@@ -1,24 +1,36 @@
1−{-# LANGUAGE MultiWayIf #-}
2module Servant.QuickCheck.Internal.Predicates where
1module Servant.QuickCheck.Internal.Predicates where
4−import Control.Monad
3+import Control.Exception (catch, throw)
4+import Control.Monad (liftM2, unless, when)
5import Data.Aeson (Object, decode)
5import Data.Aeson (Object, decode)
6−import Data.Bifunctor (Bifunctor (..))
6+import Data.Bifunctor (first)
7import qualified Data.ByteString as SBS
7import qualified Data.ByteString as SBS
8import qualified Data.ByteString.Char8 as SBSC
8import qualified Data.ByteString.Char8 as SBSC
9import qualified Data.ByteString.Lazy as LBS
9import qualified Data.ByteString.Lazy as LBS
10−import Data.CaseInsensitive (mk)
10+import Data.CaseInsensitive (foldCase, foldedCase, mk)
11import Data.Either (isRight)
11import Data.Either (isRight)
12import Data.List.Split (wordsBy)
12import Data.List.Split (wordsBy)
13−import Data.Maybe (isJust)
13+import Data.Maybe (fromMaybe, isJust)
14−import Data.Monoid ((<>))
14+import Data.Semigroup (Semigroup (..))
15−import Data.Text (Text)
15+import qualified Data.Text as T
16+import Data.Time (UTCTime, defaultTimeLocale, parseTimeM,
16import GHC.Generics (Generic)
18import GHC.Generics (Generic)
17import Network.HTTP.Client (Manager, Request, Response, httpLbs,
19import Network.HTTP.Client (Manager, Request, Response, httpLbs,
20+ method, parseRequest, requestHeaders,
18− method, responseBody, responseHeaders,
21+ responseBody, responseHeaders,
19 responseStatus)
22 responseStatus)
23+import Network.HTTP.Media (matchAccept)
20import Network.HTTP.Types (methodGet, methodHead, parseMethod,
24import Network.HTTP.Types (methodGet, methodHead, parseMethod,
25+ renderStdMethod, status100, status200,
26+ status201, status300, status401,
21− status401, renderStdMethod, status405, status500)
27+ status405, status500)
29+import System.Clock (Clock (Monotonic), diffTimeSpec,
32+import Servant.QuickCheck.Internal.ErrorTypes
23-- | [__Best Practice__]
35-- | [__Best Practice__]
@@ -27,8 +39,27 @@ import Network.HTTP.Types (methodGet, methodHead, parseMethod,
27-- indication of how to proceed or what went wrong.
39-- indication of how to proceed or what went wrong.
29-- This function checks that the response code is not 500.
41-- This function checks that the response code is not 500.
30−not500 :: ResponsePredicate Text Bool
44+not500 :: ResponsePredicate
31−not500 = ResponsePredicate "not500" (\resp -> not $ responseStatus resp == status500)
45+not500 = ResponsePredicate $ \resp ->
46+ when (responseStatus resp == status500) $ throw $ PredicateFailure "not500" Nothing resp
50+-- This function checks that the response from the server does not take longer
51+-- than the specified number of nanoseconds.
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
33-- | [__Best Practice__]
64-- | [__Best Practice__]
@@ -49,11 +80,17 @@ not500 = ResponsePredicate "not500" (\resp -> not $ responseStatus resp == statu
50-- * JSON Grammar: <https://tools.ietf.org/html/rfc7159#section-2 RFC 7159 Section 2>
81-- * JSON Grammar: <https://tools.ietf.org/html/rfc7159#section-2 RFC 7159 Section 2>
51-- * JSON Grammar: <https://tools.ietf.org/html/rfc4627#section-2 RFC 4627 Section 2>
82-- * JSON Grammar: <https://tools.ietf.org/html/rfc4627#section-2 RFC 4627 Section 2>
52−onlyJsonObjects :: ResponsePredicate Text Bool
85+onlyJsonObjects :: ResponsePredicate
53onlyJsonObjects
86onlyJsonObjects
87+ = ResponsePredicate (\resp -> do
88+ case lookup "content-type" (first foldedCase <$> responseHeaders resp) of
90+ Just ctype -> when ("application/json" `SBS.isPrefixOf` ctype) $ do
54− = ResponsePredicate "onlyJsonObjects" (\resp -> case decode (responseBody resp) of
91+ case (decode (responseBody resp) :: Maybe Object) of
55− Nothing -> False
92+ Nothing -> throw $ PredicateFailure "onlyJsonObjects" Nothing resp
56− Just (_ :: Object) -> True)
93+ Just _ -> return ())
58-- | __Optional__
95-- | __Optional__
@@ -72,23 +109,61 @@ onlyJsonObjects
73-- * 201 Created: <https://tools.ietf.org/html/rfc7231#section-6.3.2 RFC 7231 Section 6.3.2>
110-- * 201 Created: <https://tools.ietf.org/html/rfc7231#section-6.3.2 RFC 7231 Section 6.3.2>
74-- * Location header: <https://tools.ietf.org/html/rfc7231#section-7.1.2 RFC 7231 Section 7.1.2>
111-- * Location header: <https://tools.ietf.org/html/rfc7231#section-7.1.2 RFC 7231 Section 7.1.2>
75−{-createContainsValidLocation :: RequestPredicate Text Bool-}
114+createContainsValidLocation :: RequestPredicate
76−{-createContainsValidLocation-}
115+createContainsValidLocation
77− {-= RequestPredicate-}
116+ = RequestPredicate $ \req mgr -> do
78− {-{ reqPredName = "createContainsValidLocation"-}
117+ let n = "createContainsValidLocation"
79− {-, reqResps = \req mg -> do-}
80− {-resp <- httpLbs mgr req-}
118+ resp <- httpLbs req mgr
81− {-if responseStatus resp == status201-}
119+ if responseStatus resp == status201
82− {-then case lookup "Location" $ responseHeaders resp of-}
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
125+ resp2 <- httpLbs x mgr
126+ status2XX (Just req) resp2 n
83− {-Nothing -> return []-}
127+ return [resp, resp2]
84− {-Just l -> if-}
128+ else return [resp]
86−{-
130+-- | [__Optional__]
132+-- The @Last-Modified@ header represents the time a resource was last
133+-- modified. It is used to drive caching and conditional requests.
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.
141+-- The @Last-Modified@ header can also be used in conjunction with the
142+-- @If-Unmodified-Since@ header to drive optimistic concurrency.
144+-- The @Last-Modified@ date must be in RFC 822 format.
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>
87−getsHaveLastModifiedHeader :: ResponsePredicate Text Bool
155+getsHaveLastModifiedHeader :: RequestPredicate
88getsHaveLastModifiedHeader
156getsHaveLastModifiedHeader
89− = ResponsePredicate "getsHaveLastModifiedHeader" (\resp ->
157+ = RequestPredicate $ \req mgr ->
158+ if (method req == methodGet)
160+ resp <- httpLbs req mgr
161+ unless (hasValidHeader "Last-Modified" isRFC822Date resp) $ do
162+ throw $ PredicateFailure "getsHaveLastModifiedHeader" (Just req) resp
93-- | [__RFC Compliance__]
168-- | [__RFC Compliance__]
@@ -100,51 +175,61 @@ getsHaveLastModifiedHeader
100-- This function checks that every @405 Method Not Allowed@ response contains
175-- This function checks that every @405 Method Not Allowed@ response contains
101-- an @Allow@ header with a list of standard HTTP methods.
176-- an @Allow@ header with a list of standard HTTP methods.
178+-- Note that 'servant' itself does not currently set the @Allow@ headers.
103-- __References__:
180-- __References__:
105-- * @Allow@ header: <https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html RFC 2616 Section 14.7>
182-- * @Allow@ header: <https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html RFC 2616 Section 14.7>
106-- * Status 405: <https://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html RFC 2616 Section 10.4.6>
183-- * 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>
107−notAllowedContainsAllowHeader :: RequestPredicate Text Bool
187+notAllowedContainsAllowHeader :: RequestPredicate
108notAllowedContainsAllowHeader
188notAllowedContainsAllowHeader
109− = RequestPredicate
189+ = RequestPredicate $ \req mgr -> do
110− { reqPredName = "notAllowedContainsAllowHeader"
111− , reqResps = \req mgr -> do
112− resp <- mapM (flip httpLbs mgr) $ [ req { method = renderStdMethod m }
190+ let reqs = [ req { method = renderStdMethod m } | m <- [minBound .. maxBound]
113− | m <- [minBound .. maxBound ]
114− , renderStdMethod m /= method req ]
191+ , renderStdMethod m /= method req ]
115− return (all pred' resp, resp)
192+ resp <- mapM (flip httpLbs mgr) reqs
194+ case filter pred' (zip reqs resp) of
195+ (x:_) -> throw $ PredicateFailure "notAllowedContainsAllowHeader" (Just $ fst x) (snd x)
118− pred' resp = responseStatus resp /= status405 || hasValidHeader "Allow" go resp
198+ pred' (_, resp) = responseStatus resp == status405 && not (hasValidHeader "Allow" go resp)
120 go x = all (\y -> isRight $ parseMethod $ SBSC.pack y)
200 go x = all (\y -> isRight $ parseMethod $ SBSC.pack y)
121 $ wordsBy (`elem` (", " :: [Char])) (SBSC.unpack x)
201 $ wordsBy (`elem` (", " :: [Char])) (SBSC.unpack x)
204+-- | [__RFC Compliance__]
124−-- | When a request contains an @Accept@ header, the server must either return
206+-- When a request contains an @Accept@ header, the server must either return
125-- content in one of the requested representations, or respond with @406 Not
207-- content in one of the requested representations, or respond with @406 Not
126-- Acceptable@.
208-- Acceptable@.
128-- This function checks that every *successful* response has a @Content-Type@
210-- This function checks that every *successful* response has a @Content-Type@
129−-- header that matches the @Accept@ header.
211+-- header that matches the @Accept@ header. It does *not* check that the server
212+-- matches the quality descriptions of the @Accept@ header correctly.
131-- __References__:
214-- __References__:
133-- * @Accept@ header: <https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html RFC 2616 Section 14.1>
216-- * @Accept@ header: <https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html RFC 2616 Section 14.1>
134−honoursAcceptHeader :: RequestPredicate b Bool
219+honoursAcceptHeader :: RequestPredicate
135honoursAcceptHeader
220honoursAcceptHeader
136− = RequestPredicate name (ResponsePredicate name $ \req mgr -> do
221+ = RequestPredicate $ \req mgr -> do
138 resp <- httpLbs req mgr
222 resp <- httpLbs req mgr
139 let scode = responseStatus resp
223 let scode = responseStatus resp
140− sctype = maybeToList $ lookup "Content-Type" $ responseHeaders resp
224+ sctype = lookup "Content-Type" $ responseHeaders resp
141− sacc = fromMaybe "*/*" $ lookup "Accept" $ requestHeaders req
225+ sacc = fromMaybe "*/*" $ lookup "Accept" (requestHeaders req)
142− if 100 < scode && scode < 300
226+ if status100 < scode && scode < status300
143− then isJust matchAccept sacc sctype
227+ then if isJust $ sctype >>= \x -> matchAccept [x] sacc
145− where name = "honoursAcceptHeader"
228+ then throw $ PredicateFailure "honoursAcceptHeader" (Just req) resp
148-- | [__Best Practice__]
233-- | [__Best Practice__]
150-- Whether or not a representation should be cached, it is good practice to
235-- Whether or not a representation should be cached, it is good practice to
@@ -157,32 +242,34 @@ honoursAcceptHeader
157-- __References__:
242-- __References__:
159-- * @Cache-Control@ header: <https://tools.ietf.org/html/rfc7234#section-5.2 RFC 7234 Section 5.2>
244-- * @Cache-Control@ header: <https://tools.ietf.org/html/rfc7234#section-5.2 RFC 7234 Section 5.2>
160−getsHaveCacheControlHeader :: RequestPredicate Text Bool
247+getsHaveCacheControlHeader :: RequestPredicate
161getsHaveCacheControlHeader
248getsHaveCacheControlHeader
162− = RequestPredicate
249+ = RequestPredicate $ \req mgr ->
163− { reqPredName = "getsHaveCacheControlHeader"
164− , reqResps = \req mgr -> if method req == methodGet
250+ if (method req == methodGet)
166− resp <- httpLbs req mgr
252+ resp <- httpLbs req mgr
167− let good = isJust $ lookup "Cache-Control" $ responseHeaders resp
253+ unless (hasValidHeader "Cache-Control" (const True) resp) $ do
168− return (good, [resp])
254+ throw $ PredicateFailure "getsHaveCacheControlHeader" (Just req) resp
169− else return (True, [])
255+ return [resp]
170− }
256+ else return []
172-- | [__Best Practice__]
258-- | [__Best Practice__]
174-- Like 'getsHaveCacheControlHeader', but for @HEAD@ requests.
260-- Like 'getsHaveCacheControlHeader', but for @HEAD@ requests.
175−headsHaveCacheControlHeader :: RequestPredicate Text Bool
263+headsHaveCacheControlHeader :: RequestPredicate
176headsHaveCacheControlHeader
264headsHaveCacheControlHeader
177− = RequestPredicate
265+ = RequestPredicate $ \req mgr ->
178− { reqPredName = "headsHaveCacheControlHeader"
179− , reqResps = \req mgr -> if method req == methodHead
266+ if (method req == methodHead)
181− resp <- httpLbs req mgr
268+ resp <- httpLbs req mgr
182− let good = isJust $ lookup "Cache-Control" $ responseHeaders resp
269+ unless (hasValidHeader "Cache-Control" (const True) resp) $
183− return (good, [resp])
270+ throw $ PredicateFailure "headsHaveCacheControlHeader" (Just req) resp
184− else return (True, [])
272+ else return []
@@ -242,12 +329,37 @@ linkHeadersAreValid
242-- __References__:
329-- __References__:
244-- * @WWW-Authenticate@ header: <https://tools.ietf.org/html/rfc7235#section-4.1 RFC 7235 Section 4.1>
331-- * @WWW-Authenticate@ header: <https://tools.ietf.org/html/rfc7235#section-4.1 RFC 7235 Section 4.1>
245−unauthorizedContainsWWWAuthenticate :: ResponsePredicate Text Bool
334+unauthorizedContainsWWWAuthenticate :: ResponsePredicate
246unauthorizedContainsWWWAuthenticate
335unauthorizedContainsWWWAuthenticate
247− = ResponsePredicate "unauthorizedContainsWWWAuthenticate" (\resp ->
336+ = ResponsePredicate $ \resp ->
248 if responseStatus resp == status401
337 if responseStatus resp == status401
249− then hasValidHeader "WWW-Authenticate" (const True) resp
338+ then unless (hasValidHeader "WWW-Authenticate" (const True) resp) $
339+ throw $ PredicateFailure "unauthorizedContainsWWWAuthenticate" Nothing resp
343+-- | [__RFC Compliance__]
345+-- [An HTML] document will start with exactly this string: <!DOCTYPE html>
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`.
352+-- * HTML5 Doctype: <https://tools.ietf.org/html/rfc7992#section-6.1 RFC 7992 Section 6.1>
354+htmlIncludesDoctype :: ResponsePredicate
356+ = ResponsePredicate $ \resp ->
357+ if hasValidHeader "Content-Type" (SBS.isPrefixOf . foldCase $ "text/html") resp
359+ let htmlContent = foldCase . LBS.take 20 $ responseBody resp
360+ unless (LBS.isPrefixOf (foldCase "<!doctype html>") htmlContent) $
361+ throw $ PredicateFailure "htmlIncludesDoctype" Nothing resp
250− else True)
362+ else return ()
252-- * Predicate logic
364-- * Predicate logic
@@ -257,76 +369,77 @@ unauthorizedContainsWWWAuthenticate
258-- Still, this is all kind of ugly.
370-- Still, this is all kind of ugly.
372+-- | A predicate that depends only on the response.
260−data ResponsePredicate n r = ResponsePredicate
375+newtype ResponsePredicate = ResponsePredicate
262− , respPred :: Response LBS.ByteString -> r
376+ { getResponsePredicate :: Response LBS.ByteString -> IO ()
263− } deriving (Functor, Generic)
377+ } deriving (Generic)
265−instance Bifunctor ResponsePredicate where
379+instance Semigroup ResponsePredicate where
266− first f (ResponsePredicate a b) = ResponsePredicate (f a) b
380+ ResponsePredicate a <> ResponsePredicate b = ResponsePredicate $ \x -> a x >> b x
269−instance (Monoid n, Monoid r) => Monoid (ResponsePredicate n r) where
382+instance Monoid ResponsePredicate where
270− mempty = ResponsePredicate mempty mempty
383+ mempty = ResponsePredicate $ const $ return ()
271− a `mappend` b = ResponsePredicate
384+ mappend = (<>)
272− { respPredName = respPredName a <> respPredName b
273− , respPred = respPred a <> respPred b
386+-- | A predicate that depends on both the request and the response.
276−data RequestPredicate n r = RequestPredicate
389+newtype RequestPredicate = RequestPredicate
278− , reqResps :: Request -> Manager -> IO (r, [Response LBS.ByteString])
390+ { getRequestPredicate :: Request -> Manager -> IO [Response LBS.ByteString]
279− } deriving (Generic, Functor)
391+ } deriving (Generic)
393+-- TODO: This isn't actually a monoid
281−instance Bifunctor RequestPredicate where
394+instance Monoid RequestPredicate where
282− first f (RequestPredicate a b) = RequestPredicate (f a) b
395+ mempty = RequestPredicate (\r m -> httpLbs r m >>= \x -> return ([x]))
283− second = fmap
396+ mappend = (<>)
285-- TODO: This isn't actually a monoid
398-- TODO: This isn't actually a monoid
286−instance (Monoid n, Monoid r) => Monoid (RequestPredicate n r) where
399+instance Semigroup RequestPredicate where
287− mempty = RequestPredicate mempty (\r m -> httpLbs r m >>= \x -> return (mempty, [x]))
288− a `mappend` b = RequestPredicate
400+ RequestPredicate a <> RequestPredicate b = RequestPredicate $ \r mgr ->
289− { reqPredName = reqPredName a <> reqPredName b
401+ liftM2 (<>) (a r mgr) (b r mgr)
290− , reqResps = \x m -> liftM2 (<>) (reqResps a x m) (reqResps b x m)
293−data Predicates n r = Predicates
294− { reqPreds :: RequestPredicate n r
295− , respPreds :: ResponsePredicate n r
296− } deriving (Generic, Functor)
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)
403+-- | A set of predicates. Construct one with 'mempty' and '<%>'.
404+data Predicates = Predicates
405+ { requestPredicates :: RequestPredicate
406+ , responsePredicates :: ResponsePredicate
407+ } deriving (Generic)
409+instance Semigroup Predicates where
410+ a <> b = Predicates (requestPredicates a <> requestPredicates b)
411+ (responsePredicates a <> responsePredicates b)
304−class JoinPreds a where
413+instance Monoid Predicates where
305− joinPreds :: a -> Predicates [Text] [Text] -> Predicates [Text] [Text]
414+ mempty = Predicates mempty mempty
307−instance JoinPreds (RequestPredicate Text Bool) where
417+class JoinPreds a where
308− joinPreds p (Predicates x y) = Predicates (go <> x) y
418+ joinPreds :: a -> Predicates -> Predicates
309− where go = let p' = first return p
310− in fmap (\z -> if z then [] else reqPredName p') p'
312−instance JoinPreds (ResponsePredicate Text Bool) where
420+instance JoinPreds (RequestPredicate ) where
313− joinPreds p (Predicates x y) = Predicates x (go <> y)
421+ joinPreds p (Predicates x y) = Predicates (p <> x) y
314− where go = let p' = first return p
315− in fmap (\z -> if z then [] else respPredName p') p'
423+instance JoinPreds (ResponsePredicate ) where
424+ joinPreds p (Predicates x y) = Predicates x (p <> y)
318-- | Adds a new predicate (either `ResponsePredicate` or `RequestPredicate`) to
426-- | Adds a new predicate (either `ResponsePredicate` or `RequestPredicate`) to
319-- the existing predicates.
427-- the existing predicates.
321-- > not500 <%> onlyJsonObjects <%> empty
429-- > not500 <%> onlyJsonObjects <%> empty
322−(<%>) :: JoinPreds a => a -> Predicates [Text] [Text] -> Predicates [Text] [Text]
432+(<%>) :: JoinPreds a => a -> Predicates -> Predicates
323(<%>) = joinPreds
433(<%>) = joinPreds
324infixr 6 <%>
434infixr 6 <%>
326−finishPredicates :: Predicates [Text] [Text] -> Request -> Manager -> IO [Text]
436+finishPredicates :: Predicates -> Request -> Manager -> IO (Maybe PredicateFailure)
327−finishPredicates p req mgr = do
437+finishPredicates p req mgr = go `catch` \(e :: PredicateFailure) -> return $ Just e
328− (soFar, resps) <- reqResps (reqPreds p) req mgr
438+ where
329− return $ soFar <> mconcat [respPred (respPreds p) r | r <- resps]
439+ go = do
440+ resps <- getRequestPredicate (requestPredicates p) req mgr
441+ mapM_ (getResponsePredicate $ responsePredicates p) resps
331-- * helpers
444-- * helpers
@@ -334,3 +447,15 @@ hasValidHeader :: SBS.ByteString -> (SBS.ByteString -> Bool) -> Response b -> Bo
334hasValidHeader hdr p r = case lookup (mk hdr) (responseHeaders r) of
447hasValidHeader hdr p r = case lookup (mk hdr) (responseHeaders r) of
335 Nothing -> False
448 Nothing -> False
336 Just v -> p v
449 Just v -> p v
451+isRFC822Date :: SBS.ByteString -> Bool
453+ = case parseTimeM True defaultTimeLocale rfc822DateFormat (SBSC.unpack s) of
455+ Just (_ :: UTCTime) -> True
457+status2XX :: Monad m => Maybe Request -> Response LBS.ByteString -> T.Text -> m ()
458+status2XX mreq resp t
459+ | status200 <= responseStatus resp && responseStatus resp < status300
461+ | otherwise = throw $ PredicateFailure t mreq resp