| Safe Haskell | Safe-Inferred |
|---|---|
| Language | Haskell2010 |
Ouroboros.Consensus.Node.Recovery
Synopsis
- newtype LastShutDownWasClean = LastShutDownWasClean Bool
- createCleanShutdownMarker ∷ IOLike m ⇒ HasFS m h → m ()
- hasCleanShutdownMarker ∷ HasFS m h → m Bool
- removeCleanShutdownMarker ∷ HasFS m h → m ()
- runWithCheckedDB ∷ ∀ a m h blk. (IOLike m, StandardHash blk, Typeable blk) ⇒ Proxy blk → HasFS m h → (LastShutDownWasClean → (ChainDB m blk → m a → m a) → m a) → m a
Documentation
newtype LastShutDownWasClean Source #
Did the ChainDB already have existing clean-shutdown marker on disk?
Constructors
| LastShutDownWasClean Bool |
Instances
| Show LastShutDownWasClean Source # | |
Defined in Ouroboros.Consensus.Node.Recovery Methods showsPrec ∷ Int → LastShutDownWasClean → ShowS # show ∷ LastShutDownWasClean → String # showList ∷ [LastShutDownWasClean] → ShowS # | |
| Eq LastShutDownWasClean Source # | |
Defined in Ouroboros.Consensus.Node.Recovery Methods | |
createCleanShutdownMarker ∷ IOLike m ⇒ HasFS m h → m () Source #
Create the cleanShutdownMarkerFile.
Idempotent.
hasCleanShutdownMarker ∷ HasFS m h → m Bool Source #
Return True when cleanShutdownMarkerFile exists.
removeCleanShutdownMarker ∷ HasFS m h → m () Source #
Remove cleanShutdownMarkerFile.
Will throw an FsResourceDoesNotExist error when it does not exist.
runWithCheckedDB ∷ ∀ a m h blk. (IOLike m, StandardHash blk, Typeable blk) ⇒ Proxy blk → HasFS m h → (LastShutDownWasClean → (ChainDB m blk → m a → m a) → m a) → m a Source #
A bracket function that manages the clean-shutdown marker on disk.
- If the marker is missing on startup, then ChainDB initialization will revalidate the database contents.
- If the OS kills the nodes, then we don't have the opportunity to write out the marker file, which is fine, since we want the next startup to do revalidation.
- If initialization was cleanly interrupted (eg SIGINT), then we leave the marker the marker in the same state as it was at the beginning of said initialization.
- At the end of a successful initialization, we remove the marker and install
a shutdown handler that writes the marker except for certain exceptions
(see
exceptionRequiresRecovery) that indicate corruption, for which we want the next startup to do revalidation.