NMS-20107: versioned group management API and PrimeVue Manage Groups page

opennms-config/src/main/java/org/opennms/netmgt/config/GroupManager.java

@@ -475,15 +475,25 @@ public void deleteRole(String name) throws Exception {
      */
     public synchronized void renameGroup(String oldName, String newName) throws Exception {
     	if (oldName != null && !oldName.equals("")) {
-    		if (m_groups.containsKey(oldName)) {
-    			Group grp = m_groups.remove(oldName);
-    			grp.setName(newName);
-    			m_groups.put(newName, grp);
-    		} else {
+    		if (!m_groups.containsKey(oldName)) {
     			throw new Exception("GroupFactory.renameGroup: Group doesn't exist: " + oldName);
     		}
-    		// Save into groups.xml
-    		saveGroups();
+    		Group grp = m_groups.remove(oldName);
+    		grp.setName(newName);
+    		m_groups.put(newName, grp);
+    		try {
+    			// Save into groups.xml
+    			saveGroups();
+    		} catch (final Exception e) {
+    			// The save did not persist, so undo the in-memory rename: the map
+    			// must keep reflecting groups.xml. Callers key referential-integrity
+    			// decisions (and their rollback) on hasGroup(), which must not report
+    			// a rename the file never received.
+    			m_groups.remove(newName);
+    			grp.setName(oldName);
+    			m_groups.put(oldName, grp);
+    			throw e;
+    		}
     	}
     }
 

opennms-config/src/test/java/org/opennms/netmgt/config/GroupManagerRenameTest.java

@@ -0,0 +1,100 @@
+/*******************************************************************************
+ * This file is part of OpenNMS(R).
+ *
+ * Copyright (C) 2026 The OpenNMS Group, Inc.
+ * OpenNMS(R) is Copyright (C) 1999-2026 The OpenNMS Group, Inc.
+ *
+ * OpenNMS(R) is a registered trademark of The OpenNMS Group, Inc.
+ *
+ * OpenNMS(R) is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License,
+ * or (at your option) any later version.
+ *
+ * OpenNMS(R) is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with OpenNMS(R).  If not, see:
+ *      http://www.gnu.org/licenses/
+ *
+ * For more information contact:
+ *     OpenNMS(R) Licensing <license@opennms.org>
+ *     http://www.opennms.org/
+ *     http://www.opennms.com/
+ *******************************************************************************/
+
+package org.opennms.netmgt.config;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+
+import org.junit.Test;
+
+public class GroupManagerRenameTest {
+
+    private static final String GROUPS_XML =
+            "<groupinfo xmlns=\"http://xmlns.opennms.org/xsd/groups\">\n"
+            + "  <header><rev>1.0</rev><created>now</created><mstation>test</mstation></header>\n"
+            + "  <groups>\n"
+            + "    <group><name>oldgroup</name><comments>c</comments><user>admin</user></group>\n"
+            + "  </groups>\n"
+            + "</groupinfo>";
+
+    /** A GroupManager with no file backing whose save can be flipped to fail. */
+    private static final class TestGroupManager extends GroupManager {
+        private boolean m_failSave = false;
+
+        TestGroupManager(final String xml) throws IOException {
+            parseXml(new ByteArrayInputStream(xml.getBytes(StandardCharsets.UTF_8)));
+        }
+
+        void failNextSave() {
+            m_failSave = true;
+        }
+
+        @Override
+        public void update() {
+            // nothing on disk to reconcile against
+        }
+
+        @Override
+        protected void saveXml(final String data) throws IOException {
+            if (m_failSave) {
+                throw new IOException("simulated save failure");
+            }
+        }
+    }
+
+    @Test
+    public void renameRollsBackWhenSaveFails() throws Exception {
+        final TestGroupManager gm = new TestGroupManager(GROUPS_XML);
+        gm.failNextSave();
+        try {
+            gm.renameGroup("oldgroup", "newgroup");
+            fail("the save failure should have propagated");
+        } catch (final IOException expected) {
+            // the in-memory map must keep reflecting groups.xml, not a phantom rename
+        }
+        assertTrue("the old group must survive a failed save", gm.hasGroup("oldgroup"));
+        assertFalse("a failed save must not leave a phantom renamed group", gm.hasGroup("newgroup"));
+        assertEquals("oldgroup", gm.getGroup("oldgroup").getName());
+    }
+
+    @Test
+    public void renameCommitsWhenSaveSucceeds() throws Exception {
+        final TestGroupManager gm = new TestGroupManager(GROUPS_XML);
+        gm.renameGroup("oldgroup", "newgroup");
+        assertTrue(gm.hasGroup("newgroup"));
+        assertFalse(gm.hasGroup("oldgroup"));
+        assertEquals("newgroup", gm.getGroup("newgroup").getName());
+    }
+}