Fixed many bugs, added CLI progress bar and completed backup method

backup.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
 # backup.py: modular and lightweight backup utility
-# Developed by Marco Cetica (c) 2018, 2023, 2024, 2026
+# Developed by Marco Cetica (c) 2018-2026
 #
 
 import argparse
@@ -18,7 +18,6 @@ from dataclasses import dataclass
 from typing import Generic, TypeVar, Union, Literal, List
 
 T = TypeVar("T")
-
 @dataclass(frozen=True)
 class Ok(Generic[T]):
     """Sum type to represent results"""
@@ -49,20 +48,25 @@ class BackupState:
 
 class BackupProgress:
     """Progress indicator for backup operations"""
-    def __init__(self, total: int, operation: str):
+    def __init__(self, total: int, operation: str) -> None:
         self.total = total
         self.current = 0
         self.operation = operation
 
-    def update(self, message: str = ""):
-        """Update progress"""
+    def draw_progress_bar(self, message: str = "") -> None:
+        """draw progress bar"""
         self.current += 1
         percentage = (self.current / self.total) * 100 if self.total > 0 else 0
 
-        status = f"\r{self.operation}: [{self.current}/{self.total}] {percentage: .1f}% - {message}"
+        # Create a CLI prograss bar
+        bar_width = 30
+        filled = int(bar_width * self.current / self.total)
+        bar = '█' * filled + '░' * (bar_width - filled)
+
+        status = f"\r :: {self.operation} [{bar}] {percentage:.1f}% ({self.current}/{self.total}) - (processing '{message}') ::"
         print(f"\r\033[K{status}", end='', flush=True)
 
-    def finish(self):
+    def finish(self) -> None:
         """Print new line"""
         print()
 
@@ -111,7 +115,7 @@ class Backup:
                         continue
 
                     if '=' not in line:
-                        print(f"Warning: invalid format at line {pos}: {line}")
+                        return Err(f"invalid format at line {pos}: '{line}'")
 
                     label, path_str = line.split('=', 1)
                     path = Path(path_str.strip())
@@ -141,7 +145,7 @@ class Backup:
                 return True
 
             # Skip named pipes (FIFOs)
-            if path.stat().st_mode & 0o170000 == 0o010000:
+            if (path.stat().st_mode & 0o170000) == 0o010000:
                 return True
 
             return False
@@ -163,7 +167,7 @@ class Backup:
         return ignored_files
 
     @staticmethod
-    def copy_files(source: Path, destination: Path, verbose: bool) -> Result[None]:
+    def copy_files(source: Path, destination: Path) -> Result[None]:
         """Copy files and directories preserving their metadata"""
         try:
             # Handle single file
@@ -171,9 +175,6 @@ class Backup:
                 # Parent directory might not exists, so we try to create it first
                 destination.parent.mkdir(parents=True, exist_ok=True)
 
-                if verbose:
-                    print(f"Copying file {source} -> {destination}")
-
                 # Copy file and its metadata
                 shutil.copy2(source, destination)
 
@@ -186,9 +187,6 @@ class Backup:
                 if destination.exists():
                     shutil.rmtree(destination)
 
-                if verbose:
-                    print(f"Copying directory {source} -> {destination}")
-
                 # Copy directory and its metadata.
                 # We also ignore special files and we preserves links instead
                 # of following them.
@@ -234,10 +232,11 @@ class Backup:
     def compute_file_hash(file_path: Path) -> Result[str]:
         """Compute SHA256 hash of a given file"""
         try:
+            hash_obj = hashlib.sha256()
             with open(file_path, "rb") as f:
                 for byte_block in iter(lambda: f.read(4096), b""):
-                    hashlib.sha256().update(byte_block)
-            return Ok(hashlib.sha256().hexdigest())
+                    hash_obj.update(byte_block)
+            return Ok(hash_obj.hexdigest())
         except IOError as e:
             return Err(f"Failed to read file {file_path}: {e}")
 
@@ -245,7 +244,7 @@ class Backup:
     def create_tarball(source_dir: Path, output_file: Path, verbose: bool) -> Result[None]:
         """Create a compressed tar archive of the backup directory"""
         if verbose:
-            print("Compressing backup...")
+            print("> Compressing backup...")
 
         cmd = [
             "tar",
@@ -256,14 +255,14 @@ class Backup:
             source_dir.name
         ]
 
-        if verbose:
-            cmd[1] += "-v"
+        # if verbose:
+        #     cmd.insert(1, "-v")
 
         # capture here means suppress it/holding it
-        result = subprocess.run(cmd, capture_output=not verbose, text=None)
+        result = subprocess.run(cmd, capture_output=not verbose, text=True)
 
         if result.returncode != 0:
-            error_msg = f"tar failed: {result.stderr if result.stderr else 'Unknown error code'}"
+            error_msg = f"tar failed: {result.stderr if result.stderr else 'unknown error code'}"
 
             return Err(error_msg)
 
@@ -272,8 +271,12 @@ class Backup:
     @staticmethod
     def encrypt_file(input_file: Path, output_file: Path, password: str, verbose: bool) -> Result[None]:
         """Encrypt a file with GPG in symmetric mode (using AES256)"""
+
+        if output_file.exists():
+            return Err("Encryption failed: archive already exists")
+        
         if verbose:
-            print("Encrypting backup...")
+            print("> Encrypting backup...", end='', flush=True)
 
         cmd = [
             "gpg", "-a",
@@ -296,6 +299,7 @@ class Backup:
         if result.returncode != 0:
             return Err(f"Encryption failed: {result.stderr.decode()}")
 
+        print("DONE")
         return Ok(None)
 
     def make_backup(self, config: BackupState) -> Result[None]:
@@ -321,7 +325,7 @@ class Backup:
         # Backup each source
         sources_count = len(config.sources)
         for idx, source in enumerate(config.sources, 1):
-            print(f"Copying {source.label} ({idx}/{sources_count})")
+            print(f"> Copying {source.label} ({idx}/{sources_count})")
 
             # Create source subdirectory
             source_dir = work_dir / f"backup-{source.label}-{date_str}"
@@ -329,7 +333,7 @@ class Backup:
                 source_dir.mkdir(parents=True, exist_ok=True)
 
             # Copy files
-            copy_res = self.copy_files(source.path, work_dir, config.verbose)
+            copy_res = self.copy_files(source.path, source_dir)
             match copy_res:
                 case Err():
                     self.cleanup_files(work_dir, temp_tarball)
@@ -343,23 +347,21 @@ class Backup:
                 backup_progress: BackupProgress | None = None
 
                 if config.verbose:
-                    backup_progress = BackupProgress(len(files), "Computing checksums")
+                    backup_progress = BackupProgress(len(files), "Computing checksum")
 
-                checksum_fd = open(checksum_file, 'a')
-                for file in files:
-                    hash_result = self.compute_file_hash(file)
-                    match hash_result:
-                        case Err():
-                            checksum_fd.close()
-                            self.cleanup_files(work_dir, temp_tarball)
-                            return hash_result
-                        case Ok(value=v):
-                            checksum_fd.write(f"{v}\n")
+                with open(checksum_file, 'a') as checksum_fd:
+                    for file in files:
+                        hash_result = self.compute_file_hash(file)
+                        match hash_result:
+                            case Err():
+                                checksum_fd.close()
+                                self.cleanup_files(work_dir, temp_tarball)
+                                return hash_result
+                            case Ok(value=v):
+                                checksum_fd.write(f"{v}\n")
 
-                    if config.verbose and backup_progress is not None:
-                        backup_progress.update(str(file.name))
-
-                checksum_fd.close()
+                        if config.verbose and backup_progress is not None:
+                            backup_progress.draw_progress_bar(str(file.name))
 
                 if config.verbose and backup_progress is not None:
                     backup_progress.finish()
@@ -390,9 +392,8 @@ class Backup:
         elapsed_time = time.time() - start_time
         file_size = backup_archive.stat().st_size
         file_size_hr = Backup.prettify_size(file_size)
-
-        print(f"\nBackup complete")
-        print(f"File name: {backup_archive}")
+        
+        print(f"File name: '{backup_archive}'")
         if config.checksum:
             print(f"Checksum file: {checksum_file}")
         print(f"File size: {file_size} bytes ({file_size_hr})")
@@ -402,22 +403,7 @@ class Backup:
     
 def main():
     parser = argparse.ArgumentParser(
-        description="backup.py - modular and lightweight backup utility",
-        formatter_class=argparse.RawDescriptionHelpFormatter,
-        epilog="""
-Usage:
-  > Create a backup
-  sudo ./backup.py --backup sources.bk /home/user $PASS
-
-  > Create backup with checksum
-  sudo ./backup.py --checksum --backup sources.bk /home/user $PASS
-
-  > Extract and verify checksum
-  ./backup.py --checksum --extract backup.tar.gz.enc $PASS hashes.sha256
-
-  For more information visit: https://git.marcocetica.com/marco/backup.py
-  or issue `man backup.py` on your terminal.
-        """
+        description="backup.py - modular and lightweight backup utility"
     )
 
     parser.add_argument(
@@ -448,10 +434,15 @@ Usage:
 
     args = parser.parse_args()
 
+    if not (args.backup or args.extract):
+        parser.error("specify either --backup or --extract")
+
     # Check whether dependencies are installed
     deps_res = Backup.check_deps()
     match deps_res:
-        case Err(error=e): print(f"Error: {e}", file=sys.stderr)
+        case Err(error=e):
+            print(f"{e}", file=sys.stderr)
+            sys.exit(1)
         case Ok(): pass
 
     backup = Backup()
@@ -471,7 +462,7 @@ Usage:
         config: BackupState
         match sources_res:
             case Err(error=e):
-                print(f"Error: {e}", file=sys.stderr)
+                print(f"{e}", file=sys.stderr)
                 sys.exit(1)
             case Ok(value=v):
                 # Create a backup state
@@ -482,7 +473,12 @@ Usage:
                     checksum=args.checksum,
                     verbose=args.verbose
                 )
-        
+
+        backup_res = backup.make_backup(config)
+        match backup_res:
+            case Err(error=e):
+                print(f"{e}", file=sys.stderr)
+                sys.exit(1)
 
 if __name__ == "__main__":
     main()