admin api: impl RequestHandler for MetricsRequest

src/api/admin/api_server.rs

@@ -5,7 +5,7 @@ use argon2::password_hash::PasswordHash;
 use async_trait::async_trait;
 
 use http::header::{HeaderValue, ACCESS_CONTROL_ALLOW_ORIGIN, AUTHORIZATION};
-use hyper::{body::Incoming as IncomingBody, Request, Response, StatusCode};
+use hyper::{body::Incoming as IncomingBody, Request, Response};
 use serde::{Deserialize, Serialize};
 use tokio::sync::watch;
 
@@ -13,8 +13,6 @@ use opentelemetry::trace::SpanRef;
 
 #[cfg(feature = "metrics")]
 use opentelemetry_prometheus::PrometheusExporter;
-#[cfg(feature = "metrics")]
-use prometheus::{Encoder, TextEncoder};
 
 use garage_model::garage::Garage;
 use garage_rpc::{Endpoint as RpcEndpoint, *};
@@ -100,7 +98,7 @@ pub type ResBody = BoxBody<Error>;
 pub struct AdminApiServer {
 	garage: Arc<Garage>,
 	#[cfg(feature = "metrics")]
-	exporter: PrometheusExporter,
+	pub(crate) exporter: PrometheusExporter,
 	metrics_token: Option<String>,
 	admin_token: Option<String>,
 	pub(crate) background: Arc<BackgroundRunner>,
@@ -146,34 +144,6 @@ impl AdminApiServer {
 			.run_server(bind_addr, Some(0o220), must_exit)
 			.await
 	}
-
-	fn handle_metrics(&self) -> Result<Response<ResBody>, Error> {
-		#[cfg(feature = "metrics")]
-		{
-			use opentelemetry::trace::Tracer;
-
-			let mut buffer = vec![];
-			let encoder = TextEncoder::new();
-
-			let tracer = opentelemetry::global::tracer("garage");
-			let metric_families = tracer.in_span("admin/gather_metrics", |_| {
-				self.exporter.registry().gather()
-			});
-
-			encoder
-				.encode(&metric_families, &mut buffer)
-				.ok_or_internal_error("Could not serialize metrics")?;
-
-			Ok(Response::builder()
-				.status(StatusCode::OK)
-				.header(http::header::CONTENT_TYPE, encoder.format_type())
-				.body(bytes_body(buffer.into()))?)
-		}
-		#[cfg(not(feature = "metrics"))]
-		Err(Error::bad_request(
-			"Garage was built without the metrics feature".to_string(),
-		))
-	}
 }
 
 #[async_trait]
@@ -234,7 +204,7 @@ impl ApiHandler for Arc<AdminApiServer> {
 			AdminApiRequest::Options(req) => req.handle(&self.garage, &self).await,
 			AdminApiRequest::CheckDomain(req) => req.handle(&self.garage, &self).await,
 			AdminApiRequest::Health(req) => req.handle(&self.garage, &self).await,
-			AdminApiRequest::Metrics(_req) => self.handle_metrics(),
+			AdminApiRequest::Metrics(req) => req.handle(&self.garage, &self).await,
 			req => {
 				let res = req.handle(&self.garage, &self).await?;
 				let mut res = json_ok_response(&res)?;

src/api/admin/special.rs

@@ -7,10 +7,13 @@ use http::header::{
 };
 use hyper::{Response, StatusCode};
 
+#[cfg(feature = "metrics")]
+use prometheus::{Encoder, TextEncoder};
+
 use garage_model::garage::Garage;
 use garage_rpc::system::ClusterHealthStatus;
 
-use crate::admin::api::{CheckDomainRequest, HealthRequest, OptionsRequest};
+use crate::admin::api::{CheckDomainRequest, HealthRequest, MetricsRequest, OptionsRequest};
 use crate::admin::api_server::ResBody;
 use crate::admin::error::*;
 use crate::admin::{Admin, RequestHandler};
@@ -35,6 +38,77 @@ impl RequestHandler for OptionsRequest {
 	}
 }
 
+#[async_trait]
+impl RequestHandler for MetricsRequest {
+	type Response = Response<ResBody>;
+
+	async fn handle(
+		self,
+		_garage: &Arc<Garage>,
+		admin: &Admin,
+	) -> Result<Response<ResBody>, Error> {
+		#[cfg(feature = "metrics")]
+		{
+			use opentelemetry::trace::Tracer;
+
+			let mut buffer = vec![];
+			let encoder = TextEncoder::new();
+
+			let tracer = opentelemetry::global::tracer("garage");
+			let metric_families = tracer.in_span("admin/gather_metrics", |_| {
+				admin.exporter.registry().gather()
+			});
+
+			encoder
+				.encode(&metric_families, &mut buffer)
+				.ok_or_internal_error("Could not serialize metrics")?;
+
+			Ok(Response::builder()
+				.status(StatusCode::OK)
+				.header(http::header::CONTENT_TYPE, encoder.format_type())
+				.body(bytes_body(buffer.into()))?)
+		}
+		#[cfg(not(feature = "metrics"))]
+		Err(Error::bad_request(
+			"Garage was built without the metrics feature".to_string(),
+		))
+	}
+}
+
+#[async_trait]
+impl RequestHandler for HealthRequest {
+	type Response = Response<ResBody>;
+
+	async fn handle(
+		self,
+		garage: &Arc<Garage>,
+		_admin: &Admin,
+	) -> Result<Response<ResBody>, Error> {
+		let health = garage.system.health();
+
+		let (status, status_str) = match health.status {
+			ClusterHealthStatus::Healthy => (StatusCode::OK, "Garage is fully operational"),
+			ClusterHealthStatus::Degraded => (
+				StatusCode::OK,
+				"Garage is operational but some storage nodes are unavailable",
+			),
+			ClusterHealthStatus::Unavailable => (
+				StatusCode::SERVICE_UNAVAILABLE,
+				"Quorum is not available for some/all partitions, reads and writes will fail",
+			),
+		};
+		let status_str = format!(
+			"{}\nConsult the full health check API endpoint at /v2/GetClusterHealth for more details\n",
+			status_str
+		);
+
+		Ok(Response::builder()
+			.status(status)
+			.header(http::header::CONTENT_TYPE, "text/plain")
+			.body(string_body(status_str))?)
+	}
+}
+
 #[async_trait]
 impl RequestHandler for CheckDomainRequest {
 	type Response = Response<ResBody>;
@@ -108,37 +182,3 @@ async fn check_domain(garage: &Arc<Garage>, domain: &str) -> Result<bool, Error>
 		None => Ok(false),
 	}
 }
-
-#[async_trait]
-impl RequestHandler for HealthRequest {
-	type Response = Response<ResBody>;
-
-	async fn handle(
-		self,
-		garage: &Arc<Garage>,
-		_admin: &Admin,
-	) -> Result<Response<ResBody>, Error> {
-		let health = garage.system.health();
-
-		let (status, status_str) = match health.status {
-			ClusterHealthStatus::Healthy => (StatusCode::OK, "Garage is fully operational"),
-			ClusterHealthStatus::Degraded => (
-				StatusCode::OK,
-				"Garage is operational but some storage nodes are unavailable",
-			),
-			ClusterHealthStatus::Unavailable => (
-				StatusCode::SERVICE_UNAVAILABLE,
-				"Quorum is not available for some/all partitions, reads and writes will fail",
-			),
-		};
-		let status_str = format!(
-			"{}\nConsult the full health check API endpoint at /v2/GetClusterHealth for more details\n",
-			status_str
-		);
-
-		Ok(Response::builder()
-			.status(status)
-			.header(http::header::CONTENT_TYPE, "text/plain")
-			.body(string_body(status_str))?)
-	}
-}