Remove node configuration from Manage Jenkins' System page (#11224)

Co-authored-by: Tim Jacomb <21194782+timja@users.noreply.github.com>
Co-authored-by: Tim Jacomb <timjacomb1@gmail.com>

Author: janfaracik

core/src/main/java/jenkins/model/Jenkins.java

@@ -41,6 +41,7 @@
 import static java.util.logging.Level.INFO;
 import static java.util.logging.Level.SEVERE;
 import static java.util.logging.Level.WARNING;
+import static jenkins.model.Messages.Hudson_Computer_IncorrectNumberOfExecutors;
 
 import com.google.common.annotations.VisibleForTesting;
 import com.google.inject.Inject;
@@ -4100,28 +4101,6 @@ private boolean configureDescriptor(StaplerRequest2 req, JSONObject json, Descri
         return d.configure(req, js);
     }
 
-    /**
-     * Accepts submission from the node configuration page.
-     */
-    @POST
-    public synchronized void doConfigExecutorsSubmit(StaplerRequest2 req, StaplerResponse2 rsp) throws IOException, ServletException, FormException {
-        checkPermission(ADMINISTER);
-
-        try (BulkChange bc = new BulkChange(this)) {
-            JSONObject json = req.getSubmittedForm();
-
-            ExtensionList.lookupSingleton(MasterBuildConfiguration.class).configure(req, json);
-
-            getNodeProperties().rebuild(req, json.optJSONObject("nodeProperties"), NodeProperty.all());
-
-            bc.commit();
-        }
-
-        updateComputers(this);
-
-        FormApply.success(req.getContextPath() + '/' + toComputer().getUrl()).generateResponse(req, rsp, null);
-    }
-
     /**
      * Accepts the new description.
      */
@@ -5508,7 +5487,44 @@ public HttpResponse doDoDelete() throws IOException {
         @Override
         @POST
         public void doConfigSubmit(StaplerRequest2 req, StaplerResponse2 rsp) throws IOException, ServletException, FormException {
-            Jenkins.get().doConfigExecutorsSubmit(req, rsp);
+            checkPermission(ADMINISTER);
+
+            Jenkins jenkins = Jenkins.get();
+
+            try (BulkChange bc = new BulkChange(jenkins)) {
+                JSONObject json = req.getSubmittedForm();
+
+                try {
+                    // For compatibility reasons, this value is stored in Jenkins
+                    String num = json.getString("numExecutors");
+                    if (!num.matches("\\d+")) {
+                        throw new Descriptor.FormException(Hudson_Computer_IncorrectNumberOfExecutors(), "numExecutors");
+                    }
+
+                    jenkins.setNumExecutors(json.getInt("numExecutors"));
+                    if (req.hasParameter("builtin.mode")) {
+                        jenkins.setMode(Mode.valueOf(req.getParameter("builtin.mode")));
+                    } else {
+                        jenkins.setMode(Mode.NORMAL);
+                    }
+
+                    jenkins.setLabelString(json.optString("labelString", ""));
+                } catch (IOException e) {
+                    throw new Descriptor.FormException(e, "numExecutors");
+                }
+
+                jenkins.getNodeProperties().rebuild(req, json.optJSONObject("nodeProperties"), NodeProperty.all());
+
+                bc.commit();
+            }
+
+            jenkins.updateComputers(jenkins);
+
+            Computer computer = jenkins.toComputer();
+            if (computer == null) {
+                throw new IllegalStateException("Cannot find the computer object for the controller node");
+            }
+            FormApply.success(req.getContextPath() + '/' + computer.getUrl()).generateResponse(req, rsp, null);
         }
 
         @WebMethod(name = "config.xml")

core/src/main/java/jenkins/model/MasterBuildConfiguration.java

@@ -51,6 +51,12 @@ THE SOFTWARE.
                     codemirror-mode="${app.markupFormatter.codeMirrorMode}" codemirror-config="${app.markupFormatter.codeMirrorConfig}" previewEndpoint="/markupFormatter/previewDescription"/>
       </f:entry>
 
+      <!-- TODO remove after January 2026 LTS line -->
+      <div class="jenkins-alert jenkins-alert-info">
+        <l:icon src="symbol-computer" class="icon-sm jenkins-!-margin-right-1" />
+        ${%nodeHasBeenMoved(rootURL + '/manage/computer/(built-in)/configure')}
+      </div>
+
       <!-- global configuration from everyone -->
       <j:set var="editable" value="${h.getSortedDescriptorsForGlobalConfigUnclassified()}"/>
       <j:forEach var="descriptor" items="${h.getSortedDescriptorsForGlobalConfigUnclassifiedReadable()}">

core/src/main/resources/jenkins/model/Jenkins/configure.jelly

@@ -1 +1 @@
-LOADING=Loading
+nodeHasBeenMoved=Built-In Node is now configured in <a href="{0}">Nodes</a>.