[JENKINS-72159] deactivate MarkedOffline monitor when agents are online

core/src/main/java/hudson/node_monitors/NodeMonitorUpdater.java

@@ -1,6 +1,7 @@
 package hudson.node_monitors;
 
 import hudson.Extension;
+import hudson.model.AdministrativeMonitor;
 import hudson.model.Computer;
 import hudson.model.ComputerSet;
 import hudson.model.TaskListener;
@@ -9,6 +10,7 @@
 import java.io.IOException;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
+import jenkins.model.Jenkins;
 import jenkins.util.Timer;
 
 /**
@@ -28,6 +30,23 @@ public void run() {
         }
     };
 
+    private static final Runnable MARKEDOFFLINE_UPDATER = new Runnable() {
+        @Override
+        public void run() {
+            MonitorMarkedNodeOffline no = AdministrativeMonitor.all().get(MonitorMarkedNodeOffline.class);
+            if (no != null) {
+                boolean markedOffline = false;
+                for (Computer c : Jenkins.get().getComputers()) {
+                    if (c.getChannel() != null && c.getOfflineCause() instanceof MonitorOfflineCause) {
+                        markedOffline = true;
+                        break;
+                    }
+                }
+                no.active = markedOffline;
+            }
+        }
+    };
+
     private Future<?> future = Futures.precomputed(null);
 
     /**
@@ -41,4 +60,12 @@ public void onOnline(Computer c, TaskListener listener) throws IOException, Inte
             future = Timer.get().schedule(MONITOR_UPDATER, 5, TimeUnit.SECONDS);
         }
     }
+
+    @Override
+    public void onTemporarilyOnline(Computer c) {
+        synchronized (this) {
+            future.cancel(false);
+            future = Timer.get().schedule(MARKEDOFFLINE_UPDATER, 5, TimeUnit.SECONDS);
+        }
+    }
 }