Fix data loss in rmtree when deletion fails

app/utils/cli.py

@@ -2,34 +2,81 @@
 import shutil
 import stat
 import time
+from datetime import datetime
 from pathlib import Path
 from typing import Union
 
+from app.utils.click import error
+
 MAX_DELETE_RETRIES = 20
 MAX_RETRY_INTERVAL = 0.2
 
 
 def rmtree(folder_name: Union[str, Path]) -> None:
     """
-    Remove a directory tree.
-
-    Raises RuntimeError if the folder still exists after max retries.
+    Remove a directory tree with backup-and-restore safety mechanism.
+
+    If deletion fails, the folder is restored to its original state,
+    ensuring no data loss occurs.
+
+    Raises RuntimeError if the folder still exists after max retries,
+    or displays error message if deletion fails.
     """
     if not os.path.exists(folder_name):
         return
 
+    # Convert to absolute path for consistency
+    folder_path = os.path.abspath(folder_name)
+    folder_basename = os.path.basename(folder_path)
+    parent_dir = os.path.dirname(folder_path)
+
+    # Create backup name with timestamp
+    timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
+    backup_name = f".{folder_basename}_backup_{timestamp}"
+    backup_path = os.path.join(parent_dir, backup_name)
+
+    # Create backup
+    try:
+        shutil.copytree(folder_path, backup_path, symlinks=True, ignore_dangling_symlinks=True)
+    except Exception as backup_error:
+        error(
+            f"Failed to create backup of {folder_name}. Deletion aborted."
+        )
+
+    # Attempt deletion
     def force_remove_readonly(func, path, _):
         os.chmod(path, stat.S_IWRITE)
         func(path)
-
-    shutil.rmtree(folder_name, onerror=force_remove_readonly)
-
-    # Wait for folder to be fully deleted (Windows can be slow with permissions)
-    max_retries = MAX_DELETE_RETRIES
-    for _ in range(max_retries):
-        if not os.path.exists(folder_name):
-            return
-        time.sleep(MAX_RETRY_INTERVAL)
-
-    # If folder still exists after retries, raise error
-    raise RuntimeError(f"Failed to delete {folder_name} after {max_retries} retries")
+
+    try:
+        shutil.rmtree(folder_path, onerror=force_remove_readonly)
+
+        # Wait for folder to be fully deleted (Windows can be slow with permissions)
+        max_retries = MAX_DELETE_RETRIES
+        for _ in range(max_retries):
+            if not os.path.exists(folder_path):
+                break
+            time.sleep(MAX_RETRY_INTERVAL)
+
+        # If folder still exists after retries, raise error
+        if os.path.exists(folder_path):
+            raise RuntimeError(f"Failed to delete {folder_name} after {max_retries} retries")
+
+        # Deletion succeeded, clean up backup
+        shutil.rmtree(backup_path, ignore_errors=True)
+
+    except Exception as deletion_error:
+        try:
+            shutil.copytree(backup_path, folder_path, dirs_exist_ok=True)
+            shutil.rmtree(backup_path, ignore_errors=True)
+        except Exception as restoration_error:
+            # Restoration also failed - leave backup in place
+            error(
+                f"Failed to delete {folder_name}. Please make sure it is not accessed by other process. "
+                f"Your data is preserved at: {backup_path}"
+            )
+
+        # Restoration succeeded, show error message
+        error(
+            f"Failed to delete {folder_name}. Please make sure it is not accessed by other process."
+        )