module Network.Wai.Application.Classic.CGI (
cgiApp
) where
import Control.Exception (SomeException, IOException, try)
import Control.Exception.Lifted (catch)
import Control.Monad (when)
import Control.Monad.IO.Class (liftIO)
import Control.Monad.Trans.Resource
import Data.ByteString (ByteString)
import qualified Data.ByteString as BS hiding (unpack)
import qualified Data.ByteString.Char8 as BS (readInt, unpack)
import Data.Conduit
import qualified Data.Conduit.Binary as CB
import qualified Data.Conduit.List as CL
import Network.HTTP.Types
import Network.Wai
import Network.Wai.Application.Classic.Conduit
import Network.Wai.Application.Classic.Field
import Network.Wai.Application.Classic.Header
import Network.Wai.Application.Classic.Path
import Network.Wai.Application.Classic.Types
import Network.Wai.Logger.Utils
import Prelude hiding (catch)
import System.Environment
import System.IO
import System.Process
type ENVVARS = [(String,String)]
gatewayInterface :: String
gatewayInterface = "CGI/1.1"
cgiApp :: ClassicAppSpec -> CgiAppSpec -> CgiRoute -> Application
cgiApp cspec spec cgii req = case method of
Right GET -> cgiApp' False cspec spec cgii req
Right POST -> cgiApp' True cspec spec cgii req
_ -> return $ responseLBS methodNotAllowed405 textPlainHeader "Method Not Allowed\r\n"
where
method = parseMethod $ requestMethod req
cgiApp' :: Bool -> ClassicAppSpec -> CgiAppSpec -> CgiRoute -> Application
cgiApp' body cspec spec cgii req = do
(rhdl,whdl,tellEOF) <- liftIO (execProcess cspec spec cgii req) >>= register3
when body $ toCGI whdl req
tellEOF
fromCGI rhdl cspec req
where
register3 (rhdl,whdl,pid) = do
_ <- register $ terminateProcess pid
_ <- register $ hClose rhdl
keyw <- register $ hClose whdl
return (rhdl,whdl,release keyw)
type TRYPATH = Either IOException String
toCGI :: Handle -> Request -> ResourceT IO ()
toCGI whdl req = requestBody req $$ CB.sinkHandle whdl
fromCGI :: Handle -> ClassicAppSpec -> Application
fromCGI rhdl cspec req = do
(src', hs) <- cgiHeader `catch` recover
let (st, hdr, hasBody) = case check hs of
Nothing -> (internalServerError500,[],False)
Just (s,h) -> (s,h,True)
hdr' = addServer cspec hdr
liftIO $ logger cspec req st Nothing
let src = if hasBody then src' else CL.sourceNull
return $ ResponseSource st hdr' src
where
check hs = lookup hContentType hs >> case lookup hStatus hs of
Nothing -> Just (ok200, hs)
Just l -> toStatus l >>= \s -> Just (s,hs')
where
hs' = filter (\(k,_) -> k /= hStatus) hs
toStatus s = BS.readInt s >>= \x -> Just (Status (fst x) s)
emptyHeader = []
recover (_ :: SomeException) = return (CL.sourceNull, emptyHeader)
cgiHeader = do
(rsrc,hs) <- CB.sourceHandle rhdl $$+ parseHeader
src <- toResponseSource rsrc
return (src,hs)
execProcess :: ClassicAppSpec -> CgiAppSpec -> CgiRoute -> Request -> IO (Handle, Handle, ProcessHandle)
execProcess cspec spec cgii req = do
let naddr = showSockAddr . remoteHost $ req
epath <- try (getEnv "PATH") :: IO TRYPATH
(Just whdl,Just rhdl,_,pid) <- createProcess $ proSpec naddr epath
hSetEncoding rhdl latin1
hSetEncoding whdl latin1
return (rhdl, whdl, pid)
where
proSpec naddr epath = CreateProcess {
cmdspec = RawCommand prog []
, cwd = Nothing
, env = Just $ makeEnv req naddr scriptName pathinfo (softwareName cspec) epath
, std_in = CreatePipe
, std_out = CreatePipe
, std_err = Inherit
, close_fds = True
#if __GLASGOW_HASKELL__ >= 702
, create_group = True
#endif
}
(prog, scriptName, pathinfo) =
pathinfoToCGI (cgiSrc cgii)
(cgiDst cgii)
(fromByteString (rawPathInfo req))
(indexCgi spec)
makeEnv :: Request -> NumericAddress -> String -> String -> ByteString ->
TRYPATH -> ENVVARS
makeEnv req naddr scriptName pathinfo sname epath = addPath epath . addLen . addType . addCookie $ baseEnv
where
baseEnv = [
("GATEWAY_INTERFACE", gatewayInterface)
, ("SCRIPT_NAME", scriptName)
, ("REQUEST_METHOD", BS.unpack . requestMethod $ req)
, ("SERVER_NAME", BS.unpack . serverName $ req)
, ("SERVER_PORT", show . serverPort $ req)
, ("REMOTE_ADDR", naddr)
, ("SERVER_PROTOCOL", show . httpVersion $ req)
, ("SERVER_SOFTWARE", BS.unpack sname)
, ("PATH_INFO", pathinfo)
, ("QUERY_STRING", query req)
]
headers = requestHeaders req
addLen = addEnv "CONTENT_LENGTH" $ lookup hContentLength headers
addType = addEnv "CONTENT_TYPE" $ lookup hContentType headers
addCookie = addEnv "HTTP_COOKIE" $ lookup hCookie headers
addPath (Left _) ev = ev
addPath (Right path) ev = ("PATH", path) : ev
query = BS.unpack . safeTail . rawQueryString
where
safeTail "" = ""
safeTail bs = BS.tail bs
addEnv :: String -> Maybe ByteString -> ENVVARS -> ENVVARS
addEnv _ Nothing envs = envs
addEnv key (Just val) envs = (key,BS.unpack val) : envs
pathinfoToCGI :: Path -> Path -> Path -> Path -> (FilePath, String, String)
pathinfoToCGI src dst path index = (prog, scriptName, pathinfo)
where
path' = path <\> src
(prog',pathinfo')
| src == path = (index, "")
| otherwise = breakAtSeparator path'
prog = pathString (dst </> prog')
scriptName = pathString (src </> prog')
pathinfo = pathString pathinfo'