod tracing_setup;
diff --git a/src/admin/metrics.rs b/src/admin/metrics.rs
index 44fd4cb2..e12373ab 100644
--- a/src/admin/metrics.rs
+++ b/src/admin/metrics.rs
@@ -1,20 +1,26 @@
+use std::convert::Infallible;
+use std::sync::Arc;
+use std::time::SystemTime;
+
+use futures::future::*;
 use hyper::{
 	header::CONTENT_TYPE,
 	service::{make_service_fn, service_fn},
 	Body, Method, Request, Response, Server,
 };
+
 use opentelemetry::{
 	global,
 	metrics::{BoundCounter, BoundValueRecorder},
+	trace::{FutureExt, TraceContextExt, Tracer},
+	Context,
 };
 use opentelemetry_prometheus::PrometheusExporter;
+
 use prometheus::{Encoder, TextEncoder};
-use std::convert::Infallible;
-use std::sync::Arc;
-use std::time::SystemTime;
 
-use futures::future::*;
 use garage_model::garage::Garage;
+use garage_util::data::*;
 use garage_util::error::Error as GarageError;
 
 // serve_req on metric endpoint
@@ -22,7 +28,7 @@ async fn serve_req(
 	req: Request<Body>,
 	admin_server: Arc<AdminServer>,
 ) -> Result<Response<Body>, hyper::Error> {
-	println!("Receiving request at path {}", req.uri());
+	info!("Receiving request at path {}", req.uri());
 	let request_start = SystemTime::now();
 
 	admin_server.metrics.http_counter.add(1);
@@ -31,7 +37,12 @@ async fn serve_req(
 		(&Method::GET, "/metrics") => {
 			let mut buffer = vec![];
 			let encoder = TextEncoder::new();
-			let metric_families = admin_server.exporter.registry().gather();
+
+			let tracer = opentelemetry::global::tracer("garage");
+			let metric_families = tracer.in_span("admin/gather_metrics", |_| {
+				admin_server.exporter.registry().gather()
+			});
+
 			encoder.encode(&metric_families, &mut buffer).unwrap();
 			admin_server
 				.metrics
@@ -112,7 +123,22 @@ impl AdminServer {
 			// `service_fn` is a helper to convert a function that
 			// returns a Response into a `Service`.
 			async move {
-				Ok::<_, Infallible>(service_fn(move |req| serve_req(req, admin_server.clone())))
+				Ok::<_, Infallible>(service_fn(move |req| {
+					let tracer = opentelemetry::global::tracer("garage");
+					let uuid = gen_uuid();
+					let span = tracer
+						.span_builder("admin/request")
+						.with_trace_id(
+							opentelemetry::trace::TraceId::from_hex(&hex::encode(
+								&uuid.as_slice()[..16],
+							))
+							.unwrap(),
+						)
+						.start(&tracer);
+
+					serve_req(req, admin_server.clone())
+						.with_context(Context::current_with_span(span))
+				}))
 			}
 		});
 
diff --git a/src/admin/tracing_setup.rs b/src/admin/tracing_setup.rs
new file mode 100644
index 00000000..83fa5622
--- /dev/null
+++ b/src/admin/tracing_setup.rs
@@ -0,0 +1,37 @@
+use std::time::Duration;
+
+use opentelemetry::sdk::{
+	trace::{self, IdGenerator, Sampler},
+	Resource,
+};
+use opentelemetry::KeyValue;
+use opentelemetry_otlp::WithExportConfig;
+
+use garage_util::data::*;
+use garage_util::error::*;
+
+pub fn init_tracing(export_to: &str, node_id: Uuid) -> Result<(), Error> {
+	let node_id = hex::encode(&node_id.as_slice()[..8]);
+
+	opentelemetry_otlp::new_pipeline()
+		.tracing()
+		.with_exporter(
+			opentelemetry_otlp::new_exporter()
+				.tonic()
+				.with_endpoint(export_to)
+				.with_timeout(Duration::from_secs(3)),
+		)
+		.with_trace_config(
+			trace::config()
+				.with_id_generator(IdGenerator::default())
+				.with_sampler(Sampler::TraceIdRatioBased(0.01f64))
+				.with_resource(Resource::new(vec![
+					KeyValue::new("service.name", "garage"),
+					KeyValue::new("service.instance.id", node_id),
+				])),
+		)
+		.install_batch(opentelemetry::runtime::Tokio)
+		.ok_or_message("Unable to initialize tracing")?;
+
+	Ok(())
+}