Add grpc health service.

Signed-off-by: Michael Nelson <minelson@vmware.com>

chart/kubeapps/templates/kubeappsapis/deployment.yaml

@@ -259,6 +259,9 @@ spec:
           env:
             - name: OCI_CATALOG_PORT
               value: {{ .Values.ociCatalog.containerPorts.http | quote }}
+            - name: RUST_LOG
+              # Use info,pinniped_proxy::pinniped=debug for module control.
+              value: info
             {{- if .Values.ociCatalog.extraEnvVars }}
             {{- include "common.tplvalues.render" (dict "value" .Values.ociCatalog.extraEnvVars "context" $) | nindent 12 }}
             {{- end }}

cmd/oci-catalog/Cargo.toml

@@ -18,6 +18,7 @@ serde_json = "1.0"
 tokio = { version = "1.30", features = ["macros", "rt-multi-thread"] }
 tokio-stream = "0.1"
 tonic = "0.9"
+tonic-health = "0.9.2"
 url = "2.4"
 
 [build-dependencies]

cmd/oci-catalog/src/main.rs

@@ -80,8 +80,15 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
     let addr = ([0, 0, 0, 0], opt.port).into();
     let kubeapps_oci_catalog = KubeappsOCICatalog::default();
 
+    let (mut _health_reporter, health_service) = tonic_health::server::health_reporter();
+    // TODO(absoludity): Need to implement a decent check for the actual service
+    // that won't kill us with request quotas.  See
+    // https://github.com/hyperium/tonic/blob/master/examples/src/health/server.rs
+    // for an example setup.
+
     let server = Server::builder()
         .add_service(OciCatalogServer::new(kubeapps_oci_catalog))
+        .add_service(health_service)
         .serve(addr);
     log::info!("listening for gRPC requests at {}", addr);
     server.await.expect("unexpected error while serving");