Add helper class to manage Borg version and supported features. (#250)

* Add helper class to manage Borg version and supported features. Fixes #205

* Add setuptools as dependency to ensure pkg_resources is available.

* Review fixes, check for ZStd support, refactor some relative imports.

* Repo-add dialog: Disable Blake2 options if not available.

* When disabling compression algos, select by value, not index.

setup.cfg

@@ -39,6 +39,7 @@ install_requires =
   apscheduler
   psutil
   qdarkstyle
+  setuptools
   secretstorage; sys_platform != 'darwin'
   pyobjc-core; sys_platform == 'darwin'
   pyobjc-framework-Cocoa; sys_platform == 'darwin'

src/vorta/application.py

@@ -10,7 +10,7 @@ from .models import BackupProfileModel, SettingsModel
 from .qt_single_application import QtSingleApplication
 from .scheduler import VortaScheduler
 from .tray_menu import TrayMenu
-from .utils import parse_args, set_tray_icon
+from .utils import parse_args, set_tray_icon, borg_compat
 from .views.main_window import MainWindow
 from vorta.borg.version import BorgVersionThread
 
@@ -30,7 +30,6 @@ class VortaApp(QtSingleApplication):
     backup_finished_event = QtCore.pyqtSignal(dict)
     backup_cancelled_event = QtCore.pyqtSignal()
     backup_log_event = QtCore.pyqtSignal(str)
-    borg_details = {'version': '0.0', 'path': 'borg'}
 
     def __init__(self, args_raw, single_app=False):
 
@@ -112,7 +111,7 @@ class VortaApp(QtSingleApplication):
         thread.start()
 
     def set_borg_details_result(self, result):
-        self.borg_details['version'] = result['data']['version']
-        self.borg_details['path'] = result['data']['path']
+        borg_compat.set_version(result['data']['version'], result['data']['path'])
         if self._main_window_exists():
-            self.main_window.miscTab.set_borg_details(self.borg_details)
+            self.main_window.miscTab.set_borg_details(borg_compat.version, borg_compat.path)
+            self.main_window.repoTab.toggle_available_compression()

src/vorta/borg/_compatibility.py

@@ -0,0 +1,25 @@
+from pkg_resources import parse_version
+
+MIN_BORG_FOR_FEATURE = {
+    'BLAKE2': parse_version('1.1.4'),
+    'ZSTD': parse_version('1.1.4'),
+    # add new version-checks here.
+}
+
+
+class BorgCompatibility:
+    """
+    An internal class that keeps details of the Borg version
+    in use and allows checking for specific features. Could be used
+    to customize Borg commands by version in the future.
+    """
+
+    version = '0.0'
+    path = ''
+
+    def set_version(self, version, path):
+        self.version = version
+        self.path = path
+
+    def check(self, feature_name):
+        return parse_version(self.version) >= MIN_BORG_FOR_FEATURE[feature_name]

src/vorta/borg/create.py

@@ -3,9 +3,9 @@ import tempfile
 from dateutil import parser
 import subprocess
 
-from ..i18n import trans_late
-from ..utils import get_current_wifi, format_archive_name
-from ..models import SourceFileModel, ArchiveModel, WifiSettingModel, RepoModel
+from vorta.i18n import trans_late
+from vorta.utils import get_current_wifi, format_archive_name, borg_compat
+from vorta.models import SourceFileModel, ArchiveModel, WifiSettingModel, RepoModel
 from .borg_thread import BorgThread
 
 
@@ -97,6 +97,10 @@ class BorgCreateThread(BorgThread):
             ret['message'] = trans_late('messages', 'Repo folder not mounted or moved.')
             return ret
 
+        if 'zstd' in profile.compression and not borg_compat.check('ZSTD'):
+            ret['message'] = trans_late('messages', 'Your current Borg version does not support ZStd compression.')
+            return ret
+
         cmd = ['borg', 'create', '--list', '--info', '--log-json', '--json', '--filter=AM', '-C', profile.compression]
 
         # Add excludes

src/vorta/utils.py

@@ -22,10 +22,13 @@ from PyQt5.QtGui import QIcon
 from PyQt5 import QtCore
 from vorta.keyring.abc import VortaKeyring
 from vorta.log import logger
+from vorta.borg._compatibility import BorgCompatibility
 
 keyring = VortaKeyring.get_keyring()
 logger.info('Using %s Keyring implementation.', keyring.__class__.__name__)
 
+borg_compat = BorgCompatibility()
+
 
 def nested_dict():
     """

src/vorta/views/main_window.py

@@ -2,17 +2,17 @@ import sys
 from PyQt5.QtWidgets import QShortcut
 from PyQt5 import uic, QtCore
 from PyQt5.QtGui import QKeySequence
+
+from vorta.utils import get_asset, borg_compat
+from vorta.models import BackupProfileModel
+from vorta.borg.borg_thread import BorgThread
+from vorta.views.utils import get_theme_class
 from .repo_tab import RepoTab
 from .source_tab import SourceTab
 from .archive_tab import ArchiveTab
 from .schedule_tab import ScheduleTab
 from .misc_tab import MiscTab
 from .profile_add_edit_dialog import AddProfileWindow, EditProfileWindow
-from ..utils import get_asset
-from ..models import BackupProfileModel
-from vorta.borg.borg_thread import BorgThread
-from vorta.views.utils import get_theme_class
-
 
 uifile = get_asset('UI/mainwindow.ui')
 MainWindowUI, MainWindowBase = uic.loadUiType(uifile, from_imports=True, import_from=get_theme_class())
@@ -34,7 +34,7 @@ class MainWindow(MainWindowBase, MainWindowUI):
         self.archiveTab = ArchiveTab(self.archiveTabSlot)
         self.scheduleTab = ScheduleTab(self.scheduleTabSlot)
         self.miscTab = MiscTab(self.miscTabSlot)
-        self.miscTab.set_borg_details(self.app.borg_details)
+        self.miscTab.set_borg_details(borg_compat.version, borg_compat.path)
         self.tabWidget.setCurrentIndex(0)
 
         self.repoTab.repo_changed.connect(self.archiveTab.populate_from_profile)

src/vorta/views/misc_tab.py

@@ -39,6 +39,6 @@ class MiscTab(MiscTabBase, MiscTabUI, BackupProfileMixin):
         if key == 'autostart':
             open_app_at_startup(new_value)
 
-    def set_borg_details(self, borg_details):
-        self.borgVersion.setText(borg_details['version'])
-        self.borgPath.setText(borg_details['path'])
+    def set_borg_details(self, version, path):
+        self.borgVersion.setText(version)
+        self.borgPath.setText(path)

src/vorta/views/repo_add_dialog.py

@@ -1,7 +1,7 @@
 import re
 from PyQt5 import uic
 
-from ..utils import get_private_keys, get_asset, choose_file_dialog
+from vorta.utils import get_private_keys, get_asset, choose_file_dialog, borg_compat
 from vorta.borg.init import BorgInitThread
 from vorta.borg.info import BorgInfoThread
 from vorta.views.utils import get_theme_class
@@ -85,16 +85,21 @@ class AddRepoWindow(AddRepoBase, AddRepoUI):
             self._set_status(self.tr('Unable to add your repository.'))
 
     def init_encryption(self):
-        self.encryptionComboBox.addItem(self.tr('Repokey-Blake2 (Recommended, key stored in repository)'),
-                                        'repokey-blake2')
-        self.encryptionComboBox.addItem(self.tr('Repokey'),
-                                        'repokey')
-        self.encryptionComboBox.addItem(self.tr('Keyfile-Blake2 (Key stored in home directory)'),
-                                        'keyfile-blake2')
-        self.encryptionComboBox.addItem(self.tr('Keyfile'),
-                                        'keyfile')
-        self.encryptionComboBox.addItem(self.tr('None (not recommended)'),
-                                        'none')
+        encryption_algos = [
+            ['Repokey-Blake2 (Recommended, key stored in repository)', 'repokey-blake2'],
+            ['Repokey', 'repokey'],
+            ['Keyfile-Blake2 (Key stored in home directory)', 'keyfile-blake2'],
+            ['Keyfile', 'keyfile'],
+            ['None (not recommended)', 'none']
+        ]
+
+        for desc, name in encryption_algos:
+            self.encryptionComboBox.addItem(self.tr(desc), name)
+
+        if not borg_compat.check('BLAKE2'):
+            self.encryptionComboBox.model().item(0).setEnabled(False)
+            self.encryptionComboBox.model().item(2).setEnabled(False)
+            self.encryptionComboBox.setCurrentIndex(1)
 
     def init_ssh_key(self):
         keys = get_private_keys()

src/vorta/views/repo_tab.py

@@ -2,11 +2,11 @@ import os
 from PyQt5 import uic, QtCore
 from PyQt5.QtWidgets import QApplication, QMessageBox
 
-from ..models import RepoModel, ArchiveModel, BackupProfileMixin
-from .repo_add_dialog import AddRepoWindow, ExistingRepoWindow
-from ..utils import pretty_bytes, get_private_keys, get_asset
+from vorta.models import RepoModel, ArchiveModel, BackupProfileMixin
+from vorta.utils import pretty_bytes, get_private_keys, get_asset, borg_compat
 from .ssh_dialog import SSHAddWindow
-from vorta.views.utils import get_theme_class
+from .repo_add_dialog import AddRepoWindow, ExistingRepoWindow
+from .utils import get_theme_class
 
 uifile = get_asset('UI/repotab.ui')
 RepoUI, RepoBase = uic.loadUiType(uifile, from_imports=True, import_from=get_theme_class())
@@ -39,6 +39,7 @@ class RepoTab(RepoBase, RepoUI, BackupProfileMixin):
         self.repoCompression.addItem(self.tr('LZ4 (modern, default)'), 'lz4')
         self.repoCompression.addItem(self.tr('Zstandard Level 3 (modern)'), 'zstd,3')
         self.repoCompression.addItem(self.tr('Zstandard Level 8 (modern)'), 'zstd,8')
+
         # zlib and lzma come from python stdlib and are there (and in borg) since long.
         # but maybe not much reason to start with these nowadays, considering zstd supports
         # a very wide range of compression levels and has great speed. if speed is more
@@ -48,6 +49,9 @@ class RepoTab(RepoBase, RepoUI, BackupProfileMixin):
         self.repoCompression.addItem(self.tr('No Compression'), 'none')
         self.repoCompression.currentIndexChanged.connect(self.compression_select_action)
 
+        self.toggle_available_compression()
+        self.repoCompression.currentIndexChanged.connect(self.compression_select_action)
+
         self.init_ssh()
         self.sshComboBox.currentIndexChanged.connect(self.ssh_select_action)
         self.sshKeyToClipboardButton.clicked.connect(self.ssh_copy_to_clipboard_action)
@@ -88,6 +92,12 @@ class RepoTab(RepoBase, RepoUI, BackupProfileMixin):
         for key in keys:
             self.sshComboBox.addItem(f'{key["filename"]} ({key["format"]})', key['filename'])
 
+    def toggle_available_compression(self):
+        use_zstd = borg_compat.check('ZSTD')
+        for algo in ['zstd,3', 'zstd,8']:
+            ix = self.repoCompression.findData(algo)
+            self.repoCompression.model().item(ix).setEnabled(use_zstd)
+
     def ssh_select_action(self, index):
         if index == 1:
             ssh_add_window = SSHAddWindow()