@@ -1,36 +1,24 @@
1+{-# LANGUAGE MultiWayIf #-}
12module Servant.QuickCheck.Internal.Predicates where
23
3−import Control.Exception (catch, throw)
4−import Control.Monad (liftM2, unless, when)
4+import Control.Monad
55import Data.Aeson (Object, decode)
6−import Data.Bifunctor (first)
6+import Data.Bifunctor (Bifunctor (..))
77import qualified Data.ByteString as SBS
88import qualified Data.ByteString.Char8 as SBSC
99import qualified Data.ByteString.Lazy as LBS
10−import Data.CaseInsensitive (foldCase, foldedCase, mk)
10+import Data.CaseInsensitive (mk)
1111import Data.Either (isRight)
1212import Data.List.Split (wordsBy)
13−import Data.Maybe (fromMaybe, isJust)
14−import Data.Semigroup (Semigroup (..))
15−import qualified Data.Text as T
16−import Data.Time (UTCTime, defaultTimeLocale, parseTimeM,
17− rfc822DateFormat)
13+import Data.Maybe (isJust)
14+import Data.Monoid ((<>))
15+import Data.Text (Text)
1816import GHC.Generics (Generic)
1917import Network.HTTP.Client (Manager, Request, Response, httpLbs,
20− method, parseRequest, requestHeaders,
21− responseBody, responseHeaders,
18+ method, responseBody, responseHeaders,
2219 responseStatus)
23−import Network.HTTP.Media (matchAccept)
2420import Network.HTTP.Types (methodGet, methodHead, parseMethod,
25− renderStdMethod, status100, status200,
26− status201, status300, status401,
27− status405, status500)
28−import Prelude.Compat
29−import System.Clock (Clock (Monotonic), diffTimeSpec,
30− getTime, toNanoSecs)
31−
32−import Servant.QuickCheck.Internal.ErrorTypes
33−
21+ status401, renderStdMethod, status405, status500)
3422
3523-- | [__Best Practice__]
3624--
@@ -39,27 +27,8 @@ import Servant.QuickCheck.Internal.ErrorTypes
3927-- indication of how to proceed or what went wrong.
4028--
4129-- This function checks that the response code is not 500.
42−--
43−-- /Since 0.0.0.0/
44−not500 :: ResponsePredicate
45−not500 = ResponsePredicate $ \resp ->
46− when (responseStatus resp == status500) $ throw $ PredicateFailure "not500" Nothing resp
47−
48−-- | [__Optional__]
49−--
50−-- This function checks that the response from the server does not take longer
51−-- than the specified number of nanoseconds.
52−--
53−-- /Since 0.0.2.1/
54−notLongerThan :: Integer -> RequestPredicate
55−notLongerThan maxAllowed
56− = RequestPredicate $ \req mgr -> do
57− start <- getTime Monotonic
58− resp <- httpLbs req mgr
59− end <- getTime Monotonic
60− when (toNanoSecs (end `diffTimeSpec` start) > maxAllowed) $
61− throw $ PredicateFailure "notLongerThan" (Just req) resp
62− return []
30+not500 :: ResponsePredicate Text Bool
31+not500 = ResponsePredicate "not500" (\resp -> not $ responseStatus resp == status500)
6332
6433-- | [__Best Practice__]
6534--
@@ -80,17 +49,11 @@ notLongerThan maxAllowed
8049--
8150-- * JSON Grammar: <https://tools.ietf.org/html/rfc7159#section-2 RFC 7159 Section 2>
8251-- * JSON Grammar: <https://tools.ietf.org/html/rfc4627#section-2 RFC 4627 Section 2>
83−--
84−-- /Since 0.0.0.0/
85−onlyJsonObjects :: ResponsePredicate
52+onlyJsonObjects :: ResponsePredicate Text Bool
8653onlyJsonObjects
87− = ResponsePredicate (\resp -> do
88− case lookup "content-type" (first foldedCase <$> responseHeaders resp) of
89− Nothing -> return ()
90− Just ctype -> when ("application/json" `SBS.isPrefixOf` ctype) $ do
91− case (decode (responseBody resp) :: Maybe Object) of
92− Nothing -> throw $ PredicateFailure "onlyJsonObjects" Nothing resp
93− Just _ -> return ())
54+ = ResponsePredicate "onlyJsonObjects" (\resp -> case decode (responseBody resp) of
55+ Nothing -> False
56+ Just (_ :: Object) -> True)
9457
9558-- | __Optional__
9659--
@@ -109,61 +72,23 @@ onlyJsonObjects
10972--
11073-- * 201 Created: <https://tools.ietf.org/html/rfc7231#section-6.3.2 RFC 7231 Section 6.3.2>
11174-- * Location header: <https://tools.ietf.org/html/rfc7231#section-7.1.2 RFC 7231 Section 7.1.2>
112−--
113−-- /Since 0.0.0.0/
114−createContainsValidLocation :: RequestPredicate
115−createContainsValidLocation
116− = RequestPredicate $ \req mgr -> do
117− let n = "createContainsValidLocation"
118− resp <- httpLbs req mgr
119− if responseStatus resp == status201
120− then case lookup "Location" $ responseHeaders resp of
121− Nothing -> throw $ PredicateFailure n (Just req) resp
122− Just l -> case parseRequest $ SBSC.unpack l of
123− Nothing -> throw $ PredicateFailure n (Just req) resp
124− Just x -> do
125− resp2 <- httpLbs x mgr
126− status2XX (Just req) resp2 n
127− return [resp, resp2]
128− else return [resp]
129−
130−-- | [__Optional__]
131−--
132−-- The @Last-Modified@ header represents the time a resource was last
133−-- modified. It is used to drive caching and conditional requests.
134−--
135−-- When using this mechanism, the server adds the @Last-Modified@ header to
136−-- responses. Clients may then make requests with the @If-Modified-Since@
137−-- header to conditionally request resources. If the resource has not
138−-- changed since that date, the server responds with a status code of 304
139−-- (@Not Modified@) without a response body.
140−--
141−-- The @Last-Modified@ header can also be used in conjunction with the
142−-- @If-Unmodified-Since@ header to drive optimistic concurrency.
143−--
144−-- The @Last-Modified@ date must be in RFC 822 format.
145−--
146−-- __References__:
147−--
148−-- * 304 Not Modified: <https://tools.ietf.org/html/rfc7232#section-4.1 RFC 7232 Section 4.1>
149−-- * Last-Modified header: <https://tools.ietf.org/html/rfc7232#section-2.2 RFC 7232 Section 2.2>
150−-- * If-Modified-Since header: <https://tools.ietf.org/html/rfc7232#section-3.3 RFC 7232 Section 3.3>
151−-- * If-Unmodified-Since header: <https://tools.ietf.org/html/rfc7232#section-3.4 RFC 7232 Section 3.4>
152−-- * Date format: <https://tools.ietf.org/html/rfc2616#section-3.3 RFC 2616 Section 3.3>
153−--
154−-- /Since 0.0.2.1/
155−getsHaveLastModifiedHeader :: RequestPredicate
156−getsHaveLastModifiedHeader
157− = RequestPredicate $ \req mgr ->
158− if (method req == methodGet)
159− then do
160− resp <- httpLbs req mgr
161− unless (hasValidHeader "Last-Modified" isRFC822Date resp) $ do
162− throw $ PredicateFailure "getsHaveLastModifiedHeader" (Just req) resp
163− return [resp]
164− else return []
75+{-createContainsValidLocation :: RequestPredicate Text Bool-}
76+{-createContainsValidLocation-}
77+ {-= RequestPredicate-}
78+ {-{ reqPredName = "createContainsValidLocation"-}
79+ {-, reqResps = \req mg -> do-}
80+ {-resp <- httpLbs mgr req-}
81+ {-if responseStatus resp == status201-}
82+ {-then case lookup "Location" $ responseHeaders resp of-}
83+ {-Nothing -> return []-}
84+ {-Just l -> if-}
16585
86+{-
87+getsHaveLastModifiedHeader :: ResponsePredicate Text Bool
88+getsHaveLastModifiedHeader
89+ = ResponsePredicate "getsHaveLastModifiedHeader" (\resp ->
16690
91+-}
16792
16893-- | [__RFC Compliance__]
16994--
@@ -175,61 +100,51 @@ getsHaveLastModifiedHeader
175100-- This function checks that every @405 Method Not Allowed@ response contains
176101-- an @Allow@ header with a list of standard HTTP methods.
177102--
178−-- Note that 'servant' itself does not currently set the @Allow@ headers.
179−--
180103-- __References__:
181104--
182105-- * @Allow@ header: <https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html RFC 2616 Section 14.7>
183106-- * Status 405: <https://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html RFC 2616 Section 10.4.6>
184−-- * Servant Allow header issue: <https://github.com/haskell-servant/servant/issues/489 Issue #489>
185−--
186−-- /Since 0.0.0.0/
187−notAllowedContainsAllowHeader :: RequestPredicate
107+notAllowedContainsAllowHeader :: RequestPredicate Text Bool
188108notAllowedContainsAllowHeader
189− = RequestPredicate $ \req mgr -> do
190− let reqs = [ req { method = renderStdMethod m } | m <- [minBound .. maxBound]
191− , renderStdMethod m /= method req ]
192− resp <- mapM (flip httpLbs mgr) reqs
193−
194− case filter pred' (zip reqs resp) of
195− (x:_) -> throw $ PredicateFailure "notAllowedContainsAllowHeader" (Just $ fst x) (snd x)
196− [] -> return resp
109+ = RequestPredicate
110+ { reqPredName = "notAllowedContainsAllowHeader"
111+ , reqResps = \req mgr -> do
112+ resp <- mapM (flip httpLbs mgr) $ [ req { method = renderStdMethod m }
113+ | m <- [minBound .. maxBound ]
114+ , renderStdMethod m /= method req ]
115+ return (all pred' resp, resp)
116+ }
197117 where
198− pred' (_, resp) = responseStatus resp == status405 && not (hasValidHeader "Allow" go resp)
118+ pred' resp = responseStatus resp /= status405 || hasValidHeader "Allow" go resp
199119 where
200120 go x = all (\y -> isRight $ parseMethod $ SBSC.pack y)
201121 $ wordsBy (`elem` (", " :: [Char])) (SBSC.unpack x)
202122
203−
204−-- | [__RFC Compliance__]
205−--
206−-- When a request contains an @Accept@ header, the server must either return
123+ {-
124+-- | When a request contains an @Accept@ header, the server must either return
207125-- content in one of the requested representations, or respond with @406 Not
208126-- Acceptable@.
209127--
210128-- This function checks that every *successful* response has a @Content-Type@
211−-- header that matches the @Accept@ header. It does *not* check that the server
212−-- matches the quality descriptions of the @Accept@ header correctly.
129+-- header that matches the @Accept@ header.
213130--
214131-- __References__:
215132--
216133-- * @Accept@ header: <https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html RFC 2616 Section 14.1>
217−--
218−-- /Since 0.0.0.0/
219−honoursAcceptHeader :: RequestPredicate
134+honoursAcceptHeader :: RequestPredicate b Bool
220135honoursAcceptHeader
221− = RequestPredicate $ \req mgr -> do
136+ = RequestPredicate name (ResponsePredicate name $ \req mgr -> do
137+
222138 resp <- httpLbs req mgr
223139 let scode = responseStatus resp
224− sctype = lookup "Content-Type" $ responseHeaders resp
225− sacc = fromMaybe "*/*" $ lookup "Accept" (requestHeaders req)
226− if status100 < scode && scode < status300
227− then if isJust $ sctype >>= \x -> matchAccept [x] sacc
228− then throw $ PredicateFailure "honoursAcceptHeader" (Just req) resp
229− else return [resp]
230− else return [resp]
231−
140+ sctype = maybeToList $ lookup "Content-Type" $ responseHeaders resp
141+ sacc = fromMaybe "*/*" $ lookup "Accept" $ requestHeaders req
142+ if 100 < scode && scode < 300
143+ then isJust matchAccept sacc sctype
144+ else True)
145+ where name = "honoursAcceptHeader"
232146
147+-}
233148-- | [__Best Practice__]
234149--
235150-- Whether or not a representation should be cached, it is good practice to
@@ -242,34 +157,32 @@ honoursAcceptHeader
242157-- __References__:
243158--
244159-- * @Cache-Control@ header: <https://tools.ietf.org/html/rfc7234#section-5.2 RFC 7234 Section 5.2>
245−--
246−-- /Since 0.0.0.0/
247−getsHaveCacheControlHeader :: RequestPredicate
160+getsHaveCacheControlHeader :: RequestPredicate Text Bool
248161getsHaveCacheControlHeader
249− = RequestPredicate $ \req mgr ->
250− if (method req == methodGet)
251− then do
252− resp <- httpLbs req mgr
253− unless (hasValidHeader "Cache-Control" (const True) resp) $ do
254− throw $ PredicateFailure "getsHaveCacheControlHeader" (Just req) resp
255− return [resp]
256− else return []
162+ = RequestPredicate
163+ { reqPredName = "getsHaveCacheControlHeader"
164+ , reqResps = \req mgr -> if method req == methodGet
165+ then do
166+ resp <- httpLbs req mgr
167+ let good = isJust $ lookup "Cache-Control" $ responseHeaders resp
168+ return (good, [resp])
169+ else return (True, [])
170+ }
257171
258172-- | [__Best Practice__]
259173--
260174-- Like 'getsHaveCacheControlHeader', but for @HEAD@ requests.
261−--
262−-- /Since 0.0.0.0/
263−headsHaveCacheControlHeader :: RequestPredicate
175+headsHaveCacheControlHeader :: RequestPredicate Text Bool
264176headsHaveCacheControlHeader
265− = RequestPredicate $ \req mgr ->
266− if (method req == methodHead)
267− then do
268− resp <- httpLbs req mgr
269− unless (hasValidHeader "Cache-Control" (const True) resp) $
270− throw $ PredicateFailure "headsHaveCacheControlHeader" (Just req) resp
271− return [resp]
272− else return []
177+ = RequestPredicate
178+ { reqPredName = "headsHaveCacheControlHeader"
179+ , reqResps = \req mgr -> if method req == methodHead
180+ then do
181+ resp <- httpLbs req mgr
182+ let good = isJust $ lookup "Cache-Control" $ responseHeaders resp
183+ return (good, [resp])
184+ else return (True, [])
185+ }
273186{-
274187-- |
275188--
@@ -329,37 +242,12 @@ linkHeadersAreValid
329242-- __References__:
330243--
331244-- * @WWW-Authenticate@ header: <https://tools.ietf.org/html/rfc7235#section-4.1 RFC 7235 Section 4.1>
332−--
333−-- /Since 0.0.0.0/
334−unauthorizedContainsWWWAuthenticate :: ResponsePredicate
245+unauthorizedContainsWWWAuthenticate :: ResponsePredicate Text Bool
335246unauthorizedContainsWWWAuthenticate
336− = ResponsePredicate $ \resp ->
247+ = ResponsePredicate "unauthorizedContainsWWWAuthenticate" (\resp ->
337248 if responseStatus resp == status401
338− then unless (hasValidHeader "WWW-Authenticate" (const True) resp) $
339− throw $ PredicateFailure "unauthorizedContainsWWWAuthenticate" Nothing resp
340− else return ()
341−
342−
343−-- | [__RFC Compliance__]
344−--
345−-- [An HTML] document will start with exactly this string: <!DOCTYPE html>
346−--
347−-- This function checks that HTML documents (those with `Content-Type: text/html...`)
348−-- include a DOCTYPE declaration at the top. We do not enforce capital case for the string `DOCTYPE`.
349−--
350−-- __References__:
351−--
352−-- * HTML5 Doctype: <https://tools.ietf.org/html/rfc7992#section-6.1 RFC 7992 Section 6.1>
353−-- /Since 0.3.0.0/
354−htmlIncludesDoctype :: ResponsePredicate
355−htmlIncludesDoctype
356− = ResponsePredicate $ \resp ->
357− if hasValidHeader "Content-Type" (SBS.isPrefixOf . foldCase $ "text/html") resp
358− then do
359− let htmlContent = foldCase . LBS.take 20 $ responseBody resp
360− unless (LBS.isPrefixOf (foldCase "<!doctype html>") htmlContent) $
361− throw $ PredicateFailure "htmlIncludesDoctype" Nothing resp
362− else return ()
249+ then hasValidHeader "WWW-Authenticate" (const True) resp
250+ else True)
363251
364252-- * Predicate logic
365253
@@ -369,77 +257,76 @@ htmlIncludesDoctype
369257--
370258-- Still, this is all kind of ugly.
371259
372−-- | A predicate that depends only on the response.
373−--
374−-- /Since 0.0.0.0/
375−newtype ResponsePredicate = ResponsePredicate
376− { getResponsePredicate :: Response LBS.ByteString -> IO ()
377− } deriving (Generic)
260+data ResponsePredicate n r = ResponsePredicate
261+ { respPredName :: n
262+ , respPred :: Response LBS.ByteString -> r
263+ } deriving (Functor, Generic)
378264
379−instance Semigroup ResponsePredicate where
380− ResponsePredicate a <> ResponsePredicate b = ResponsePredicate $ \x -> a x >> b x
265+instance Bifunctor ResponsePredicate where
266+ first f (ResponsePredicate a b) = ResponsePredicate (f a) b
267+ second = fmap
381268
382−instance Monoid ResponsePredicate where
383− mempty = ResponsePredicate $ const $ return ()
384− mappend = (<>)
269+instance (Monoid n, Monoid r) => Monoid (ResponsePredicate n r) where
270+ mempty = ResponsePredicate mempty mempty
271+ a `mappend` b = ResponsePredicate
272+ { respPredName = respPredName a <> respPredName b
273+ , respPred = respPred a <> respPred b
274+ }
385275
386−-- | A predicate that depends on both the request and the response.
387−--
388−-- /Since 0.0.0.0/
389−newtype RequestPredicate = RequestPredicate
390− { getRequestPredicate :: Request -> Manager -> IO [Response LBS.ByteString]
391− } deriving (Generic)
276+data RequestPredicate n r = RequestPredicate
277+ { reqPredName :: n
278+ , reqResps :: Request -> Manager -> IO (r, [Response LBS.ByteString])
279+ } deriving (Generic, Functor)
392280
393−-- TODO: This isn't actually a monoid
394−instance Monoid RequestPredicate where
395− mempty = RequestPredicate (\r m -> httpLbs r m >>= \x -> return ([x]))
396− mappend = (<>)
281+instance Bifunctor RequestPredicate where
282+ first f (RequestPredicate a b) = RequestPredicate (f a) b
283+ second = fmap
397284
398285-- TODO: This isn't actually a monoid
399−instance Semigroup RequestPredicate where
400− RequestPredicate a <> RequestPredicate b = RequestPredicate $ \r mgr ->
401− liftM2 (<>) (a r mgr) (b r mgr)
402−
403−-- | A set of predicates. Construct one with 'mempty' and '<%>'.
404−data Predicates = Predicates
405− { requestPredicates :: RequestPredicate
406− , responsePredicates :: ResponsePredicate
407− } deriving (Generic)
286+instance (Monoid n, Monoid r) => Monoid (RequestPredicate n r) where
287+ mempty = RequestPredicate mempty (\r m -> httpLbs r m >>= \x -> return (mempty, [x]))
288+ a `mappend` b = RequestPredicate
289+ { reqPredName = reqPredName a <> reqPredName b
290+ , reqResps = \x m -> liftM2 (<>) (reqResps a x m) (reqResps b x m)
291+ }
292+
293+data Predicates n r = Predicates
294+ { reqPreds :: RequestPredicate n r
295+ , respPreds :: ResponsePredicate n r
296+ } deriving (Generic, Functor)
297+
298+instance (Monoid n, Monoid r) => Monoid (Predicates n r) where
299+ mempty = Predicates mempty mempty
300+ a `mappend` b = Predicates (reqPreds a <> reqPreds b) (respPreds a <> respPreds b)
408301
409−instance Semigroup Predicates where
410− a <> b = Predicates (requestPredicates a <> requestPredicates b)
411− (responsePredicates a <> responsePredicates b)
412302
413−instance Monoid Predicates where
414− mempty = Predicates mempty mempty
415− mappend = (<>)
416303
417304class JoinPreds a where
418− joinPreds :: a -> Predicates -> Predicates
305+ joinPreds :: a -> Predicates [Text] [Text] -> Predicates [Text] [Text]
419306
420−instance JoinPreds (RequestPredicate ) where
421− joinPreds p (Predicates x y) = Predicates (p <> x) y
307+instance JoinPreds (RequestPredicate Text Bool) where
308+ joinPreds p (Predicates x y) = Predicates (go <> x) y
309+ where go = let p' = first return p
310+ in fmap (\z -> if z then [] else reqPredName p') p'
311+
312+instance JoinPreds (ResponsePredicate Text Bool) where
313+ joinPreds p (Predicates x y) = Predicates x (go <> y)
314+ where go = let p' = first return p
315+ in fmap (\z -> if z then [] else respPredName p') p'
422316
423−instance JoinPreds (ResponsePredicate ) where
424− joinPreds p (Predicates x y) = Predicates x (p <> y)
425317
426318-- | Adds a new predicate (either `ResponsePredicate` or `RequestPredicate`) to
427319-- the existing predicates.
428320--
429321-- > not500 <%> onlyJsonObjects <%> empty
430−--
431−-- /Since 0.0.0.0/
432−(<%>) :: JoinPreds a => a -> Predicates -> Predicates
322+(<%>) :: JoinPreds a => a -> Predicates [Text] [Text] -> Predicates [Text] [Text]
433323(<%>) = joinPreds
434324infixr 6 <%>
435325
436−finishPredicates :: Predicates -> Request -> Manager -> IO (Maybe PredicateFailure)
437−finishPredicates p req mgr = go `catch` \(e :: PredicateFailure) -> return $ Just e
438− where
439− go = do
440− resps <- getRequestPredicate (requestPredicates p) req mgr
441− mapM_ (getResponsePredicate $ responsePredicates p) resps
442− return Nothing
326+finishPredicates :: Predicates [Text] [Text] -> Request -> Manager -> IO [Text]
327+finishPredicates p req mgr = do
328+ (soFar, resps) <- reqResps (reqPreds p) req mgr
329+ return $ soFar <> mconcat [respPred (respPreds p) r | r <- resps]
443330
444331-- * helpers
445332
@@ -447,15 +334,3 @@ hasValidHeader :: SBS.ByteString -> (SBS.ByteString -> Bool) -> Response b -> Bo
447334hasValidHeader hdr p r = case lookup (mk hdr) (responseHeaders r) of
448335 Nothing -> False
449336 Just v -> p v
450−
451−isRFC822Date :: SBS.ByteString -> Bool
452−isRFC822Date s
453− = case parseTimeM True defaultTimeLocale rfc822DateFormat (SBSC.unpack s) of
454− Nothing -> False
455− Just (_ :: UTCTime) -> True
456−
457−status2XX :: Monad m => Maybe Request -> Response LBS.ByteString -> T.Text -> m ()
458−status2XX mreq resp t
459− | status200 <= responseStatus resp && responseStatus resp < status300
460− = return ()
461− | otherwise = throw $ PredicateFailure t mreq resp