fix actions

app/actions/fetch_downloads.py

@@ -1,5 +1,4 @@
 from app.actions import BaseAction
-from app.chain.download import DownloadChain
 from app.schemas import ActionParams, ActionContext
 
 
@@ -17,10 +16,6 @@ class FetchDownloadsAction(BaseAction):
 
     _downloads = []
 
-    def __init__(self):
-        super().__init__()
-        self.downloadchain = DownloadChain()
-
     @property
     def name(self) -> str:
         return "获取下载任务"
@@ -41,7 +36,7 @@ class FetchDownloadsAction(BaseAction):
         """
         self._downloads = context.downloads
         for download in self._downloads:
-            torrents = self.downloadchain.list_torrents(hashs=[download.download_id])
+            torrents = self.chain.list_torrents(hashs=[download.download_id])
             if not torrents:
                 download.completed = True
                 continue