1b2f9de · typeable/wai

git.iko.soy/typeable/wai

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Added enumerator buffer function.

1b2f9deMichael Snoyman17 years ago

Network/Wai/Enumerator.hs+28−5

compare with master

unifiedsplit

@@ -15,6 +15,8 @@ module Network.Wai.Enumerator

15 -- ** FilePath

16 , fromFile

17 , fromEitherFile

18+ -- * Filters

19+ , buffer

18 ) where

20 ) where

20import Network.Wai (Enumerator (..), Source (..))

22import Network.Wai (Enumerator (..), Source (..))

@@ -67,16 +69,16 @@ fromLBS' lbs' = Enumerator $ \iter a0 -> lbs' >>= \lbs ->

67-- deadlocked.

69-- deadlocked.

68toSource :: Enumerator -> IO Source

70toSource :: Enumerator -> IO Source

69toSource (Enumerator e) = do

71toSource (Enumerator e) = do

70− buffer <- newEmptyMVar

72+ buff <- newEmptyMVar

71− _ <- forkIO $ e (helper buffer) () >> putMVar buffer Nothing

73+ _ <- forkIO $ e (helper buff) () >> putMVar buff Nothing

72− return $ source buffer

74+ return $ source buff

73 where

75 where

74 helper :: MVar (Maybe B.ByteString)

76 helper :: MVar (Maybe B.ByteString)

75 -> ()

77 -> ()

76 -> B.ByteString

78 -> B.ByteString

77 -> IO (Either () ())

79 -> IO (Either () ())

78− helper buffer _ bs = do

80+ helper buff _ bs = do

79− putMVar buffer $ Just bs

81+ putMVar buff $ Just bs

80 return $ Right ()

82 return $ Right ()

81 source :: MVar (Maybe B.ByteString)

83 source :: MVar (Maybe B.ByteString)

82 -> Source

84 -> Source

@@ -115,3 +117,24 @@ fromFile fp = Enumerator $ \iter a0 -> withBinaryFile fp ReadMode $ \h ->

115-- be convenient for server implementations not optimizing file sending.

117-- be convenient for server implementations not optimizing file sending.

116fromEitherFile :: Either FilePath Enumerator -> Enumerator

118fromEitherFile :: Either FilePath Enumerator -> Enumerator

117fromEitherFile = either fromFile id

119fromEitherFile = either fromFile id

120+

121+-- | Buffer chunks until we have a chunk of 'defaultChunkSize', and then send

122+-- it.

123+buffer :: Enumerator -> Enumerator

124+buffer (Enumerator e) =

125+ Enumerator go

126+ where

127+ go iter seed = do

128+ res <- e (iter' iter) (B.empty, seed)

129+ case res of

130+ Left (_, seed') -> return $ Left seed'

131+ Right (buff, seed') -> iter seed' buff

132+ iter' iter (buff, seed) bs = do

133+ if B.length buff + B.length bs < defaultChunkSize

134+ then return $ Right (buff `B.append` bs, seed)

135+ else do

136+ let (x, y) = B.splitAt (defaultChunkSize - B.length buff) bs

137+ res <- iter seed $ buff `B.append` x

138+ case res of

139+ Left seed' -> return $ Left (y, seed') -- y is ignored

140+ Right seed' -> return $ Right (y, seed')

test.hs+2−1

@@ -1,5 +1,6 @@

1{-# LANGUAGE Rank2Types #-}

2import Network.Wai

3+import Network.Wai.Enumerator (buffer)

3import Network.Wai.Handler.SimpleServer

4import Network.Wai.Handler.SimpleServer

4import qualified Data.ByteString.Char8 as B8

5import qualified Data.ByteString.Char8 as B8

5import qualified Network.Wai.Source as Source

6import qualified Network.Wai.Source as Source

@@ -23,7 +24,7 @@ postResponse :: Enumerator -> IO Response

23postResponse rb = return Response

24postResponse rb = return Response

24 { status = Status200

25 { status = Status200

25 , responseHeaders = [(ContentType, B8.pack "text/plain")]

26 , responseHeaders = [(ContentType, B8.pack "text/plain")]

26− , responseBody = Right rb

27+ , responseBody = Right $ buffer rb

27 }

28 }

29index :: Either FilePath a

30index :: Either FilePath a

wai.cabal+1−1

@@ -1,5 +1,5 @@

1Name: wai

2−Version: 0.0.0

2+Version: 0.0.1

3Synopsis: Web Application Interface.

4Description: Provides a common protocol for communication between web aplications and web servers.

5License: BSD3