[FIXED JENKINS-12680] the onOffline method wasn't called for abrupt client termination

changelog.html

@@ -93,7 +93,10 @@ Upcoming changes</a>
   <li class=bug>
     Fixed a bug in LDAP default root DN inference.
     (<a href="https://issues.jenkins-ci.org/browse/JENKINS-8152">issue 8152</a>)
-  <li class=rfe>
+  <li class=bug>
+    <tt>ComputerListener.onOffline</tt> was not called when the client was terminated abruptly.
+    (<a href="https://issues.jenkins-ci.org/browse/JENKINS-12680">issue 12680</a>)
+  <li class=ref>
     CLI now supports also encrypted key file
   <li class=rfe>
     Recognize test results from eviware:maven-soapui-plugin.

core/src/main/java/hudson/slaves/SlaveComputer.java

@@ -329,14 +329,14 @@ public class SlaveComputer extends Computer {
         channel.addListener(new Channel.Listener() {
             @Override
             public void onClosed(Channel c, IOException cause) {
-                SlaveComputer.this.channel = null;
                 // Orderly shutdown will have null exception
                 if (cause!=null) {
                     offlineCause = new ChannelTermination(cause);
-                     cause.printStackTrace(taskListener.error("Connection terminated"));
+                    cause.printStackTrace(taskListener.error("Connection terminated"));
                 } else {
                     taskListener.getLogger().println("Connection terminated");
                 }
+                closeChannel();
                 launcher.afterDisconnect(SlaveComputer.this, taskListener);
             }
         });
@@ -501,9 +501,9 @@ public class SlaveComputer extends Computer {
             } catch (IOException e) {
                 logger.log(Level.SEVERE, "Failed to terminate channel to " + getDisplayName(), e);
             }
+            for (ComputerListener cl : ComputerListener.all())
+                cl.onOffline(this);
         }
-        for (ComputerListener cl : ComputerListener.all())
-            cl.onOffline(this);
     }
 
     @Override

test/src/test/java/hudson/slaves/JNLPLauncherTest.java

@@ -31,13 +31,17 @@ import hudson.model.Computer;
 import hudson.model.Node;
 import hudson.model.Node.Mode;
 import hudson.model.Slave;
+import hudson.model.TaskListener;
 import hudson.remoting.Callable;
 import hudson.remoting.Which;
 import hudson.util.ArgumentListBuilder;
 
 import org.jvnet.hudson.test.HudsonTestCase;
+import org.jvnet.hudson.test.TestExtension;
 
+import javax.inject.Inject;
 import java.io.File;
+import java.io.IOException;
 import java.net.URL;
 import java.util.ArrayList;
 import java.util.List;
@@ -69,8 +73,22 @@ public class JNLPLauncherTest extends HudsonTestCase {
     public void testHeadlessLaunch() throws Exception {
         Computer c = addTestSlave();
         launchJnlpAndVerify(c, buildJnlpArgs(c).add("-arg","-headless"));
+        // make sure that onOffline gets called just the right number of times
+        assertEquals(1, ComputerListener.all().get(ListenerImpl.class).offlined);
     }
 
+    @TestExtension
+    public static class ListenerImpl extends ComputerListener {
+        int offlined = 0;
+
+        @Override
+        public void onOffline(Computer c) {
+            offlined++;
+            assertTrue(c.isOffline());
+        }
+    }
+    
+    
     private ArgumentListBuilder buildJnlpArgs(Computer c) throws Exception {
         ArgumentListBuilder args = new ArgumentListBuilder();
         args.add(new File(new File(System.getProperty("java.home")),"bin/java").getPath(),"-jar");