Implement plugin dependency installation mechanism

src/backend/config/config.toml

@@ -1,8 +1,12 @@
 [frontend]
 build = "npm run build"
+install = "npm install"
 show_output = true
 motd = "Memory: {{teal}}{{memory_used}} MB{{end}} / {{memory_total}} MB\nCPU: {{teal}}{{cpu_percent}}%{{end}}\nUsers: {{teal}}{{active_users}}{{end}}\nHave a great day!"
 
+[backend]
+install_plugin_deps = "pip install -r"
+
 [login]
 disable_statuses = []
 widgets = ["header", "version", "motd", "status", "sysinfo"]

src/backend/plugins/dependencies.py

@@ -0,0 +1,66 @@
+import json
+import logging
+import os
+import subprocess
+import sys
+
+from plugins import unpack
+from utils import config
+from utils.const import FRONTEND_PATH, PLUGINS_DIR
+
+
+def python(plugin_name: str) -> bool:
+    req_path = f'{PLUGINS_DIR}/{plugin_name}/requirements.txt'
+    if not os.path.exists(req_path):
+        logging.warning(f'"requirements.txt" for plugin "{
+            plugin_name}" does not exist')
+        return True
+
+    # TODO: Check the returned value
+    try:
+        subprocess.check_call(
+            [sys.executable, '-m', *config.fetch().get('backend').get('install_plugin_deps').split(' '), req_path])
+    except Exception as e:
+        unpack.revert(plugin_name)
+        raise e
+
+    return True
+
+
+def node(plugin_name: str) -> bool:
+    plugin_dir = f'{PLUGINS_DIR}/{plugin_name}'
+    if not os.path.exists(f'{plugin_dir}/package.json'):
+        logging.warning(f'"package.json" for plugin "{
+            plugin_name}" does not exist')
+        return True
+
+    if not _merge_dependencies(plugin_dir):
+        return False
+
+    # TODO: Check the returned value
+    subprocess.check_call(args=config.fetch().get('frontend').get(
+        'install').split(' '), cwd=FRONTEND_PATH, shell=True)
+    return True
+
+
+def _merge_dependencies(plugin_dir: str) -> bool:
+    with open(f'{plugin_dir}/package.json', 'r', encoding='utf-8') as f:
+        source_data = json.load(f)
+        plugin_dependencies = source_data.get('dependencies')
+        f.close()
+
+    with open(f'{FRONTEND_PATH}/package.json', 'r', encoding='utf-8') as f:
+        package_json = json.load(f)
+        f.close()
+    if package_json.get('dependencies') is None:
+        logging.error('Frontend\'s package.json is corrupted')
+        return False
+
+    package_json['dependencies'].update(plugin_dependencies)
+
+    with open(f'{FRONTEND_PATH}/package.json', 'w', encoding='utf-8') as f:
+        json.dump(package_json, f, indent=2)
+        f.write('\n')
+        f.close()
+
+    return True

src/backend/plugins/downloader.py

@@ -1,6 +1,6 @@
 from typing import Optional
 
-from plugins import handler, priority, unpack, validate
+from plugins import dependencies, handler, priority, unpack, validate
 from utils.const import PLUGINS_DOWNLOAD
 
 import logging
@@ -21,14 +21,27 @@ def from_url(url: str) -> bool:
     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(name, 'Plugin.toml'):
-        return False
-    if not unpack.distribute(name):
-        return False
+    try:
+        if not _download_plugin_zip(zip_url, name):
+            return False
+        if not unpack.unzip(name):
+            unpack.revert(name)
+            return False
+        if not unpack.unpack(name, 'Plugin.toml'):
+            unpack.revert(name)
+            return False
+        if not unpack.distribute(name):
+            unpack.revert(name)
+            return False
+        if not dependencies.python(name):
+            unpack.revert(name)
+            return False
+        if not dependencies.node(name):
+            unpack.revert(name)
+            return False
+    except Exception as e:
+        unpack.revert(name)
+        raise e
 
     priority.add_new_plugin(name, 2)
     handler.load(name)

src/backend/plugins/unpack.py

@@ -13,17 +13,17 @@
 import zipfile
 
 
-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}')
+def unzip(plugin_name: str) -> bool:
+    _clear_prev_installation(plugin_name)
+    with zipfile.ZipFile(f'{PLUGINS_DOWNLOAD}/{plugin_name}.zip', 'r') as zip_ref:
+        zip_ref.extractall(f'{PLUGINS_DIR}/{plugin_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 _clear_prev_installation(plugin_name: str) -> None:
+    if os.path.exists(f'{PLUGINS_DIR}/{plugin_name}'):
+        shutil.rmtree(f'{PLUGINS_DIR}/{plugin_name}')
 
 
 def _find_target_file(root_dir: str, target: str) -> Optional[str]:
@@ -67,19 +67,28 @@ def distribute(plugin_name: str) -> bool:
     _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}')
+        shutil.move(f'{root_dir}/frontend',
+                    f'{FRONTEND_PLUGINS_DIR}/{plugin_name}')
     else:
-        logging.warning(f'Frontend directorty of plugin "{plugin_name}" does not exist')
+        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')
+        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}')
+def _clear_frontend_installation(plugin_name: str) -> None:
+    if os.path.exists(f'{FRONTEND_PLUGINS_DIR}/{plugin_name}'):
+        shutil.rmtree(f'{FRONTEND_PLUGINS_DIR}/{plugin_name}')
+    if os.path.exists(f'{FRONTEND_PAGES_DIR}/{plugin_name}'):
+        shutil.rmtree(f'{FRONTEND_PAGES_DIR}/{plugin_name}')
+
+
+def revert(plugin_name: str) -> None:
+    logging.info(f'Reverting installation of plugin "{plugin_name}"')
+    _clear_prev_installation(plugin_name)
+    _clear_frontend_installation(plugin_name)