@@ -1,993 +0,0 @@
1−{-# LANGUAGE ConstraintKinds #-}
2−{-# LANGUAGE DataKinds #-}
3−{-# LANGUAGE FlexibleContexts #-}
4−{-# LANGUAGE FlexibleInstances #-}
5−{-# LANGUAGE InstanceSigs #-}
6−{-# LANGUAGE MultiParamTypeClasses #-}
7−{-# LANGUAGE OverloadedStrings #-}
8−{-# LANGUAGE PolyKinds #-}
9−{-# LANGUAGE QuantifiedConstraints #-}
10−{-# LANGUAGE RankNTypes #-}
11−{-# LANGUAGE ScopedTypeVariables #-}
12−{-# LANGUAGE TypeApplications #-}
13−{-# LANGUAGE TypeFamilies #-}
14−{-# LANGUAGE TypeOperators #-}
15−{-# LANGUAGE UndecidableInstances #-}
16−
17−module Servant.Client.Core.HasClient (
18− clientIn,
19− HasClient (..),
20− EmptyClient (..),
21− AsClientT,
22− (//),
23− (/:),
24− foldMapUnion,
25− matchUnion,
26− ) where
27−
28−import Prelude ()
29−import Prelude.Compat
30−
31−import Control.Arrow
32− (left, (+++))
33−import Control.Monad
34− (unless)
35−import qualified Data.ByteString as BS
36−import qualified Data.ByteString.Lazy as BL
37−import Data.Either
38− (partitionEithers)
39−import Data.Constraint (Dict(..))
40−import Data.Foldable
41− (toList)
42−import Data.List
43− (foldl')
44−import Data.Sequence
45− (fromList)
46−import qualified Data.Text as T
47−import Network.HTTP.Media
48− (MediaType, matches, parseAccept)
49−import qualified Network.HTTP.Media as Media
50−import qualified Data.Sequence as Seq
51−import Data.SOP.BasicFunctors
52− (I (I), (:.:) (Comp))
53−import Data.SOP.Constraint
54− (All)
55−import Data.SOP.NP
56− (NP (..), cpure_NP)
57−import Data.SOP.NS
58− (NS (S))
59−import Data.String
60− (fromString)
61−import Data.Text
62− (Text, pack)
63−import Data.Proxy
64− (Proxy (Proxy))
65−import GHC.TypeLits
66− (KnownNat, KnownSymbol, TypeError, symbolVal)
67−import Network.HTTP.Types
68− (Status)
69−import qualified Network.HTTP.Types as H
70−import Servant.API
71− ((:<|>) ((:<|>)), (:>), AuthProtect, BasicAuth, BasicAuthData,
72− BuildHeadersTo (..), Capture', CaptureAll, Description,
73− EmptyAPI, Fragment, FramingRender (..), FramingUnrender (..),
74− FromSourceIO (..), Header', Headers (..), HttpVersion,
75− IsSecure, MimeRender (mimeRender),
76− MimeUnrender (mimeUnrender), NoContent (NoContent),
77− NoContentVerb, QueryFlag, QueryParam', QueryParams, Raw,
78− ReflectMethod (..), RemoteHost, ReqBody', SBoolI, Stream,
79− StreamBody', Summary, ToHttpApiData, ToSourceIO (..), Vault,
80− Verb, WithNamedContext, WithStatus (..), contentType, getHeadersHList,
81− getResponse, toEncodedUrlPiece, toUrlPiece, NamedRoutes)
82−import Servant.API.Generic
83− (GenericMode(..), ToServant, ToServantApi
84− , GenericServant, toServant, fromServant)
85−import Servant.API.ContentTypes
86− (contentTypes, AllMime (allMime), AllMimeUnrender (allMimeUnrender))
87−import Servant.API.Status
88− (statusFromNat)
89−import Servant.API.TypeLevel (FragmentUnique, AtLeastOneFragment)
90−import Servant.API.Modifiers
91− (FoldRequired, RequiredArgument, foldRequiredArgument)
92−import Servant.API.TypeErrors
93−import Servant.API.UVerb
94− (HasStatus, HasStatuses (Statuses, statuses), UVerb, Union, Unique, inject, statusOf, foldMapUnion, matchUnion)
95−
96−import Servant.Client.Core.Auth
97−import Servant.Client.Core.BasicAuth
98−import Servant.Client.Core.ClientError
99−import Servant.Client.Core.Request
100−import Servant.Client.Core.Response
101−import Servant.Client.Core.RunClient
102−
103−-- * Accessing APIs as a Client
104−
105−-- | 'clientIn' allows you to produce operations to query an API from a client
106−-- within a 'RunClient' monad.
107−--
108−-- > type MyApi = "books" :> Get '[JSON] [Book] -- GET /books
109−-- > :<|> "books" :> ReqBody '[JSON] Book :> Post '[JSON] Book -- POST /books
110−-- >
111−-- > myApi :: Proxy MyApi
112−-- > myApi = Proxy
113−-- >
114−-- > clientM :: Proxy ClientM
115−-- > clientM = Proxy
116−-- >
117−-- > getAllBooks :: ClientM [Book]
118−-- > postNewBook :: Book -> ClientM Book
119−-- > (getAllBooks :<|> postNewBook) = myApi `clientIn` clientM
120−clientIn :: HasClient m api => Proxy api -> Proxy m -> Client m api
121−clientIn p pm = clientWithRoute pm p defaultRequest
122−
123−
124−-- | This class lets us define how each API combinator influences the creation
125−-- of an HTTP request.
126−--
127−-- Unless you are writing a new backend for @servant-client-core@ or new
128−-- combinators that you want to support client-generation, you can ignore this
129−-- class.
130−class RunClient m => HasClient m api where
131− type Client (m :: * -> *) (api :: *) :: *
132− clientWithRoute :: Proxy m -> Proxy api -> Request -> Client m api
133− hoistClientMonad
134− :: Proxy m
135− -> Proxy api
136− -> (forall x. mon x -> mon' x)
137− -> Client mon api
138− -> Client mon' api
139−
140−
141−-- | A client querying function for @a ':<|>' b@ will actually hand you
142−-- one function for querying @a@ and another one for querying @b@,
143−-- stitching them together with ':<|>', which really is just like a pair.
144−--
145−-- > type MyApi = "books" :> Get '[JSON] [Book] -- GET /books
146−-- > :<|> "books" :> ReqBody '[JSON] Book :> Post Book -- POST /books
147−-- >
148−-- > myApi :: Proxy MyApi
149−-- > myApi = Proxy
150−-- >
151−-- > getAllBooks :: ClientM [Book]
152−-- > postNewBook :: Book -> ClientM Book
153−-- > (getAllBooks :<|> postNewBook) = client myApi
154−instance (HasClient m a, HasClient m b) => HasClient m (a :<|> b) where
155− type Client m (a :<|> b) = Client m a :<|> Client m b
156− clientWithRoute pm Proxy req =
157− clientWithRoute pm (Proxy :: Proxy a) req :<|>
158− clientWithRoute pm (Proxy :: Proxy b) req
159−
160− hoistClientMonad pm _ f (ca :<|> cb) =
161− hoistClientMonad pm (Proxy :: Proxy a) f ca :<|>
162− hoistClientMonad pm (Proxy :: Proxy b) f cb
163−
164−-- | Singleton type representing a client for an empty API.
165−data EmptyClient = EmptyClient deriving (Eq, Show, Bounded, Enum)
166−
167−-- | The client for 'EmptyAPI' is simply 'EmptyClient'.
168−--
169−-- > type MyAPI = "books" :> Get '[JSON] [Book] -- GET /books
170−-- > :<|> "nothing" :> EmptyAPI
171−-- >
172−-- > myApi :: Proxy MyApi
173−-- > myApi = Proxy
174−-- >
175−-- > getAllBooks :: ClientM [Book]
176−-- > (getAllBooks :<|> EmptyClient) = client myApi
177−instance RunClient m => HasClient m EmptyAPI where
178− type Client m EmptyAPI = EmptyClient
179− clientWithRoute _pm Proxy _ = EmptyClient
180− hoistClientMonad _ _ _ EmptyClient = EmptyClient
181−
182−-- | If you use a 'Capture' in one of your endpoints in your API,
183−-- the corresponding querying function will automatically take
184−-- an additional argument of the type specified by your 'Capture'.
185−-- That function will take care of inserting a textual representation
186−-- of this value at the right place in the request path.
187−--
188−-- You can control how values for this type are turned into
189−-- text by specifying a 'ToHttpApiData' instance for your type.
190−--
191−-- Example:
192−--
193−-- > type MyApi = "books" :> Capture "isbn" Text :> Get '[JSON] Book
194−-- >
195−-- > myApi :: Proxy MyApi
196−-- > myApi = Proxy
197−-- >
198−-- > getBook :: Text -> ClientM Book
199−-- > getBook = client myApi
200−-- > -- then you can just use "getBook" to query that endpoint
201−instance (KnownSymbol capture, ToHttpApiData a, HasClient m api)
202− => HasClient m (Capture' mods capture a :> api) where
203−
204− type Client m (Capture' mods capture a :> api) =
205− a -> Client m api
206−
207− clientWithRoute pm Proxy req val =
208− clientWithRoute pm (Proxy :: Proxy api)
209− (appendToPath p req)
210−
211− where p = toEncodedUrlPiece val
212−
213− hoistClientMonad pm _ f cl = \a ->
214− hoistClientMonad pm (Proxy :: Proxy api) f (cl a)
215−
216−-- | If you use a 'CaptureAll' in one of your endpoints in your API,
217−-- the corresponding querying function will automatically take an
218−-- additional argument of a list of the type specified by your
219−-- 'CaptureAll'. That function will take care of inserting a textual
220−-- representation of this value at the right place in the request
221−-- path.
222−--
223−-- You can control how these values are turned into text by specifying
224−-- a 'ToHttpApiData' instance of your type.
225−--
226−-- Example:
227−--
228−-- > type MyAPI = "src" :> CaptureAll Text -> Get '[JSON] SourceFile
229−-- >
230−-- > myApi :: Proxy
231−-- > myApi = Proxy
232−--
233−-- > getSourceFile :: [Text] -> ClientM SourceFile
234−-- > getSourceFile = client myApi
235−-- > -- then you can use "getSourceFile" to query that endpoint
236−instance (KnownSymbol capture, ToHttpApiData a, HasClient m sublayout)
237− => HasClient m (CaptureAll capture a :> sublayout) where
238−
239− type Client m (CaptureAll capture a :> sublayout) =
240− [a] -> Client m sublayout
241−
242− clientWithRoute pm Proxy req vals =
243− clientWithRoute pm (Proxy :: Proxy sublayout)
244− (foldl' (flip appendToPath) req ps)
245−
246− where ps = map toEncodedUrlPiece vals
247−
248− hoistClientMonad pm _ f cl = \as ->
249− hoistClientMonad pm (Proxy :: Proxy sublayout) f (cl as)
250−
251−instance {-# OVERLAPPABLE #-}
252− -- Note [Non-Empty Content Types]
253− ( RunClient m, MimeUnrender ct a, ReflectMethod method, cts' ~ (ct ': cts)
254− , KnownNat status
255− ) => HasClient m (Verb method status cts' a) where
256− type Client m (Verb method status cts' a) = m a
257− clientWithRoute _pm Proxy req = do
258− response <- runRequestAcceptStatus (Just [status]) req
259− { requestAccept = fromList $ toList accept
260− , requestMethod = method
261− }
262− response `decodedAs` (Proxy :: Proxy ct)
263− where
264− accept = contentTypes (Proxy :: Proxy ct)
265− method = reflectMethod (Proxy :: Proxy method)
266− status = statusFromNat (Proxy :: Proxy status)
267−
268− hoistClientMonad _ _ f ma = f ma
269−
270−instance {-# OVERLAPPING #-}
271− ( RunClient m, ReflectMethod method, KnownNat status
272− ) => HasClient m (Verb method status cts NoContent) where
273− type Client m (Verb method status cts NoContent)
274− = m NoContent
275− clientWithRoute _pm Proxy req = do
276− _response <- runRequestAcceptStatus (Just [status]) req { requestMethod = method }
277− return NoContent
278− where method = reflectMethod (Proxy :: Proxy method)
279− status = statusFromNat (Proxy :: Proxy status)
280−
281− hoistClientMonad _ _ f ma = f ma
282−
283−instance (RunClient m, ReflectMethod method) =>
284− HasClient m (NoContentVerb method) where
285− type Client m (NoContentVerb method)
286− = m NoContent
287− clientWithRoute _pm Proxy req = do
288− _response <- runRequest req { requestMethod = method }
289− return NoContent
290− where method = reflectMethod (Proxy :: Proxy method)
291−
292− hoistClientMonad _ _ f ma = f ma
293−
294−instance {-# OVERLAPPING #-}
295− -- Note [Non-Empty Content Types]
296− ( RunClient m, MimeUnrender ct a, BuildHeadersTo ls, KnownNat status
297− , ReflectMethod method, cts' ~ (ct ': cts)
298− ) => HasClient m (Verb method status cts' (Headers ls a)) where
299− type Client m (Verb method status cts' (Headers ls a))
300− = m (Headers ls a)
301− clientWithRoute _pm Proxy req = do
302− response <- runRequestAcceptStatus (Just [status]) req
303− { requestMethod = method
304− , requestAccept = fromList $ toList accept
305− }
306− val <- response `decodedAs` (Proxy :: Proxy ct)
307− return $ Headers { getResponse = val
308− , getHeadersHList = buildHeadersTo . toList $ responseHeaders response
309− }
310− where
311− method = reflectMethod (Proxy :: Proxy method)
312− accept = contentTypes (Proxy :: Proxy ct)
313− status = statusFromNat (Proxy :: Proxy status)
314−
315− hoistClientMonad _ _ f ma = f ma
316−
317−instance {-# OVERLAPPING #-}
318− ( RunClient m, BuildHeadersTo ls, ReflectMethod method, KnownNat status
319− ) => HasClient m (Verb method status cts (Headers ls NoContent)) where
320− type Client m (Verb method status cts (Headers ls NoContent))
321− = m (Headers ls NoContent)
322− clientWithRoute _pm Proxy req = do
323− response <- runRequestAcceptStatus (Just [status]) req { requestMethod = method }
324− return $ Headers { getResponse = NoContent
325− , getHeadersHList = buildHeadersTo . toList $ responseHeaders response
326− }
327− where
328− method = reflectMethod (Proxy :: Proxy method)
329− status = statusFromNat (Proxy :: Proxy status)
330−
331− hoistClientMonad _ _ f ma = f ma
332−
333−data ClientParseError = ClientParseError MediaType String | ClientStatusMismatch | ClientNoMatchingStatus
334− deriving (Eq, Show)
335−
336−class UnrenderResponse (cts :: [*]) (a :: *) where
337− unrenderResponse :: Seq.Seq H.Header -> BL.ByteString -> Proxy cts
338− -> [Either (MediaType, String) a]
339−
340−instance {-# OVERLAPPABLE #-} AllMimeUnrender cts a => UnrenderResponse cts a where
341− unrenderResponse _ body = map parse . allMimeUnrender
342− where parse (mediaType, parser) = left ((,) mediaType) (parser body)
343−
344−instance {-# OVERLAPPING #-} forall cts a h . (UnrenderResponse cts a, BuildHeadersTo h)
345− => UnrenderResponse cts (Headers h a) where
346− unrenderResponse hs body = (map . fmap) setHeaders . unrenderResponse hs body
347− where
348− setHeaders :: a -> Headers h a
349− setHeaders x = Headers x (buildHeadersTo (toList hs))
350−
351−instance {-# OVERLAPPING #-} UnrenderResponse cts a
352− => UnrenderResponse cts (WithStatus n a) where
353− unrenderResponse hs body = (map . fmap) WithStatus . unrenderResponse hs body
354−
355−instance {-# OVERLAPPING #-}
356− ( RunClient m,
357− contentTypes ~ (contentType ': otherContentTypes),
358− -- ('otherContentTypes' should be '_', but even -XPartialTypeSignatures does not seem
359− -- allow this in instance types as of 8.8.3.)
360− as ~ (a ': as'),
361− AllMime contentTypes,
362− ReflectMethod method,
363− All (UnrenderResponse contentTypes) as,
364− All HasStatus as, HasStatuses as',
365− Unique (Statuses as)
366− ) =>
367− HasClient m (UVerb method contentTypes as)
368− where
369− type Client m (UVerb method contentTypes as) = m (Union as)
370−
371− clientWithRoute _ _ request = do
372− let accept = Seq.fromList . allMime $ Proxy @contentTypes
373− -- offering to accept all mime types listed in the api gives best compatibility. eg.,
374− -- we might not own the server implementation, and the server may choose to support
375− -- only part of the api.
376−
377− method = reflectMethod $ Proxy @method
378− acceptStatus = statuses (Proxy @as)
379− response <- runRequestAcceptStatus (Just acceptStatus) request {requestMethod = method, requestAccept = accept}
380− responseContentType <- checkContentTypeHeader response
381− unless (any (matches responseContentType) accept) $ do
382− throwClientError $ UnsupportedContentType responseContentType response
383−
384− let status = responseStatusCode response
385− body = responseBody response
386− headers = responseHeaders response
387− res = tryParsers status $ mimeUnrenders (Proxy @contentTypes) headers body
388− case res of
389− Left errors -> throwClientError $ DecodeFailure (T.pack (show errors)) response
390− Right x -> return x
391− where
392− -- | Given a list of parsers of 'mkres', returns the first one that succeeds and all the
393− -- failures it encountered along the way
394− -- TODO; better name, rewrite haddocs.
395− tryParsers :: forall xs. All HasStatus xs => Status -> NP ([] :.: Either (MediaType, String)) xs -> Either [ClientParseError] (Union xs)
396− tryParsers _ Nil = Left [ClientNoMatchingStatus]
397− tryParsers status (Comp x :* xs)
398− | status == statusOf (Comp x) =
399− case partitionEithers x of
400− (err', []) -> (map (uncurry ClientParseError) err' ++) +++ S $ tryParsers status xs
401− (_, (res : _)) -> Right . inject . I $ res
402− | otherwise = -- no reason to parse in the first place. This ain't the one we're looking for
403− (ClientStatusMismatch :) +++ S $ tryParsers status xs
404−
405− -- | Given a list of types, parses the given response body as each type
406− mimeUnrenders ::
407− forall cts xs.
408− All (UnrenderResponse cts) xs =>
409− Proxy cts ->
410− Seq.Seq H.Header ->
411− BL.ByteString ->
412− NP ([] :.: Either (MediaType, String)) xs
413− mimeUnrenders ctp headers body = cpure_NP
414− (Proxy @(UnrenderResponse cts))
415− (Comp . unrenderResponse headers body $ ctp)
416−
417− hoistClientMonad _ _ nt s = nt s
418−
419−instance {-# OVERLAPPABLE #-}
420− ( RunStreamingClient m, MimeUnrender ct chunk, ReflectMethod method,
421− FramingUnrender framing, FromSourceIO chunk a
422− ) => HasClient m (Stream method status framing ct a) where
423−
424− type Client m (Stream method status framing ct a) = m a
425−
426− hoistClientMonad _ _ f ma = f ma
427−
428− clientWithRoute _pm Proxy req = withStreamingRequest req' $ \gres -> do
429− let mimeUnrender' = mimeUnrender (Proxy :: Proxy ct) :: BL.ByteString -> Either String chunk
430− framingUnrender' = framingUnrender (Proxy :: Proxy framing) mimeUnrender'
431− return $ fromSourceIO $ framingUnrender' $ responseBody gres
432− where
433− req' = req
434− { requestAccept = fromList [contentType (Proxy :: Proxy ct)]
435− , requestMethod = reflectMethod (Proxy :: Proxy method)
436− }
437−
438−instance {-# OVERLAPPING #-}
439− ( RunStreamingClient m, MimeUnrender ct chunk, ReflectMethod method,
440− FramingUnrender framing, FromSourceIO chunk a,
441− BuildHeadersTo hs
442− ) => HasClient m (Stream method status framing ct (Headers hs a)) where
443−
444− type Client m (Stream method status framing ct (Headers hs a)) = m (Headers hs a)
445−
446− hoistClientMonad _ _ f ma = f ma
447−
448− clientWithRoute _pm Proxy req = withStreamingRequest req' $ \gres -> do
449− let mimeUnrender' = mimeUnrender (Proxy :: Proxy ct) :: BL.ByteString -> Either String chunk
450− framingUnrender' = framingUnrender (Proxy :: Proxy framing) mimeUnrender'
451− val = fromSourceIO $ framingUnrender' $ responseBody gres
452− return $ Headers
453− { getResponse = val
454− , getHeadersHList = buildHeadersTo . toList $ responseHeaders gres
455− }
456−
457− where
458− req' = req
459− { requestAccept = fromList [contentType (Proxy :: Proxy ct)]
460− , requestMethod = reflectMethod (Proxy :: Proxy method)
461− }
462−
463−-- | If you use a 'Header' in one of your endpoints in your API,
464−-- the corresponding querying function will automatically take
465−-- an additional argument of the type specified by your 'Header',
466−-- wrapped in Maybe.
467−--
468−-- That function will take care of encoding this argument as Text
469−-- in the request headers.
470−--
471−-- All you need is for your type to have a 'ToHttpApiData' instance.
472−--
473−-- Example:
474−--
475−-- > newtype Referer = Referer { referrer :: Text }
476−-- > deriving (Eq, Show, Generic, ToHttpApiData)
477−-- >
478−-- > -- GET /view-my-referer
479−-- > type MyApi = "view-my-referer" :> Header "Referer" Referer :> Get '[JSON] Referer
480−-- >
481−-- > myApi :: Proxy MyApi
482−-- > myApi = Proxy
483−-- >
484−-- > viewReferer :: Maybe Referer -> ClientM Book
485−-- > viewReferer = client myApi
486−-- > -- then you can just use "viewRefer" to query that endpoint
487−-- > -- specifying Nothing or e.g Just "http://haskell.org/" as arguments
488−instance (KnownSymbol sym, ToHttpApiData a, HasClient m api, SBoolI (FoldRequired mods))
489− => HasClient m (Header' mods sym a :> api) where
490−
491− type Client m (Header' mods sym a :> api) =
492− RequiredArgument mods a -> Client m api
493−
494− clientWithRoute pm Proxy req mval =
495− clientWithRoute pm (Proxy :: Proxy api) $ foldRequiredArgument
496− (Proxy :: Proxy mods) add (maybe req add) mval
497− where
498− hname = fromString $ symbolVal (Proxy :: Proxy sym)
499−
500− add :: a -> Request
501− add value = addHeader hname value req
502−
503− hoistClientMonad pm _ f cl = \arg ->
504− hoistClientMonad pm (Proxy :: Proxy api) f (cl arg)
505−
506−-- | Using a 'HttpVersion' combinator in your API doesn't affect the client
507−-- functions.
508−instance HasClient m api
509− => HasClient m (HttpVersion :> api) where
510−
511− type Client m (HttpVersion :> api) =
512− Client m api
513−
514− clientWithRoute pm Proxy =
515− clientWithRoute pm (Proxy :: Proxy api)
516−
517− hoistClientMonad pm _ f cl = hoistClientMonad pm (Proxy :: Proxy api) f cl
518−
519−-- | Ignore @'Summary'@ in client functions.
520−instance HasClient m api => HasClient m (Summary desc :> api) where
521− type Client m (Summary desc :> api) = Client m api
522−
523− clientWithRoute pm _ = clientWithRoute pm (Proxy :: Proxy api)
524−
525− hoistClientMonad pm _ f cl = hoistClientMonad pm (Proxy :: Proxy api) f cl
526−
527−-- | Ignore @'Description'@ in client functions.
528−instance HasClient m api => HasClient m (Description desc :> api) where
529− type Client m (Description desc :> api) = Client m api
530−
531− clientWithRoute pm _ = clientWithRoute pm (Proxy :: Proxy api)
532−
533− hoistClientMonad pm _ f cl = hoistClientMonad pm (Proxy :: Proxy api) f cl
534−
535−-- | If you use a 'QueryParam' in one of your endpoints in your API,
536−-- the corresponding querying function will automatically take
537−-- an additional argument of the type specified by your 'QueryParam',
538−-- enclosed in Maybe.
539−--
540−-- If you give Nothing, nothing will be added to the query string.
541−--
542−-- If you give a non-'Nothing' value, this function will take care
543−-- of inserting a textual representation of this value in the query string.
544−--
545−-- You can control how values for your type are turned into
546−-- text by specifying a 'ToHttpApiData' instance for your type.
547−--
548−-- Example:
549−--
550−-- > type MyApi = "books" :> QueryParam "author" Text :> Get '[JSON] [Book]
551−-- >
552−-- > myApi :: Proxy MyApi
553−-- > myApi = Proxy
554−-- >
555−-- > getBooksBy :: Maybe Text -> ClientM [Book]
556−-- > getBooksBy = client myApi
557−-- > -- then you can just use "getBooksBy" to query that endpoint.
558−-- > -- 'getBooksBy Nothing' for all books
559−-- > -- 'getBooksBy (Just "Isaac Asimov")' to get all books by Isaac Asimov
560−instance (KnownSymbol sym, ToHttpApiData a, HasClient m api, SBoolI (FoldRequired mods))
561− => HasClient m (QueryParam' mods sym a :> api) where
562−
563− type Client m (QueryParam' mods sym a :> api) =
564− RequiredArgument mods a -> Client m api
565−
566− -- if mparam = Nothing, we don't add it to the query string
567− clientWithRoute pm Proxy req mparam =
568− clientWithRoute pm (Proxy :: Proxy api) $ foldRequiredArgument
569− (Proxy :: Proxy mods) add (maybe req add) mparam
570− where
571− add :: a -> Request
572− add param = appendToQueryString pname (Just $ encodeQueryParamValue param) req
573−
574− pname :: Text
575− pname = pack $ symbolVal (Proxy :: Proxy sym)
576−
577− hoistClientMonad pm _ f cl = \arg ->
578− hoistClientMonad pm (Proxy :: Proxy api) f (cl arg)
579−
580−-- | If you use a 'QueryParams' in one of your endpoints in your API,
581−-- the corresponding querying function will automatically take
582−-- an additional argument, a list of values of the type specified
583−-- by your 'QueryParams'.
584−--
585−-- If you give an empty list, nothing will be added to the query string.
586−--
587−-- Otherwise, this function will take care
588−-- of inserting a textual representation of your values in the query string,
589−-- under the same query string parameter name.
590−--
591−-- You can control how values for your type are turned into
592−-- text by specifying a 'ToHttpApiData' instance for your type.
593−--
594−-- Example:
595−--
596−-- > type MyApi = "books" :> QueryParams "authors" Text :> Get '[JSON] [Book]
597−-- >
598−-- > myApi :: Proxy MyApi
599−-- > myApi = Proxy
600−-- >
601−-- > getBooksBy :: [Text] -> ClientM [Book]
602−-- > getBooksBy = client myApi
603−-- > -- then you can just use "getBooksBy" to query that endpoint.
604−-- > -- 'getBooksBy []' for all books
605−-- > -- 'getBooksBy ["Isaac Asimov", "Robert A. Heinlein"]'
606−-- > -- to get all books by Asimov and Heinlein
607−instance (KnownSymbol sym, ToHttpApiData a, HasClient m api)
608− => HasClient m (QueryParams sym a :> api) where
609−
610− type Client m (QueryParams sym a :> api) =
611− [a] -> Client m api
612−
613− clientWithRoute pm Proxy req paramlist =
614− clientWithRoute pm (Proxy :: Proxy api)
615− (foldl' (\ req' -> maybe req' (flip (appendToQueryString pname) req' . Just))
616− req
617− paramlist'
618− )
619−
620− where pname = pack $ symbolVal (Proxy :: Proxy sym)
621− paramlist' = map (Just . encodeQueryParamValue) paramlist
622−
623− hoistClientMonad pm _ f cl = \as ->
624− hoistClientMonad pm (Proxy :: Proxy api) f (cl as)
625−
626−-- | If you use a 'QueryFlag' in one of your endpoints in your API,
627−-- the corresponding querying function will automatically take
628−-- an additional 'Bool' argument.
629−--
630−-- If you give 'False', nothing will be added to the query string.
631−--
632−-- Otherwise, this function will insert a value-less query string
633−-- parameter under the name associated to your 'QueryFlag'.
634−--
635−-- Example:
636−--
637−-- > type MyApi = "books" :> QueryFlag "published" :> Get '[JSON] [Book]
638−-- >
639−-- > myApi :: Proxy MyApi
640−-- > myApi = Proxy
641−-- >
642−-- > getBooks :: Bool -> ClientM [Book]
643−-- > getBooks = client myApi
644−-- > -- then you can just use "getBooks" to query that endpoint.
645−-- > -- 'getBooksBy False' for all books
646−-- > -- 'getBooksBy True' to only get _already published_ books
647−instance (KnownSymbol sym, HasClient m api)
648− => HasClient m (QueryFlag sym :> api) where
649−
650− type Client m (QueryFlag sym :> api) =
651− Bool -> Client m api
652−
653− clientWithRoute pm Proxy req flag =
654− clientWithRoute pm (Proxy :: Proxy api)
655− (if flag
656− then appendToQueryString paramname Nothing req
657− else req
658− )
659−
660− where paramname = pack $ symbolVal (Proxy :: Proxy sym)
661−
662− hoistClientMonad pm _ f cl = \b ->
663− hoistClientMonad pm (Proxy :: Proxy api) f (cl b)
664−
665−-- | Pick a 'Method' and specify where the server you want to query is. You get
666−-- back the full `Response`.
667−instance RunClient m => HasClient m Raw where
668− type Client m Raw
669− = H.Method -> m Response
670−
671− clientWithRoute :: Proxy m -> Proxy Raw -> Request -> Client m Raw
672− clientWithRoute _pm Proxy req httpMethod = do
673− runRequest req { requestMethod = httpMethod }
674−
675− hoistClientMonad _ _ f cl = \meth -> f (cl meth)
676−
677−-- | If you use a 'ReqBody' in one of your endpoints in your API,
678−-- the corresponding querying function will automatically take
679−-- an additional argument of the type specified by your 'ReqBody'.
680−-- That function will take care of encoding this argument as JSON and
681−-- of using it as the request body.
682−--
683−-- All you need is for your type to have a 'ToJSON' instance.
684−--
685−-- Example:
686−--
687−-- > type MyApi = "books" :> ReqBody '[JSON] Book :> Post '[JSON] Book
688−-- >
689−-- > myApi :: Proxy MyApi
690−-- > myApi = Proxy
691−-- >
692−-- > addBook :: Book -> ClientM Book
693−-- > addBook = client myApi
694−-- > -- then you can just use "addBook" to query that endpoint
695−instance (MimeRender ct a, HasClient m api)
696− => HasClient m (ReqBody' mods (ct ': cts) a :> api) where
697−
698− type Client m (ReqBody' mods (ct ': cts) a :> api) =
699− a -> Client m api
700−
701− clientWithRoute pm Proxy req body =
702− clientWithRoute pm (Proxy :: Proxy api)
703− (let ctProxy = Proxy :: Proxy ct
704− in setRequestBodyLBS (mimeRender ctProxy body)
705− -- We use first contentType from the Accept list
706− (contentType ctProxy)
707− req
708− )
709−
710− hoistClientMonad pm _ f cl = \a ->
711− hoistClientMonad pm (Proxy :: Proxy api) f (cl a)
712−
713−instance
714− ( HasClient m api, MimeRender ctype chunk, FramingRender framing, ToSourceIO chunk a
715− ) => HasClient m (StreamBody' mods framing ctype a :> api)
716− where
717−
718− type Client m (StreamBody' mods framing ctype a :> api) = a -> Client m api
719−
720− hoistClientMonad pm _ f cl = \a ->
721− hoistClientMonad pm (Proxy :: Proxy api) f (cl a)
722−
723− clientWithRoute pm Proxy req body
724− = clientWithRoute pm (Proxy :: Proxy api)
725− $ setRequestBody (RequestBodySource sourceIO) (contentType ctypeP) req
726− where
727− ctypeP = Proxy :: Proxy ctype
728− framingP = Proxy :: Proxy framing
729−
730− sourceIO = framingRender
731− framingP
732− (mimeRender ctypeP :: chunk -> BL.ByteString)
733− (toSourceIO body)
734−
735−-- | Make the querying function append @path@ to the request path.
736−instance (KnownSymbol path, HasClient m api) => HasClient m (path :> api) where
737− type Client m (path :> api) = Client m api
738−
739− clientWithRoute pm Proxy req =
740− clientWithRoute pm (Proxy :: Proxy api)
741− (appendToPath p req)
742−
743− where p = toEncodedUrlPiece $ pack $ symbolVal (Proxy :: Proxy path)
744−
745− hoistClientMonad pm _ f cl = hoistClientMonad pm (Proxy :: Proxy api) f cl
746−
747−instance HasClient m api => HasClient m (Vault :> api) where
748− type Client m (Vault :> api) = Client m api
749−
750− clientWithRoute pm Proxy req =
751− clientWithRoute pm (Proxy :: Proxy api) req
752−
753− hoistClientMonad pm _ f cl = hoistClientMonad pm (Proxy :: Proxy api) f cl
754−
755−instance HasClient m api => HasClient m (RemoteHost :> api) where
756− type Client m (RemoteHost :> api) = Client m api
757−
758− clientWithRoute pm Proxy req =
759− clientWithRoute pm (Proxy :: Proxy api) req
760−
761− hoistClientMonad pm _ f cl = hoistClientMonad pm (Proxy :: Proxy api) f cl
762−
763−instance HasClient m api => HasClient m (IsSecure :> api) where
764− type Client m (IsSecure :> api) = Client m api
765−
766− clientWithRoute pm Proxy req =
767− clientWithRoute pm (Proxy :: Proxy api) req
768−
769− hoistClientMonad pm _ f cl = hoistClientMonad pm (Proxy :: Proxy api) f cl
770−
771−instance HasClient m subapi =>
772− HasClient m (WithNamedContext name context subapi) where
773−
774− type Client m (WithNamedContext name context subapi) = Client m subapi
775− clientWithRoute pm Proxy = clientWithRoute pm (Proxy :: Proxy subapi)
776−
777− hoistClientMonad pm _ f cl = hoistClientMonad pm (Proxy :: Proxy subapi) f cl
778−
779−instance ( HasClient m api
780− ) => HasClient m (AuthProtect tag :> api) where
781− type Client m (AuthProtect tag :> api)
782− = AuthenticatedRequest (AuthProtect tag) -> Client m api
783−
784− clientWithRoute pm Proxy req (AuthenticatedRequest (val,func)) =
785− clientWithRoute pm (Proxy :: Proxy api) (func val req)
786−
787− hoistClientMonad pm _ f cl = \authreq ->
788− hoistClientMonad pm (Proxy :: Proxy api) f (cl authreq)
789−
790−-- | Ignore @'Fragment'@ in client functions.
791−-- See <https://ietf.org/rfc/rfc2616.html#section-15.1.3> for more details.
792−--
793−-- Example:
794−--
795−-- > type MyApi = "books" :> Fragment Text :> Get '[JSON] [Book]
796−-- >
797−-- > myApi :: Proxy MyApi
798−-- > myApi = Proxy
799−-- >
800−-- > getBooks :: ClientM [Book]
801−-- > getBooks = client myApi
802−-- > -- then you can just use "getBooksBy" to query that endpoint.
803−-- > -- 'getBooks' for all books.
804−instance (AtLeastOneFragment api, FragmentUnique (Fragment a :> api), HasClient m api
805− ) => HasClient m (Fragment a :> api) where
806−
807− type Client m (Fragment a :> api) = Client m api
808−
809− clientWithRoute pm _ = clientWithRoute pm (Proxy :: Proxy api)
810−
811− hoistClientMonad pm _ = hoistClientMonad pm (Proxy :: Proxy api)
812−
813−-- * Basic Authentication
814−
815−instance HasClient m api => HasClient m (BasicAuth realm usr :> api) where
816− type Client m (BasicAuth realm usr :> api) = BasicAuthData -> Client m api
817−
818− clientWithRoute pm Proxy req val =
819− clientWithRoute pm (Proxy :: Proxy api) (basicAuthReq val req)
820−
821− hoistClientMonad pm _ f cl = \bauth ->
822− hoistClientMonad pm (Proxy :: Proxy api) f (cl bauth)
823−
824−-- | A type that specifies that an API record contains a client implementation.
825−data AsClientT (m :: * -> *)
826−instance GenericMode (AsClientT m) where
827− type AsClientT m :- api = Client m api
828−
829−
830−type GClientConstraints api m =
831− ( GenericServant api (AsClientT m)
832− , Client m (ToServantApi api) ~ ToServant api (AsClientT m)
833− )
834−
835−class GClient (api :: * -> *) m where
836− gClientProof :: Dict (GClientConstraints api m)
837−
838−instance GClientConstraints api m => GClient api m where
839− gClientProof = Dict
840−
841−instance
842− ( forall n. GClient api n
843− , HasClient m (ToServantApi api)
844− , RunClient m
845− )
846− => HasClient m (NamedRoutes api) where
847− type Client m (NamedRoutes api) = api (AsClientT m)
848−
849− clientWithRoute :: Proxy m -> Proxy (NamedRoutes api) -> Request -> Client m (NamedRoutes api)
850− clientWithRoute pm _ request =
851− case gClientProof @api @m of
852− Dict -> fromServant $ clientWithRoute pm (Proxy @(ToServantApi api)) request
853−
854− hoistClientMonad
855− :: forall ma mb.
856− Proxy m
857− -> Proxy (NamedRoutes api)
858− -> (forall x. ma x -> mb x)
859− -> Client ma (NamedRoutes api)
860− -> Client mb (NamedRoutes api)
861− hoistClientMonad _ _ nat clientA =
862− case (gClientProof @api @ma, gClientProof @api @mb) of
863− (Dict, Dict) ->
864− fromServant @api @(AsClientT mb) $
865− hoistClientMonad @m @(ToServantApi api) @ma @mb Proxy Proxy nat $
866− toServant @api @(AsClientT ma) clientA
867−
868−infixl 1 //
869−infixl 2 /:
870−
871−-- | Helper to make code using records of clients more readable.
872−--
873−-- Can be mixed with (/:) for supplying arguments.
874−--
875−-- Example:
876−--
877−-- @
878−-- type Api = NamedRoutes RootApi
879−--
880−-- data RootApi mode = RootApi
881−-- { subApi :: mode :- NamedRoutes SubApi
882−-- , …
883−-- } deriving Generic
884−--
885−-- data SubApi mode = SubApi
886−-- { endpoint :: mode :- Get '[JSON] Person
887−-- , …
888−-- } deriving Generic
889−--
890−-- api :: Proxy API
891−-- api = Proxy
892−--
893−-- rootClient :: RootApi (AsClientT ClientM)
894−-- rootClient = client api
895−--
896−-- endpointClient :: ClientM Person
897−-- endpointClient = client // subApi // endpoint
898−-- @
899−(//) :: a -> (a -> b) -> b
900−x // f = f x
901−
902−-- | Convenience function for supplying arguments to client functions when
903−-- working with records of clients.
904−--
905−-- Intended to be used in conjunction with '(//)'.
906−--
907−-- Example:
908−--
909−-- @
910−-- type Api = NamedRoutes RootApi
911−--
912−-- data RootApi mode = RootApi
913−-- { subApi :: mode :- Capture "token" String :> NamedRoutes SubApi
914−-- , hello :: mode :- Capture "name" String :> Get '[JSON] String
915−-- , …
916−-- } deriving Generic
917−--
918−-- data SubApi mode = SubApi
919−-- { endpoint :: mode :- Get '[JSON] Person
920−-- , …
921−-- } deriving Generic
922−--
923−-- api :: Proxy API
924−-- api = Proxy
925−--
926−-- rootClient :: RootApi (AsClientT ClientM)
927−-- rootClient = client api
928−--
929−-- hello :: String -> ClientM String
930−-- hello name = rootClient // hello /: name
931−--
932−-- endpointClient :: ClientM Person
933−-- endpointClient = client // subApi /: "foobar123" // endpoint
934−-- @
935−(/:) :: (a -> b -> c) -> b -> a -> c
936−(/:) = flip
937−
938−
939−{- Note [Non-Empty Content Types]
940−~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
941−Rather than have
942−
943− instance (..., cts' ~ (ct ': cts)) => ... cts' ...
944−
945−It may seem to make more sense to have:
946−
947− instance (...) => ... (ct ': cts) ...
948−
949−But this means that if another instance exists that does *not* require
950−non-empty lists, but is otherwise more specific, no instance will be overall
951−more specific. This in turn generally means adding yet another instance (one
952−for empty and one for non-empty lists).
953−-}
954−
955−-------------------------------------------------------------------------------
956−-- helpers
957−-------------------------------------------------------------------------------
958−
959−checkContentTypeHeader :: RunClient m => Response -> m MediaType
960−checkContentTypeHeader response =
961− case lookup "Content-Type" $ toList $ responseHeaders response of
962− Nothing -> return $ "application" Media.// "octet-stream"
963− Just t -> case parseAccept t of
964− Nothing -> throwClientError $ InvalidContentTypeHeader response
965− Just t' -> return t'
966−
967−decodedAs :: forall ct a m. (MimeUnrender ct a, RunClient m)
968− => Response -> Proxy ct -> m a
969−decodedAs response ct = do
970− responseContentType <- checkContentTypeHeader response
971− unless (any (matches responseContentType) accept) $
972− throwClientError $ UnsupportedContentType responseContentType response
973− case mimeUnrender ct $ responseBody response of
974− Left err -> throwClientError $ DecodeFailure (T.pack err) response
975− Right val -> return val
976− where
977− accept = toList $ contentTypes ct
978−
979−-------------------------------------------------------------------------------
980−-- Custom type errors
981−-------------------------------------------------------------------------------
982−
983−-- Erroring instance for HasClient' when a combinator is not fully applied
984−instance (RunClient m, TypeError (PartialApplication HasClient arr)) => HasClient m ((arr :: a -> b) :> sub)
985− where
986− type Client m (arr :> sub) = TypeError (PartialApplication HasClient arr)
987− clientWithRoute _ _ _ = error "unreachable"
988− hoistClientMonad _ _ _ _ = error "unreachable"
989−
990−-- Erroring instances for 'HasClient' for unknown API combinators
991−instance {-# OVERLAPPABLE #-} (RunClient m, TypeError (NoInstanceForSub (HasClient m) ty)) => HasClient m (ty :> sub)
992−
993−instance {-# OVERLAPPABLE #-} (RunClient m, TypeError (NoInstanceFor (HasClient m api))) => HasClient m api