From 19daf7790c5de45c7070216a70f917ecc7f6454b Mon Sep 17 00:00:00 2001
From: Thuan Vo <thuan.votann@gmail.com>
Date: Tue, 9 Apr 2024 15:49:40 -0700
Subject: [PATCH] fix(k8s): fix realm node not found and deletion constraint
 violation

---
 .../cryostat/discovery/KubeApiDiscovery.java  | 51 ++++++++++---------
 1 file changed, 28 insertions(+), 23 deletions(-)

diff --git a/src/main/java/io/cryostat/discovery/KubeApiDiscovery.java b/src/main/java/io/cryostat/discovery/KubeApiDiscovery.java
index 92e6695c3..e0827ab58 100644
--- a/src/main/java/io/cryostat/discovery/KubeApiDiscovery.java
+++ b/src/main/java/io/cryostat/discovery/KubeApiDiscovery.java
@@ -51,6 +51,7 @@
 import io.fabric8.kubernetes.client.informers.SharedIndexInformer;
 import io.quarkus.runtime.ShutdownEvent;
 import io.quarkus.runtime.StartupEvent;
+import jakarta.annotation.Priority;
 import jakarta.enterprise.context.ApplicationScoped;
 import jakarta.enterprise.event.Observes;
 import jakarta.inject.Inject;
@@ -113,7 +114,7 @@ protected HashMap<String, SharedIndexInformer<Endpoints>> initialize()
             };
 
     @Transactional
-    void onStart(@Observes StartupEvent evt) {
+    void onStart(@Observes @Priority(1) StartupEvent evt) {
         if (!(enabled())) {
             return;
         }
@@ -135,8 +136,14 @@ void onStart(@Observes StartupEvent evt) {
         }
 
         logger.infov("Starting {0} client", REALM);
+    }
 
-        safeGetInformers(); // trigger lazy init
+    void initializeInformers(@Observes StartupEvent evt) {
+        try {
+            nsInformers.get();
+        } catch (ConcurrentException e) {
+            throw new IllegalStateException(e);
+        }
     }
 
     void onStop(@Observes ShutdownEvent evt) {
@@ -165,16 +172,6 @@ KubernetesClient client() {
         return kubeConfig.kubeClient();
     }
 
-    private Map<String, SharedIndexInformer<Endpoints>> safeGetInformers() {
-        Map<String, SharedIndexInformer<Endpoints>> informers;
-        try {
-            informers = nsInformers.get();
-        } catch (ConcurrentException e) {
-            throw new IllegalStateException(e);
-        }
-        return informers;
-    }
-
     private boolean isCompatiblePort(EndpointPort port) {
         return JmxPortNames.orElse(List.of()).contains(port.getName())
                 || JmxPortNumbers.orElse(List.of()).contains(port.getPort());
@@ -236,18 +233,26 @@ private void pruneOwnerChain(DiscoveryNode nsNode, TargetTuple targetTuple) {
             Target target = Target.getTargetByConnectUrl(targetTuple.toTarget().connectUrl);
             DiscoveryNode targetNode = target.discoveryNode;
 
-            Pair<HasMetadata, DiscoveryNode> node = Pair.of(null, targetNode);
-            while (true) {
-                Pair<HasMetadata, DiscoveryNode> owner = getOwnerNode(node);
-                if (owner == null) {
-                    break;
-                }
-                DiscoveryNode ownerNode = owner.getRight();
-                if (node.getRight().children.isEmpty()) {
-                    ownerNode.children.remove(node.getRight());
-                    ownerNode.persist();
+            if (nsNode.children.contains(targetNode)) {
+                nsNode.children.remove(targetNode);
+            } else {
+                Pair<HasMetadata, DiscoveryNode> node =
+                        queryForNode(
+                                targetRef.getNamespace(), targetRef.getName(), targetRef.getKind());
+                node.getRight().children.remove(targetNode);
+                node.getRight().persist();
+                while (true) {
+                    Pair<HasMetadata, DiscoveryNode> owner = getOwnerNode(node);
+                    if (owner == null) {
+                        break;
+                    }
+                    DiscoveryNode ownerNode = owner.getRight();
+                    if (node.getRight().children.isEmpty()) {
+                        ownerNode.children.remove(node.getRight());
+                        ownerNode.persist();
+                    }
+                    node = owner;
                 }
-                node = owner;
             }
 
             target.delete();