add key stability checking interface

Needed for resuming from chunks.

Url keys are considered not stable. I considered treating url keys with a
known size as stable, but just don't feel that is enough information.
This commit is contained in:
Joey Hess 2014-07-27 12:33:46 -04:00
parent aad8cfe718
commit 13bbb61a51
5 changed files with 18 additions and 1 deletions

View file

@ -25,6 +25,9 @@ backend = Backend
, fsckKey = Nothing
, canUpgradeKey = Nothing
, fastMigrate = Nothing
-- The content of an url can change at any time, so URL keys are
-- not stable.
, isStableKey = const False
}
{- Every unique url has a corresponding key. -}