Make policy controller watches optional

Signed-off-by: Alex Leong <[email protected]>
linkerd · Jul 30, 2024 · 7d5ddd8 · 7d5ddd8
1 parent 99fd7e1
commit 7d5ddd8
Showing 1 changed file with 52 additions and 21 deletions.
diff --git a/policy-controller/src/main.rs b/policy-controller/src/main.rs
@@ -247,33 +247,51 @@ async fn main() -> Result<()> {
             .instrument(info_span!("networkauthentications")),
     );
 
-    let http_routes = runtime.watch_all::<k8s::policy::HttpRoute>(watcher::Config::default());
     let http_routes_indexes = IndexList::new(inbound_index.clone())
         .push(outbound_index.clone())
         .push(status_index.clone())
         .shared();
-    tokio::spawn(
-        kubert::index::namespaced(http_routes_indexes.clone(), http_routes)
-            .instrument(info_span!("httproutes.policy.linkerd.io")),
-    );
 
-    let gateway_http_routes =
-        runtime.watch_all::<k8s_gateway_api::HttpRoute>(watcher::Config::default());
-    tokio::spawn(
-        kubert::index::namespaced(http_routes_indexes, gateway_http_routes)
-            .instrument(info_span!("httproutes.gateway.networking.k8s.io")),
-    );
+    if api_resource_exists::<k8s::policy::HttpRoute>(&runtime.client()).await {
+        let http_routes = runtime.watch_all::<k8s::policy::HttpRoute>(watcher::Config::default());
 
-    let gateway_grpc_routes =
-        runtime.watch_all::<k8s_gateway_api::GrpcRoute>(watcher::Config::default());
-    let gateway_grpc_routes_indexes = IndexList::new(outbound_index.clone())
-        .push(inbound_index.clone())
-        .push(status_index.clone())
-        .shared();
-    tokio::spawn(
-        kubert::index::namespaced(gateway_grpc_routes_indexes.clone(), gateway_grpc_routes)
-            .instrument(info_span!("grpcroutes.gateway.networking.k8s.io")),
-    );
+        tokio::spawn(
+            kubert::index::namespaced(http_routes_indexes.clone(), http_routes)
+                .instrument(info_span!("httproutes.policy.linkerd.io")),
+        );
+    } else {
+        tracing::warn!("httproutes.policy.linkerd.io resource kind not found, skipping watches");
+    }
+
+    if api_resource_exists::<k8s_gateway_api::HttpRoute>(&runtime.client()).await {
+        let gateway_http_routes =
+            runtime.watch_all::<k8s_gateway_api::HttpRoute>(watcher::Config::default());
+        tokio::spawn(
+            kubert::index::namespaced(http_routes_indexes, gateway_http_routes)
+                .instrument(info_span!("httproutes.gateway.networking.k8s.io")),
+        );
+    } else {
+        tracing::warn!(
+            "httproutes.gateway.networking.k8s.io resource kind not found, skipping watches"
+        );
+    }
+
+    if api_resource_exists::<k8s_gateway_api::GrpcRoute>(&runtime.client()).await {
+        let gateway_grpc_routes =
+            runtime.watch_all::<k8s_gateway_api::GrpcRoute>(watcher::Config::default());
+        let gateway_grpc_routes_indexes = IndexList::new(outbound_index.clone())
+            .push(inbound_index.clone())
+            .push(status_index.clone())
+            .shared();
+        tokio::spawn(
+            kubert::index::namespaced(gateway_grpc_routes_indexes.clone(), gateway_grpc_routes)
+                .instrument(info_span!("grpcroutes.gateway.networking.k8s.io")),
+        );
+    } else {
+        tracing::warn!(
+            "grpcroutes.gateway.networking.k8s.io resource kind not found, skipping watches"
+        );
+    }
 
     let services = runtime.watch_all::<k8s::Service>(watcher::Config::default());
     let services_indexes = IndexList::new(outbound_index.clone())
@@ -435,3 +453,16 @@ async fn init_lease(client: Client, ns: &str, deployment_name: &str) -> Result<L
         .await
         .map_err(Into::into)
 }
+
+async fn api_resource_exists<T>(client: &Client) -> bool
+where
+    T: Resource,
+    T::DynamicType: Default,
+{
+    let dt = Default::default();
+    let resources = client
+        .list_api_group_resources(&T::api_version(&dt))
+        .await
+        .expect("Failed to list API group resources");
+    resources.resources.iter().any(|r| r.kind == T::kind(&dt))
+}