module Network.HTTP.Lucu.Resource
( Resource
+
+ , getConfig -- Resource Config
+ , getMethod -- Resource Method
+ , getHeader -- String -> Resource (Maybe String)
+ , getAccept -- Resource [MIMEType]
+ , getContentType -- Resource (Maybe MIMEType)
+
+ , foundEntity -- ETag -> ClockTime -> Resource ()
+ , foundETag -- ETag -> Resource ()
+ , foundTimeStamp -- ClockTime -> Resource ()
+ , foundNoEntity -- Maybe String -> Resource ()
+
+ , input -- Int -> Resource String
+ , inputChunk -- Int -> Resource String
+ , inputBS -- Int -> Resource ByteString
+ , inputChunkBS -- Int -> Resource ByteString
+ , defaultLimit -- Int
+
+ , setStatus -- StatusCode -> Resource ()
+ , setHeader -- String -> String -> Resource ()
+ , redirect -- StatusCode -> URI -> Resource ()
+ , setETag -- ETag -> Resource ()
+ , setLastModified -- ClockTime -> Resource ()
+ , setContentType -- MIMEType -> Resource ()
+
+ , output -- String -> Resource ()
+ , outputChunk -- String -> Resource ()
+ , outputBS -- ByteString -> Resource ()
+ , outputChunkBS -- ByteString -> Resource ()
+
+ , driftTo -- InteractionState -> Resource ()
)
where
-import Control.Monad.State
+import Control.Concurrent.STM
+import Control.Monad.Reader
import qualified Data.ByteString.Lazy.Char8 as B
import Data.ByteString.Lazy.Char8 (ByteString)
+import Data.List
+import Data.Maybe
+import GHC.Conc (unsafeIOToSTM)
+import Network.HTTP.Lucu.Abortion
+import Network.HTTP.Lucu.Config
+import Network.HTTP.Lucu.DefaultPage
+import Network.HTTP.Lucu.ETag
+import qualified Network.HTTP.Lucu.Headers as H
+import Network.HTTP.Lucu.HttpVersion
+import Network.HTTP.Lucu.Interaction
+import Network.HTTP.Lucu.Parser
+import Network.HTTP.Lucu.Postprocess
+import Network.HTTP.Lucu.RFC1123DateTime
+import Network.HTTP.Lucu.Request
+import Network.HTTP.Lucu.Response
+import Network.HTTP.Lucu.MIMEType
+import Network.HTTP.Lucu.Utils
+import Network.URI
+import System.Time
+
+
+type Resource a = ReaderT Interaction IO a
+
+
+getConfig :: Resource Config
+getConfig = do itr <- ask
+ return $ itrConfig itr
+
+
+getMethod :: Resource Method
+getMethod = do itr <- ask
+ return $ reqMethod $ fromJust $ itrRequest itr
+
+
+getHeader :: String -> Resource (Maybe String)
+getHeader name = do itr <- ask
+ return $ H.getHeader name $ fromJust $ itrRequest itr
+
+
+getAccept :: Resource [MIMEType]
+getAccept = do accept <- getHeader "Accept"
+ if accept == Nothing then
+ return []
+ else
+ case parseStr mimeTypeListP $ fromJust accept of
+ (Success xs, _) -> return xs
+ _ -> return []
+
+
+getContentType :: Resource (Maybe MIMEType)
+getContentType = do cType <- getHeader "Content-Type"
+ if cType == Nothing then
+ return Nothing
+ else
+ case parseStr mimeTypeP $ fromJust cType of
+ (Success t, _) -> return $ Just t
+ _ -> return Nothing
+
+
+
+{- ExaminingRequest 時に使用するアクション群 -}
+
+foundEntity :: ETag -> ClockTime -> Resource ()
+foundEntity tag timeStamp
+ = do driftTo ExaminingRequest
+
+ method <- getMethod
+ when (method == GET || method == HEAD)
+ $ setHeader' "Last-Modified" $ formatHTTPDateTime timeStamp
+ foundETag tag
+
+ driftTo GettingBody
+
+
+foundETag :: ETag -> Resource ()
+foundETag tag
+ = do driftTo ExaminingRequest
+
+ method <- getMethod
+ when (method == GET || method == HEAD)
+ $ setHeader' "ETag" $ show tag
+
+ -- If-Match があればそれを見る。
+ ifMatch <- getHeader "If-Match"
+ case ifMatch of
+ Nothing -> return ()
+ Just "*" -> return ()
+ Just list -> case parseStr eTagListP list of
+ (Success tags, _)
+ -- tags の中に一致するものが無ければ
+ -- PreconditionFailed で終了。
+ -> when (not $ any (== tag) tags)
+ $ abort PreconditionFailed []
+ $ Just ("The entity tag doesn't match: " ++ list)
+ _ -> abort BadRequest [] $ Just ("Unparsable If-Match: " ++ fromJust ifMatch)
+
+ let statusForNoneMatch = if method == GET || method == HEAD then
+ NotModified
+ else
+ PreconditionFailed
+
+ -- If-None-Match があればそれを見る。
+ ifNoneMatch <- getHeader "If-None-Match"
+ case ifNoneMatch of
+ Nothing -> return ()
+ Just "*" -> abort statusForNoneMatch [] $ Just ("The entity tag matches: *")
+ Just list -> case parseStr eTagListP list of
+ (Success tags, _)
+ -> when (any (== tag) tags)
+ $ abort statusForNoneMatch [] $ Just ("The entity tag matches: " ++ list)
+ _ -> abort BadRequest [] $ Just ("Unparsable If-None-Match: " ++ list)
+
+ driftTo GettingBody
+
+
+foundTimeStamp :: ClockTime -> Resource ()
+foundTimeStamp timeStamp
+ = do driftTo ExaminingRequest
+
+ method <- getMethod
+ when (method == GET || method == HEAD)
+ $ setHeader' "Last-Modified" $ formatHTTPDateTime timeStamp
+
+ let statusForIfModSince = if method == GET || method == HEAD then
+ NotModified
+ else
+ PreconditionFailed
+
+ -- If-Modified-Since があればそれを見る。
+ ifModSince <- getHeader "If-Modified-Since"
+ case ifModSince of
+ Just str -> case parseHTTPDateTime str of
+ Just lastTime
+ -> when (timeStamp <= lastTime)
+ $ abort statusForIfModSince []
+ $ Just ("The entity has not been modified since " ++ str)
+ Nothing
+ -> return () -- 不正な時刻は無視
+ Nothing -> return ()
+
+ -- If-Unmodified-Since があればそれを見る。
+ ifUnmodSince <- getHeader "If-Unmodified-Since"
+ case ifUnmodSince of
+ Just str -> case parseHTTPDateTime str of
+ Just lastTime
+ -> when (timeStamp > lastTime)
+ $ abort PreconditionFailed []
+ $ Just ("The entity has not been modified since " ++ str)
+ Nothing
+ -> return () -- 不正な時刻は無視
+ Nothing -> return ()
+
+ driftTo GettingBody
+
+
+foundNoEntity :: Maybe String -> Resource ()
+foundNoEntity msgM
+ = do driftTo ExaminingRequest
+
+ method <- getMethod
+ when (method /= PUT)
+ $ abort NotFound [] msgM
+
+ -- エンティティが存在しないと云ふ事は、"*" も含めたどのやうな
+ -- If-Match: 條件も滿たさない。
+ ifMatch <- getHeader "If-Match"
+ when (ifMatch /= Nothing)
+ $ abort PreconditionFailed [] msgM
+
+ driftTo GettingBody
+
+
+{- GettingBody 時に使用するアクション群 -}
+
+input :: Int -> Resource String
+input limit = inputBS limit >>= return . B.unpack
+
+
+-- 多くとも limit バイトまでのリクエストボディ全體を受信する。limit が
+-- 零以下なら Config で設定されたデフォルトのボディ長により制限される。
+inputBS :: Int -> Resource ByteString
+inputBS limit
+ = do driftTo GettingBody
+ itr <- ask
+ hasBody <- liftIO $ atomically $ readItr itr itrRequestHasBody id
+ chunk <- if hasBody then
+ askForInput itr
+ else
+ do driftTo DecidingHeader
+ return B.empty
+ return chunk
+ where
+ askForInput :: Interaction -> Resource ByteString
+ askForInput itr
+ = do let defaultLimit = cnfMaxEntityLength $ itrConfig itr
+ actualLimit = if limit <= 0 then
+ defaultLimit
+ else
+ limit
+ when (actualLimit <= 0)
+ $ fail ("inputBS: limit must be positive: " ++ show actualLimit)
+ -- Reader にリクエスト
+ liftIO $ atomically
+ $ do chunkLen <- readItr itr itrReqChunkLength id
+ writeItr itr itrWillReceiveBody True
+ if fmap (> actualLimit) chunkLen == Just True then
+ -- 受信前から多過ぎる事が分かってゐる
+ tooLarge actualLimit
+ else
+ writeItr itr itrReqBodyWanted $ Just actualLimit
+ -- 應答を待つ。トランザクションを分けなければ當然デッドロック。
+ chunk <- liftIO $ atomically
+ $ do chunk <- readItr itr itrReceivedBody id
+ chunkIsOver <- readItr itr itrReqChunkIsOver id
+ if B.length chunk < fromIntegral actualLimit then
+ -- 要求された量に滿たなくて、まだ殘り
+ -- があるなら再試行。
+ unless chunkIsOver
+ $ retry
+ else
+ -- 制限値一杯まで讀むやうに指示したの
+ -- にまだ殘ってゐるなら、それは多過ぎ
+ -- る。
+ unless chunkIsOver
+ $ tooLarge actualLimit
+ -- 成功。itr 内にチャンクを置いたままにす
+ -- るとメモリの無駄になるので除去。
+ writeItr itr itrReceivedBody B.empty
+ return chunk
+ driftTo DecidingHeader
+ return chunk
+
+ tooLarge :: Int -> STM ()
+ tooLarge lim = abortSTM RequestEntityTooLarge []
+ $ Just ("Request body must be smaller than "
+ ++ show lim ++ " bytes.")
+
+
+inputChunk :: Int -> Resource String
+inputChunk limit = inputChunkBS limit >>= return . B.unpack
+
+
+-- 多くとも limit バイトまでのリクエストボディの一部を受信する。limit
+-- が 0 以下なら Config で設定されたデフォルトのボディ長により制限され
+-- る。これ以上ボディが殘ってゐなければ空文字列を返す。
+inputChunkBS :: Int -> Resource ByteString
+inputChunkBS limit
+ = do driftTo GettingBody
+ itr <- ask
+ hasBody <- liftIO $ atomically $ readItr itr itrRequestHasBody id
+ chunk <- if hasBody then
+ askForInput itr
+ else
+ do driftTo DecidingHeader
+ return B.empty
+ return chunk
+ where
+ askForInput :: Interaction -> Resource ByteString
+ askForInput itr
+ = do let defaultLimit = cnfMaxEntityLength $ itrConfig itr
+ actualLimit = if limit < 0 then
+ defaultLimit
+ else
+ limit
+ when (actualLimit <= 0)
+ $ fail ("inputChunkBS: limit must be positive: " ++ show actualLimit)
+ -- Reader にリクエスト
+ liftIO $ atomically
+ $ do writeItr itr itrReqBodyWanted $ Just actualLimit
+ writeItr itr itrWillReceiveBody True
+ -- 應答を待つ。トランザクションを分けなければ當然デッドロック。
+ chunk <- liftIO $ atomically
+ $ do chunk <- readItr itr itrReceivedBody id
+ -- 要求された量に滿たなくて、まだ殘りがあ
+ -- るなら再試行。
+ when (B.length chunk < fromIntegral actualLimit)
+ $ do chunkIsOver <- readItr itr itrReqChunkIsOver id
+ unless chunkIsOver
+ $ retry
+ -- 成功
+ writeItr itr itrReceivedBody B.empty
+ return chunk
+ when (B.null chunk)
+ $ driftTo DecidingHeader
+ return chunk
+
+
+defaultLimit :: Int
+defaultLimit = (-1)
+
+
+
+{- DecidingHeader 時に使用するアクション群 -}
+
+setStatus :: StatusCode -> Resource ()
+setStatus code
+ = do driftTo DecidingHeader
+ itr <- ask
+ liftIO $ atomically $ updateItr itr itrResponse
+ $ \ resM -> case resM of
+ Nothing -> Just $ Response {
+ resVersion = HttpVersion 1 1
+ , resStatus = code
+ , resHeaders = []
+ }
+ Just res -> Just $ res {
+ resStatus = code
+ }
+
+
+setHeader :: String -> String -> Resource ()
+setHeader name value
+ = driftTo DecidingHeader >> setHeader' name value
+
+
+setHeader' :: String -> String -> Resource()
+setHeader' name value
+ = do itr <- ask
+ liftIO $ atomically $ updateItr itr itrResponse
+ $ \ resM -> case resM of
+ Nothing -> Just $ Response {
+ resVersion = HttpVersion 1 1
+ , resStatus = Ok
+ , resHeaders = [ (name, value) ]
+ }
+ Just res -> Just $ H.setHeader name value res
+
+
+redirect :: StatusCode -> URI -> Resource ()
+redirect code uri
+ = do when (code == NotModified || not (isRedirection code))
+ $ abort InternalServerError []
+ $ Just ("Attempted to redirect with status " ++ show code)
+ setStatus code
+ setHeader "Location" (uriToString id uri $ "")
+
+
+setETag :: ETag -> Resource ()
+setETag tag
+ = setHeader "ETag" $ show tag
+
+
+setLastModified :: ClockTime -> Resource ()
+setLastModified lastmod
+ = setHeader "Last-Modified" $ formatHTTPDateTime lastmod
+
+
+setContentType :: MIMEType -> Resource ()
+setContentType mType
+ = setHeader "Content-Type" $ show mType
+
+
+{- DecidingBody 時に使用するアクション群 -}
+
+output :: String -> Resource ()
+output = outputBS . B.pack
+
+
+outputBS :: ByteString -> Resource ()
+outputBS str = do outputChunkBS str
+ driftTo Done
+
+
+outputChunk :: String -> Resource ()
+outputChunk = outputChunkBS . B.pack
+
+
+{- チャンクの大きさは Config で制限されてゐる。もし例へば /dev/zero を
+ B.readFile して作った ByteString をそのまま ResponseWriter に渡した
+ りすると大變な事が起こる。何故なら ResponseWriter は
+ Transfer-Encoding: chunked の時、ヘッダを書く爲にチャンクの大きさを
+ 測るから、その時に起こるであらう事は言ふまでも無い。 -}
+
+outputChunkBS :: ByteString -> Resource ()
+outputChunkBS str
+ = do driftTo DecidingBody
+ unless (B.null str)
+ $ do itr <- ask
+
+ let limit = cnfMaxOutputChunkLength $ itrConfig itr
+ when (limit <= 0)
+ $ fail ("cnfMaxOutputChunkLength must be positive: "
+ ++ show limit)
+
+ sendChunks str limit
+
+ liftIO $ atomically $
+ writeItr itr itrBodyIsNull False
+ where
+ sendChunks :: ByteString -> Int -> Resource ()
+ sendChunks str limit
+ | B.null str = return ()
+ | otherwise = do let (chunk, remaining) = B.splitAt (fromIntegral limit) str
+ itr <- ask
+ liftIO $ atomically $
+ do buf <- readItr itr itrBodyToSend id
+ if B.null buf then
+ -- バッファが消化された
+ writeItr itr itrBodyToSend chunk
+ else
+ -- 消化されるのを待つ
+ retry
+ -- 殘りのチャンクについて繰り返す
+ sendChunks remaining limit
+
+{-
+
+ [GettingBody からそれ以降の状態に遷移する時]
+
+ body を讀み終へてゐなければ、殘りの body を讀み捨てる。
+
+
+ [DecidingHeader からそれ以降の状態に遷移する時]
+
+ postprocess する。
+
+
+ [Done に遷移する時]
+
+ bodyIsNull が False ならば何もしない。True だった場合は出力補完す
+ る。Content-Type も變はる。但し（デフォルトのまま）Status が 200 OK
+ だった場合は、補完の代はりに 204 No Content に變へる。
+
+-}
+
+driftTo :: InteractionState -> Resource ()
+driftTo newState
+ = do itr <- ask
+ liftIO $ atomically $ do oldState <- readItr itr itrState id
+ if newState < oldState then
+ throwStateError oldState newState
+ else
+ do let a = [oldState .. newState]
+ b = tail a
+ c = zip a b
+ mapM_ (uncurry $ drift itr) c
+ writeItr itr itrState newState
+ where
+ throwStateError :: Monad m => InteractionState -> InteractionState -> m a
+
+ throwStateError Done DecidingBody
+ = fail "It makes no sense to output something after finishing to output."
+
+ throwStateError old new
+ = fail ("state error: " ++ show old ++ " ==> " ++ show new)
+
+
+ drift :: Interaction -> InteractionState -> InteractionState -> STM ()
+
+ drift itr GettingBody _
+ = writeItr itr itrReqBodyWasteAll True
+
+ drift itr DecidingHeader _
+ = postprocess itr
+
+ drift itr _ Done
+ = do bodyIsNull <- readItr itr itrBodyIsNull id
+ when bodyIsNull
+ $ do status <- readStatus itr
+ if status == Ok then
+ do updateItrF itr itrResponse
+ $ \ res -> res { resStatus = NoContent }
+ updateItrF itr itrResponse
+ $ H.deleteHeader "Content-Type"
+ updateItrF itr itrResponse
+ $ H.deleteHeader "ETag"
+ updateItrF itr itrResponse
+ $ H.deleteHeader "Last-Modified"
+ else
+ writeDefaultPage itr
+
-data ResState = ResState -- FIXME
+ drift _ _ _
+ = return ()
-type ResourceT m a = StateT ResState m a
-type Resource a = ResourceT IO a
+ readStatus :: Interaction -> STM StatusCode
+ readStatus itr = readItr itr itrResponse (resStatus . fromJust)
\ No newline at end of file
projects / Lucu.git / blobdiff