单独获取cache

backend/SystemUpdater/UpdateManager.py

@@ -2,6 +2,7 @@
 # -*- Mode: Python; indent-tabs-mode: nil; tab-width: 4; coding: utf-8 -*-
 
 import os
+from apt import Cache
 import sys
 import shutil
 import dbus
@@ -417,12 +418,12 @@ class UpdateManager():
         depends_count = 0
         _error_str = ""
         _local_satisfy = False
+        deb_cache = self.cache
         absolute_path, debname = os.path.split(deb_path)
-        if  self.cache == None:
-            logging.warning('Perform \"UpdateDetect\" first')
-            return _local_satisfy
+        if  deb_cache == None:
+            deb_cache = Cache()
         try:
-            deb = DebPackage(deb_path, self.cache)
+            deb = DebPackage(deb_path, deb_cache)
             deb.check()
             (install, remove, unauth) = deb.required_changes
         except Exception as e:
@@ -437,7 +438,7 @@ class UpdateManager():
                     # return False
                 # 需要查找本地依赖
                 elif len(install) > 0:
-                    for pkg in self.cache:
+                    for pkg in deb_cache:
                         if pkg.marked_install:
                             depends_pkg.append(pkg)
                         elif pkg.marked_upgrade: