[JBEAP-27367] Improve logging when performing rollback

prospero-cli/src/main/java/org/wildfly/prospero/cli/CliMessages.java

@@ -626,4 +626,12 @@ default String featurePackDoesNotSupportCustomization(String featurePackName) {
     default String featurePackRequiresLicense(String featurePackName) {
         return format(bundle.getString("prospero.features.add.required_licences"), featurePackName);
     }
+
+    default String candidateApplyRollbackSuccess() {
+        return bundle.getString("prospero.candidate.apply.error.rolled_back.desc");
+    }
+
+    default String candidateApplyRollbackFailure(Path backup) {
+        return format(bundle.getString("prospero.candidate.apply.error.rollback_error.desc"), backup);
+    }
 }

prospero-cli/src/main/java/org/wildfly/prospero/cli/ExecutionExceptionHandler.java

@@ -24,6 +24,7 @@
 import org.wildfly.channel.ChannelMetadataCoordinate;
 import org.wildfly.channel.Repository;
 import org.wildfly.prospero.api.ArtifactUtils;
+import org.wildfly.prospero.api.exceptions.ApplyCandidateException;
 import org.wildfly.prospero.api.exceptions.ArtifactResolutionException;
 import org.wildfly.prospero.api.exceptions.ChannelDefinitionException;
 import org.wildfly.prospero.api.exceptions.MetadataException;
@@ -104,6 +105,16 @@ public int handleExecutionException(Exception ex, CommandLine commandLine, Comma
                 if (ex.getCause() != null && (ex.getCause() instanceof MarkedYAMLException || ex.getCause() instanceof JsonMappingException)) {
                     console.error(ex.getCause().getLocalizedMessage());
                 }
+            } else if (ex instanceof ApplyCandidateException) {
+                ApplyCandidateException ace = (ApplyCandidateException) ex;
+                console.error(System.lineSeparator() + ace.getMessage());
+
+                if (ace.isRollbackSuccessful()) {
+                    console.error(System.lineSeparator() + CliMessages.MESSAGES.candidateApplyRollbackSuccess());
+                } else {
+                    console.error(System.lineSeparator() + CliMessages.MESSAGES.candidateApplyRollbackFailure(ace.getBackupPath()));
+                }
+
             } else {
                 console.error(CliMessages.MESSAGES.errorHeader(ex.getLocalizedMessage()));
             }

prospero-cli/src/main/resources/UsageMessages.properties

@@ -369,3 +369,6 @@ prospero.changes.diff.channel=channel
 prospero.changes.diff.features_changes=Installed features changes
 
 prospero.changes.conflict.header=Conflicting changes detected in the update:
+
+prospero.candidate.apply.error.rolled_back.desc=The incomplete update changes have been rolled back. Please resolve above error and try to perform update again.
+prospero.candidate.apply.error.rollback_error.desc=Unable to restore the incomplete update changes. The server might have been left in a corrupted state, please check the backup of the server at %s.

prospero-common/src/main/java/org/wildfly/prospero/ProsperoLogger.java

@@ -384,4 +384,7 @@ default IllegalArgumentException invalidInstallationDir(Path path, List<Path> mi
 
     @Message(id = 271, value = "Unable to evaluate symbolic link %s.")
     RuntimeException unableToEvaluateSymbolicLink(Path symlink, @Cause IOException e);
+
+    @Message(id = 272, value = "Failed to apply the candidate changes due to: %s")
+    String failedToApplyCandidate(String reason);
 }

prospero-common/src/main/java/org/wildfly/prospero/actions/ApplyCandidateAction.java

@@ -48,6 +48,7 @@
 import org.wildfly.prospero.api.InstallationMetadata;
 import org.wildfly.prospero.api.MavenOptions;
 import org.wildfly.prospero.api.SavedState;
+import org.wildfly.prospero.api.exceptions.ApplyCandidateException;
 import org.wildfly.prospero.api.exceptions.InvalidUpdateCandidateException;
 import org.wildfly.prospero.api.exceptions.MetadataException;
 import org.wildfly.prospero.api.exceptions.OperationException;
@@ -205,16 +206,20 @@ public List<FileConflict> applyUpdate(Type operation) throws ProvisioningExcepti
             backup.close();
             return conflicts;
         } catch (IOException ex) {
+            boolean backupRestored = false;
             try {
                 if (backup != null) {
                     backup.restore();
                     // remove close the backup if the restore was successful. If there were any errors, we want to keep the backup untouched.
                     backup.close();
+                    backupRestored = true;
                 }
             } catch (IOException e) {
                 ProsperoLogger.ROOT_LOGGER.error("Unable to restore the server from a backup, preserving the backup.", e);
             }
-            throw new ProvisioningException("Unable to apply the candidate changes.", ex);
+            final String msg = ex.getLocalizedMessage() == null ? ex.getMessage() : ex.getLocalizedMessage();
+            throw new ApplyCandidateException(ProsperoLogger.ROOT_LOGGER.failedToApplyCandidate(msg),
+                    backupRestored, installationDir.resolve(ApplyStageBackup.BACKUP_FOLDER), ex);
         }
     }
 

prospero-common/src/main/java/org/wildfly/prospero/api/exceptions/ApplyCandidateException.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2024 Red Hat, Inc. and/or its affiliates
+ * and other contributors as indicated by the @author tags.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.wildfly.prospero.api.exceptions;
+
+import java.nio.file.Path;
+
+public class ApplyCandidateException extends OperationException {
+
+    private final boolean rollbackSuccessful;
+    private final Path backupPath;
+
+    public ApplyCandidateException(String msg, boolean rollbackSuccessful, Path backupPath, Throwable e) {
+        super(msg, e);
+        this.rollbackSuccessful = rollbackSuccessful;
+        this.backupPath = backupPath;
+    }
+
+    public boolean isRollbackSuccessful() {
+        return rollbackSuccessful;
+    }
+
+    public Path getBackupPath() {
+        return backupPath;
+    }
+}