acid-state 0.7.9 → 0.7.10

raw patch · 3 files changed

+46/−32 lines, 3 filesPVP ok

version bump matches the API change (PVP)

API changes (from Hackage documentation)

Files

• acid-state.cabal +1/−1
• examples/RemoteServer.hs +7/−1
• src/Data/Acid/Local.hs +38/−30

@@ -7,7 +7,7 @@ -- The package version. See the Haskell package versioning policy -- (http://www.haskell.org/haskellwiki/Package_versioning_policy) for -- standards guiding when and how versions should be incremented.-Version:             0.7.9+Version:             0.7.10  -- A short (one-line) description of the package. Synopsis:            Add ACID guarantees to any serializable Haskell data structure.

@@ -2,6 +2,7 @@ module Main (main) where  import Data.Acid+import Data.Acid.Local import Data.Acid.Remote (acidServer)  import Control.Exception (bracket)@@ -16,6 +17,11 @@ main :: IO () main =     bracket-      (openLocalState $ StressState 0)+      (do putStrLn "Loading checkpoint"+          mkAcid <- prepareLocalState $ StressState 0+          putStrLn "Waiting for lock/replaying events"+          acid <- mkAcid+          putStrLn "Done."+          return acid)       closeAcidState       (\s -> acidServer s (PortNumber 8080))

@@ -249,42 +249,50 @@                                          --   found.                   -> Bool                -- ^ True if we should wait for the lock to be released.                   -> IO (IO (AcidState st))-resumeLocalStateFrom directory initialState doWaitForLock = do-  firstLock <- if not doWaitForLock then obtainPrefixLock lockFile else return undefined--  core <- mkCore (eventsToMethods acidEvents) initialState-  mbLastCheckpoint <- Log.newestEntry checkpointsLogKey-  n <- case mbLastCheckpoint of-         Nothing-          -> return 0-         Just (Checkpoint eventCutOff content)-          -> do modifyCoreState_ core (\_oldState -> case runGetLazy safeGet content of-                                                       Left msg  -> checkpointRestoreError msg-                                                       Right val -> return val)-                return eventCutOff-  return $ do-    secondLock <- if doWaitForLock then waitForLock lockFile else return undefined--    eventsLog <- openFileLog eventsLogKey-    events <- readEntriesFrom eventsLog n-    mapM_ (runColdMethod core) events-    ensureLeastEntryId eventsLog n-    checkpointsLog <- openFileLog checkpointsLogKey-    stateCopy <- newIORef undefined-    withCoreState core (writeIORef stateCopy)--    return $ toAcidState LocalState { localCore = core-                                    , localCopy = stateCopy-                                    , localEvents = eventsLog-                                    , localCheckpoints = checkpointsLog-                                    , localLock = if doWaitForLock then secondLock else firstLock-                                    }+resumeLocalStateFrom directory initialState doWaitForLock =+  case doWaitForLock of+    True -> do+      (n, st) <- loadCheckpoint+      return $ do+        lock    <- waitForLock lockFile+        replayEvents lock n st+    False -> do+      lock    <- obtainPrefixLock lockFile+      (n, st) <- loadCheckpoint+      return $ do+        replayEvents lock n st   where     lockFile = directory </> "open"     eventsLogKey = LogKey { logDirectory = directory                           , logPrefix = "events" }     checkpointsLogKey = LogKey { logDirectory = directory                                , logPrefix = "checkpoints" }+    loadCheckpoint = do+      mbLastCheckpoint <- Log.newestEntry checkpointsLogKey+      case mbLastCheckpoint of+        Nothing ->+          return (0, initialState)+        Just (Checkpoint eventCutOff content) -> do+          case runGetLazy safeGet content of+            Left msg  -> checkpointRestoreError msg+            Right val -> return (eventCutOff, val)+    replayEvents lock n st = do+      core <- mkCore (eventsToMethods acidEvents) st++      eventsLog <- openFileLog eventsLogKey+      events <- readEntriesFrom eventsLog n+      mapM_ (runColdMethod core) events+      ensureLeastEntryId eventsLog n+      checkpointsLog <- openFileLog checkpointsLogKey+      stateCopy <- newIORef undefined+      withCoreState core (writeIORef stateCopy)++      return $ toAcidState LocalState { localCore = core+                                      , localCopy = stateCopy+                                      , localEvents = eventsLog+                                      , localCheckpoints = checkpointsLog+                                      , localLock = lock+                                      }  waitForLock :: FilePath -> IO PrefixLock waitForLock path = go undefined