@@ -1,29 +1,31 @@
1−{-# LANGUAGE CPP #-}
1+{-# LANGUAGE AllowAmbiguousTypes #-}
2{-# LANGUAGE ConstraintKinds #-}
2{-# LANGUAGE ConstraintKinds #-}
3{-# LANGUAGE DataKinds #-}
4{-# LANGUAGE DataKinds #-}
4{-# LANGUAGE DeriveDataTypeable #-}
5{-# LANGUAGE DeriveDataTypeable #-}
5{-# LANGUAGE FlexibleContexts #-}
6{-# LANGUAGE FlexibleContexts #-}
6{-# LANGUAGE FlexibleInstances #-}
7{-# LANGUAGE FlexibleInstances #-}
8+{-# LANGUAGE InstanceSigs #-}
9+{-# LANGUAGE LambdaCase #-}
7{-# LANGUAGE MultiParamTypeClasses #-}
10{-# LANGUAGE MultiParamTypeClasses #-}
8{-# LANGUAGE OverloadedStrings #-}
11{-# LANGUAGE OverloadedStrings #-}
9{-# LANGUAGE PolyKinds #-}
12{-# LANGUAGE PolyKinds #-}
13+{-# LANGUAGE QuantifiedConstraints #-}
10{-# LANGUAGE RankNTypes #-}
14{-# LANGUAGE RankNTypes #-}
11{-# LANGUAGE ScopedTypeVariables #-}
15{-# LANGUAGE ScopedTypeVariables #-}
12{-# LANGUAGE TupleSections #-}
16{-# LANGUAGE TupleSections #-}
17+{-# LANGUAGE TypeApplications #-}
13{-# LANGUAGE TypeFamilies #-}
18{-# LANGUAGE TypeFamilies #-}
14{-# LANGUAGE TypeOperators #-}
19{-# LANGUAGE TypeOperators #-}
15{-# LANGUAGE UndecidableInstances #-}
20{-# LANGUAGE UndecidableInstances #-}
17−#if MIN_VERSION_base(4,9,0) && __GLASGOW_HASKELL__ >= 802
18−#define HAS_TYPE_ERROR
21module Servant.Server.Internal
22module Servant.Server.Internal
22 ( module Servant.Server.Internal
23 ( module Servant.Server.Internal
23 , module Servant.Server.Internal.BasicAuth
24 , module Servant.Server.Internal.BasicAuth
24 , module Servant.Server.Internal.Context
25 , module Servant.Server.Internal.Context
25 , module Servant.Server.Internal.Delayed
26 , module Servant.Server.Internal.Delayed
26 , module Servant.Server.Internal.DelayedIO
27 , module Servant.Server.Internal.DelayedIO
28+ , module Servant.Server.Internal.ErrorFormatter
27 , module Servant.Server.Internal.Handler
29 , module Servant.Server.Internal.Handler
28 , module Servant.Server.Internal.Router
30 , module Servant.Server.Internal.Router
29 , module Servant.Server.Internal.RouteResult
31 , module Servant.Server.Internal.RouteResult
@@ -34,19 +36,19 @@ module Servant.Server.Internal
34import Control.Monad
36import Control.Monad
35 (join, when)
37 (join, when)
36import Control.Monad.Trans
38import Control.Monad.Trans
37− (liftIO)
39+ (liftIO, lift)
38import Control.Monad.Trans.Resource
40import Control.Monad.Trans.Resource
39− (runResourceT)
41+ (runResourceT, ReleaseKey)
40import qualified Data.ByteString as B
43import qualified Data.ByteString as B
41import qualified Data.ByteString.Builder as BB
44import qualified Data.ByteString.Builder as BB
42import qualified Data.ByteString.Char8 as BC8
45import qualified Data.ByteString.Char8 as BC8
43import qualified Data.ByteString.Lazy as BL
46import qualified Data.ByteString.Lazy as BL
47+import Data.Constraint (Constraint, Dict(..))
44import Data.Either
48import Data.Either
45 (partitionEithers)
49 (partitionEithers)
46import Data.Maybe
50import Data.Maybe
47 (fromMaybe, isNothing, mapMaybe, maybeToList)
51 (fromMaybe, isNothing, mapMaybe, maybeToList)
50import Data.String
52import Data.String
51 (IsString (..))
53 (IsString (..))
52import Data.String.Conversions
54import Data.String.Conversions
@@ -55,58 +57,70 @@ import Data.Tagged
55 (Tagged (..), retag, untag)
57 (Tagged (..), retag, untag)
56import qualified Data.Text as T
58import qualified Data.Text as T
57import Data.Typeable
59import Data.Typeable
58import GHC.TypeLits
61import GHC.TypeLits
59− (KnownNat, KnownSymbol, natVal, symbolVal)
62+ (KnownNat, KnownSymbol, TypeError, symbolVal)
60import qualified Network.HTTP.Media as NHM
63import qualified Network.HTTP.Media as NHM
61import Network.HTTP.Types hiding
64import Network.HTTP.Types hiding
62 (Header, ResponseHeaders)
65 (Header, ResponseHeaders)
63import Network.Socket
66import Network.Socket
64 (SockAddr)
67 (SockAddr)
65import Network.Wai
68import Network.Wai
66− (Application, Request, httpVersion, isSecure, lazyRequestBody,
69+ (Application, Request, Response, ResponseReceived, httpVersion, isSecure, lazyRequestBody,
67− queryString, remoteHost, requestBody, requestHeaders,
70+ queryString, remoteHost, getRequestBodyChunk, requestHeaders,
68 requestMethod, responseLBS, responseStream, vault)
71 requestMethod, responseLBS, responseStream, vault)
69import Prelude ()
72import Prelude ()
70import Prelude.Compat
73import Prelude.Compat
71import Servant.API
74import Servant.API
72 ((:<|>) (..), (:>), Accept (..), BasicAuth, Capture',
75 ((:<|>) (..), (:>), Accept (..), BasicAuth, Capture',
73− CaptureAll, Description, EmptyAPI, FramingRender (..),
76+ CaptureAll, Description, EmptyAPI, Fragment,
74− FramingUnrender (..), FromSourceIO (..), Header', If,
77+ FramingRender (..), FramingUnrender (..), FromSourceIO (..),
75− IsSecure (..), QueryFlag, QueryParam', QueryParams, Raw,
78+ Header', If, IsSecure (..), NoContentVerb, QueryFlag,
76− ReflectMethod (reflectMethod), RemoteHost, ReqBody',
79+ QueryParam', QueryParams, Raw, RawM, ReflectMethod (reflectMethod),
77− SBool (..), SBoolI (..), SourceIO, Stream, StreamBody',
80+ RemoteHost, ReqBody', SBool (..), SBoolI (..), SourceIO,
78− Summary, ToSourceIO (..), Vault, Verb, NoContentVerb,
81+ Stream, StreamBody', Summary, ToSourceIO (..), Vault, Verb,
79− WithNamedContext)
82+ WithNamedContext, WithResource, NamedRoutes)
83+import Servant.API.Generic (GenericMode(..), ToServant, ToServantApi, GServantProduct, toServant, fromServant)
80import Servant.API.ContentTypes
84import Servant.API.ContentTypes
81 (AcceptHeader (..), AllCTRender (..), AllCTUnrender (..),
85 (AcceptHeader (..), AllCTRender (..), AllCTUnrender (..),
82− AllMime, MimeRender (..), MimeUnrender (..), canHandleAcceptH,
86+ AllMime, MimeRender (..), MimeUnrender (..), NoContent,
83− NoContent)
87+ canHandleAcceptH)
84import Servant.API.Modifiers
88import Servant.API.Modifiers
85 (FoldLenient, FoldRequired, RequestArgument,
89 (FoldLenient, FoldRequired, RequestArgument,
86 unfoldRequestArgument)
90 unfoldRequestArgument)
87import Servant.API.ResponseHeaders
91import Servant.API.ResponseHeaders
88 (GetHeaders, Headers, getHeaders, getResponse)
92 (GetHeaders, Headers, getHeaders, getResponse)
93+import Servant.API.Status
89import qualified Servant.Types.SourceT as S
95import qualified Servant.Types.SourceT as S
96+import Servant.API.TypeErrors
90import Web.HttpApiData
97import Web.HttpApiData
91− (FromHttpApiData, parseHeader, parseQueryParam,
98+ (FromHttpApiData, parseHeader, parseQueryParam, parseUrlPiece,
92− parseUrlPieces, parseUrlPiece)
99+ parseUrlPieces)
94import Servant.Server.Internal.BasicAuth
103import Servant.Server.Internal.BasicAuth
95import Servant.Server.Internal.Context
104import Servant.Server.Internal.Context
96import Servant.Server.Internal.Delayed
105import Servant.Server.Internal.Delayed
97import Servant.Server.Internal.DelayedIO
106import Servant.Server.Internal.DelayedIO
107+import Servant.Server.Internal.ErrorFormatter
98import Servant.Server.Internal.Handler
108import Servant.Server.Internal.Handler
99import Servant.Server.Internal.Router
109import Servant.Server.Internal.Router
100import Servant.Server.Internal.RouteResult
110import Servant.Server.Internal.RouteResult
101import Servant.Server.Internal.RoutingApplication
111import Servant.Server.Internal.RoutingApplication
102import Servant.Server.Internal.ServerError
112import Servant.Server.Internal.ServerError
104−#ifdef HAS_TYPE_ERROR
105import GHC.TypeLits
114import GHC.TypeLits
106 (ErrorMessage (..), TypeError)
115 (ErrorMessage (..), TypeError)
107−#endif
116+import Servant.API.TypeLevel
117+ (AtLeastOneFragment, FragmentUnique)
109class HasServer api context where
119class HasServer api context where
120+ -- | The type of a server for this API, given a monad to run effects in.
122+ -- Note that the result kind is @*@, so it is /not/ a monad transformer, unlike
123+ -- what the @T@ in the name might suggest.
110 type ServerT api (m :: * -> *) :: *
124 type ServerT api (m :: * -> *) :: *
@@ -168,7 +182,10 @@ instance (HasServer a context, HasServer b context) => HasServer (a :<|> b) cont
168-- > server = getBook
182-- > server = getBook
169-- > where getBook :: Text -> Handler Book
183-- > where getBook :: Text -> Handler Book
170-- > getBook isbn = ...
184-- > getBook isbn = ...
171−instance (KnownSymbol capture, FromHttpApiData a, HasServer api context, SBoolI (FoldLenient mods))
185+instance (KnownSymbol capture, FromHttpApiData a, Typeable a
186+ , HasServer api context, SBoolI (FoldLenient mods)
187+ , HasContextEntry (MkContextWithErrorFormatter context) ErrorFormatters
172 => HasServer (Capture' mods capture a :> api) context where
189 => HasServer (Capture' mods capture a :> api) context where
174 type ServerT (Capture' mods capture a :> api) m =
191 type ServerT (Capture' mods capture a :> api) m =
@@ -177,15 +194,19 @@ instance (KnownSymbol capture, FromHttpApiData a, HasServer api context, SBoolI
177 hoistServerWithContext _ pc nt s = hoistServerWithContext (Proxy :: Proxy api) pc nt . s
194 hoistServerWithContext _ pc nt s = hoistServerWithContext (Proxy :: Proxy api) pc nt . s
179 route Proxy context d =
196 route Proxy context d =
180− CaptureRouter $
197+ CaptureRouter [hint] $
181 route (Proxy :: Proxy api)
198 route (Proxy :: Proxy api)
183− (addCapture d $ \ txt -> case ( sbool :: SBool (FoldLenient mods)
200+ (addCapture d $ \ txt -> withRequest $ \ request ->
184− , parseUrlPiece txt :: Either T.Text a) of
201+ case ( sbool :: SBool (FoldLenient mods)
185− (SFalse, Left e) -> delayedFail err400 { errBody = cs e }
202+ , parseUrlPiece txt :: Either T.Text a) of
186− (SFalse, Right v) -> return v
203+ (SFalse, Left e) -> delayedFail $ formatError rep request $ cs e
187− (STrue, piece) -> return $ (either (Left . cs) Right) piece
204+ (SFalse, Right v) -> return v
188− )
205+ (STrue, piece) -> return $ (either (Left . cs) Right) piece)
207+ rep = typeRep (Proxy :: Proxy Capture')
208+ formatError = urlParseErrorFormatter $ getContextEntry (mkContextWithErrorFormatter context)
209+ hint = CaptureHint (T.pack $ symbolVal $ Proxy @capture) (typeRep (Proxy :: Proxy a))
190-- | If you use 'CaptureAll' in one of the endpoints for your API,
211-- | If you use 'CaptureAll' in one of the endpoints for your API,
191-- this automatically requires your server-side handler to be a
212-- this automatically requires your server-side handler to be a
@@ -204,7 +225,10 @@ instance (KnownSymbol capture, FromHttpApiData a, HasServer api context, SBoolI
204-- > server = getSourceFile
225-- > server = getSourceFile
205-- > where getSourceFile :: [Text] -> Handler Book
226-- > where getSourceFile :: [Text] -> Handler Book
206-- > getSourceFile pathSegments = ...
227-- > getSourceFile pathSegments = ...
207−instance (KnownSymbol capture, FromHttpApiData a, HasServer api context)
228+instance (KnownSymbol capture, FromHttpApiData a, Typeable a
229+ , HasServer api context
230+ , HasContextEntry (MkContextWithErrorFormatter context) ErrorFormatters
208 => HasServer (CaptureAll capture a :> api) context where
232 => HasServer (CaptureAll capture a :> api) context where
210 type ServerT (CaptureAll capture a :> api) m =
234 type ServerT (CaptureAll capture a :> api) m =
@@ -213,13 +237,53 @@ instance (KnownSymbol capture, FromHttpApiData a, HasServer api context)
213 hoistServerWithContext _ pc nt s = hoistServerWithContext (Proxy :: Proxy api) pc nt . s
237 hoistServerWithContext _ pc nt s = hoistServerWithContext (Proxy :: Proxy api) pc nt . s
215 route Proxy context d =
239 route Proxy context d =
216− CaptureAllRouter $
240+ CaptureAllRouter [hint] $
217 route (Proxy :: Proxy api)
241 route (Proxy :: Proxy api)
219− (addCapture d $ \ txts -> case parseUrlPieces txts of
243+ (addCapture d $ \ txts -> withRequest $ \ request ->
220− Left _ -> delayedFail err400
244+ case parseUrlPieces txts of
221− Right v -> return v
245+ Left e -> delayedFail $ formatError rep request $ cs e
249+ rep = typeRep (Proxy :: Proxy CaptureAll)
250+ formatError = urlParseErrorFormatter $ getContextEntry (mkContextWithErrorFormatter context)
251+ hint = CaptureHint (T.pack $ symbolVal $ Proxy @capture) (typeRep (Proxy :: Proxy [a]))
253+-- | If you use 'WithResource' in one of the endpoints for your API Servant
254+-- will provide the handler for this endpoint an argument of the specified type.
255+-- The lifespan of this resource will be automatically managed by Servant. This
256+-- resource will be created before the handler starts and it will be destoyed
257+-- after it ends. A new resource is created for each request to the endpoint.
259+-- The creation and destruction are done using a 'Data.Acquire.Acquire'
260+-- provided via server 'Context'.
264+-- > type MyApi = WithResource Handle :> "writeToFile" :> Post '[JSON] NoContent
266+-- > server :: Server MyApi
267+-- > server = writeToFile
268+-- > where writeToFile :: (ReleaseKey, Handle) -> Handler NoContent
269+-- > writeToFile (_, h) = hPutStrLn h "message"
271+-- In addition to the resource, the handler will also receive a 'ReleaseKey'
272+-- which can be used to deallocate the resource before the end of the request
275+instance (HasServer api ctx, HasContextEntry ctx (Acquire a))
276+ => HasServer (WithResource a :> api) ctx where
278+ type ServerT (WithResource a :> api) m = (ReleaseKey, a) -> ServerT api m
280+ hoistServerWithContext _ pc nt s = hoistServerWithContext (Proxy @api) pc nt . s
282+ route Proxy context d = route (Proxy @api) context (d `addParameterCheck` allocateResource)
284+ allocateResource :: DelayedIO (ReleaseKey, a)
285+ allocateResource = DelayedIO $ lift $ allocateAcquire (getContextEntry context)
225allowedMethodHead :: Method -> Request -> Bool
289allowedMethodHead :: Method -> Request -> Bool
@@ -240,10 +304,10 @@ methodCheck method request
240-- body check is no longer an option. However, we now run the accept
304-- body check is no longer an option. However, we now run the accept
241-- check before the body check and can therefore afford to make it
305-- check before the body check and can therefore afford to make it
242-- recoverable.
306-- recoverable.
243−acceptCheck :: (AllMime list) => Proxy list -> B.ByteString -> DelayedIO ()
307+acceptCheck :: (AllMime list) => Proxy list -> AcceptHeader -> DelayedIO ()
244acceptCheck proxy accH
308acceptCheck proxy accH
245− | canHandleAcceptH proxy (AcceptHeader accH) = return ()
309+ | canHandleAcceptH proxy accH = return ()
246− | otherwise = delayedFail err406
310+ | otherwise = delayedFail err406
248methodRouter :: (AllCTRender ctypes a)
312methodRouter :: (AllCTRender ctypes a)
249 => (b -> ([(HeaderName, B.ByteString)], a))
313 => (b -> ([(HeaderName, B.ByteString)], a))
@@ -253,12 +317,12 @@ methodRouter :: (AllCTRender ctypes a)
253methodRouter splitHeaders method proxy status action = leafRouter route'
317methodRouter splitHeaders method proxy status action = leafRouter route'
255 route' env request respond =
319 route' env request respond =
256− let accH = fromMaybe ct_wildcard $ lookup hAccept $ requestHeaders request
320+ let accH = getAcceptHeader request
257 in runAction (action `addMethodCheck` methodCheck method request
321 in runAction (action `addMethodCheck` methodCheck method request
258 `addAcceptCheck` acceptCheck proxy accH
322 `addAcceptCheck` acceptCheck proxy accH
259 ) env request respond $ \ output -> do
323 ) env request respond $ \ output -> do
260 let (headers, b) = splitHeaders output
324 let (headers, b) = splitHeaders output
261− case handleAcceptH proxy (AcceptHeader accH) b of
325+ case handleAcceptH proxy accH b of
262 Nothing -> FailFatal err406 -- this should not happen (checked before), so we make it fatal if it does
326 Nothing -> FailFatal err406 -- this should not happen (checked before), so we make it fatal if it does
263 Just (contentT, body) ->
327 Just (contentT, body) ->
264 let bdy = if allowedMethodHead method request then "" else body
328 let bdy = if allowedMethodHead method request then "" else body
@@ -284,7 +348,7 @@ instance {-# OVERLAPPABLE #-}
285 route Proxy _ = methodRouter ([],) method (Proxy :: Proxy ctypes) status
349 route Proxy _ = methodRouter ([],) method (Proxy :: Proxy ctypes) status
286 where method = reflectMethod (Proxy :: Proxy method)
350 where method = reflectMethod (Proxy :: Proxy method)
287− status = toEnum . fromInteger $ natVal (Proxy :: Proxy status)
351+ status = statusFromNat (Proxy :: Proxy status)
289instance {-# OVERLAPPING #-}
353instance {-# OVERLAPPING #-}
290 ( AllCTRender ctypes a, ReflectMethod method, KnownNat status
354 ( AllCTRender ctypes a, ReflectMethod method, KnownNat status
@@ -296,7 +360,7 @@ instance {-# OVERLAPPING #-}
297 route Proxy _ = methodRouter (\x -> (getHeaders x, getResponse x)) method (Proxy :: Proxy ctypes) status
361 route Proxy _ = methodRouter (\x -> (getHeaders x, getResponse x)) method (Proxy :: Proxy ctypes) status
298 where method = reflectMethod (Proxy :: Proxy method)
362 where method = reflectMethod (Proxy :: Proxy method)
299− status = toEnum . fromInteger $ natVal (Proxy :: Proxy status)
363+ status = statusFromNat (Proxy :: Proxy status)
301instance (ReflectMethod method) =>
365instance (ReflectMethod method) =>
302 HasServer (NoContentVerb method) context where
366 HasServer (NoContentVerb method) context where
@@ -317,7 +381,7 @@ instance {-# OVERLAPPABLE #-}
318 route Proxy _ = streamRouter ([],) method status (Proxy :: Proxy framing) (Proxy :: Proxy ctype)
382 route Proxy _ = streamRouter ([],) method status (Proxy :: Proxy framing) (Proxy :: Proxy ctype)
319 where method = reflectMethod (Proxy :: Proxy method)
383 where method = reflectMethod (Proxy :: Proxy method)
320− status = toEnum . fromInteger $ natVal (Proxy :: Proxy status)
384+ status = statusFromNat (Proxy :: Proxy status)
323instance {-# OVERLAPPING #-}
387instance {-# OVERLAPPING #-}
@@ -331,7 +395,7 @@ instance {-# OVERLAPPING #-}
332 route Proxy _ = streamRouter (\x -> (getHeaders x, getResponse x)) method status (Proxy :: Proxy framing) (Proxy :: Proxy ctype)
396 route Proxy _ = streamRouter (\x -> (getHeaders x, getResponse x)) method status (Proxy :: Proxy framing) (Proxy :: Proxy ctype)
333 where method = reflectMethod (Proxy :: Proxy method)
397 where method = reflectMethod (Proxy :: Proxy method)
334− status = toEnum . fromInteger $ natVal (Proxy :: Proxy status)
398+ status = statusFromNat (Proxy :: Proxy status)
337streamRouter :: forall ctype a c chunk env framing. (MimeRender ctype chunk, FramingRender framing, ToSourceIO chunk a) =>
401streamRouter :: forall ctype a c chunk env framing. (MimeRender ctype chunk, FramingRender framing, ToSourceIO chunk a) =>
@@ -343,7 +407,7 @@ streamRouter :: forall ctype a c chunk env framing. (MimeRender ctype chunk, Fra
343 -> Delayed env (Handler c)
407 -> Delayed env (Handler c)
344 -> Router env
408 -> Router env
345streamRouter splitHeaders method status framingproxy ctypeproxy action = leafRouter $ \env request respond ->
409streamRouter splitHeaders method status framingproxy ctypeproxy action = leafRouter $ \env request respond ->
346− let accH = fromMaybe ct_wildcard $ lookup hAccept $ requestHeaders request
410+ let AcceptHeader accH = getAcceptHeader request
347 cmediatype = NHM.matchAccept [contentType ctypeproxy] accH
411 cmediatype = NHM.matchAccept [contentType ctypeproxy] accH
348 accCheck = when (isNothing cmediatype) $ delayedFail err406
412 accCheck = when (isNothing cmediatype) $ delayedFail err406
349 contentHeader = (hContentType, NHM.renderHeader . maybeToList $ cmediatype)
413 contentHeader = (hContentType, NHM.renderHeader . maybeToList $ cmediatype)
@@ -388,6 +452,7 @@ streamRouter splitHeaders method status framingproxy ctypeproxy action = leafRou
389 (KnownSymbol sym, FromHttpApiData a, HasServer api context
453 (KnownSymbol sym, FromHttpApiData a, HasServer api context
390 , SBoolI (FoldRequired mods), SBoolI (FoldLenient mods)
454 , SBoolI (FoldRequired mods), SBoolI (FoldLenient mods)
455+ , HasContextEntry (MkContextWithErrorFormatter context) ErrorFormatters
392 => HasServer (Header' mods sym a :> api) context where
457 => HasServer (Header' mods sym a :> api) context where
@@ -399,6 +464,9 @@ instance
399 route Proxy context subserver = route (Proxy :: Proxy api) context $
464 route Proxy context subserver = route (Proxy :: Proxy api) context $
400 subserver `addHeaderCheck` withRequest headerCheck
465 subserver `addHeaderCheck` withRequest headerCheck
467+ rep = typeRep (Proxy :: Proxy Header')
468+ formatError = headerParseErrorFormatter $ getContextEntry (mkContextWithErrorFormatter context)
402 headerName :: IsString n => n
470 headerName :: IsString n => n
403 headerName = fromString $ symbolVal (Proxy :: Proxy sym)
471 headerName = fromString $ symbolVal (Proxy :: Proxy sym)
@@ -409,15 +477,13 @@ instance
409 mev :: Maybe (Either T.Text a)
477 mev :: Maybe (Either T.Text a)
410 mev = fmap parseHeader $ lookup headerName (requestHeaders req)
478 mev = fmap parseHeader $ lookup headerName (requestHeaders req)
412− errReq = delayedFailFatal err400
480+ errReq = delayedFailFatal $ formatError rep req
413− { errBody = "Header " <> headerName <> " is required"
481+ $ "Header " <> headerName <> " is required"
416− errSt e = delayedFailFatal err400
483+ errSt e = delayedFailFatal $ formatError rep req
417− { errBody = cs $ "Error parsing header "
484+ $ cs $ "Error parsing header "
418− <> headerName
485+ <> headerName
419− <> " failed: " <> e
486+ <> " failed: " <> e
422-- | If you use @'QueryParam' "author" Text@ in one of the endpoints for your API,
488-- | If you use @'QueryParam' "author" Text@ in one of the endpoints for your API,
423-- this automatically requires your server-side handler to be a function
489-- this automatically requires your server-side handler to be a function
@@ -443,6 +509,7 @@ instance
444 ( KnownSymbol sym, FromHttpApiData a, HasServer api context
510 ( KnownSymbol sym, FromHttpApiData a, HasServer api context
445 , SBoolI (FoldRequired mods), SBoolI (FoldLenient mods)
511 , SBoolI (FoldRequired mods), SBoolI (FoldLenient mods)
512+ , HasContextEntry (MkContextWithErrorFormatter context) ErrorFormatters
447 => HasServer (QueryParam' mods sym a :> api) context where
514 => HasServer (QueryParam' mods sym a :> api) context where
@@ -455,6 +522,9 @@ instance
455 let querytext = queryToQueryText . queryString
522 let querytext = queryToQueryText . queryString
456 paramname = cs $ symbolVal (Proxy :: Proxy sym)
523 paramname = cs $ symbolVal (Proxy :: Proxy sym)
525+ rep = typeRep (Proxy :: Proxy QueryParam')
526+ formatError = urlParseErrorFormatter $ getContextEntry (mkContextWithErrorFormatter context)
458 parseParam :: Request -> DelayedIO (RequestArgument mods a)
528 parseParam :: Request -> DelayedIO (RequestArgument mods a)
459 parseParam req =
529 parseParam req =
460 unfoldRequestArgument (Proxy :: Proxy mods) errReq errSt mev
530 unfoldRequestArgument (Proxy :: Proxy mods) errReq errSt mev
@@ -462,14 +532,12 @@ instance
462 mev :: Maybe (Either T.Text a)
532 mev :: Maybe (Either T.Text a)
463 mev = fmap parseQueryParam $ join $ lookup paramname $ querytext req
533 mev = fmap parseQueryParam $ join $ lookup paramname $ querytext req
465− errReq = delayedFailFatal err400
535+ errReq = delayedFailFatal $ formatError rep req
466− { errBody = cs $ "Query parameter " <> paramname <> " is required"
536+ $ cs $ "Query parameter " <> paramname <> " is required"
469− errSt e = delayedFailFatal err400
538+ errSt e = delayedFailFatal $ formatError rep req
470− { errBody = cs $ "Error parsing query parameter "
539+ $ cs $ "Error parsing query parameter "
471− <> paramname <> " failed: " <> e
540+ <> paramname <> " failed: " <> e
474 delayed = addParameterCheck subserver . withRequest $ \req ->
542 delayed = addParameterCheck subserver . withRequest $ \req ->
475 parseParam req
543 parseParam req
@@ -495,7 +563,8 @@ instance
495-- > server = getBooksBy
563-- > server = getBooksBy
496-- > where getBooksBy :: [Text] -> Handler [Book]
564-- > where getBooksBy :: [Text] -> Handler [Book]
497-- > getBooksBy authors = ...return all books by these authors...
565-- > getBooksBy authors = ...return all books by these authors...
498−instance (KnownSymbol sym, FromHttpApiData a, HasServer api context)
566+instance (KnownSymbol sym, FromHttpApiData a, HasServer api context
567+ , HasContextEntry (MkContextWithErrorFormatter context) ErrorFormatters)
499 => HasServer (QueryParams sym a :> api) context where
568 => HasServer (QueryParams sym a :> api) context where
501 type ServerT (QueryParams sym a :> api) m =
570 type ServerT (QueryParams sym a :> api) m =
@@ -506,21 +575,23 @@ instance (KnownSymbol sym, FromHttpApiData a, HasServer api context)
506 route Proxy context subserver = route (Proxy :: Proxy api) context $
575 route Proxy context subserver = route (Proxy :: Proxy api) context $
507 subserver `addParameterCheck` withRequest paramsCheck
576 subserver `addParameterCheck` withRequest paramsCheck
578+ rep = typeRep (Proxy :: Proxy QueryParams)
579+ formatError = urlParseErrorFormatter $ getContextEntry (mkContextWithErrorFormatter context)
509 paramname = cs $ symbolVal (Proxy :: Proxy sym)
581 paramname = cs $ symbolVal (Proxy :: Proxy sym)
510 paramsCheck req =
582 paramsCheck req =
511 case partitionEithers $ fmap parseQueryParam params of
583 case partitionEithers $ fmap parseQueryParam params of
512 ([], parsed) -> return parsed
584 ([], parsed) -> return parsed
513− (errs, _) -> delayedFailFatal err400
585+ (errs, _) -> delayedFailFatal $ formatError rep req
514− { errBody = cs $ "Error parsing query parameter(s) "
586+ $ cs $ "Error parsing query parameter(s) "
515− <> paramname <> " failed: "
587+ <> paramname <> " failed: "
516− <> T.intercalate ", " errs
588+ <> T.intercalate ", " errs
519 params :: [T.Text]
590 params :: [T.Text]
520 params = mapMaybe snd
591 params = mapMaybe snd
521 . filter (looksLikeParam . fst)
592 . filter (looksLikeParam . fst)
522− . queryToQueryText
593+ . queryToQueryText
523− . queryString
594+ . queryString
526 looksLikeParam name = name == paramname || name == (paramname <> "[]")
597 looksLikeParam name = name == paramname || name == (paramname <> "[]")
@@ -582,13 +653,42 @@ instance HasServer Raw context where
582 Fail a -> respond $ Fail a
653 Fail a -> respond $ Fail a
583 FailFatal e -> respond $ FailFatal e
654 FailFatal e -> respond $ FailFatal e
656+-- | Just pass the request to the underlying application and serve its response.
660+-- > type MyApi = "images" :> Raw
662+-- > server :: Server MyApi
663+-- > server = serveDirectory "/var/www/images"
664+instance HasServer RawM context where
665+ type ServerT RawM m = Request -> (Response -> IO ResponseReceived) -> m ResponseReceived
670+ -> Delayed env (Request -> (Response -> IO ResponseReceived) -> Handler ResponseReceived) -> Router env
671+ route _ _ handleDelayed = RawRouter $ \env request respond -> runResourceT $ do
672+ routeResult <- runDelayed handleDelayed env request
673+ let respond' = liftIO . respond
674+ liftIO $ case routeResult of
675+ Route handler -> runHandler (handler request (respond . Route)) >>=
677+ Left e -> respond' $ FailFatal e
679+ Fail e -> respond' $ Fail e
680+ FailFatal e -> respond' $ FailFatal e
682+ hoistServerWithContext _ _ f srvM = \req respond -> f (srvM req respond)
585-- | If you use 'ReqBody' in one of the endpoints for your API,
685-- | If you use 'ReqBody' in one of the endpoints for your API,
586-- this automatically requires your server-side handler to be a function
686-- this automatically requires your server-side handler to be a function
587-- that takes an argument of the type specified by 'ReqBody'.
687-- that takes an argument of the type specified by 'ReqBody'.
588-- The @Content-Type@ header is inspected, and the list provided is used to
688-- The @Content-Type@ header is inspected, and the list provided is used to
589-- attempt deserialization. If the request does not have a @Content-Type@
689-- attempt deserialization. If the request does not have a @Content-Type@
590-- header, it is treated as @application/octet-stream@ (as specified in
690-- header, it is treated as @application/octet-stream@ (as specified in
591−-- <http://tools.ietf.org/html/rfc7231#section-3.1.1.5 RFC7231>.
691+-- [RFC 7231 section 3.1.1.5](http://tools.ietf.org/html/rfc7231#section-3.1.1.5)).
592-- This lets servant worry about extracting it from the request and turning
692-- This lets servant worry about extracting it from the request and turning
593-- it into a value of the type you specify.
693-- it into a value of the type you specify.
@@ -604,6 +704,7 @@ instance HasServer Raw context where
604-- > where postBook :: Book -> Handler Book
704-- > where postBook :: Book -> Handler Book
605-- > postBook book = ...insert into your db...
705-- > postBook book = ...insert into your db...
606instance ( AllCTUnrender list a, HasServer api context, SBoolI (FoldLenient mods)
706instance ( AllCTUnrender list a, HasServer api context, SBoolI (FoldLenient mods)
707+ , HasContextEntry (MkContextWithErrorFormatter context) ErrorFormatters
607 ) => HasServer (ReqBody' mods list a :> api) context where
708 ) => HasServer (ReqBody' mods list a :> api) context where
609 type ServerT (ReqBody' mods list a :> api) m =
710 type ServerT (ReqBody' mods list a :> api) m =
@@ -615,6 +716,9 @@ instance ( AllCTUnrender list a, HasServer api context, SBoolI (FoldLenient mods
615 = route (Proxy :: Proxy api) context $
716 = route (Proxy :: Proxy api) context $
616 addBodyCheck subserver ctCheck bodyCheck
717 addBodyCheck subserver ctCheck bodyCheck
719+ rep = typeRep (Proxy :: Proxy ReqBody')
720+ formatError = bodyParserErrorFormatter $ getContextEntry (mkContextWithErrorFormatter context)
618 -- Content-Type check, we only lookup we can try to parse the request body
722 -- Content-Type check, we only lookup we can try to parse the request body
619 ctCheck = withRequest $ \ request -> do
723 ctCheck = withRequest $ \ request -> do
620 -- See HTTP RFC 2616, section 7.2.1
724 -- See HTTP RFC 2616, section 7.2.1
@@ -633,7 +737,7 @@ instance ( AllCTUnrender list a, HasServer api context, SBoolI (FoldLenient mods
633 case sbool :: SBool (FoldLenient mods) of
737 case sbool :: SBool (FoldLenient mods) of
634 STrue -> return mrqbody
738 STrue -> return mrqbody
635 SFalse -> case mrqbody of
739 SFalse -> case mrqbody of
636− Left e -> delayedFailFatal err400 { errBody = cs e }
740+ Left e -> delayedFailFatal $ formatError rep request e
637 Right v -> return v
741 Right v -> return v
@@ -656,7 +760,7 @@ instance
656 bodyCheck fromRS = withRequest $ \req -> do
760 bodyCheck fromRS = withRequest $ \req -> do
657 let mimeUnrender' = mimeUnrender (Proxy :: Proxy ctype) :: BL.ByteString -> Either String chunk
761 let mimeUnrender' = mimeUnrender (Proxy :: Proxy ctype) :: BL.ByteString -> Either String chunk
658 let framingUnrender' = framingUnrender (Proxy :: Proxy framing) mimeUnrender' :: SourceIO B.ByteString -> SourceIO chunk
762 let framingUnrender' = framingUnrender (Proxy :: Proxy framing) mimeUnrender' :: SourceIO B.ByteString -> SourceIO chunk
659− let body = requestBody req
763+ let body = getRequestBodyChunk req
660 let rs = S.fromAction B.null body
764 let rs = S.fromAction B.null body
661 let rs' = fromRS $ framingUnrender' rs
765 let rs' = fromRS $ framingUnrender' rs
662 return rs'
766 return rs'
@@ -725,12 +829,12 @@ data EmptyServer = EmptyServer deriving (Typeable, Eq, Show, Bounded, Enum)
725emptyServer :: ServerT EmptyAPI m
829emptyServer :: ServerT EmptyAPI m
726emptyServer = Tagged EmptyServer
830emptyServer = Tagged EmptyServer
728−-- | The server for an `EmptyAPI` is `emptyAPIServer`.
832+-- | The server for an `EmptyAPI` is `emptyServer`.
730-- > type MyApi = "nothing" :> EmptyApi
834-- > type MyApi = "nothing" :> EmptyApi
732-- > server :: Server MyApi
836-- > server :: Server MyApi
733−-- > server = emptyAPIServer
837+-- > server = emptyServer
734instance HasServer EmptyAPI context where
838instance HasServer EmptyAPI context where
735 type ServerT EmptyAPI m = Tagged m EmptyServer
839 type ServerT EmptyAPI m = Tagged m EmptyServer
@@ -759,7 +863,10 @@ instance ( KnownSymbol realm
759-- * helpers
863-- * helpers
761ct_wildcard :: B.ByteString
865ct_wildcard :: B.ByteString
762−ct_wildcard = "*" <> "/" <> "*" -- Because CPP
866+ct_wildcard = "*" <> "/" <> "*"
868+getAcceptHeader :: Request -> AcceptHeader
869+getAcceptHeader = AcceptHeader . fromMaybe ct_wildcard . lookup hAccept . requestHeaders
764-- * General Authentication
871-- * General Authentication
@@ -784,39 +891,19 @@ instance (HasContextEntry context (NamedContext name subContext), HasServer subA
784 hoistServerWithContext _ _ nt s = hoistServerWithContext (Proxy :: Proxy subApi) (Proxy :: Proxy subContext) nt s
891 hoistServerWithContext _ _ nt s = hoistServerWithContext (Proxy :: Proxy subApi) (Proxy :: Proxy subContext) nt s
786-------------------------------------------------------------------------------
893-------------------------------------------------------------------------------
787−-- TypeError helpers
894+-- Custom type errors
788-------------------------------------------------------------------------------
895-------------------------------------------------------------------------------
790−#ifdef HAS_TYPE_ERROR
897+-- Erroring instance for 'HasServer' when a combinator is not fully applied
791−-- | This instance catches mistakes when there are non-saturated
898+instance TypeError (PartialApplication
792−-- type applications on LHS of ':>'.
899+#if __GLASGOW_HASKELL__ >= 904
793−--
900+ @(Type -> [Type] -> Constraint)
794−-- >>> serve (Proxy :: Proxy (Capture "foo" :> Get '[JSON] Int)) (error "...")
901+#endif
795−-- ...
902+ HasServer arr) => HasServer ((arr :: a -> b) :> sub) context
796−-- ...Expected something of kind Symbol or *, got: k -> l on the LHS of ':>'.
797−-- ...Maybe you haven't applied enough arguments to
798−-- ...Capture' '[] "foo"
801−-- >>> undefined :: Server (Capture "foo" :> Get '[JSON] Int)
803−-- ...Expected something of kind Symbol or *, got: k -> l on the LHS of ':>'.
804−-- ...Maybe you haven't applied enough arguments to
805−-- ...Capture' '[] "foo"
808−instance TypeError (HasServerArrowKindError arr) => HasServer ((arr :: k -> l) :> api) context
810− type ServerT (arr :> api) m = TypeError (HasServerArrowKindError arr)
904+ type ServerT (arr :> sub) _ = TypeError (PartialApplication (HasServer :: * -> [*] -> Constraint) arr)
811− -- it doens't really matter what sub route we peak
905+ route = error "unreachable"
812− route _ _ _ = error "servant-server panic: impossible happened in HasServer (arr :> api)"
906+ hoistServerWithContext _ _ _ _ = error "unreachable"
813− hoistServerWithContext _ _ _ = id
815−-- Cannot have TypeError here, otherwise use of this symbol will error :)
816−type HasServerArrowKindError arr =
817− 'Text "Expected something of kind Symbol or *, got: k -> l on the LHS of ':>'."
818− ':$$: 'Text "Maybe you haven't applied enough arguments to"
821-- | This instance prevents from accidentally using '->' instead of ':>'
908-- | This instance prevents from accidentally using '->' instead of ':>'
@@ -850,7 +937,107 @@ type HasServerArrowTypeError a b =
850 ':$$: 'ShowType a
937 ':$$: 'ShowType a
851 ':$$: 'Text "and"
938 ':$$: 'Text "and"
852 ':$$: 'ShowType b
939 ':$$: 'ShowType b
941+-- Erroring instances for 'HasServer' for unknown API combinators
943+-- XXX: This omits the @context@ parameter, e.g.:
945+-- "There is no instance for HasServer (Bool :> …)". Do we care ?
946+instance {-# OVERLAPPABLE #-} TypeError (NoInstanceForSub
947+#if __GLASGOW_HASKELL__ >= 904
948+ @(Type -> [Type] -> Constraint)
950+ HasServer ty) => HasServer (ty :> sub) context
952+instance {-# OVERLAPPABLE #-} TypeError (NoInstanceFor (HasServer api context)) => HasServer api context
954+-- | Ignore @'Fragment'@ in server handlers.
955+-- See <https://ietf.org/rfc/rfc2616.html#section-15.1.3> for more details.
959+-- > type MyApi = "books" :> Fragment Text :> Get '[JSON] [Book]
961+-- > server :: Server MyApi
962+-- > server = getBooks
963+-- > where getBooks :: Handler [Book]
964+-- > getBooks = ...return all books...
965+instance (AtLeastOneFragment api, FragmentUnique (Fragment a1 :> api), HasServer api context)
966+ => HasServer (Fragment a1 :> api) context where
967+ type ServerT (Fragment a1 :> api) m = ServerT api m
969+ route _ = route (Proxy :: Proxy api)
971+ hoistServerWithContext _ = hoistServerWithContext (Proxy :: Proxy api)
856-- >>> import Servant
974-- >>> import Servant
976+-- | A type that specifies that an API record contains a server implementation.
977+data AsServerT (m :: * -> *)
978+instance GenericMode (AsServerT m) where
979+ type AsServerT m :- api = ServerT api m
981+type AsServer = AsServerT Handler
984+-- | Set of constraints required to convert to / from vanilla server types.
985+type GServerConstraints api m =
986+ ( ToServant api (AsServerT m) ~ ServerT (ToServantApi api) m
987+ , GServantProduct (Rep (api (AsServerT m)))
990+-- | This class is a necessary evil: in the implementation of 'HasServer' for
991+-- @'NamedRoutes' api@, we essentially need the quantified constraint @forall
992+-- m. 'GServerConstraints' m@ to hold.
994+-- We cannot require do that directly as the definition of 'GServerConstraints'
995+-- contains type family applications ('Rep' and 'ServerT'). The trick is to hide
996+-- those type family applications behind a typeclass providing evidence for
997+-- @'GServerConstraints' api m@ in the form of a dictionary, and require that
998+-- @forall m. 'GServer' api m@ instead.
1000+-- Users shouldn't have to worry about this class, as the only possible instance
1001+-- is provided in this module for all record APIs.
1003+class GServer (api :: * -> *) (m :: * -> *) where
1004+ gServerProof :: Dict (GServerConstraints api m)
1007+ ( ToServant api (AsServerT m) ~ ServerT (ToServantApi api) m
1008+ , GServantProduct (Rep (api (AsServerT m)))
1009+ ) => GServer api m where
1010+ gServerProof = Dict
1013+ ( HasServer (ToServantApi api) context
1014+ , forall m. Generic (api (AsServerT m))
1015+ , forall m. GServer api m
1016+ ) => HasServer (NamedRoutes api) context where
1018+ type ServerT (NamedRoutes api) m = api (AsServerT m)
1021+ :: Proxy (NamedRoutes api)
1023+ -> Delayed env (api (AsServerT Handler))
1025+ route _ ctx delayed =
1026+ case gServerProof @api @Handler of
1027+ Dict -> route (Proxy @(ToServantApi api)) ctx (toServant <$> delayed)
1029+ hoistServerWithContext
1030+ :: forall m n. Proxy (NamedRoutes api)
1032+ -> (forall x. m x -> n x)
1033+ -> api (AsServerT m)
1034+ -> api (AsServerT n)
1035+ hoistServerWithContext _ pctx nat server =
1036+ case (gServerProof @api @m, gServerProof @api @n) of
1038+ fromServant servantSrvN
1040+ servantSrvM :: ServerT (ToServantApi api) m =
1042+ servantSrvN :: ServerT (ToServantApi api) n =
1043+ hoistServerWithContext (Proxy @(ToServantApi api)) pctx nat servantSrvM