Make a backup of the config directory on startup

On each start the config is backed up in a separate directory. 5 backups are kept, older backups get deleted.

CHANGELOG.md

@@ -5,6 +5,15 @@
   object from the persisted groups.json file. Now the model state is updated
   before performing the check.
 * Fixed: File handles not released for failed segments
+* Changed config backup mechanism: Instead of creating a backup of the config
+  in case of an error, ctbrec now creates a backup of the config on each start.
+  Up to 5 backups are kept, older backups will be deleted automatically
+  The backup will be created right next to the current config dir. E.g.:
+  ```
+  ctbrec
+    |- 4.7.13
+    |- 4.7.13_backup_2022-11-12_18-03-35_712
+  ```
 
 4.7.13
 ========================

common/src/main/java/ctbrec/Config.java

@@ -17,8 +17,6 @@ import org.slf4j.LoggerFactory;
 import java.io.File;
 import java.io.IOException;
 import java.nio.file.Files;
-import java.nio.file.StandardCopyOption;
-import java.text.SimpleDateFormat;
 import java.time.Instant;
 import java.time.LocalDateTime;
 import java.time.LocalTime;
@@ -61,6 +59,8 @@ public class Config {
             configDir = new File(OS.getConfigDir(), Version.getVersion().toString());
         }
 
+        backupConfig(configDir);
+
         if (System.getProperty("ctbrec.config") != null) {
             filename = System.getProperty("ctbrec.config");
         } else {
@@ -68,6 +68,30 @@ public class Config {
         }
     }
 
+    private void backupConfig(File currentConfigDir) throws IOException {
+        DateTimeFormatter dateTimeFormatter = DateTimeFormatter.ofPattern(RECORDING_DATE_FORMAT);
+        File src = currentConfigDir;
+        File target = new File(src.getParentFile(), src.getName() + "_backup_" + dateTimeFormatter.format(LocalDateTime.now()));
+        LOG.info("Creating a backup of the config in {}", target);
+        FileUtils.copyDirectory(src, target, pathname -> !(pathname.toString().contains("minimal-browser") && pathname.toString().contains("Cache")), true);
+        deleteOldBackups(currentConfigDir);
+    }
+
+    private void deleteOldBackups(File currentConfigDir) {
+        File parent = currentConfigDir.getParentFile();
+        File[] backupDirectories = parent.listFiles(file -> file.isDirectory() && file.getName().matches(".*?_backup_\\d{4}-\\d{2}-\\d{2}_\\d{2}-\\d{2}-\\d{2}_\\d{3}"));
+        Arrays.sort(backupDirectories, Comparator.comparing(File::getName));
+        for (int i = 0; i < backupDirectories.length - 5; i++) {
+            File dirToDelete = backupDirectories[i];
+            try {
+                LOG.info("Delete old config backup {}", dirToDelete);
+                IoUtils.deleteDirectory(dirToDelete);
+            } catch (IOException e) {
+                LOG.error("Couldn't delete old config backup {}. You might have to delete it manually.", dirToDelete, e);
+            }
+        }
+    }
+
     private void copyConfigIfNewVersion() throws IOException {
         File configDirectory;
         if (System.getProperty(SYSPROP_CONFIG_DIR) != null) {
@@ -146,7 +170,6 @@ public class Config {
                 for (Site site : sites) {
                     site.setEnabled(!settings.disabledSites.contains(site.getName()));
                 }
-                makeBackup(configFile);
                 throw e;
             }
         } else {
@@ -238,23 +261,11 @@ public class Config {
         if (settings.modelsIgnored != null && !settings.modelsIgnored.isEmpty()) {
             settings.ignoredModels = settings.modelsIgnored.stream()
                     .map(Model::getUrl)
-                    .collect(Collectors.toList());
+                    .collect(Collectors.toList()); // NOSONAR modifiable list desired here
             settings.modelsIgnored = null;
         }
     }
 
-    private void makeBackup(File source) {
-        try {
-            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd_HH-mm-ss");
-            String timestamp = sdf.format(new Date());
-            String backup = source.getName() + '.' + timestamp;
-            File target = new File(source.getParentFile(), backup);
-            Files.copy(source.toPath(), target.toPath(), StandardCopyOption.REPLACE_EXISTING);
-        } catch (Exception e) {
-            LOG.error("Couldn't create backup of settings file", e);
-        }
-    }
-
     public static synchronized void init(List<Site> sites) throws IOException {
         if (instance == null) {
             instance = new Config(sites);