add helper

app/helper/plugin.py

@@ -0,0 +1,31 @@
+from pathlib import Path
+from typing import Dict
+
+from cachetools import TTLCache, cached
+
+from app.utils.singleton import Singleton
+
+
+class PluginHelper(metaclass=Singleton):
+    """
+    插件市场管理，下载安装插件到本地
+    """
+
+    @cached(cache=TTLCache(maxsize=1, ttl=1800))
+    def get_plugins(self) -> Dict[str, dict]:
+        """
+        获取所有插件列表
+        """
+        pass
+
+    def download(self, name: str, dest: Path) -> bool:
+        """
+        下载插件到本地
+        """
+        pass
+
+    def install(self, name: str) -> bool:
+        """
+        安装插件
+        """
+        pass