Resolve todos

servant-server/src/Servant/Server/Internal.hs

@@ -28,10 +28,11 @@ import           Control.Monad.Trans.Resource (runResourceT)
 import qualified Data.ByteString            as B
 import qualified Data.ByteString.Char8      as BC8
 import qualified Data.ByteString.Lazy       as BL
+import           Data.Maybe                 (fromMaybe, mapMaybe)
 import           Data.Either                (partitionEithers)
-import           Data.Maybe                 (fromMaybe)
 import           Data.String                (fromString)
 import           Data.String.Conversions    (cs, (<>))
+import qualified Data.Text                  as T
 import           Data.Typeable
 import           GHC.TypeLits               (KnownNat, KnownSymbol, natVal,
                                              symbolVal)
@@ -319,10 +320,9 @@ instance (KnownSymbol sym, FromHttpApiData a, HasServer api context)
             Just Nothing  -> return Nothing -- param present with no value -> Nothing
             Just (Just v) ->
               case parseQueryParam v of
-                  -- TODO: This should set an error description (including
+                  Left e -> delayedFailFatal err400
-                  -- paramname)
+                      { errBody = cs $ "Error parsing query parameter " <> paramname <> " failed: " <> e
-                  Left _e -> delayedFailFatal err400 -- parsing the request
+                      }
-                                                     -- paramter failed
 
                   Right param -> return $ Just param
         delayed = addParameterCheck subserver . withRequest $ \req ->
@@ -356,26 +356,25 @@ instance (KnownSymbol sym, FromHttpApiData a, HasServer api context)
   type ServerT (QueryParams sym a :> api) m =
     [a] -> ServerT api m
 
-  route Proxy context subserver =
+  route Proxy context subserver = route (Proxy :: Proxy api) context $
-    let querytext r = parseQueryText $ rawQueryString r
+      subserver `addParameterCheck` withRequest paramsCheck
-        -- if sym is "foo", we look for query string parameters
+    where
-        -- named "foo" or "foo[]" and call parseQueryParam on the
+      paramname = cs $ symbolVal (Proxy :: Proxy sym)
-        -- corresponding values
+      paramsCheck req =
-        parameters r = filter looksLikeParam (querytext r)
+          case partitionEithers $ fmap parseQueryParam params of
-        parseParam (paramName, paramTxt) =
+              ([], parsed) -> return parsed
-          case parseQueryParam (fromMaybe "" paramTxt) of
+              (errs, _)    -> delayedFailFatal err400
-              Left _e -> Left paramName -- On error, remember name of parameter
+                  { errBody = cs $ "Error parsing query parameter(s) " <> paramname <> " failed: " <> T.intercalate ", " errs
-              Right paramVal -> Right paramVal
+                  }
-        parseParams req =
+        where
-          case partitionEithers $ parseParam <$> parameters req of
+          params :: [T.Text]
-              ([], params) -> return params -- No errors
+          params = mapMaybe snd
-              -- TODO: This should set an error description
+                 . filter (looksLikeParam . fst)
-              (_errors, _) -> delayedFailFatal err400
+                 . parseQueryText
-        delayed = addParameterCheck subserver . withRequest $ \req ->
+                 . rawQueryString
-                    parseParams req
+                 $ req
-    in  route (Proxy :: Proxy api) context delayed
+
-    where paramname = cs $ symbolVal (Proxy :: Proxy sym)
+          looksLikeParam name = name == paramname || name == (paramname <> "[]")
-          looksLikeParam (name, _) = name == paramname || name == (paramname <> "[]")
 
 -- | If you use @'QueryFlag' "published"@ in one of the endpoints for your API,
 -- this automatically requires your server-side handler to be a function
@@ -457,22 +456,28 @@ instance ( AllCTUnrender list a, HasServer api context
   type ServerT (ReqBody list a :> api) m =
     a -> ServerT api m
 
-  route Proxy context subserver =
+  route Proxy context subserver
-    route (Proxy :: Proxy api) context (addBodyCheck subserver bodyCheck)
+      = route (Proxy :: Proxy api) context $
+          addBodyCheck subserver ctCheck bodyCheck
     where
-      bodyCheck = withRequest $ \ request -> do
+      -- Content-Type check, we only lookup we can try to parse the request body
+      ctCheck = withRequest $ \ request -> do
         -- See HTTP RFC 2616, section 7.2.1
         -- http://www.w3.org/Protocols/rfc2616/rfc2616-sec7.html#sec7.2.1
         -- See also "W3C Internet Media Type registration, consistency of use"
         -- http://www.w3.org/2001/tag/2002/0129-mime
         let contentTypeH = fromMaybe "application/octet-stream"
                          $ lookup hContentType $ requestHeaders request
-        mrqbody <- handleCTypeH (Proxy :: Proxy list) (cs contentTypeH)
+        case canHandleCTypeH (Proxy :: Proxy list) (cs contentTypeH) :: Maybe (BL.ByteString -> Either String a) of
-               <$> liftIO (lazyRequestBody request)
+          Nothing -> delayedFailFatal err415
+          Just f  -> return f
+
+      -- Body check, we get a body parsing functions as the first argument.
+      bodyCheck f = withRequest $ \ request -> do
+        mrqbody <- f <$> liftIO (lazyRequestBody request)
         case mrqbody of
-          Nothing        -> delayedFailFatal err415
+          Left e  -> delayedFailFatal err400 { errBody = cs e }
-          Just (Left e)  -> delayedFailFatal err400 { errBody = cs e }
+          Right v -> return v
-          Just (Right v) -> return v
 
 -- | Make sure the incoming request starts with @"/path"@, strip it and
 -- pass the rest of the request path to @api@.

servant-server/src/Servant/Server/Internal/RoutingApplication.hs

@@ -132,14 +132,14 @@ toApplication ra request respond = ra request routingRespond
 -- 405 (bad method)
 -- 401 (unauthorized)
 -- 415 (unsupported media type)
--- 400 (bad request)
 -- 406 (not acceptable)
+-- 400 (bad request)
 -- @
 --
 -- Therefore, while routing, we delay most checks so that they
 -- will ultimately occur in the right order.
 --
--- A 'Delayed' contains four delayed blocks of tests, and
+-- A 'Delayed' contains many delayed blocks of tests, and
 -- the actual handler:
 --
 -- 1. Delayed captures. These can actually cause 404, and
@@ -148,24 +148,28 @@ toApplication ra request respond = ra request routingRespond
 -- check order from the error reporting, see above). Delayed
 -- captures can provide inputs to the actual handler.
 --
--- 2. Query parameter checks. They require parsing and can cause 400 if the
+-- 2. Method check(s). This can cause a 405. On success,
--- parsing fails. Query parameter checks provide inputs to the handler
---
--- 3. Method check(s). This can cause a 405. On success,
 -- it does not provide an input for the handler. Method checks
 -- are comparatively cheap.
 --
--- 4. Body and accept header checks. The request body check can
+-- 3. Authentication checks. This can cause 401.
--- cause both 400 and 415. This provides an input to the handler.
+--
--- The accept header check can be performed as the final
+-- 4. Accept and content type header checks. These checks
--- computation in this block. It can cause a 406.
+-- can cause 415 and 406 errors.
+--
+-- 5. Query parameter checks. They require parsing and can cause 400 if the
+-- parsing fails. Query parameter checks provide inputs to the handler
+--
+-- 6. Body check. The request body check can cause 400.
 --
 data Delayed env c where
   Delayed :: { capturesD :: env -> DelayedIO captures
-             , paramsD   :: DelayedIO params
              , methodD   :: DelayedIO ()
              , authD     :: DelayedIO auth
-             , bodyD     :: DelayedIO body
+             , acceptD   :: DelayedIO ()
+             , contentD  :: DelayedIO contentType
+             , paramsD   :: DelayedIO params
+             , bodyD     :: contentType -> DelayedIO body
              , serverD   :: captures
                          -> params
                          -> auth
@@ -209,7 +213,7 @@ runDelayedIO m req = transResourceT runRouteResultT $ runReaderT (runDelayedIO'
 -- | A 'Delayed' without any stored checks.
 emptyDelayed :: RouteResult a -> Delayed env a
 emptyDelayed result =
-  Delayed (const r) r r r r (\ _ _ _ _ _ -> result)
+  Delayed (const r) r r r r r (const r) (\ _ _ _ _ _ -> result)
   where
     r = return ()
 
@@ -270,20 +274,25 @@ addAuthCheck Delayed{..} new =
     , ..
     } -- Note [Existential Record Update]
 
--- | Add a body check to the end of the body block.
+-- | Add a content type and body checks around parameter checks.
+--
+-- We'll report failed content type check (415), before trying to parse
+-- query parameters (400). Which, in turn, happens before request body parsing.
 addBodyCheck :: Delayed env (a -> b)
-             -> DelayedIO a
+             -> DelayedIO c         -- ^ content type check
+             -> (c -> DelayedIO a)  -- ^ body check
              -> Delayed env b
-addBodyCheck Delayed{..} new =
+addBodyCheck Delayed{..} newContentD newBodyD =
   Delayed
-    { bodyD    = (,) <$> bodyD <*> new
+    { contentD = (,) <$> contentD <*> newContentD
+    , bodyD    = \(content, c) -> (,) <$> bodyD content <*> newBodyD c
     , serverD  = \ c p a (z, v) req -> ($ v) <$> serverD c p a z req
     , ..
     } -- Note [Existential Record Update]
 
 
--- | Add an accept header check to the beginning of the body
+-- | Add an accept header check before handling parameters.
--- block. There is a tradeoff here. In principle, we'd like
+-- In principle, we'd like
 -- to take a bad body (400) response take precedence over a
 -- failed accept check (406). BUT to allow streaming the body,
 -- we cannot run the body check and then still backtrack.
@@ -297,7 +306,7 @@ addAcceptCheck :: Delayed env a
                -> Delayed env a
 addAcceptCheck Delayed{..} new =
   Delayed
-    { bodyD = new *> bodyD
+    { acceptD = acceptD *> new
     , ..
     } -- Note [Existential Record Update]
 
@@ -322,12 +331,14 @@ runDelayed :: Delayed env a
            -> Request
            -> ResourceT IO (RouteResult a)
 runDelayed Delayed{..} env = runDelayedIO $ do
+    r <- ask
     c <- capturesD env
     methodD
     a <- authD
-    b <- bodyD
+    acceptD
-    r <- ask
+    content <- contentD
-    p <- paramsD -- Has to be after body to respect the relative error order
+    p <- paramsD       -- Has to be before body parsing, but after content-type checks
+    b <- bodyD content
     liftRouteResult (serverD c p a b r)
 
 -- | Runs a delayed server and the resulting action.

servant-server/test/Servant/Server/ErrorSpec.hs

@@ -6,6 +6,7 @@
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 module Servant.Server.ErrorSpec (spec) where
 
+import           Control.Monad              (when)
 import           Data.Aeson                 (encode)
 import qualified Data.ByteString.Char8      as BC
 import qualified Data.ByteString.Lazy.Char8 as BCL
@@ -114,10 +115,19 @@ errorOrderSpec =
       `shouldRespondWith` 415
 
   it "has 400 as its sixth highest priority error" $ do
-    request goodMethod badParams [goodAuth, goodContentType, goodAccept] goodBody
+    badParamsRes <- request goodMethod badParams [goodAuth, goodContentType, goodAccept] goodBody
-      `shouldRespondWith` 400
+    badBodyRes <- request goodMethod goodUrl [goodAuth, goodContentType, goodAccept] badBody
-    request goodMethod goodUrl [goodAuth, goodContentType, goodAccept] badBody
+
-      `shouldRespondWith` 400
+    -- Both bad body and bad params result in 400
+    return badParamsRes `shouldRespondWith` 400
+    return badBodyRes `shouldRespondWith` 400
+
+    -- Param check should occur before body checks
+    both <- request goodMethod badParams [goodAuth, goodContentType, goodAccept ] badBody
+    when (both /= badParamsRes) $ liftIO $
+        expectationFailure $ "badParams + badBody /= badParams: " ++ show both ++ ", " ++ show badParamsRes
+    when (both == badBodyRes) $ liftIO $
+        expectationFailure $ "badParams + badBody == badBody: " ++ show both
 
   it "has handler-level errors as last priority" $ do
     request goodMethod goodUrl [goodAuth, goodContentType, goodAccept] goodBody

servant-server/test/Servant/Server/Internal/RoutingApplicationSpec.hs

@@ -19,6 +19,7 @@ import Data.Proxy
 import GHC.TypeLits (Symbol, KnownSymbol, symbolVal)
 import Servant
 import Servant.Server.Internal.RoutingApplication
+import Network.Wai (defaultRequest)
 import Test.Hspec
 import Test.Hspec.Wai (request, shouldRespondWith, with)
 
@@ -56,12 +57,14 @@ freeTestResource = modifyIORef delayedTestRef $ \r -> case r of
 
 delayed :: DelayedIO () -> RouteResult (Handler ()) -> Delayed () (Handler ())
 delayed body srv = Delayed
-  { capturesD = \_ -> return ()
+  { capturesD = \() -> return ()
   , methodD   = return ()
   , authD     = return ()
+  , acceptD   = return ()
+  , contentD  = return ()
   , paramsD   = return ()
-  , bodyD     = do
+  , bodyD     = \() -> do
-      liftIO (writeTestResource"hia" >> putStrLn "garbage created")
+      liftIO (writeTestResource "hia" >> putStrLn "garbage created")
       _ <- register (freeTestResource >> putStrLn "garbage collected")
       body
   , serverD   = \() () () _body _req -> srv
@@ -70,7 +73,7 @@ delayed body srv = Delayed
 simpleRun :: Delayed () (Handler ())
           -> IO ()
 simpleRun d = fmap (either ignoreE id) . try $
-  runAction d () undefined (\_ -> return ()) (\_ -> FailFatal err500)
+  runAction d () defaultRequest (\_ -> return ()) (\_ -> FailFatal err500)
 
   where ignoreE :: SomeException -> ()
         ignoreE = const ()
@@ -85,10 +88,10 @@ data Res (sym :: Symbol)
 instance (KnownSymbol sym, HasServer api ctx) => HasServer (Res sym :> api) ctx where
     type ServerT (Res sym :> api) m = IORef (TestResource String) -> ServerT api m
     route Proxy ctx server = route (Proxy :: Proxy api) ctx $
-        server `addBodyCheck` check
+        addBodyCheck server (return ()) check
       where
         sym  = symbolVal (Proxy :: Proxy sym)
-        check = do
+        check () = do
             liftIO $ writeTestResource sym
             _ <- register freeTestResource
             return delayedTestRef

servant/src/Servant/API/ContentTypes.hs

@@ -220,14 +220,20 @@ class Accept ctype => MimeUnrender ctype a where
     {-# MINIMAL mimeUnrender | mimeUnrenderWithType #-}
 
 class AllCTUnrender (list :: [*]) a where
+    canHandleCTypeH
+        :: Proxy list
+        -> ByteString  -- Content-Type header
+        -> Maybe (ByteString -> Either String a)
+
     handleCTypeH :: Proxy list
                  -> ByteString     -- Content-Type header
                  -> ByteString     -- Request body
                  -> Maybe (Either String a)
+    handleCTypeH p ctypeH body = ($ body) `fmap` canHandleCTypeH p ctypeH
 
 instance ( AllMimeUnrender ctyps a ) => AllCTUnrender ctyps a where
-    handleCTypeH _ ctypeH body = M.mapContentMedia lkup (cs ctypeH)
+    canHandleCTypeH p ctypeH =
-      where lkup = allMimeUnrender (Proxy :: Proxy ctyps) body
+        M.mapContentMedia (allMimeUnrender p) (cs ctypeH)
 
 --------------------------------------------------------------------------
 -- * Utils (Internal)
@@ -292,20 +298,19 @@ instance OVERLAPPING_
 --------------------------------------------------------------------------
 class (AllMime list) => AllMimeUnrender (list :: [*]) a where
     allMimeUnrender :: Proxy list
-                    -> ByteString
+                    -> [(M.MediaType, ByteString -> Either String a)]
-                    -> [(M.MediaType, Either String a)]
 
 instance AllMimeUnrender '[] a where
-    allMimeUnrender _ _ = []
+    allMimeUnrender _ = []
 
 instance ( MimeUnrender ctyp a
          , AllMimeUnrender ctyps a
          ) => AllMimeUnrender (ctyp ': ctyps) a where
-    allMimeUnrender _ bs =
+    allMimeUnrender _ =
         (map mk $ NE.toList $ contentTypes pctyp)
-        ++ allMimeUnrender pctyps bs
+        ++ allMimeUnrender pctyps
       where
-        mk ct   = (ct, mimeUnrenderWithType pctyp ct bs)
+        mk ct   = (ct, \bs -> mimeUnrenderWithType pctyp ct bs)
         pctyp  = Proxy :: Proxy ctyp
         pctyps = Proxy :: Proxy ctyps