----------------------------------------------------------------------------- -- | -- Module : Network.Browser -- Copyright : (c) Warrick Gray 2002 -- License : BSD -- -- Maintainer : bjorn@bringert.net -- Stability : experimental -- Portability : non-portable (not tested) -- -- An HTTP\/1.1 compatible wrapper for the HTTP module. ----------------------------------------------------------------------------- {- Change Log: - altered 'closeTCP' to 'close', for consistency with altered HTTP - added debugging settings to browser. To Do: - testing!!! - remove BrowserAction type? Possibly replace with IORef? - (more todo's in the HTTP mod) -} module Network.Browser ( BrowserState, BrowserAction, -- browser monad, effectively a state monad. Cookie, Form(..), Proxy(..), browse, -- BrowserAction a -> IO a request, -- Request -> BrowserAction Response setAllowRedirects, getAllowRedirects, Authority(..), getAuthorities, setAuthorities, addAuthority, getAuthorityGen, setAuthorityGen, setAllowBasicAuth, setCookieFilter, defaultCookieFilter, userCookieFilter, getCookies, setCookies, addCookie, setErrHandler, setOutHandler, setProxy, setDebugLog, out, err, ioAction, -- :: IO a -> BrowserAction a defaultGETRequest, formToRequest, uriDefaultTo, uriTrimHost ) where import Network.HTTP import Data.Char (toLower,isAlphaNum,isSpace) import Data.List (isPrefixOf,isSuffixOf,elemIndex,elemIndices) import Data.Maybe import Control.Monad (foldM,filterM,liftM,when) import Text.ParserCombinators.Parsec import Network.URI import qualified System.IO import Data.Word (Word8) import qualified Network.HTTP.MD5 as MD5 import qualified Network.HTTP.Base64 as Base64 type Octet = Word8 ------------------------------------------------------------------ ----------------------- Miscellaneous ---------------------------- ------------------------------------------------------------------ word, quotedstring :: Parser String quotedstring = do { char '"' ; str <- many (satisfy $ not . (=='"')) ; char '"' ; return str } word = many1 (satisfy (\x -> isAlphaNum x || x=='_' || x=='.' || x=='-' || x==':')) -- misc string fns trim :: String -> String trim = let dropspace = dropWhile isSpace in reverse . dropspace . reverse . dropspace -- | Splits a list into two parts, the delimiter occurs -- at the head of the second list. Nothing is returned -- when no occurance of the delimiter is found. split :: Eq a => a -> [a] -> Maybe ([a],[a]) split delim list = case delim `elemIndex` list of Nothing -> Nothing Just x -> Just $ splitAt x list -- | Removes delimiters. splitMany :: Eq a => a -> [a] -> [[a]] splitMany delim str = fn str ixs where ixs = elemIndices delim str fn _ [] = [] fn ls (h:t) = let (a,b) = splitAt h ls in a : fn b t -- | Returns a URI that is consistent with the first -- argument uri when read in the context of a second. -- If second argument is not sufficient context for -- determining a full URI then anarchy reins. uriDefaultTo :: URI -> URI -> URI uriDefaultTo a b = case a `relativeTo` b of Nothing -> a Just x -> x uriTrimHost :: URI -> URI uriTrimHost uri = uri { uriScheme="", uriAuthority=Nothing } ------------------------------------------------------------------ ----------------------- Cookie Stuff ----------------------------- ------------------------------------------------------------------ -- Some conventions: -- assume ckDomain is lowercase -- data Cookie = MkCookie { ckDomain , ckName , ckValue :: String , ckPath , ckComment , ckVersion :: Maybe String } deriving(Show,Read) instance Eq Cookie where a == b = ckDomain a == ckDomain b && ckName a == ckName b && ckPath a == ckPath b defaultCookieFilter :: URI -> Cookie -> IO Bool defaultCookieFilter url cky = return True userCookieFilter :: URI -> Cookie -> IO Bool userCookieFilter url cky = do putStrLn ("Set-Cookie received when requesting: " ++ show url) case ckComment cky of Nothing -> return () Just x -> putStrLn ("Cookie Comment:\n" ++ x) putStrLn ("Domain/Path: " ++ ckDomain cky ++ case ckPath cky of Nothing -> "" Just x -> "/" ++ x) putStrLn (ckName cky ++ '=' : ckValue cky) System.IO.hSetBuffering System.IO.stdout System.IO.NoBuffering System.IO.hSetBuffering System.IO.stdin System.IO.NoBuffering System.IO.hPutStr System.IO.stdout "Accept [y/n]? " x <- System.IO.hGetChar System.IO.stdin System.IO.hSetBuffering System.IO.stdin System.IO.LineBuffering System.IO.hSetBuffering System.IO.stdout System.IO.LineBuffering return (toLower x == 'y') -- | Serialise a Cookie for inclusion in a request. cookieToHeader :: Cookie -> Header cookieToHeader ck = Header HdrCookie text where text = "$Version=" ++ fromMaybe "0" (ckVersion ck) ++ ';' : ckName ck ++ "=" ++ ckValue ck ++ (case ckPath ck of Nothing -> "" Just x -> ";$Path=" ++ x) ++ ";$Domain=" ++ ckDomain ck {- replace "error" call with [] in final version? -} headerToCookies :: String -> Header -> [Cookie] headerToCookies dom (Header HdrSetCookie val) = case parse cookies "" val of Left e -> error ("Cookie parse failure on: " ++ val ++ " " ++ show e) Right x -> x where cookies :: Parser [Cookie] cookies = sepBy1 cookie (char ',') cookie :: Parser Cookie cookie = do { name <- word ; spaces ; char '=' ; spaces ; val <- cvalue ; args <- cdetail ; return $ mkCookie name val args } cvalue :: Parser String spaces = many (satisfy isSpace) cvalue = quotedstring <|> many1 (satisfy $ not . (==';')) -- all keys in the result list MUST be in lower case cdetail :: Parser [(String,String)] cdetail = many $ try (do { spaces ; char ';' ; spaces ; s1 <- word ; spaces ; s2 <- option "" (do { char '=' ; spaces ; v <- cvalue ; return v }) ; return (map toLower s1,s2) }) mkCookie :: String -> String -> [(String,String)] -> Cookie mkCookie nm val more = MkCookie { ckName=nm , ckValue=val , ckDomain=map toLower (fromMaybe dom (lookup "domain" more)) , ckPath=lookup "path" more , ckVersion=lookup "version" more , ckComment=lookup "comment" more } -- | Adds a cookie to the browser state, removing duplicates. addCookie :: Cookie -> BrowserAction () addCookie c = alterBS (\b -> b { bsCookies=c : fn (bsCookies b) }) where fn = filter (not . (==c)) setCookies :: [Cookie] -> BrowserAction () setCookies cs = alterBS (\b -> b { bsCookies=cs }) getCookies :: BrowserAction [Cookie] getCookies = getBS bsCookies -- ...get domain specific cookies... -- ... this needs changing for consistency with rfc2109... -- ... currently too broad. getCookiesFor :: String -> String -> BrowserAction [Cookie] getCookiesFor dom path = do cks <- getCookies return (filter cookiematch cks) where cookiematch :: Cookie -> Bool cookiematch ck = ckDomain ck `isSuffixOf` dom && case ckPath ck of Nothing -> True Just p -> p `isPrefixOf` path setCookieFilter :: (URI -> Cookie -> IO Bool) -> BrowserAction () setCookieFilter f = alterBS (\b -> b { bsCookieFilter=f }) getCookieFilter :: BrowserAction (URI -> Cookie -> IO Bool) getCookieFilter = getBS bsCookieFilter ------------------------------------------------------------------ ----------------------- Authorisation Stuff ---------------------- ------------------------------------------------------------------ {- The browser handles 401 responses in the following manner: 1) extract all WWW-Authenticate headers from a 401 response 2) rewrite each as a Challenge object, using "headerToChallenge" 3) pick a challenge to respond to, usually the strongest challenge understood by the client, using "pickChallenge" 4) generate a username/password combination using the browsers "bsAuthorityGen" function (the default behaviour is to ask the user) 5) build an Authority object based upon the challenge and user data, store this new Authority in the browser state 6) convert the Authority to a request header and add this to a request using "withAuthority" 7) send the amended request Note that by default requests are annotated with authority headers before the first sending, based upon previously generated Authority objects (which contain domain information). Once a specific authority is added to a rejected request this predictive annotation is suppressed. 407 responses are handled in a similar manner, except a) Authorities are not collected, only a single proxy authority is kept by the browser b) If the proxy used by the browser (type Proxy) is NoProxy, then a 407 response will generate output on the "err" stream and the response will be returned. Notes: - digest authentication so far ignores qop, so fails to authenticate properly with qop=auth-int challenges - calculates a1 more than necessary - doesn't reverse authenticate - doesn't properly receive AuthenticationInfo headers, so fails to use next-nonce etc -} data Algorithm = AlgMD5 | AlgMD5sess deriving(Eq) instance Show Algorithm where show AlgMD5 = "md5" show AlgMD5sess = "md5-sess" data Qop = QopAuth | QopAuthInt deriving(Eq,Show) data Challenge = ChalBasic { chRealm :: String } | ChalDigest { chRealm :: String , chDomain :: [URI] , chNonce :: String , chOpaque :: Maybe String , chStale :: Bool , chAlgorithm ::Maybe Algorithm , chQop :: [Qop] } -- | Convert WWW-Authenticate header into a Challenge object headerToChallenge :: URI -> Header -> Maybe Challenge headerToChallenge baseURI (Header _ str) = case parse challenge "" str of Left e -> Nothing Right (name,props) -> case name of "basic" -> mkBasic props "digest" -> mkDigest props _ -> Nothing where challenge :: Parser (String,[(String,String)]) challenge = do { nme <- word ; spaces ; pps <- cprops ; return (map toLower nme,pps) } cprops = sepBy1 cprop comma comma = do { spaces ; char ',' ; spaces } cprop = do { nm <- word ; char '=' ; val <- quotedstring ; return (map toLower nm,val) } quotedstring = do { char '"' ; str <- many (satisfy (not.(=='"'))) ; char '"' ; return str } mkBasic, mkDigest :: [(String,String)] -> Maybe Challenge mkBasic params = fmap ChalBasic (lookup "realm" params) mkDigest params = -- with Maybe monad do { r <- lookup "realm" params ; n <- lookup "nonce" params ; return $ ChalDigest { chRealm = r , chDomain = (annotateURIs $ map parseURI $ words $ fromMaybe [] $ lookup "domain" params) , chNonce = n , chOpaque = lookup "opaque" params , chStale = "true" == (map toLower $ fromMaybe "" (lookup "stale" params)) , chAlgorithm= readAlgorithm (fromMaybe "MD5" $ lookup "algorithm" params) , chQop = readQop (fromMaybe "" $ lookup "qop" params) } } annotateURIs :: [Maybe URI] -> [URI] annotateURIs = (map (\u -> fromMaybe u (u `relativeTo` baseURI))) . catMaybes -- Change These: readQop :: String -> [Qop] readQop = catMaybes . (map strToQop) . (splitMany ',') strToQop str = case map toLower (trim str) of "auth" -> Just QopAuth "auth-int" -> Just QopAuthInt _ -> Nothing readAlgorithm str = case map toLower (trim str) of "md5" -> Just AlgMD5 "md5-sess" -> Just AlgMD5sess _ -> Nothing data Authority = AuthBasic { auRealm :: String , auUsername :: String , auPassword :: String , auSite :: URI } | AuthDigest { auRealm :: String , auUsername :: String , auPassword :: String , auNonce :: String , auAlgorithm :: Maybe Algorithm , auDomain :: [URI] , auOpaque :: Maybe String , auQop :: [Qop] } -- | Return authorities for a given domain and path. -- Assumes "dom" is lower case getAuthFor :: String -> String -> BrowserAction [Authority] getAuthFor dom pth = do { list <- getAuthorities ; return (filter match list) } where match :: Authority -> Bool match (AuthBasic _ _ _ s) = matchURI s match (AuthDigest _ _ _ _ _ ds _ _) = or (map matchURI ds) matchURI :: URI -> Bool matchURI s = (uriToAuthorityString s == dom) && (uriPath s `isPrefixOf` pth) -- | Interacting with browser state: getAuthorities :: BrowserAction [Authority] getAuthorities = getBS bsAuthorities setAuthorities :: [Authority] -> BrowserAction () setAuthorities as = alterBS (\b -> b { bsAuthorities=as }) addAuthority :: Authority -> BrowserAction () addAuthority a = alterBS (\b -> b { bsAuthorities=a:bsAuthorities b }) getAuthorityGen :: BrowserAction (URI -> String -> IO (Maybe (String,String))) getAuthorityGen = getBS bsAuthorityGen setAuthorityGen :: (URI -> String -> IO (Maybe (String,String))) -> BrowserAction () setAuthorityGen f = alterBS (\b -> b { bsAuthorityGen=f }) setAllowBasicAuth :: Bool -> BrowserAction () setAllowBasicAuth ba = alterBS (\b -> b { bsAllowBasicAuth=ba }) -- TO BE CHANGED!!! pickChallenge :: [Challenge] -> Maybe Challenge pickChallenge = listToMaybe -- | Retrieve a likely looking authority for a Request. anticipateChallenge :: Request -> BrowserAction (Maybe Authority) anticipateChallenge rq = let uri = rqURI rq in do { authlist <- getAuthFor (uriToAuthorityString uri) (uriPath uri) ; return (listToMaybe authlist) } -- | Asking the user to respond to a challenge challengeToAuthority :: URI -> Challenge -> BrowserAction (Maybe Authority) challengeToAuthority uri ch = -- prompt user for authority if answerable ch then do { prompt <- getAuthorityGen ; userdetails <- ioAction $ prompt uri (chRealm ch) ; case userdetails of Nothing -> return Nothing Just (u,p) -> return (Just $ buildAuth ch u p) } else return Nothing where answerable :: Challenge -> Bool answerable (ChalBasic _) = True answerable ch = (chAlgorithm ch) == Just AlgMD5 buildAuth :: Challenge -> String -> String -> Authority buildAuth (ChalBasic r) u p = AuthBasic { auSite=uri , auRealm=r , auUsername=u , auPassword=p } -- note to self: this is a pretty stupid operation -- to perform isn't it? ChalX and AuthX are so very -- similar. buildAuth (ChalDigest r d n o s a q) u p = AuthDigest { auRealm=r , auUsername=u , auPassword=p , auDomain=d , auNonce=n , auOpaque=o , auAlgorithm=a , auQop=q } -- | Generating a credentials value from an Authority, in -- the context of a specific request. If a client nonce -- was to be used then this function might need to -- be of type ... -> BrowserAction String withAuthority :: Authority -> Request -> String withAuthority a rq = case a of AuthBasic _ _ user pass -> "Basic " ++ base64encode (auUsername a ++ ':' : auPassword a) AuthDigest _ _ _ _ _ _ _ _ -> "Digest username=\"" ++ auUsername a ++ "\",realm=\"" ++ auRealm a ++ "\",nonce=\"" ++ auNonce a ++ "\",uri=\"" ++ digesturi ++ ",response=\"" ++ rspdigest ++ "\"" -- plus optional stuff: ++ ( if isJust (auAlgorithm a) then "" else ",algorithm=\"" ++ show (fromJust $ auAlgorithm a) ++ "\"" ) ++ ( if isJust (auOpaque a) then "" else ",opaque=\"" ++ (fromJust $ auOpaque a) ++ "\"" ) ++ ( if null (auQop a) then "" else ",qop=auth" ) where rspdigest = "\"" ++ map toLower (kd (md5 a1) (noncevalue ++ ":" ++ md5 a2)) ++ "\"" -- FIXME: these probably only work right for latin-1 strings stringToOctets :: String -> [Octet] stringToOctets = map (fromIntegral . fromEnum) octetsToString :: [Octet] -> String octetsToString = map (toEnum . fromIntegral) base64encode :: String -> String base64encode = Base64.encode . stringToOctets md5 :: String -> String md5 = octetsToString . MD5.hash . stringToOctets kd :: String -> String -> String kd a b = md5 (a ++ ":" ++ b) a1, a2 :: String a1 = auUsername a ++ ":" ++ auRealm a ++ ":" ++ auPassword a {- If the "qop" directive's value is "auth" or is unspecified, then A2 is: A2 = Method ":" digest-uri-value If the "qop" value is "auth-int", then A2 is: A2 = Method ":" digest-uri-value ":" H(entity-body) -} a2 = show (rqMethod rq) ++ ":" ++ digesturi digesturi = show (rqURI rq) noncevalue = auNonce a ------------------------------------------------------------------ ------------------ Proxy Stuff ----------------------------------- ------------------------------------------------------------------ -- | Specifies if a proxy should be used for the request. data Proxy = NoProxy -- ^ Don't use a proxy. | Proxy String (Maybe Authority) -- ^ Use the proxy given. Should be of the form "http:\/\/host:port", "host", "host:port", or "http:\/\/host" ------------------------------------------------------------------ ------------------ Browser State Actions ------------------------- ------------------------------------------------------------------ data BrowserState = BS { bsErr, bsOut :: String -> IO () , bsCookies :: [Cookie] , bsCookieFilter :: URI -> Cookie -> IO Bool , bsAuthorityGen :: URI -> String -> IO (Maybe (String,String)) , bsAuthorities :: [Authority] , bsAllowRedirects :: Bool , bsAllowBasicAuth :: Bool , bsConnectionPool :: [Connection] , bsProxy :: Proxy , bsDebug :: Maybe String } instance Show BrowserState where show bs = "BrowserState { " ++ show (bsCookies bs) ++ "\n" {- ++ show (bsAuthorities bs) ++ "\n"-} ++ "AllowRedirects: " ++ show (bsAllowRedirects bs) ++ "} " -- Simple DIY stateful behaviour, with IO data BrowserAction a = BA { lift :: (BrowserState -> IO (BrowserState,a)) } instance Monad BrowserAction where a >>= f = BA (\b -> do { (nb,v) <- lift a b ; lift (f v) nb}) return x = BA (\b -> return (b,x)) instance Functor BrowserAction where fmap f = liftM f -- | Apply a browser action to a state. browse :: BrowserAction a -> IO a browse act = do x <- lift act defaultBrowserState return (snd x) where defaultBrowserState :: BrowserState defaultBrowserState = BS { bsErr = putStrLn , bsOut = putStrLn , bsCookies = [] , bsCookieFilter = defaultCookieFilter , bsAuthorityGen = (error "bsAuthGen wanted") , bsAuthorities = [] , bsAllowRedirects = True , bsAllowBasicAuth = False , bsConnectionPool = [] , bsProxy = NoProxy , bsDebug = Nothing } -- | Alter browser state alterBS :: (BrowserState -> BrowserState) -> BrowserAction () alterBS f = BA (\b -> return (f b,())) getBS :: (BrowserState -> a) -> BrowserAction a getBS f = BA (\b -> return (b,f b)) -- | Do an io action ioAction :: IO a -> BrowserAction a ioAction a = BA (\b -> a >>= \v -> return (b,v)) -- Stream handlers setErrHandler, setOutHandler :: (String -> IO ()) -> BrowserAction () setErrHandler h = alterBS (\b -> b { bsErr=h }) setOutHandler h = alterBS (\b -> b { bsOut=h }) out, err :: String -> BrowserAction () out s = do { f <- getBS bsOut ; ioAction $ f s } err s = do { f <- getBS bsErr ; ioAction $ f s } -- Redirects setAllowRedirects :: Bool -> BrowserAction () setAllowRedirects bl = alterBS (\b -> b {bsAllowRedirects=bl}) getAllowRedirects :: BrowserAction Bool getAllowRedirects = getBS bsAllowRedirects -- Proxy setProxy :: Proxy -> BrowserAction () setProxy p = alterBS (\b -> b {bsProxy = p}) getProxy :: BrowserAction Proxy getProxy = getBS bsProxy -- Debug setDebugLog :: Maybe String -> BrowserAction () setDebugLog v = alterBS (\b -> b {bsDebug=v}) -- Page control type RequestState = ( Int -- number of 401 responses so far , Int -- number of redirects so far , Int -- number of retrys so far , Bool -- whether to pre-empt 401 response ) -- Surely the most important bit: request :: Request -> BrowserAction (URI,Response) request = request' initialState where initialState = (0,0,0,True) request' :: RequestState -> Request -> BrowserAction (URI,Response) request' (denycount,redirectcount,retrycount,preempt) rq = do -- add cookies to request let uri = rqURI rq cookies <- getCookiesFor (uriToAuthorityString uri) (uriPath uri) when (not $ null cookies) (out $ "Adding cookies to request. Cookie names: " ++ foldl spaceappend "" (map ckName cookies)) -- add credentials to request rq' <- if not preempt then return rq else do { auth <- anticipateChallenge rq ; case auth of Just x -> return (insertHeader HdrAuthorization (withAuthority x rq) rq) Nothing -> return rq } let rq'' = insertHeaders (map cookieToHeader cookies) rq' p <- getProxy out ("Sending:\n" ++ show rq'') e_rsp <- case p of NoProxy -> dorequest (uriAuth $ rqURI rq'') rq'' Proxy str ath -> let rq''' = case ath of Nothing -> rq'' Just x -> insertHeader HdrProxyAuthorization (withAuthority x rq'') rq'' -- Proxy can take multiple forms - look for http://host:port first, -- then host:port. Fall back to just the string given (probably a host name). proxyURIAuth = maybe notURI (\parsed -> maybe notURI id (uriAuthority parsed)) (parseURI str) notURI = -- If the ':' is dropped from port below, dorequest will assume port 80. Leave it! let (host, port) = span (':'/=) str in if null port || null host then URIAuth "" str "" else URIAuth "" host port in do out $ "proxy uri host: " ++ uriRegName proxyURIAuth ++ ", port: " ++ uriPort proxyURIAuth dorequest proxyURIAuth rq''' case e_rsp of Left v -> if (retrycount < 4) && (v == ErrorReset || v == ErrorClosed) then request' (denycount,redirectcount,retrycount+1,preempt) rq else error ("Exception raised in request: " ++ show v) Right rsp -> do out ("Received:\n" ++ show rsp) -- add new cookies to browser state let cookieheaders = retrieveHeaders HdrSetCookie rsp let newcookies = concat (map (headerToCookies $ uriToAuthorityString uri) cookieheaders) when (not $ null newcookies) (out $ foldl (\x y -> x ++ "\n " ++ show y) "Cookies received:" newcookies) filterfn <- getCookieFilter newcookies' <- ioAction (filterM (filterfn uri) newcookies) foldM (\_ -> addCookie) () newcookies' when (not $ null newcookies) (out $ "Accepting cookies with names: " ++ foldl spaceappend "" (map ckName newcookies')) case rspCode rsp of (4,0,1) -> -- Credentials not sent or refused. out "401 - credentials not sent or refused" >> if denycount > 2 then return (uri,rsp) else do { let hdrs = retrieveHeaders HdrWWWAuthenticate rsp ; case pickChallenge (catMaybes $ map (headerToChallenge uri) hdrs) of Just x -> do { au <- challengeToAuthority uri x ; case au of Just au' -> out "Retrying request with new credentials" >> request' (denycount+1,redirectcount,retrycount,False) (insertHeader HdrAuthorization (withAuthority au' rq) rq) Nothing -> return (uri,rsp) {- do nothing -} } Nothing -> return (uri,rsp) {- do nothing -} } (4,0,7) -> -- Proxy Authentication required out "407 - proxy authentication required" >> if denycount > 2 then return (uri,rsp) else do { let hdrs = retrieveHeaders HdrProxyAuthenticate rsp ; case pickChallenge (catMaybes $ map (headerToChallenge uri) hdrs) of Just x -> do { au <- challengeToAuthority uri x ; case au of Just au' -> do { pxy <- getBS bsProxy ; case pxy of NoProxy -> do { err "Proxy authentication required without proxy!" ; return (uri,rsp) } Proxy x y -> do { out "Retrying with proxy authentication" ; setProxy (Proxy x $ Just au') ; request' (denycount+1,redirectcount,retrycount,False) rq } } Nothing -> return (uri,rsp) {- do nothing -} } Nothing -> return (uri,rsp) {- do nothing -} } (3,0,3) -> -- Redirect using GET request method. do { out "303 - redirect using GET" ; rd <- getAllowRedirects ; if not rd || redirectcount > 4 then return (uri,rsp) else case retrieveHeaders HdrLocation rsp of (Header _ u:_) -> case parseURIReference u of Just newuri -> let newuri' = case newuri `relativeTo` uri of Nothing -> newuri Just x -> x in do { out ("Redirecting to " ++ show newuri' ++ " ...") ; let rq = rq { rqMethod=GET, rqURI=newuri', rqBody="" } ; request' (0,redirectcount+1,retrycount,True) (replaceHeader HdrContentLength "0" rq) } Nothing -> do { err ("Parse of Location header in a redirect response failed: " ++ u) ; return (uri,rsp) } [] -> do { err "No Location header in redirect response" ; return (uri,rsp) } } (3,0,5) -> case retrieveHeaders HdrLocation rsp of (Header _ u:_) -> case parseURIReference u of Just newuri -> do { out ("Retrying with proxy " ++ show newuri ++ "...") ; setProxy (Proxy (uriToAuthorityString newuri) Nothing) ; request' (0,0,retrycount+1,True) rq } Nothing -> do { err ("Parse of Location header in a proxy redirect response failed: " ++ u) ; return (uri,rsp) } [] -> do { err "No Location header in proxy redirect response." ; return (uri,rsp) } (3,_,_) -> redirect uri rsp _ -> return (uri,rsp) where spaceappend :: String -> String -> String spaceappend x y = x ++ ' ' : y redirect uri rsp = do rd <- getAllowRedirects if not rd || redirectcount > 4 then return (uri,rsp) else do case retrieveHeaders HdrLocation rsp of (Header _ u:_) -> case parseURIReference u of Just newuri -> do let newuri' = case newuri `relativeTo` uri of Nothing -> newuri Just x -> x out ("Redirecting to " ++ show newuri' ++ " ...") request' (0,redirectcount+1,retrycount,True) (rq { rqURI=newuri' }) Nothing -> do err ("Parse of Location header in a redirect response failed: " ++ u) return (uri,rsp) [] -> do err "No Location header in redirect response." return (uri,rsp) dorequest :: URIAuth -> Request -> BrowserAction (Either ConnError Response) dorequest hst rqst = do { pool <- getBS bsConnectionPool ; conn <- ioAction $ filterM (\c -> c `isConnectedTo` uriAuthToString hst) pool ; rsp <- case conn of [] -> do { out ("Creating new connection to " ++ uriAuthToString hst) ; let port = case uriPort hst of (':':s) -> read s _ -> 80 ; c <- ioAction $ openTCPPort (uriRegName hst) port ; let pool' = if length pool > 5 then init pool else pool ; when (length pool > 5) (ioAction $ close (last pool)) ; alterBS (\b -> b { bsConnectionPool=c:pool' }) ; dorequest2 hst c rqst } (c:_) -> do { out ("Recovering connection to " ++ uriAuthToString hst) ; dorequest2 hst c rqst } ; ; return rsp } dorequest2 hst c r = do { dbg <- getBS bsDebug ; ioAction $ case dbg of Nothing -> sendHTTP c r Just f -> debugStream (f++'-': uriAuthToString hst) c >>= \c' -> sendHTTP c' r } uriAuth x = case uriAuthority x of Just ua -> ua _ -> error ("No uri authority for: "++show x) uriAuthToString :: URIAuth -> String uriAuthToString URIAuth { uriUserInfo = uinfo , uriRegName = regname , uriPort = port } = ((if null uinfo then id else (uinfo++)) . (regname++) . (port++)) "" -- This function duplicates old Network.URI.authority behaviour. uriToAuthorityString :: URI -> String uriToAuthorityString u = maybe "" uriAuthToString (uriAuthority u) ------------------------------------------------------------------ ------------------ Request Building ------------------------------ ------------------------------------------------------------------ libUA = "haskell-libwww/0.1" defaultGETRequest :: URI -> Request defaultGETRequest uri = Request { rqURI=uri , rqBody="" , rqHeaders=[ Header HdrContentLength "0" , Header HdrUserAgent libUA ] , rqMethod=GET } -- This form junk is completely untested... type FormVar = (String,String) data Form = Form RequestMethod URI [FormVar] formToRequest :: Form -> Request formToRequest (Form m u vs) = let enc = urlEncodeVars vs in case m of GET -> Request { rqMethod=GET , rqHeaders=[ Header HdrContentLength "0" ] , rqBody="" , rqURI=u { uriQuery= '?' : enc } -- What about old query? } POST -> Request { rqMethod=POST , rqHeaders=[ Header HdrContentType "application/x-www-form-urlencoded", Header HdrContentLength (show $ length enc) ] , rqBody=enc , rqURI=u }