Add plugin download system in backend

.gitignore

@@ -15,3 +15,11 @@ src/backend/plugins/plugins
 
 # Ignore built frontend
 public
+
+# Ignore plugin pages
+src/frontend/src/routes/plugins/**
+!src/frontend/src/routes/plugins/+layout.ts
+!src/frontend/src/routes/plugins/+page.svelte
+
+# Ignore plugin components
+src/frontend/src/lib/plugins

src/backend/plugins/downloader.py

@@ -1,38 +1,44 @@
 from typing import Optional
 
-from plugins import unpack
-from utils.const import PLUGINS_DIR, PLUGINS_DOWNLOAD
+from plugins import handler, priority, unpack, validate
+from utils.const import PLUGINS_DOWNLOAD
 
-from configparser import ConfigParser
 import logging
+import tomllib
 
 import requests
 
 
 def from_url(url: str) -> bool:
-    plugin_ini = _download_plugin_ini(url)
-    if plugin_ini is None:
+    plugin_toml = _download_plugin_toml(url)
+    if plugin_toml is None:
         return False
 
-    config = ConfigParser()
-    config.read_string(plugin_ini)
-    name = config['package'].get('name')
-    zip_url = config['package'].get('zip_url')
+    config = tomllib.loads(plugin_toml)
+    if not validate.validate_toml(config):
+        return False
+
+    name = config['plugin'].get('name').replace('-', '_')
+    zip_url = config['plugin'].get('zip_url')
 
     if not _download_plugin_zip(zip_url, name):
         return False
     if not unpack.unzip(name):
         return False
-    if not unpack.unpack(f'{PLUGINS_DIR}/{name}', 'plugin.ini'):
+    if not unpack.unpack(name, 'Plugin.toml'):
+        return False
+    if not unpack.distribute(name):
         return False
 
+    priority.add_new_plugin(name, 2)
+    handler.load(name)
     return True
 
 
-def _download_plugin_ini(url: str) -> Optional[str]:
+def _download_plugin_toml(url: str) -> Optional[str]:
     res = requests.get(url, timeout=10)
     if not res.ok:
-        logging.error(f'Can\'t download plugin.ini at "{url}"')
+        logging.error(f'Can\'t download Plugin.toml at "{url}"')
         return None
     return res.text
 

src/backend/plugins/handler.py

@@ -0,0 +1,33 @@
+from typing import Optional
+
+import importlib
+import logging
+
+from plugins.base_plugin import Plugin
+from plugins import priority
+
+
+def load_all() -> None:
+    for plugin_name, prio in priority.fetch_plugins():
+        logging.info(f'Loading plugin "{plugin_name}" with priority {prio}')
+        plugin = load(plugin_name)
+        if plugin is not None:
+            plugin.load()
+
+
+def load(name: str) -> Optional[Plugin]:
+    try:
+        source = f'plugins.plugins.{name}.backend.main'
+        plugin: Plugin = importlib.import_module(source).init()
+        return plugin
+    except TypeError:
+        # Abstract class (Plugin) does not implement methods like load & unload
+        logging.error(f'Plugin "{name}" does not implement abstract methods')
+    except AttributeError:
+        # No init() function
+        logging.error(f'Plugin "{name}" does not provide an init() function')
+    except ModuleNotFoundError:
+        # No such file
+        logging.error(f'Plugin "{name}" does not exist')
+
+    return None

src/backend/plugins/priority.py

@@ -0,0 +1,39 @@
+from typing import Generator, List, Tuple
+
+from utils.const import PLUGINS_DIR
+
+_PRIORITIES: List[Tuple[str, int]] = []
+
+
+def fetch_plugins() -> Generator[Tuple[str, int], None, None]:
+    with open(f'{PLUGINS_DIR}/priorities.csv', 'r', encoding='utf-8') as f:
+        name, priority = f.readline().strip().split(',')
+        _PRIORITIES.append((name, int(priority)))
+        yield (name, int(priority))
+        f.close()
+
+
+def add_new_plugin(name: str, priority: int) -> None:
+    for pp_pair in _PRIORITIES:
+        if pp_pair[0] == name:
+            return
+    _PRIORITIES.append((name, priority))
+    _sort_priorities()
+    _save_priorities()
+
+
+def change_plugin_priority(name: str, priority: int) -> None:
+    for i, pp_pair in enumerate(_PRIORITIES):
+        if pp_pair[0] == name:
+            _PRIORITIES[i] = (name, priority)
+
+
+def _save_priorities() -> None:
+    with open(f'{PLUGINS_DIR}/priorities.csv', 'w', encoding='utf-8') as f:
+        for prio in _PRIORITIES:
+            f.write(f'{prio[0]},{prio[1]}')
+        f.close()
+
+
+def _sort_priorities() -> None:
+    _PRIORITIES.sort(key=lambda o: o[1])

src/backend/plugins/unpack.py

@@ -1,6 +1,11 @@
 from typing import Optional
 
-from utils.const import PLUGINS_DIR, PLUGINS_DOWNLOAD
+from utils.const import (
+    FRONTEND_PAGES_DIR,
+    FRONTEND_PLUGINS_DIR,
+    PLUGINS_DIR,
+    PLUGINS_DOWNLOAD,
+)
 
 import logging
 import os
@@ -9,12 +14,18 @@
 
 
 def unzip(name: str) -> bool:
+    _clear_prev_installation(name)
     with zipfile.ZipFile(f'{PLUGINS_DOWNLOAD}/{name}.zip', 'r') as zip_ref:
         zip_ref.extractall(f'{PLUGINS_DIR}/{name}')
 
     return True
 
 
+def _clear_prev_installation(name: str) -> None:
+    if os.path.exists(f'{PLUGINS_DIR}/{name}'):
+        shutil.rmtree(f'{PLUGINS_DIR}/{name}')
+
+
 def _find_target_file(root_dir: str, target: str) -> Optional[str]:
     for dirpath, _, filenames in os.walk(root_dir):
         if target in filenames:
@@ -23,30 +34,52 @@ def _find_target_file(root_dir: str, target: str) -> Optional[str]:
 
 
 def _move_contents(target_folder, root_dir) -> bool:
-    root_parent_folder = os.path.dirname(root_dir)
     for item in os.listdir(target_folder):
         source = os.path.join(target_folder, item)
-        destination = os.path.join(root_parent_folder, item)
-
+        destination = os.path.join(root_dir, item)
         if os.path.isdir(source):
             shutil.move(source, destination)
         else:
-            shutil.move(source, root_parent_folder)
+            shutil.move(source, root_dir)
 
     # Clean up the now empty target_folder
     os.rmdir(target_folder)
 
     return True
 
 
-def unpack(root_dir: str, target: str):
+def unpack(plugin_name: str, target: str) -> bool:
+    root_dir = f'{PLUGINS_DIR}/{plugin_name}'
     target_folder = _find_target_file(root_dir, target)
     if target_folder:
         logging.info(f'Found {target} in {target_folder}')
         _move_contents(target_folder, root_dir)
 
-        # Remove the root folder after moving contents
-        shutil.rmtree(root_dir)
         logging.info('Plugin unpacked')
+        return True
+
+    logging.error(f'{target} not found in the plugin folder')
+    return False
+
+
+def distribute(plugin_name: str) -> bool:
+    # Make sure previous installations are deleted
+    _clear_frontend_installation(plugin_name)
+    root_dir = f'{PLUGINS_DIR}/{plugin_name}'
+    if os.path.exists(f'{root_dir}/frontend'):
+        shutil.move(f'{root_dir}/frontend', f'{FRONTEND_PLUGINS_DIR}/{plugin_name}')
     else:
-        logging.error(f'{target} not found in the plugin folder')
+        logging.warning(f'Frontend directorty of plugin "{plugin_name}" does not exist')
+
+    if os.path.exists(f'{root_dir}/pages'):
+        shutil.move(f'{root_dir}/pages', f'{FRONTEND_PAGES_DIR}/{plugin_name}')
+    else:
+        logging.warning(f'Pages directory of plugin "{plugin_name}" does not exist')
+    return True
+
+
+def _clear_frontend_installation(name: str) -> None:
+    if os.path.exists(f'{FRONTEND_PLUGINS_DIR}/{name}'):
+        shutil.rmtree(f'{FRONTEND_PLUGINS_DIR}/{name}')
+    if os.path.exists(f'{FRONTEND_PAGES_DIR}/{name}'):
+        shutil.rmtree(f'{FRONTEND_PAGES_DIR}/{name}')

src/backend/plugins/validate.py

@@ -0,0 +1,3 @@
+# TODO: Validate plugins TOML
+def validate_toml(toml: dict) -> bool:
+    return True

src/backend/utils/const.py

@@ -3,3 +3,7 @@
 _plugins: str = './plugins'
 PLUGINS_DIR: str = f'{_plugins}/plugins'
 PLUGINS_DOWNLOAD: str = f'{_plugins}/downloads'
+
+_frontend: str = '../frontend'
+FRONTEND_PLUGINS_DIR = f'{_frontend}/src/lib/plugins'
+FRONTEND_PAGES_DIR = f'{_frontend}/src/routes/plugins'