From 66e538efbc67d76c450f5ae9b1b9c5e590378558 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Antonio=20Mu=C3=B1iz?= <amunizmartin@gmail.com>
Date: Mon, 16 Dec 2024 13:10:57 +0100
Subject: [PATCH] Moving informer registration to `KubernetesCloud` and make it
 thread safe.

---
 .../plugins/kubernetes/KubernetesCloud.java   | 33 ++++++++++++++++---
 .../kubernetes/KubernetesLauncher.java        | 21 ++----------
 2 files changed, 31 insertions(+), 23 deletions(-)

diff --git a/src/main/java/org/csanchez/jenkins/plugins/kubernetes/KubernetesCloud.java b/src/main/java/org/csanchez/jenkins/plugins/kubernetes/KubernetesCloud.java
index 21dab08eb..fec252971 100644
--- a/src/main/java/org/csanchez/jenkins/plugins/kubernetes/KubernetesCloud.java
+++ b/src/main/java/org/csanchez/jenkins/plugins/kubernetes/KubernetesCloud.java
@@ -2,6 +2,7 @@
 
 import static java.nio.charset.StandardCharsets.UTF_8;
 import static org.apache.commons.lang.StringUtils.isEmpty;
+import static org.csanchez.jenkins.plugins.kubernetes.PodTemplateUtils.sanitizeLabel;
 
 import com.cloudbees.plugins.credentials.CredentialsMatchers;
 import com.cloudbees.plugins.credentials.common.StandardCredentials;
@@ -51,11 +52,13 @@
 import java.util.Base64;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.TimeUnit;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import javax.servlet.ServletException;
@@ -72,6 +75,7 @@
 import org.csanchez.jenkins.plugins.kubernetes.pipeline.PodTemplateMap;
 import org.csanchez.jenkins.plugins.kubernetes.pod.retention.Default;
 import org.csanchez.jenkins.plugins.kubernetes.pod.retention.PodRetention;
+import org.csanchez.jenkins.plugins.kubernetes.watch.PodStatusEventHandler;
 import org.jenkinsci.plugins.kubernetes.auth.KubernetesAuth;
 import org.jenkinsci.plugins.kubernetes.auth.KubernetesAuthException;
 import org.jenkinsci.plugins.plaincredentials.impl.StringCredentialsImpl;
@@ -931,10 +935,6 @@ public HttpResponse doCreate(StaplerRequest req, StaplerResponse rsp)
         return FormApply.success("templates");
     }
 
-    public Map<String, SharedIndexInformer<Pod>> getInformers() {
-        return informers;
-    }
-
     @Extension
     public static class DescriptorImpl extends Descriptor<Cloud> {
         @Override
@@ -1320,6 +1320,31 @@ public Cloud reconfigure(@NonNull StaplerRequest req, JSONObject form) throws De
         return newInstance;
     }
 
+    public void registerPodInformer(KubernetesSlave node, KubernetesClient client, String namespace) {
+        if (informers.get(namespace) == null) {
+            synchronized (this) {
+                // sync recheck
+                if (informers.get(namespace) != null) {
+                    return;
+                }
+                Map<String, String> labelsFilter =
+                        new HashMap<>(node.getKubernetesCloud().getPodLabelsMap());
+                String jenkinsUrlLabel = sanitizeLabel(this.getJenkinsUrlOrNull());
+                if (jenkinsUrlLabel != null) {
+                    labelsFilter.put(PodTemplateBuilder.LABEL_KUBERNETES_CONTROLLER, jenkinsUrlLabel);
+                }
+                SharedIndexInformer<Pod> inform = client.pods()
+                        .inNamespace(namespace)
+                        .withLabels(labelsFilter)
+                        .inform(new PodStatusEventHandler(), TimeUnit.SECONDS.toMillis(30));
+                LOGGER.info(String.format(
+                        "Registered informer to watch pod events on namespace [%s], with labels [%s]",
+                        namespace, labelsFilter));
+                informers.put(namespace, inform);
+            }
+        }
+    }
+
     @Extension
     public static class PodTemplateSourceImpl extends PodTemplateSource {
         @NonNull
diff --git a/src/main/java/org/csanchez/jenkins/plugins/kubernetes/KubernetesLauncher.java b/src/main/java/org/csanchez/jenkins/plugins/kubernetes/KubernetesLauncher.java
index 5a1316a5f..8608ebdd4 100644
--- a/src/main/java/org/csanchez/jenkins/plugins/kubernetes/KubernetesLauncher.java
+++ b/src/main/java/org/csanchez/jenkins/plugins/kubernetes/KubernetesLauncher.java
@@ -149,25 +149,8 @@ public synchronized void launch(SlaveComputer computer, TaskListener listener) {
                     .orElse(null);
             node.setNamespace(namespace);
 
-            // register a namespace informer (if not registered yet) show relevant pod events in build logs
-            Map<String, SharedIndexInformer<Pod>> informers =
-                    node.getKubernetesCloud().getInformers();
-            if (informers.get(namespace) == null) {
-                Map<String, String> labelsFilter =
-                        new HashMap<>(node.getKubernetesCloud().getPodLabelsMap());
-                String jenkinsUrlLabel = sanitizeLabel(cloud.getJenkinsUrlOrNull());
-                if (jenkinsUrlLabel != null) {
-                    labelsFilter.put(PodTemplateBuilder.LABEL_KUBERNETES_CONTROLLER, jenkinsUrlLabel);
-                }
-                SharedIndexInformer<Pod> inform = client.pods()
-                        .inNamespace(namespace)
-                        .withLabels(labelsFilter)
-                        .inform(new PodStatusEventHandler(), TimeUnit.SECONDS.toMillis(30));
-                LOGGER.info(String.format(
-                        "Registered informer to watch pod events on namespace [%s], with labels [%s]",
-                        namespace, labelsFilter));
-                informers.put(namespace, inform);
-            }
+            // register a namespace informer (if not registered yet) to show relevant pod events in build logs
+            cloud.registerPodInformer(node, client, namespace);
 
             // if the controller was interrupted after creating the pod but before it connected back, then
             // the pod might already exist and the creating logic must be skipped.