Add outbound index metrics to the policy controller

policy-controller/k8s/index/src/outbound.rs

@@ -1,3 +1,3 @@
 pub mod index;
 
-pub use index::{Index, ServiceRef, SharedIndex};
+pub use index::{metrics, Index, ServiceRef, SharedIndex};

policy-controller/k8s/index/src/outbound/index.rs

@@ -25,6 +25,8 @@ pub struct Index {
     service_info: HashMap<ServiceRef, ServiceInfo>,
 }
 
+pub mod metrics;
+
 pub type SharedIndex = Arc<RwLock<Index>>;
 
 #[derive(Debug, Clone, Hash, PartialEq, Eq)]

policy-controller/k8s/index/src/outbound/index/metrics.rs

@@ -0,0 +1,67 @@
+use prometheus_client::{
+    collector::Collector,
+    encoding::{DescriptorEncoder, EncodeMetric},
+    metrics::{gauge::ConstGauge, MetricType},
+    registry::Registry,
+};
+
+use super::SharedIndex;
+
+#[derive(Debug)]
+struct Instrumented(SharedIndex);
+
+pub fn register(reg: &mut Registry, index: SharedIndex) {
+    reg.register_collector(Box::new(Instrumented(index)));
+}
+
+impl Collector for Instrumented {
+    fn encode(&self, mut encoder: DescriptorEncoder<'_>) -> Result<(), std::fmt::Error> {
+        let this = self.0.read();
+
+        let service_encoder = encoder.encode_descriptor(
+            "service_index_size",
+            "The number of entires in service index",
+            None,
+            MetricType::Gauge,
+        )?;
+        let services = ConstGauge::new(this.services_by_ip.len() as u32);
+        services.encode(service_encoder)?;
+
+        let service_info_encoder = encoder.encode_descriptor(
+            "service_info_index_size",
+            "The number of entires in the service info index",
+            None,
+            MetricType::Gauge,
+        )?;
+        let service_infos = ConstGauge::new(this.service_info.len() as u32);
+        service_infos.encode(service_info_encoder)?;
+
+        let mut service_route_encoder = encoder.encode_descriptor(
+            "service_route_index_size",
+            "The number of entires in the service route index",
+            None,
+            MetricType::Gauge,
+        )?;
+        for (ns, index) in &this.namespaces.by_ns {
+            let labels = vec![("namespace", ns.as_str())];
+            let service_routes = ConstGauge::new(index.service_routes.len() as u32);
+            let service_route_encoder = service_route_encoder.encode_family(&labels)?;
+            service_routes.encode(service_route_encoder)?;
+        }
+
+        let mut service_port_route_encoder = encoder.encode_descriptor(
+            "service_port_route_index_size",
+            "The number of entires in the service port route index",
+            None,
+            MetricType::Gauge,
+        )?;
+        for (ns, index) in &this.namespaces.by_ns {
+            let labels = vec![("namespace", ns.as_str())];
+            let service_port_routes = ConstGauge::new(index.service_port_routes.len() as u32);
+            let service_port_route_encoder = service_port_route_encoder.encode_family(&labels)?;
+            service_port_routes.encode(service_port_route_encoder)?;
+        }
+
+        Ok(())
+    }
+}

policy-controller/src/main.rs

@@ -149,6 +149,10 @@ async fn main() -> Result<()> {
     let status_metrics = status::ControllerMetrics::register(resource_status);
     let status_index_metrcs = status::IndexMetrics::register(resource_status);
 
+    outbound::metrics::register(
+        prom.sub_registry_with_prefix("outbound_index"),
+        outbound_index.clone(),
+    );
     inbound::metrics::register(
         prom.sub_registry_with_prefix("inbound_index"),
         inbound_index.clone(),