Enforces noninteractive shell for debian flavor

Author: DjDCH

updatewrapper/flavor/debian.py

@@ -5,13 +5,13 @@
 
 class Debian(FlavorBase):
     def update_cache(self):
-        return self.host.run('apt-get update')
+        return self.host.run('DEBIAN_FRONTEND=noninteractive apt-get update')
 
     def check_update(self):
-        return self.host.run('apt-get --show-upgraded --assume-no upgrade')
+        return self.host.run('DEBIAN_FRONTEND=noninteractive apt-get --show-upgraded --assume-no upgrade')
 
     def has_update(self, returncode, stdout, stderr):
         return to_bytes('The following packages will be upgraded') in stdout
 
     def perform_update(self):
-        return self.host.run('apt-get --show-upgraded --assume-yes upgrade')
+        return self.host.run('DEBIAN_FRONTEND=noninteractive apt-get --show-upgraded --assume-yes upgrade')