[JENKINS-67679] add maintenance mode to pause provisioning nodes

src/main/java/org/csanchez/jenkins/plugins/kubernetes/KubernetesCloud.java

@@ -131,7 +131,7 @@ public class KubernetesCloud extends Cloud {
 
     // Integer to differentiate null from 0
     private Integer waitForPodSec = DEFAULT_WAIT_FOR_POD_SEC;
-
+    private boolean maintenanceMode;
     @CheckForNull
     private PodRetention podRetention = PodRetention.getKubernetesCloudDefault();
 
@@ -499,6 +499,14 @@ public void setPodRetention(PodRetention podRetention) {
         this.podRetention = podRetention;
     }
 
+    public boolean isMaintenanceMode() {
+        return maintenanceMode;
+    }
+    @DataBoundSetter
+    public void setMaintenanceMode(boolean maintenanceMode) {
+        this.maintenanceMode = maintenanceMode;
+    }
+
     /**
      * Connects to Kubernetes.
      *
@@ -563,6 +571,10 @@ public Collection<NodeProvisioner.PlannedNode> provision(@NonNull final Cloud.Cl
 
     @Override
     public boolean canProvision(@NonNull Cloud.CloudState state) {
+        if (isMaintenanceMode()){
+            LOGGER.log(Level.FINE, "skip provision because maintenanceMode is set");
+            return false;
+        }
         return getTemplate(state.getLabel()) != null;
     }
 

src/main/resources/org/csanchez/jenkins/plugins/kubernetes/KubernetesCloud/config.jelly

@@ -78,7 +78,9 @@
       <f:entry title="Seconds to wait for pod to be running" field="waitForPodSec">
         <f:number clazz="required number" min="0" step="1" default="${descriptor.defaultWaitForPod}"/>
       </f:entry>
-
+      <f:entry title="${%Maintenance Mode}" field="maintenanceMode">
+        <f:checkbox default="false" />
+      </f:entry>
       <f:advanced>
         <f:entry title="${%Container Cleanup Timeout (minutes)}" field="retentionTimeout">
             <f:number min="${descriptor.defaultRetentionTimeout}" default="${descriptor.defaultRetentionTimeout}" checkMethod="post"/>

src/main/resources/org/csanchez/jenkins/plugins/kubernetes/KubernetesCloud/config_zh_CN.properties

@@ -42,3 +42,4 @@ Images=\u955C\u50CF
 List\ of\ Images\ to\ be\ launched\ as\ agents=\u4F5C\u4E3A\u4EE3\u7406\u542F\u52A8\u7684\u955C\u50CF\u5217\u8868
 Delete\ Template=\u5220\u9664\u6A21\u677F
 Add\ Pod\ Template=\u6DFB\u52A0 Pod \u6A21\u677F
+Maintenance\ Mode=\u00e7\u00bb\u00b4\u00e6\u0160\u00a4\u00e6\u00a8\u00a1\u00e5\u00bc\ufffd

src/main/resources/org/csanchez/jenkins/plugins/kubernetes/KubernetesCloud/help-maintenanceMode.html

@@ -0,0 +1,3 @@
+<div>
+    Stop provisioning pods until maintenance is completed
+</div>

src/test/java/org/csanchez/jenkins/plugins/kubernetes/KubernetesCloudTest.java

@@ -1,9 +1,5 @@
 package org.csanchez.jenkins.plugins.kubernetes;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNull;
-import static org.junit.Assert.fail;
-
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -21,6 +17,8 @@
 import com.gargoylesoftware.htmlunit.html.HtmlFormUtil;
 import com.gargoylesoftware.htmlunit.html.HtmlInput;
 import com.gargoylesoftware.htmlunit.html.HtmlPage;
+import hudson.model.Label;
+import hudson.slaves.Cloud;
 import org.apache.commons.beanutils.PropertyUtils;
 import org.apache.commons.lang3.RandomStringUtils;
 import org.apache.commons.lang3.RandomUtils;
@@ -38,6 +36,8 @@
 
 import jenkins.model.JenkinsLocationConfiguration;
 
+import static org.junit.Assert.*;
+
 public class KubernetesCloudTest {
 
     @Rule
@@ -297,6 +297,20 @@ public void readResolveContainerCapZero() {
         assertEquals(cloud.getContainerCap(), Integer.MAX_VALUE);
     }
 
+    @Test
+    public void maintenanceModeNoProvision() throws Exception {
+        String testNodeLabel = "test-node";
+        PodTemplate podTemplate = new PodTemplate("test");
+        podTemplate.setLabel(testNodeLabel);
+        KubernetesCloud cloud = new KubernetesCloud("kubernetes");
+        cloud.addTemplate(podTemplate);
+        Cloud.CloudState state = new Cloud.CloudState(Label.parseExpression(testNodeLabel), 1);
+        assertTrue(cloud.canProvision(state));
+        // disable provision
+        cloud.setMaintenanceMode(true);
+        assertFalse(cloud.canProvision(state));
+    }
+
     public HtmlInput getInputByName(DomElement root, String name) {
         DomNodeList<HtmlElement> inputs = root.getElementsByTagName("input");
         for (HtmlElement input : inputs) {