+{-# LANGUAGE
+ GeneralizedNewtypeDeriving
+ , DoAndIfThenElse
+ , OverloadedStrings
+ , RecordWildCards
+ , UnicodeSyntax
+ #-}
+-- |This is the Resource Monad; monadic actions to define the behavior
+-- of each resources. The 'Resource' Monad is a kind of 'Prelude.IO'
+-- Monad thus it implements 'Control.Monad.Trans.MonadIO' class. It is
+-- also a state machine.
+--
+-- Request Processing Flow:
+--
+-- 1. A client issues an HTTP request.
+--
+-- 2. If the URI of it matches to any resource, the corresponding
+-- 'Resource' Monad starts running on a newly spawned thread.
+--
+-- 3. The 'Resource' Monad looks at the request header, find (or not
+-- find) an entity, receive the request body (if any), decide the
+-- response header, and decide the response body. This process
+-- will be discussed later.
+--
+-- 4. The 'Resource' Monad and its thread stops running. The client
+-- may or may not be sending us the next request at this point.
+--
+-- 'Resource' Monad takes the following states. The initial state is
+-- /Examining Request/ and the final state is /Done/.
+--
+-- [/Examining Request/] In this state, a 'Resource' looks at the
+-- request header and thinks about an entity for it. If there is a
+-- suitable entity, the 'Resource' tells the system an entity tag
+-- and its last modification time ('foundEntity'). If it found no
+-- entity, it tells the system so ('foundNoEntity'). In case it is
+-- impossible to decide the existence of entity, which is a typical
+-- case for POST requests, 'Resource' does nothing in this state.
+--
+-- [/Getting Body/] A 'Resource' asks the system to receive a
+-- request body from client. Before actually reading from the
+-- socket, the system sends \"100 Continue\" to the client if need
+-- be. When a 'Resource' transits to the next state without
+-- receiving all or part of request body, the system still reads it
+-- and just throws it away.
+--
+-- [/Deciding Header/] A 'Resource' makes a decision of status code
+-- and response header. When it transits to the next state, the
+-- system checks the validness of response header and then write
+-- them to the socket.
+--
+-- [/Deciding Body/] In this state, a 'Resource' asks the system to
+-- write some response body to the socket. When it transits to the
+-- next state without writing any response body, the system
+-- completes it depending on the status code.
+--
+-- [/Done/] Everything is over. A 'Resource' can do nothing for the
+-- HTTP interaction anymore.
+--
+-- Note that the state transition is one-way: for instance, it is an
+-- error to try to read a request body after writing some
+-- response. This limitation is for efficiency. We don't want to read
+-- the entire request before starting 'Resource', nor we don't want to
+-- postpone writing the entire response till the end of 'Resource'
+-- computation.
module Network.HTTP.Lucu.Resource
- ( ResourceDef(..)
- , Resource
- , ResTree
- , mkResTree -- [ ([String], ResourceDef) ] -> ResTree
- , findResource -- ResTree -> URI -> Maybe ResourceDef
- , runResource -- ResourceDef -> Interaction -> IO ThreadId
+ (
+ -- * Types
+ Resource
+ , FormData(..)
+
+ -- * Getting request header
+ -- |These actions can be computed regardless of the current state,
+ -- and they don't change the state.
+ , getConfig
+ , getRemoteAddr
+ , getRemoteAddr'
+ , getRemoteHost
+ , getRemoteCertificate
+ , getRequest
+ , getMethod
+ , getRequestURI
+ , getRequestVersion
+ , getResourcePath
+ , getPathInfo
+ , getQueryForm
+ , getHeader
+ , getAccept
+ , getAcceptEncoding
+ , isEncodingAcceptable
+ , getContentType
+ , getAuthorization
+
+ -- * Finding an entity
+ -- |These actions can be computed only in the /Examining Request/
+ -- state. After the computation, the 'Resource' transits to
+ -- /Getting Body/ state.
+ , foundEntity
+ , foundETag
+ , foundTimeStamp
+ , foundNoEntity
+
+ -- * Getting a request body
+ -- |Computation of these actions changes the state to /Getting
+ -- Body/.
+ , getChunk
+ , getChunks
+ , getForm
+ , defaultLimit
+
+ -- * Setting response headers
+ -- |Computation of these actions changes the state to /Deciding
+ -- Header/.
+ , setStatus
+ , redirect
+ , setContentType
+ , setContentEncoding
+ , setWWWAuthenticate
+
+ -- ** Less frequently used functions
+ , setLocation
+ , setHeader
+ , deleteHeader
+
+ -- * Writing a response body
+ -- |Computation of these actions changes the state to /Deciding
+ -- Body/.
+ , putChunk
+ , putChunks
+ , putBuilder
)
where
-
-import Control.Concurrent
-import Control.Monad.Reader
-import qualified Data.ByteString.Lazy.Char8 as B
-import Data.ByteString.Lazy.Char8 (ByteString)
-import Data.List
+import Blaze.ByteString.Builder (Builder)
+import qualified Blaze.ByteString.Builder.ByteString as BB
+import Control.Applicative
+import Control.Concurrent.STM
+import Control.Monad
+import Control.Monad.IO.Class
+import Control.Monad.Unicode
+import Data.Ascii (Ascii, CIAscii)
+import qualified Data.Ascii as A
+import qualified Data.Attoparsec.Char8 as P
+import qualified Data.Attoparsec.Lazy as LP
+import Data.ByteString (ByteString)
+import qualified Data.ByteString as Strict
+import qualified Data.ByteString.Lazy as Lazy
+import Data.Foldable (toList)
+import Data.List
import qualified Data.Map as M
-import Data.Map (Map)
-import Network.HTTP.Lucu.Interaction
-import Network.HTTP.Lucu.Utils
-import Network.URI
+import Data.Maybe
+import Data.Monoid.Unicode
+import Data.Sequence (Seq)
+import Data.Text (Text)
+import qualified Data.Text as T
+import qualified Data.Text.Encoding as T
+import Data.Time
+import qualified Data.Time.HTTP as HTTP
+import Network.HTTP.Lucu.Abortion
+import Network.HTTP.Lucu.Authorization
+import Network.HTTP.Lucu.Config
+import Network.HTTP.Lucu.ContentCoding
+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.MultipartForm
+import Network.HTTP.Lucu.Postprocess
+import Network.HTTP.Lucu.Request
+import Network.HTTP.Lucu.Resource.Internal
+import Network.HTTP.Lucu.Response
+import Network.HTTP.Lucu.MIMEType
+import Network.HTTP.Lucu.Utils
+import Network.Socket hiding (accept)
+import Network.URI hiding (path)
+import OpenSSL.X509
+import Prelude.Unicode
+
+-- |Get the 'Config' value which is used for the httpd.
+getConfig ∷ Resource Config
+getConfig = itrConfig <$> getInteraction
+
+-- |Get the 'SockAddr' of the remote host. If you want a string
+-- representation instead of 'SockAddr', use 'getRemoteAddr''.
+getRemoteAddr ∷ Resource SockAddr
+getRemoteAddr = itrRemoteAddr <$> getInteraction
+-- |Get the string representation of the address of remote host. If
+-- you want a 'SockAddr' instead of 'String', use 'getRemoteAddr'.
+getRemoteAddr' ∷ Resource HostName
+getRemoteAddr'
+ = do sa ← getRemoteAddr
+ (Just a, _) ← liftIO $ getNameInfo [NI_NUMERICHOST] True False sa
+ return a
-type Resource a = ReaderT Interaction IO a
+-- |Resolve an address to the remote host.
+getRemoteHost ∷ Resource (Maybe HostName)
+getRemoteHost
+ = do sa ← getRemoteAddr
+ fst <$> (liftIO $ getNameInfo [] True False sa)
+-- | Return the X.509 certificate of the client, or 'Nothing' if:
+--
+-- * This request didn't came through an SSL stream.
+--
+-- * The client didn't send us its certificate.
+--
+-- * The 'OpenSSL.Session.VerificationMode' of
+-- 'OpenSSL.Session.SSLContext' in 'SSLConfig' has not been set to
+-- 'OpenSSL.Session.VerifyPeer'.
+getRemoteCertificate ∷ Resource (Maybe X509)
+getRemoteCertificate = itrRemoteCert <$> getInteraction
-{- /aaa/bbb/ccc にアクセスされた時、もし /aaa/bbb に貪欲なリソースがあ
- れば、假に /aaa/bbb/ccc に何らかのリソースがあったとしても必ず
- /aaa/bbb が撰ばれる。/aaa/bbb のリソースが貪欲でなければ、それは無視
- される。 -}
-data ResourceDef = ResourceDef {
- resUsesNativeThread :: Bool
- , resIsGreedy :: Bool
- , resResource :: Resource ()
- }
-type ResTree = ResNode -- root だから Map ではない
-type ResSubtree = Map String ResNode
-data ResNode = ResNode (Maybe ResourceDef) ResSubtree
+-- |Get the 'Method' value of the request.
+getMethod ∷ Resource Method
+getMethod = reqMethod <$> getRequest
+-- |Get the URI of the request.
+getRequestURI ∷ Resource URI
+getRequestURI = reqURI <$> getRequest
-mkResTree :: [ ([String], ResourceDef) ] -> ResTree
-mkResTree list = processRoot list
+-- |Get the HTTP version of the request.
+getRequestVersion ∷ Resource HttpVersion
+getRequestVersion = reqVersion <$> getRequest
+
+-- |Get the path of this 'Resource' (to be exact,
+-- 'Network.HTTP.Lucu.Resource.Tree.ResourceDef') in the
+-- 'Network.HTTP.Lucu.Resource.Tree.ResTree'. The result of this
+-- action is the exact path in the tree even when the
+-- 'Network.HTTP.Lucu.Resource.Tree.ResourceDef' is greedy.
+--
+-- Example:
+--
+-- > main = let tree = mkResTree [ (["foo"], resFoo) ]
+-- > in runHttpd defaultConfig tree
+-- >
+-- > resFoo = ResourceDef {
+-- > resIsGreedy = True
+-- > , resGet = Just $ do requestURI <- getRequestURI
+-- > resourcePath <- getResourcePath
+-- > pathInfo <- getPathInfo
+-- > -- uriPath requestURI == "/foo/bar/baz"
+-- > -- resourcePath == ["foo"]
+-- > -- pathInfo == ["bar", "baz"]
+-- > ...
+-- > , ...
+-- > }
+getResourcePath ∷ Resource [Text]
+getResourcePath = (fromJust ∘ itrResourcePath) <$> getInteraction
+
+-- |This is an analogy of CGI PATH_INFO. The result is
+-- URI-unescaped. It is always @[]@ if the
+-- 'Network.HTTP.Lucu.Resource.Tree.ResourceDef' is not greedy. See
+-- 'getResourcePath'.
+--
+-- Note that the returned path is URI-decoded and then UTF-8 decoded.
+getPathInfo ∷ Resource [Text]
+getPathInfo = do rsrcPath ← getResourcePath
+ reqPath ← splitPathInfo <$> getRequestURI
+ -- rsrcPath と reqPath の共通する先頭部分を reqPath か
+ -- ら全部取り除くと、それは PATH_INFO のやうなものにな
+ -- る。rsrcPath は全部一致してゐるに決まってゐる（でな
+ -- ければこの Resource が撰ばれた筈が無い）ので、
+ -- rsrcPath の長さの分だけ削除すれば良い。
+ return $ drop (length rsrcPath) reqPath
+
+-- |Assume the query part of request URI as
+-- application\/x-www-form-urlencoded, and parse it to pairs of
+-- @(name, formData)@. This action doesn't parse the request body. See
+-- 'inputForm'. Field names are decoded in UTF-8.
+getQueryForm ∷ Resource [(Text, FormData)]
+getQueryForm = parse' <$> getRequestURI
where
- processRoot :: [ ([String], ResourceDef) ] -> ResTree
- processRoot list
- = let (roots, nonRoots) = partition (\ (path, _) -> path == []) list
- children = processNonRoot nonRoots
- in
- if null roots then
- -- / にリソースが定義されない。/foo とかにはあるかも。
- ResNode Nothing children
- else
- -- / がある。
- let (_, def) = last roots
- in
- ResNode (Just def) children
-
- processNonRoot :: [ ([String], ResourceDef) ] -> ResSubtree
- processNonRoot list
- = let subtree = M.fromList [(name, node name)
- | name <- childNames]
- childNames = [name | (name:_, _) <- list]
- node name = let defs = [def | (path, def) <- list, path == [name]]
- in
- if null defs then
- -- この位置にリソースが定義されない。
- -- もっと下にはあるかも。
- ResNode Nothing children
- else
- -- この位置にリソースがある。
- ResNode (Just $ last defs) children
- children = processNonRoot [(path, def)
- | (_:path, def) <- list, not (null path)]
- in
- subtree
-
-
-findResource :: ResTree -> URI -> Maybe ResourceDef
-findResource (ResNode rootDefM subtree) uri
- = let pathStr = uriPath uri
- path = [x | x <- splitBy (== '/') pathStr, x /= ""]
- in
- if null path then
- rootDefM
- else
- walkTree subtree path
+ parse' = map toPairWithFormData ∘
+ parseWWWFormURLEncoded ∘
+ fromJust ∘
+ A.fromChars ∘
+ drop 1 ∘
+ uriQuery
+
+toPairWithFormData ∷ (ByteString, ByteString) → (Text, FormData)
+toPairWithFormData (name, value)
+ = let fd = FormData {
+ fdFileName = Nothing
+ , fdContent = Lazy.fromChunks [value]
+ }
+ in (T.decodeUtf8 name, fd)
+
+-- |Get a value of given request header. Comparison of header name is
+-- case-insensitive. Note that this action is not intended to be used
+-- so frequently: there should be actions like 'getContentType' for
+-- every common headers.
+getHeader ∷ CIAscii → Resource (Maybe Ascii)
+getHeader name
+ = H.getHeader name <$> getRequest
+
+-- |Get a list of 'MIMEType' enumerated on header \"Accept\".
+getAccept ∷ Resource [MIMEType]
+getAccept
+ = do acceptM ← getHeader "Accept"
+ case acceptM of
+ Nothing
+ → return []
+ Just accept
+ → case P.parseOnly p (A.toByteString accept) of
+ Right xs → return xs
+ Left _ → abort BadRequest []
+ (Just $ "Unparsable Accept: " ⊕ A.toText accept)
where
- walkTree :: ResSubtree -> [String] -> Maybe ResourceDef
+ p = do xs ← mimeTypeListP
+ P.endOfInput
+ return xs
- walkTree subtree (name:[])
- = case M.lookup name subtree of
- Nothing -> Nothing
- Just (ResNode defM _) -> defM
+-- |Get a list of @(contentCoding, qvalue)@ enumerated on header
+-- \"Accept-Encoding\". The list is sorted in descending order by
+-- qvalue.
+getAcceptEncoding ∷ Resource [(CIAscii, Maybe Double)]
+getAcceptEncoding
+ = do accEncM ← getHeader "Accept-Encoding"
+ case accEncM of
+ Nothing
+ -- HTTP/1.0 には Accept-Encoding が無い場合の規定が無い
+ -- ので安全の爲 identity が指定された事にする。HTTP/1.1
+ -- の場合は何でも受け入れて良い事になってゐるので "*" が
+ -- 指定された事にする。
+ → do ver ← getRequestVersion
+ case ver of
+ HttpVersion 1 0 → return [("identity", Nothing)]
+ HttpVersion 1 1 → return [("*" , Nothing)]
+ _ → abort InternalServerError []
+ (Just "getAcceptEncoding: unknown HTTP version")
+ Just ae
+ → if ae ≡ "" then
+ -- identity のみが許される。
+ return [("identity", Nothing)]
+ else
+ case P.parseOnly p (A.toByteString ae) of
+ Right xs → return $ map toTuple $ reverse $ sort xs
+ Left _ → abort BadRequest []
+ (Just $ "Unparsable Accept-Encoding: " ⊕ A.toText ae)
+ where
+ p = do xs ← acceptEncodingListP
+ P.endOfInput
+ return xs
- walkTree subtree (x:xs)
- = case M.lookup x subtree of
- Nothing -> Nothing
- Just (ResNode defM children) -> case defM of
- Just (ResourceDef { resIsGreedy = True })
- -> defM
- _ -> walkTree children xs
+ toTuple (AcceptEncoding {..})
+ = (aeEncoding, aeQValue)
+-- |Check whether a given content-coding is acceptable.
+isEncodingAcceptable ∷ CIAscii → Resource Bool
+isEncodingAcceptable encoding = any f <$> getAcceptEncoding
+ where
+ f (e, q)
+ = (e ≡ "*" ∨ e ≡ encoding) ∧ q ≢ Just 0
-runResource :: ResourceDef -> Interaction -> IO ThreadId
-runResource def itr = fork $ runReaderT rsrc itr -- FIXME: 例外をcatch
+-- |Get the header \"Content-Type\" as 'MIMEType'.
+getContentType ∷ Resource (Maybe MIMEType)
+getContentType
+ = do cTypeM ← getHeader "Content-Type"
+ case cTypeM of
+ Nothing
+ → return Nothing
+ Just cType
+ → case P.parseOnly p (A.toByteString cType) of
+ Right t → return $ Just t
+ Left _ → abort BadRequest []
+ (Just $ "Unparsable Content-Type: " ⊕ A.toText cType)
where
- fork = if (resUsesNativeThread def)
- then forkOS
- else forkIO
- rsrc = resResource def
\ No newline at end of file
+ p = do t ← mimeTypeP
+ P.endOfInput
+ return t
+
+-- |Get the header \"Authorization\" as 'AuthCredential'.
+getAuthorization ∷ Resource (Maybe AuthCredential)
+getAuthorization
+ = do authM ← getHeader "Authorization"
+ case authM of
+ Nothing
+ → return Nothing
+ Just auth
+ → case P.parseOnly p (A.toByteString auth) of
+ Right ac → return $ Just ac
+ Left _ → return Nothing
+ where
+ p = do ac ← authCredentialP
+ P.endOfInput
+ return ac
+
+
+-- Finding an entity
+
+-- |Tell the system that the 'Resource' found an entity for the
+-- request URI. If this is a GET or HEAD request, a found entity means
+-- a datum to be replied. If this is a PUT or DELETE request, it means
+-- a datum which was stored for the URI until now. It is an error to
+-- compute 'foundEntity' if this is a POST request.
+--
+-- Computation of 'foundEntity' performs \"If-Match\" test or
+-- \"If-None-Match\" test if possible. When those tests fail, the
+-- computation of 'Resource' immediately aborts with status \"412
+-- Precondition Failed\" or \"304 Not Modified\" depending on the
+-- situation.
+--
+-- If this is a GET or HEAD request, 'foundEntity' automatically puts
+-- \"ETag\" and \"Last-Modified\" headers into the response.
+foundEntity ∷ ETag → UTCTime → Resource ()
+foundEntity tag timeStamp
+ = do driftTo ExaminingRequest
+
+ method ← getMethod
+ when (method ≡ GET ∨ method ≡ HEAD)
+ $ setHeader' "Last-Modified" (HTTP.toAscii timeStamp)
+ when (method ≡ POST)
+ $ abort InternalServerError []
+ (Just "Illegal computation of foundEntity for a POST request.")
+ foundETag tag
+
+ driftTo GettingBody
+
+-- |Tell the system that the 'Resource' found an entity for the
+-- request URI. The only difference from 'foundEntity' is that
+-- 'foundETag' doesn't (and can't) put \"Last-Modified\" header into
+-- the response.
+--
+-- This action is not preferred. You should use 'foundEntity' whenever
+-- possible.
+foundETag ∷ ETag → Resource ()
+foundETag tag
+ = do driftTo ExaminingRequest
+
+ method ← getMethod
+ when (method ≡ GET ∨ method ≡ HEAD)
+ $ setHeader' "ETag"
+ $ A.fromAsciiBuilder
+ $ printETag tag
+ when (method ≡ POST)
+ $ abort InternalServerError []
+ (Just "Illegal computation of foundETag for POST request.")
+
+ -- If-Match があればそれを見る。
+ ifMatch ← getHeader "If-Match"
+ case ifMatch of
+ Nothing → return ()
+ Just value → if value ≡ "*" then
+ return ()
+ else
+ case P.parseOnly p (A.toByteString value) of
+ Right tags
+ -- tags の中に一致するものが無ければ
+ -- PreconditionFailed で終了。
+ → when ((¬) (any (≡ tag) tags))
+ $ abort PreconditionFailed []
+ (Just $ "The entity tag doesn't match: " ⊕ A.toText value)
+ Left _
+ → abort BadRequest [] (Just $ "Unparsable If-Match: " ⊕ A.toText value)
+
+ 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 value → if value ≡ "*" then
+ abort statusForNoneMatch [] (Just "The entity tag matches: *")
+ else
+ case P.parseOnly p (A.toByteString value) of
+ Right tags
+ → when (any (≡ tag) tags)
+ $ abort statusForNoneMatch []
+ (Just $ "The entity tag matches: " ⊕ A.toText value)
+ Left _
+ → abort BadRequest []
+ (Just $ "Unparsable If-None-Match: " ⊕ A.toText value)
+
+ driftTo GettingBody
+ where
+ p = do xs ← eTagListP
+ P.endOfInput
+ return xs
+
+-- |Tell the system that the 'Resource' found an entity for the
+-- request URI. The only difference from 'foundEntity' is that
+-- 'foundTimeStamp' performs \"If-Modified-Since\" test or
+-- \"If-Unmodified-Since\" test instead of \"If-Match\" test or
+-- \"If-None-Match\" test. Be aware that any tests based on last
+-- modification time are unsafe because it is possible to mess up such
+-- tests by modifying the entity twice in a second.
+--
+-- This action is not preferred. You should use 'foundEntity' whenever
+-- possible.
+foundTimeStamp ∷ UTCTime → Resource ()
+foundTimeStamp timeStamp
+ = do driftTo ExaminingRequest
+
+ method ← getMethod
+ when (method ≡ GET ∨ method ≡ HEAD)
+ $ setHeader' "Last-Modified" (HTTP.toAscii timeStamp)
+ when (method ≡ POST)
+ $ abort InternalServerError []
+ (Just "Illegal computation of foundTimeStamp for POST request.")
+
+ 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 HTTP.fromAscii str of
+ Right lastTime
+ → when (timeStamp ≤ lastTime)
+ $ abort statusForIfModSince []
+ (Just $ "The entity has not been modified since " ⊕ A.toText str)
+ Left _
+ → 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 HTTP.fromAscii str of
+ Right lastTime
+ → when (timeStamp > lastTime)
+ $ abort PreconditionFailed []
+ (Just $ "The entity has not been modified since " ⊕ A.toText str)
+ Left _
+ → return () -- 不正な時刻は無視
+ Nothing → return ()
+
+ driftTo GettingBody
+
+-- | Computation of @'foundNoEntity' mStr@ tells the system that the
+-- 'Resource' found no entity for the request URI. @mStr@ is an
+-- optional error message to be replied to the client.
+--
+-- If this is a PUT request, 'foundNoEntity' performs \"If-Match\"
+-- test and aborts with status \"412 Precondition Failed\" when it
+-- failed. If this is a GET, HEAD, POST or DELETE request,
+-- 'foundNoEntity' always aborts with status \"404 Not Found\".
+foundNoEntity ∷ Maybe Text → 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
+
+
+-- Getting a request body
+
+-- | Computation of @'input' limit@ attempts to read the request body
+-- up to @limit@ bytes, and then make the 'Resource' transit to
+-- /Deciding Header/ state. When the actual size of body is larger
+-- than @limit@ bytes, computation of 'Resource' immediately aborts
+-- with status \"413 Request Entity Too Large\". When the request has
+-- no body, 'input' returns an empty string.
+--
+-- @limit@ may be less than or equal to zero. In this case, the
+-- default limitation value ('cnfMaxEntityLength') is used. See
+-- 'defaultLimit'.
+--
+-- 'input' returns a 'Lazy.ByteString' but it's not really lazy:
+-- reading from the socket just happens at the computation of 'input',
+-- not at the evaluation of the 'Lazy.ByteString'. The same goes for
+-- 'inputChunk'.
+input ∷ Int → Resource Lazy.ByteString
+input limit
+ = do driftTo GettingBody
+ itr ← getInteraction
+ chunk ← if reqMustHaveBody $ fromJust $ itrRequest itr then
+ askForInput itr
+ else
+ do driftTo DecidingHeader
+ return (∅)
+ return chunk
+ where
+ askForInput ∷ Interaction → Resource Lazy.ByteString
+ askForInput (Interaction {..})
+ = do let confLimit = cnfMaxEntityLength itrConfig
+ actualLimit = if limit ≤ 0 then
+ confLimit
+ else
+ limit
+ when (actualLimit ≤ 0)
+ $ fail ("inputLBS: limit must be positive: " ⧺ show actualLimit)
+ -- Reader にリクエスト
+ liftIO $ atomically
+ $ writeTVar itrReqBodyWanted 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する。
+ chunk ← liftIO $ atomically
+ $ do chunkLen ← readTVar itrReceivedBodyLen
+ chunkIsOver ← readTVar itrReqChunkIsOver
+ if chunkLen < 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。
+ chunk ← seqToLBS <$> readTVar itrReceivedBody
+ writeTVar itrReceivedBody (∅)
+ writeTVar itrReceivedBodyLen 0
+ return chunk
+
+ driftTo DecidingHeader
+ return chunk
+
+ tooLarge ∷ Int → STM ()
+ tooLarge lim = abortSTM RequestEntityTooLarge []
+ (Just $ "Request body must be smaller than "
+ ⊕ T.pack (show lim) ⊕ " bytes.")
+
+seqToLBS ∷ Seq ByteString → Lazy.ByteString
+{-# INLINE seqToLBS #-}
+seqToLBS = Lazy.fromChunks ∘ toList
+
+-- | Computation of @'inputChunk' limit@ attempts to read a part of
+-- request body up to @limit@ bytes. You can read any large request by
+-- repeating computation of this action. When you've read all the
+-- request body, 'inputChunk' returns an empty string and then make
+-- the 'Resource' transit to /Deciding Header/ state.
+--
+-- @limit@ may be less than or equal to zero. In this case, the
+-- default limitation value ('cnfMaxEntityLength') is used. See
+-- 'defaultLimit'.
+--
+-- Note that 'inputChunkLBS' is more efficient than 'inputChunk' so you
+-- should use it whenever possible.
+inputChunk ∷ Int → Resource Lazy.ByteString
+inputChunk limit
+ = do driftTo GettingBody
+ itr ← getInteraction
+ chunk ← if reqMustHaveBody $ fromJust $ itrRequest itr then
+ askForInput itr
+ else
+ do driftTo DecidingHeader
+ return (∅)
+ return chunk
+ where
+ askForInput ∷ Interaction → Resource Lazy.ByteString
+ askForInput (Interaction {..})
+ = do let confLimit = cnfMaxEntityLength itrConfig
+ actualLimit = if limit < 0 then
+ confLimit
+ else
+ limit
+ when (actualLimit ≤ 0)
+ $ fail ("inputChunkLBS: limit must be positive: " ++ show actualLimit)
+ -- Reader にリクエスト
+ liftIO $ atomically
+ $ writeTVar itrReqBodyWanted 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 chunkLen ← readTVar itrReceivedBodyLen
+ -- 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 (chunkLen < actualLimit)
+ $ do chunkIsOver ← readTVar itrReqChunkIsOver
+ unless chunkIsOver
+ $ retry
+ -- 成功
+ chunk ← seqToLBS <$> readTVar itrReceivedBody
+ writeTVar itrReceivedBody (∅)
+ writeTVar itrReceivedBodyLen 0
+ return chunk
+ when (Lazy.null chunk)
+ $ driftTo DecidingHeader
+ return chunk
+
+-- | Computation of @'inputForm' limit@ attempts to read the request
+-- body with 'input' and parse it as
+-- @application\/x-www-form-urlencoded@ or @multipart\/form-data@. If
+-- the request header \"Content-Type\" is neither of them, 'inputForm'
+-- makes 'Resource' abort with status \"415 Unsupported Media
+-- Type\". If the request has no \"Content-Type\", it aborts with
+-- \"400 Bad Request\".
+--
+-- Field names in @multipart\/form-data@ will be precisely decoded in
+-- accordance with RFC 2231. On the other hand,
+-- @application\/x-www-form-urlencoded@ says nothing about the
+-- encoding of field names, so they'll always be decoded in UTF-8.
+inputForm ∷ Int → Resource [(Text, FormData)]
+inputForm limit
+ = do cTypeM ← getContentType
+ case cTypeM of
+ Nothing
+ → abort BadRequest [] (Just "Missing Content-Type")
+ Just (MIMEType "application" "x-www-form-urlencoded" _)
+ → readWWWFormURLEncoded
+ Just (MIMEType "multipart" "form-data" params)
+ → readMultipartFormData params
+ Just cType
+ → abort UnsupportedMediaType []
+ $ Just
+ $ A.toText
+ $ A.fromAsciiBuilder
+ $ A.toAsciiBuilder "Unsupported media type: "
+ ⊕ printMIMEType cType
+ where
+ readWWWFormURLEncoded
+ = (map toPairWithFormData ∘ parseWWWFormURLEncoded)
+ <$>
+ (bsToAscii =≪ input limit)
+
+ bsToAscii bs
+ = case A.fromByteString (Strict.concat (Lazy.toChunks bs)) of
+ Just a → return a
+ Nothing → abort BadRequest [] (Just "Malformed x-www-form-urlencoded")
+
+ readMultipartFormData params
+ = do case M.lookup "boundary" params of
+ Nothing
+ → abort BadRequest [] (Just "Missing boundary of multipart/form-data")
+ Just boundary
+ → do src ← input limit
+ b ← case A.fromText boundary of
+ Just b → return b
+ Nothing → abort BadRequest []
+ (Just $ "Malformed boundary: " ⊕ boundary)
+ case LP.parse (p b) src of
+ LP.Done _ formList
+ → return formList
+ _ → abort BadRequest [] (Just "Unparsable multipart/form-data")
+ where
+ p b = do xs ← multipartFormP b
+ P.endOfInput
+ return xs
+
+-- | This is just a constant @-1@. It's better to say @'input'
+-- 'defaultLimit'@ than to say @'input' (-1)@ but these are exactly
+-- the same.
+defaultLimit ∷ Int
+defaultLimit = (-1)
+
+
+-- Setting response headers
+
+-- | Computation of @'redirect' code uri@ sets the response status to
+-- @code@ and \"Location\" header to @uri@. The @code@ must satisfy
+-- 'isRedirection' or it causes an error.
+redirect ∷ StatusCode → URI → Resource ()
+redirect code uri
+ = do when (code ≡ NotModified ∨ not (isRedirection code))
+ $ abort InternalServerError []
+ $ Just
+ $ A.toText
+ $ A.fromAsciiBuilder
+ $ A.toAsciiBuilder "Attempted to redirect with status "
+ ⊕ printStatusCode code
+ setStatus code
+ setLocation uri
+
+-- | Computation of @'setContentType' mType@ sets the response header
+-- \"Content-Type\" to @mType@.
+setContentType ∷ MIMEType → Resource ()
+setContentType
+ = setHeader "Content-Type" ∘ A.fromAsciiBuilder ∘ printMIMEType
+
+-- | Computation of @'setLocation' uri@ sets the response header
+-- \"Location\" to @uri@. You usually don't need to call this function
+-- directly.
+setLocation ∷ URI → Resource ()
+setLocation uri
+ = case A.fromChars uriStr of
+ Just a → setHeader "Location" a
+ Nothing → abort InternalServerError []
+ (Just $ "Malformed URI: " ⊕ T.pack uriStr)
+ where
+ uriStr = uriToString id uri ""
+
+-- |Computation of @'setContentEncoding' codings@ sets the response
+-- header \"Content-Encoding\" to @codings@.
+setContentEncoding ∷ [CIAscii] → Resource ()
+setContentEncoding codings
+ = do ver ← getRequestVersion
+ tr ← case ver of
+ HttpVersion 1 0 → return (toAB ∘ unnormalizeCoding)
+ HttpVersion 1 1 → return toAB
+ _ → abort InternalServerError []
+ (Just "setContentEncoding: Unknown HTTP version")
+ setHeader "Content-Encoding"
+ (A.fromAsciiBuilder $ joinWith ", " $ map tr codings)
+ where
+ toAB = A.toAsciiBuilder ∘ A.fromCIAscii
+
+-- |Computation of @'setWWWAuthenticate' challenge@ sets the response
+-- header \"WWW-Authenticate\" to @challenge@.
+setWWWAuthenticate ∷ AuthChallenge → Resource ()
+setWWWAuthenticate challenge
+ = setHeader "WWW-Authenticate" (printAuthChallenge challenge)
+
+
+-- Writing a response body
+
+-- | Write a chunk in 'Lazy.ByteString' to the response body. It is
+-- safe to apply this function to an infinitely long
+-- 'Lazy.ByteString'.
+--
+-- Note that you must first set the response header \"Content-Type\"
+-- before applying this function. See: 'setContentType'
+putChunk ∷ Lazy.ByteString → Resource ()
+putChunk = putBuilder ∘ BB.fromLazyByteString
projects / Lucu.git / blobdiff