- setStatus itr status
- = updateItr itr itrResponse
- $ \ res -> res {
- resStatus = status
- }
-
- preprocessHeader itr (name, value)
- = case map toLower name of
-
- "expect"
- -> if value `noCaseEq` "100-continue" then
- writeItr itr itrExpectedContinue True
- else
- setStatus itr ExpectationFailed
-
- "transfer-encoding"
- -> case map toLower value of
- "identity" -> return ()
- "chunked" -> writeItr itr itrRequestIsChunked True
- _ -> setStatus itr NotImplemented
-
- "content-length"
- -> if all isDigit value then
- do let len = read value
- writeItr itr itrReqChunkLength $ Just len
- writeItr itr itrReqChunkRemaining $ Just len
- else
- setStatus itr BadRequest
-
- "connection"
- -> case map toLower value of
- "close" -> writeItr itr itrWillClose True
- _ -> return ()
-
- _ -> return ()
\ No newline at end of file
+ initialAR ∷ AugmentedRequest
+ initialAR = AugmentedRequest {
+ arRequest = req
+ , arInitialStatus = fromStatusCode OK
+ , arWillChunkBody = False
+ , arWillDiscardBody = False
+ , arWillClose = False
+ , arExpectedContinue = False
+ , arReqBodyLength = Nothing
+ }
+ go ∷ State AugmentedRequest ()
+ go = do examineHttpVersion
+ examineMethod
+ examineAuthority localHost localPort
+ examineHeaders
+ examineBodyLength
+
+setRequest ∷ Request → State AugmentedRequest ()
+setRequest req
+ = modify $ \ar → ar { arRequest = req }
+
+setStatus ∷ StatusCode sc ⇒ sc → State AugmentedRequest ()
+setStatus sc
+ = modify $ \ar → ar { arInitialStatus = fromStatusCode sc }
+
+setWillClose ∷ Bool → State AugmentedRequest ()
+setWillClose b
+ = modify $ \ar → ar { arWillClose = b }
+
+setBodyLength ∷ Maybe RequestBodyLength → State AugmentedRequest ()
+setBodyLength len
+ = modify $ \ar → ar { arReqBodyLength = len }
+
+examineHttpVersion ∷ State AugmentedRequest ()
+examineHttpVersion
+ = do req ← gets arRequest
+ case reqVersion req of
+ -- HTTP/1.0 requests can't Keep-Alive.
+ HttpVersion 1 0
+ → setWillClose True
+ HttpVersion 1 1
+ → modify $ \ar → ar { arWillChunkBody = True }
+ _ → do setStatus HTTPVersionNotSupported
+ setWillClose True
+
+examineMethod ∷ State AugmentedRequest ()
+examineMethod
+ = do req ← gets arRequest
+ case reqMethod req of
+ GET → return ()
+ HEAD → modify $ \ar → ar { arWillDiscardBody = True }
+ POST → return ()
+ PUT → return ()
+ DELETE → return ()
+ _ → setStatus NotImplemented
+
+examineAuthority ∷ CI Text → PortNumber → State AugmentedRequest ()
+examineAuthority localHost localPort
+ = do req ← gets arRequest
+ when (isNothing $ uriAuthority $ reqURI req) $
+ case reqVersion req of
+ -- HTTP/1.0 requests have no Host header so complete it
+ -- with the configuration value.
+ HttpVersion 1 0
+ → let host = localHost
+ port = case localPort of
+ 80 → ""
+ n → A.unsafeFromString $ ':':show n
+ req' = updateAuthority host port req
+ in
+ setRequest req'
+ -- HTTP/1.1 requests MUST have a Host header.
+ HttpVersion 1 1
+ → case getHeader "Host" req of
+ Just str
+ → let (host, port)
+ = parseHost str
+ req' = updateAuthority host port req
+ in
+ setRequest req'
+ Nothing
+ → setStatus BadRequest
+ -- Should never reach here...
+ ver → fail ("internal error: unknown version: " ⧺ show ver)
+
+parseHost ∷ Ascii → (CI Text, Ascii)
+parseHost hp
+ = let (h, p) = C8.break (≡ ':') $ A.toByteString hp
+ -- FIXME: should decode punycode here.
+ hText = CI.mk $ T.decodeUtf8 h
+ pAscii = A.unsafeFromByteString p
+ in
+ (hText, pAscii)
+
+updateAuthority ∷ CI Text → Ascii → Request → Request
+updateAuthority host port req
+ = let uri = reqURI req
+ uri' = uri {
+ uriAuthority = Just URIAuth {
+ uriUserInfo = ""
+ , uriRegName = T.unpack $ CI.original host
+ , uriPort = A.toString port
+ }
+ }
+ in
+ req { reqURI = uri' }
+
+examineHeaders ∷ State AugmentedRequest ()
+examineHeaders
+ = do req ← gets arRequest
+
+ case getCIHeader "Expect" req of
+ Nothing → return ()
+ Just v
+ | v ≡ "100-continue"
+ → modify $ \ar → ar { arExpectedContinue = True }
+ | otherwise
+ → setStatus ExpectationFailed
+
+ case getCIHeader "Transfer-Encoding" req of
+ Nothing → return ()
+ Just v
+ | v ≡ "identity"
+ → return ()
+ | v ≡ "chunked"
+ → setBodyLength $ Just Chunked
+ | otherwise
+ → setStatus NotImplemented
+
+ case A.toByteString <$> getHeader "Content-Length" req of
+ Nothing → return ()
+ Just value → case C8.readInt value of
+ Just (len, garbage)
+ | C8.null garbage ∧ len ≥ 0
+ → setBodyLength $ Just $ Fixed len
+ _ → setStatus BadRequest
+
+ case getCIHeader "Connection" req of
+ Just v
+ | v ≡ "close"
+ → setWillClose True
+ _ → return ()
+
+examineBodyLength ∷ State AugmentedRequest ()
+examineBodyLength
+ = do req ← gets arRequest
+ len ← gets arReqBodyLength
+ if reqMustHaveBody req then
+ -- POST and PUT requests must have an entity body.
+ when (isNothing len)
+ $ setStatus LengthRequired
+ else
+ -- Other requests must NOT have an entity body.
+ when (isJust len)
+ $ setStatus BadRequest