[core] feature: new configuration file to disable packaging formats management globally

CHANGELOG.md

@@ -6,6 +6,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ## [0.9.23]
 ### Features
+- General
+  - new configuration file `/etc/bauh/gems.forbidden` can be used by system administrators/distribution package managers to disable the management of supported packaging formats globally (more on that [here](https://github.com/vinifmor/bauh#forbidden_gems))
+
 - Arch
   - allowing AUR packages to be installed when bauh is launched by the root user [#196](https://github.com/vinifmor/bauh/issues/196)
     - it creates a non-root user called **bauh-aur** for building the packages (`useradd` and `runuser` commands must be installed)

README.md

@@ -15,22 +15,23 @@ Key features
 
 
 ## Index
-1.  [Installation](#installation)
+1. [Installation](#installation)
     - [Ubuntu-based distros (20.04)](#inst_ubuntu)
     - [Arch-based distros](#inst_arch)
-2.  [Isolated installation](#inst_iso)
-3.  [Desktop entry / menu shortcut](#desk_entry)
-4.  [Autostart: tray mode](#autostart)
-5.  [Distribution](#dist)
-6.  [Supported types](#types)
+2. [Isolated installation](#inst_iso)
+3. [Desktop entry / menu shortcut](#desk_entry)
+4. [Autostart: tray mode](#autostart)
+5. [Distribution](#dist)
+6. [Supported types](#types)
     - [AppImage](#type_appimage)
     - [Arch packages/AUR](#type_arch)
     - [Flatpak](#type_flatpak)
     - [Snap](#type_snap)
     - [Native Web applications](#type_web)
-7.  [General settings](#settings)
-8.  [Directory structure, caching and logs](#dirs)
-9.  [Custom themes](#custom_themes)
+7. [General settings](#settings)
+   - [Forbidden packaging formats](#forbidden_gems)
+8. [Directory structure, caching and logs](#dirs)
+9. [Custom themes](#custom_themes)
 10. [Tray icons](#tray_icons)
 11. [CLI (Command Line Interface)](#cli)
 12. [Improving performance](#performance)
@@ -413,6 +414,16 @@ boot:
     load_apps: true  # if the installed applications or suggestions should be loaded on the management panel after the initialization process. Default: true.
 ```
 
+##### <a name="forbidden_gems">Forbidden packaging formats</a>
+- System administrators and package managers of Linux distributions can disable the usage/management of supported packaging formats
+by adding their ids to the file `/etc/bauh/gems.forbidden`. This will prevent their management code to be loaded.
+- Example (one id per line):
+```
+arch
+appimage
+# flatpak  # 'sharps' can be used to ignore a given line (comment)
+```
+
 #### <a name="dirs">Directory structure, caching and logs</a>
 - `~/.config/bauh` (or `/etc/bauh` for **root**): stores configuration files
 - `~/.cache/bauh` (or `/var/cache/bauh` for **root**): stores data about your installed applications, databases, indexes, etc. Files are stored here to provide a faster initialization and data recovery. 

bauh/cli/app.py

@@ -49,7 +49,8 @@ def main():
                                  internet_checker=InternetChecker(offline=False),
                                  root_user=user.is_root())
 
-    managers = gems.load_managers(context=context, locale=i18n.current_key, config=app_config, default_locale=DEFAULT_I18N_KEY)
+    managers = gems.load_managers(context=context, locale=i18n.current_key, config=app_config,
+                                  default_locale=DEFAULT_I18N_KEY, logger=logger)
 
     cli = CLIManager(GenericSoftwareManager(managers, context=context, config=app_config))
 

bauh/manage.py

@@ -45,7 +45,8 @@ def new_manage_panel(app_args: Namespace, app_config: dict, logger: logging.Logg
                                  internet_checker=InternetChecker(offline=app_args.offline),
                                  root_user=user.is_root())
 
-    managers = gems.load_managers(context=context, locale=i18n.current_key, config=app_config, default_locale=DEFAULT_I18N_KEY)
+    managers = gems.load_managers(context=context, locale=i18n.current_key, config=app_config,
+                                  default_locale=DEFAULT_I18N_KEY, logger=logger)
 
     if app_args.reset:
         util.clean_app_files(managers)

bauh/view/core/gems.py

@@ -1,12 +1,15 @@
 import inspect
 import os
 import pkgutil
-from typing import List
+from logging import Logger
+from typing import List, Generator
 
-from bauh import ROOT_DIR
+from bauh import __app_name__, ROOT_DIR
 from bauh.api.abstract.controller import SoftwareManager, ApplicationContext
 from bauh.view.util import translation
 
+FORBIDDEN_GEMS_FILE = f'/etc/{__app_name__}/gems.forbidden'
+
 
 def find_manager(member):
     if not isinstance(member, str):
@@ -19,11 +22,33 @@ def find_manager(member):
                     return manager_found
 
 
-def load_managers(locale: str, context: ApplicationContext, config: dict, default_locale: str) -> List[SoftwareManager]:
+def read_forbidden_gems() -> Generator[str, None, None]:
+    try:
+        with open(FORBIDDEN_GEMS_FILE) as f:
+            forbidden_lines = f.readlines()
+
+        for line in forbidden_lines:
+            clean_line = line.strip()
+
+            if clean_line and not clean_line.startswith('#'):
+                yield clean_line
+
+    except FileNotFoundError:
+        pass
+
+
+def load_managers(locale: str, context: ApplicationContext, config: dict, default_locale: str, logger: Logger) -> List[SoftwareManager]:
     managers = []
 
+    forbidden_gems = {gem for gem in read_forbidden_gems()}
+
     for f in os.scandir(f'{ROOT_DIR}/gems'):
         if f.is_dir() and f.name != '__pycache__':
+
+            if f.name in forbidden_gems:
+                logger.warning(f"gem '{f.name}' could not be loaded because it was marked as forbidden in '{FORBIDDEN_GEMS_FILE}'")
+                continue
+
             loader = pkgutil.find_loader(f'bauh.gems.{f.name}.controller')
 
             if loader: