Add mkWeakMVar for Action monad

This commit is contained in:
Victor Denisov 2017-05-08 23:12:26 -07:00
parent dd6c5057f5
commit a1568d9dbf

View file

@ -56,13 +56,14 @@ import Data.Word (Word32)
import Data.Monoid (mappend)
#endif
import Data.Typeable (Typeable)
import System.Mem.Weak (Weak)
import qualified Control.Concurrent.MVar as MV
#if MIN_VERSION_base(4,6,0)
import Control.Concurrent.MVar.Lifted (MVar, newMVar, mkWeakMVar,
import Control.Concurrent.MVar.Lifted (MVar,
readMVar)
#else
import Control.Concurrent.MVar.Lifted (MVar, newMVar, addMVarFinalizer,
import Control.Concurrent.MVar.Lifted (MVar, addMVarFinalizer,
readMVar)
#endif
import Control.Applicative ((<$>))
@ -71,7 +72,6 @@ import Control.Monad (when)
import Control.Monad.Error (Error(..))
import Control.Monad.Reader (MonadReader, ReaderT, runReaderT, ask, asks, local)
import Control.Monad.Trans (MonadIO, liftIO)
import Control.Monad.Trans.Control (MonadBaseControl(..))
import Data.Binary.Put (runPut)
import Data.Bson (Document, Field(..), Label, Val, Value(String, Doc, Bool),
Javascript, at, valueAt, lookup, look, genObjectId, (=:),
@ -106,10 +106,6 @@ import qualified Data.Map as Map
import Text.Read (readMaybe)
import Data.Maybe (fromMaybe)
#if !MIN_VERSION_base(4,6,0)
--mkWeakMVar = addMVarFinalizer
#endif
-- * Monad
type Action = ReaderT MongoContext
@ -314,7 +310,7 @@ retrieveServerData = do
type Collection = Text
-- ^ Collection name (not prefixed with database)
allCollections :: (MonadIO m, MonadBaseControl IO m) => Action m [Collection]
allCollections :: MonadIO m => Action m [Collection]
-- ^ List all collections in this database
allCollections = do
p <- asks mongoPipe
@ -825,7 +821,7 @@ query :: Selector -> Collection -> Query
-- ^ Selects documents in collection that match selector. It uses no query options, projects all fields, does not skip any documents, does not limit result size, uses default batch size, does not sort, does not hint, and does not snapshot.
query sel col = Query [] (Select sel col) [] 0 0 [] False 0 []
find :: (MonadIO m, MonadBaseControl IO m) => Query -> Action m Cursor
find :: MonadIO m => Query -> Action m Cursor
-- ^ Fetch documents satisfying query
find q@Query{selection, batchSize} = do
db <- thisDatabase
@ -1007,16 +1003,13 @@ fulfill = liftIO
data Cursor = Cursor FullCollection BatchSize (MVar DelayedBatch)
-- ^ Iterator over results of a query. Use 'next' to iterate or 'rest' to get all results. A cursor is closed when it is explicitly closed, all results have been read from it, garbage collected, or not used for over 10 minutes (unless 'NoCursorTimeout' option was specified in 'Query'). Reading from a closed cursor raises a 'CursorNotFoundFailure'. Note, a cursor is not closed when the pipe is closed, so you can open another pipe to the same server and continue using the cursor.
newCursor :: (MonadIO m, MonadBaseControl IO m) => Database -> Collection -> BatchSize -> DelayedBatch -> Action m Cursor
newCursor :: MonadIO m => Database -> Collection -> BatchSize -> DelayedBatch -> Action m Cursor
-- ^ Create new cursor. If you don't read all results then close it. Cursor will be closed automatically when all results are read from it or when eventually garbage collected.
newCursor db col batchSize dBatch = do
var <- newMVar dBatch
var <- liftIO $ MV.newMVar dBatch
let cursor = Cursor (db <.> col) batchSize var
_ <- mkWeakMVar var (closeCursor cursor)
_ <- liftDB $ mkWeakMVar var (closeCursor cursor)
return cursor
#if !MIN_VERSION_base(4,6,0)
where mkWeakMVar = addMVarFinalizer
#endif
nextBatch :: MonadIO m => Cursor -> Action m [Document]
-- ^ Return next batch of documents in query result, which will be empty if finished.
@ -1210,7 +1203,7 @@ mapReduce :: Collection -> MapFun -> ReduceFun -> MapReduce
-- ^ MapReduce on collection with given map and reduce functions. Remaining attributes are set to their defaults, which are stated in their comments.
mapReduce col map' red = MapReduce col map' red [] [] 0 Inline Nothing [] False
runMR :: (MonadIO m, MonadBaseControl IO m) => MapReduce -> Action m Cursor
runMR :: MonadIO m => MapReduce -> Action m Cursor
-- ^ Run MapReduce and return cursor of results. Error if map/reduce fails (because of bad Javascript)
runMR mr = do
res <- runMR' mr
@ -1249,6 +1242,15 @@ modifyMVar v f = do
ctx <- ask
liftIO $ MV.modifyMVar v (\x -> runReaderT (f x) ctx)
mkWeakMVar :: MVar a -> Action IO () -> Action IO (Weak (MVar a))
mkWeakMVar m closing = do
ctx <- ask
#if MIN_VERSION_base(4,6,0)
liftIO $ MV.mkWeakMVar m $ runReaderT closing ctx
#else
liftIO $ MV.addMVarFinalizer m $ runReaderT closing ctx
#endif
{- Authors: Tony Hannan <tony@10gen.com>
Copyright 2011 10gen Inc.