+{-# LANGUAGE
+ DoAndIfThenElse
+ , OverloadedStrings
+ , RecordWildCards
+ , UnicodeSyntax
+ #-}
module Network.HTTP.Lucu.Postprocess
- ( postprocess -- Interaction -> STM ()
- , completeUnconditionalHeaders -- Response -> IO Response
+ ( postprocess
+ , completeUnconditionalHeaders
)
where
-
-import Control.Concurrent.STM
-import Control.Monad
-import Data.Char
-import Data.Maybe
-import GHC.Conc (unsafeIOToSTM)
-import Network.HTTP.Lucu.Headers
-import Network.HTTP.Lucu.HttpVersion
-import Network.HTTP.Lucu.Interaction
-import Network.HTTP.Lucu.RFC1123DateTime
-import Network.HTTP.Lucu.Request
-import Network.HTTP.Lucu.Response
-import Network.HTTP.Lucu.Utils
-import System.Time
+import Control.Applicative
+import Control.Concurrent.STM
+import Control.Monad
+import Control.Monad.Unicode
+import Data.Ascii (Ascii, CIAscii)
+import qualified Data.Ascii as A
+import Data.Monoid.Unicode
+import Data.Time
+import qualified Data.Time.HTTP as HTTP
+import GHC.Conc (unsafeIOToSTM)
+import Network.HTTP.Lucu.Abortion
+import Network.HTTP.Lucu.Config
+import Network.HTTP.Lucu.Headers
+import Network.HTTP.Lucu.HttpVersion
+import Network.HTTP.Lucu.Interaction
+import Network.HTTP.Lucu.Request
+import Network.HTTP.Lucu.Response
+import Prelude.Unicode
{-
+ TODO: Tanslate this memo into English. It doesn't make sense to
+ non-Japanese speakers.
- * Response が未設定なら、HTTP/1.1 500 Internal Server Error にする。
+ * Response が未設定なら、200 OK にする。
+
+ * ステータスが 2xx, 3xx, 4xx, 5xx のいずれでもなければ 500 にする。
+
+ * 405 Method Not Allowed なのに Allow ヘッダが無ければ 500 にする。
- * Content-Length があれば、それを削除する。
+ * 304 Not Modified 以外の 3xx なのに Location ヘッダが無ければ 500 に
+ する。
- * HTTP/1.1 であり、且つ body を持つ事が出來る時、Transfer-Encoding の
- 最後の要素が chunked でなければ 500 Internal Error にする。
- Transfer-Encoding が未設定であれば、chunked に設定する。
+ * Content-Length があれば、それを削除する。Transfer-Encoding があって
+ も削除する。
- * HTTP/1.0 なのに Transfer-Encoding が設定濟なら 500 Internal Server
- Error にする。但し identity だけは許す。
+ * HTTP/1.1 であり、body を持つ事が出來る時、Transfer-Encoding を
+ chunked に設定する。
- * body を持つ事が出來る時、Content-Type が無ければ
- application/octet-stream にする。出來ない時、HEAD でなければ
- Content-Type を削除する。
+ * body を持つ事が出來る時、Content-Type が無ければデフォルト値にする。
+ 出來ない時、HEAD でなければContent-Type, Etag, Last-Modified を削除
+ する。
* body を持つ事が出來ない時、body 破棄フラグを立てる。
-}
-{- Postprocess は body を補完した後で實行する事 -}
-
-postprocess :: Interaction -> STM ()
-postprocess itr
- = do res <- readItr itr itrResponse id
-
- when (res == Nothing)
- $ setStatus itr InternalServerError
-
- when (itrRequest itr /= Nothing)
- $ relyOnRequest itr
-
- do oldRes <- readItr itr itrResponse id
- newRes <- unsafeIOToSTM $ completeUnconditionalHeaders $ fromJust oldRes
- writeItr itr itrResponse $ Just newRes
+postprocess ∷ Interaction → STM ()
+postprocess (Interaction {..})
+ = do res ← readTVar itrResponse
+ let sc = resStatus res
+
+ unless (any (\ p → p sc) [isSuccessful, isRedirection, isError])
+ $ abortSTM InternalServerError []
+ $ Just
+ $ A.toText
+ $ A.fromAsciiBuilder
+ $ A.toAsciiBuilder "The status code is not good for a final status of a response: "
+ ⊕ printStatusCode sc
+
+ when (sc ≡ MethodNotAllowed ∧ getHeader "Allow" res ≡ Nothing)
+ $ abortSTM InternalServerError []
+ $ Just
+ $ A.toText
+ $ A.fromAsciiBuilder
+ $ A.toAsciiBuilder "The status was "
+ ⊕ printStatusCode sc
+ ⊕ A.toAsciiBuilder " but no Allow header."
+
+ when (sc ≢ NotModified ∧ isRedirection sc ∧ getHeader "Location" res ≡ Nothing)
+ $ abortSTM InternalServerError []
+ $ Just
+ $ A.toText
+ $ A.fromAsciiBuilder
+ $ A.toAsciiBuilder "The status code was "
+ ⊕ printStatusCode sc
+ ⊕ A.toAsciiBuilder " but no Location header."
+
+ case itrRequest of
+ Just req → postprocessWithRequest sc req
+ Nothing → return ()
+
+ -- itrResponse の内容は relyOnRequest によって變へられてゐる可
+ -- 能性が高い。
+ do oldRes ← readTVar itrResponse
+ newRes ← unsafeIOToSTM
+ $ completeUnconditionalHeaders itrConfig oldRes
+ writeTVar itrResponse newRes
where
- relyOnRequest itr
- = do status <- readItr itr itrResponse (resStatus . fromJust)
-
- let req = fromJust $ itrRequest itr
- reqVer = reqVersion req
- canHaveBody = if reqMethod req == HEAD then
+ postprocessWithRequest ∷ StatusCode → Request → STM ()
+ postprocessWithRequest sc (Request {..})
+ = do let canHaveBody = if reqMethod ≡ HEAD then
False
else
- not (isInformational status ||
- status == NoContent ||
- status == ResetContent ||
- status == NotModified )
+ (¬) (isInformational sc ∨
+ sc ≡ NoContent ∨
+ sc ≡ ResetContent ∨
+ sc ≡ NotModified )
+
+ updateRes $ deleteHeader "Content-Length"
+ updateRes $ deleteHeader "Transfer-Encoding"
- updateRes itr $ deleteHeader "Content-Length"
+ cType ← readHeader "Content-Type"
+ when (cType ≡ Nothing)
+ $ updateRes $ setHeader "Content-Type" defaultPageContentType
if canHaveBody then
- do teM <- readHeader itr "Transfer-Encoding"
- if reqVer == HttpVersion 1 1 then
-
- do case teM of
- Nothing -> updateRes itr $ setHeader "Transfer-Encoding" "chunked"
- Just te -> let teList = [trim isWhiteSpace x
- | x <- splitBy (== ',') (map toLower te)]
- in
- when (teList == [] || last teList /= "chunked")
- $ setStatus itr InternalServerError
-
- writeItr itr itrWillChunkBody True
- else
- case fmap (map toLower) teM of
- Nothing -> return ()
- Just "identity" -> return ()
- _ -> setStatus itr InternalServerError
-
- cType <- readHeader itr "Content-Type"
- when (cType == Nothing)
- $ updateRes itr $ setHeader "Content-Type" "application/octet-stream"
- else
+ when (reqVersion ≡ HttpVersion 1 1)
+ $ do updateRes $ setHeader "Transfer-Encoding" "chunked"
+ writeTVar itrWillChunkBody True
+ else
-- body 関連のヘッダを削除。但し HEAD なら Content-* は殘す
- do updateRes itr $ deleteHeader "Transfer-Encoding"
- when (reqMethod req /= HEAD)
- $ updateRes itr $ deleteHeader "Content-Type"
-
- conn <- readHeader itr "Connection"
- case fmap (map toLower) conn of
- Just "close" -> writeItr itr itrWillClose True
- _ -> updateRes itr $ setHeader "Connection" "close"
-
- when (reqMethod req == HEAD || not canHaveBody)
- $ writeTVar (itrWillDiscardBody itr) True
-
- setStatus :: Interaction -> StatusCode -> STM ()
- setStatus itr status
- = writeTVar (itrResponse itr) (Just $ Response {
- resVersion = HttpVersion 1 1
- , resStatus = status
- , resHeaders = []
- })
-
- readHeader :: Interaction -> String -> STM (Maybe String)
- readHeader itr name
- = do valueMM <- readItrF itr itrResponse $ getHeader name
- case valueMM of
- Just (Just val) -> return $ Just val
- _ -> return Nothing
-
- updateRes :: Interaction -> (Response -> Response) -> STM ()
- updateRes itr updator
- = updateItrF itr itrResponse updator
-
-
-completeUnconditionalHeaders :: Response -> IO Response
-completeUnconditionalHeaders res
- = return res >>= compServer >>= compDate >>= return
+ when (reqMethod ≢ HEAD)
+ $ do updateRes $ deleteHeader "Content-Type"
+ updateRes $ deleteHeader "Etag"
+ updateRes $ deleteHeader "Last-Modified"
+
+ conn ← readCIHeader "Connection"
+ case conn of
+ Nothing → return ()
+ Just value → when (value ≡ "close")
+ $ writeTVar itrWillClose True
+
+ willClose ← readTVar itrWillClose
+ when willClose
+ $ updateRes $ setHeader "Connection" "close"
+
+ when (reqMethod ≡ HEAD ∨ not canHaveBody)
+ $ writeTVar itrWillDiscardBody True
+
+ readHeader ∷ CIAscii → STM (Maybe Ascii)
+ {-# INLINE readHeader #-}
+ readHeader k = getHeader k <$> readTVar itrResponse
+
+ readCIHeader ∷ CIAscii → STM (Maybe CIAscii)
+ {-# INLINE readCIHeader #-}
+ readCIHeader k = getCIHeader k <$> readTVar itrResponse
+
+ updateRes ∷ (Response → Response) → STM ()
+ {-# INLINE updateRes #-}
+ updateRes f
+ = do old ← readTVar itrResponse
+ writeTVar itrResponse (f old)
+
+completeUnconditionalHeaders ∷ Config → Response → IO Response
+completeUnconditionalHeaders conf = (compDate =≪) ∘ compServer
where
- compServer res
- = case getHeader "Server" res of
- Nothing -> return $ addHeader "Server" "Lucu/1.0" res
- Just _ -> return res
-
- compDate res
- = case getHeader "Date" res of
- Nothing -> do time <- getClockTime
- return $ addHeader "Date" (formatHTTPDateTime time) res
- Just _ -> return res
\ No newline at end of file
+ compServer res'
+ = case getHeader "Server" res' of
+ Nothing → return $ setHeader "Server" (cnfServerSoftware conf) res'
+ Just _ → return res'
+
+ compDate res'
+ = case getHeader "Date" res' of
+ Nothing → do date ← getCurrentDate
+ return $ setHeader "Date" date res'
+ Just _ → return res'
+
+getCurrentDate ∷ IO Ascii
+getCurrentDate = HTTP.toAscii <$> getCurrentTime