servant/servant-server/test/Servant/Server/RouterSpec.hs
Andres Loeh b1a6d88845 Revise the Router type to allow proper sharing.
We've previously used functions in the Router type to provide
information for subrouters. But this accesses the Requests too
early, and breaks sharing of the router structure in general,
causing the Router or large parts of the Router to be recomputed
on every request.

We now do not use functions anymore, and properly compute all
static parts of the router first, and gain access to the request
only in Delayed.

This also turns the code used within Delayed into a proper monad
now called DelayedIO, making some of the code using it a bit
nicer.
2016-04-12 09:38:49 +02:00

293 lines
8.7 KiB
Haskell

{-# LANGUAGE DataKinds #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE TypeOperators #-}
module Servant.Server.RouterSpec (spec) where
import Control.Monad (unless)
import Data.Proxy (Proxy(..))
import Data.Text (unpack)
import Network.HTTP.Types (Status (..))
import Network.Wai (Application, responseBuilder)
import Network.Wai.Internal (Response (ResponseBuilder))
import Test.Hspec
import Test.Hspec.Wai (get, shouldRespondWith, with)
import Servant.API
import Servant.Server
import Servant.Server.Internal
spec = describe "Servant.Server.Internal.Router" $ do
routerSpec
distributivitySpec
routerSpec :: Spec
routerSpec = do
let app' :: Application
app' = toApplication $ runRouter router'
router', router :: Router ()
router' = tweakResponse (fmap twk) router
router = leafRouter $ \_ _ cont -> cont (Route $ responseBuilder (Status 201 "") [] "")
twk :: Response -> Response
twk (ResponseBuilder (Status i s) hs b) = ResponseBuilder (Status (i + 1) s) hs b
twk b = b
describe "tweakResponse" . with (return app') $ do
it "calls f on route result" $ do
get "" `shouldRespondWith` 202
distributivitySpec :: Spec
distributivitySpec =
describe "choice" $ do
it "distributes endpoints through static paths" $ do
endpoint `shouldHaveSameStructureAs` endpointRef
it "distributes nested routes through static paths" $ do
static `shouldHaveSameStructureAs` staticRef
it "distributes nested routes through dynamic paths" $ do
dynamic `shouldHaveSameStructureAs` dynamicRef
it "properly reorders permuted static paths" $ do
permute `shouldHaveSameStructureAs` permuteRef
it "properly reorders permuted static paths in the presence of Raw in end" $ do
permuteRawEnd `shouldHaveSameStructureAs` permuteRawEndRef
it "properly reorders permuted static paths in the presence of Raw in beginning" $ do
permuteRawBegin `shouldHaveSameStructureAs` permuteRawBeginRef
it "properly reorders permuted static paths in the presence of Raw in middle" $ do
permuteRawMiddle `shouldHaveSameStructureAs` permuteRawMiddleRef
it "properly reorders permuted static paths in the presence of a root endpoint in end" $ do
permuteEndEnd `shouldHaveSameStructureAs` permuteEndRef
it "properly reorders permuted static paths in the presence of a root endpoint in beginning" $ do
permuteEndBegin `shouldHaveSameStructureAs` permuteEndRef
it "properly reorders permuted static paths in the presence of a root endpoint in middle" $ do
permuteEndMiddle `shouldHaveSameStructureAs` permuteEndRef
it "properly handles mixing static paths at different levels" $ do
level `shouldHaveSameStructureAs` levelRef
shouldHaveSameStructureAs ::
(HasServer api1 '[], HasServer api2 '[]) => Proxy api1 -> Proxy api2 -> Expectation
shouldHaveSameStructureAs p1 p2 =
unless (sameStructure (makeTrivialRouter p1) (makeTrivialRouter p2)) $
expectationFailure ("expected:\n" ++ unpack (layout p2) ++ "\nbut got:\n" ++ unpack (layout p1))
makeTrivialRouter :: (HasServer layout '[]) => Proxy layout -> Router ()
makeTrivialRouter p =
route p EmptyContext (emptyDelayed (FailFatal err501))
type End = Get '[JSON] ()
-- The latter version looks more efficient,
-- but the former should be compiled to the
-- same layout:
type Endpoint = "a" :> End :<|> "a" :> End
type EndpointRef = "a" :> (End :<|> End)
endpoint :: Proxy Endpoint
endpoint = Proxy
endpointRef :: Proxy EndpointRef
endpointRef = Proxy
-- Again, the latter version looks more efficient,
-- but the former should be compiled to the same
-- layout:
type Static = "a" :> "b" :> End :<|> "a" :> "c" :> End
type StaticRef = "a" :> ("b" :> End :<|> "c" :> End)
static :: Proxy Static
static = Proxy
staticRef :: Proxy StaticRef
staticRef = Proxy
-- Even for dynamic path components, we expect the
-- router to simplify the layout, because captures
-- are delayed and only actually performed once
-- reaching an endpoint. So the former version and
-- the latter should be compiled to the same router
-- structure:
type Dynamic =
"a" :> Capture "foo" Int :> "b" :> End
:<|> "a" :> Capture "bar" Bool :> "c" :> End
:<|> "a" :> Capture "baz" Char :> "d" :> End
type DynamicRef =
"a" :> Capture "anything" () :>
("b" :> End :<|> "c" :> End :<|> "d" :> End)
dynamic :: Proxy Dynamic
dynamic = Proxy
dynamicRef :: Proxy DynamicRef
dynamicRef = Proxy
-- A more complicated example of static route reordering.
-- All the permuted paths should be correctly grouped,
-- so both 'Permute' and 'PermuteRef' should compile to
-- the same layout:
type Permute =
"a" :> "b" :> "c" :> End
:<|> "b" :> "a" :> "c" :> End
:<|> "a" :> "c" :> "b" :> End
:<|> "c" :> "a" :> "b" :> End
:<|> "b" :> "c" :> "a" :> End
:<|> "c" :> "b" :> "a" :> End
type PermuteRef =
"a" :> ( "b" :> "c" :> End
:<|> "c" :> "b" :> End
)
:<|> "b" :> ( "a" :> "c" :> End
:<|> "c" :> "a" :> End
)
:<|> "c" :> ( "a" :> "b" :> End
:<|> "b" :> "a" :> End
)
permute :: Proxy Permute
permute = Proxy
permuteRef :: Proxy PermuteRef
permuteRef = Proxy
-- Adding a 'Raw' in one of the ends should have minimal
-- effect on the grouping.
type PermuteRawEnd =
"a" :> "b" :> "c" :> End
:<|> "b" :> "a" :> "c" :> End
:<|> "a" :> "c" :> "b" :> End
:<|> "c" :> "a" :> "b" :> End
:<|> "b" :> "c" :> "a" :> End
:<|> "c" :> "b" :> "a" :> End
:<|> Raw
type PermuteRawEndRef = PermuteRef :<|> Raw
type PermuteRawBegin =
Raw
:<|> "a" :> "b" :> "c" :> End
:<|> "b" :> "a" :> "c" :> End
:<|> "a" :> "c" :> "b" :> End
:<|> "c" :> "a" :> "b" :> End
:<|> "b" :> "c" :> "a" :> End
:<|> "c" :> "b" :> "a" :> End
type PermuteRawBeginRef = Raw :<|> PermuteRef
permuteRawBegin :: Proxy PermuteRawBegin
permuteRawBegin = Proxy
permuteRawBeginRef :: Proxy PermuteRawBeginRef
permuteRawBeginRef = Proxy
permuteRawEnd :: Proxy PermuteRawEnd
permuteRawEnd = Proxy
permuteRawEndRef :: Proxy PermuteRawEndRef
permuteRawEndRef = Proxy
-- Adding a 'Raw' in the middle will disrupt grouping,
-- because we commute things past a 'Raw'. But the two
-- halves should still be grouped.
type PermuteRawMiddle =
"a" :> "b" :> "c" :> End
:<|> "b" :> "a" :> "c" :> End
:<|> "a" :> "c" :> "b" :> End
:<|> Raw
:<|> "c" :> "a" :> "b" :> End
:<|> "b" :> "c" :> "a" :> End
:<|> "c" :> "b" :> "a" :> End
type PermuteRawMiddleRef =
"a" :> ( "b" :> "c" :> End
:<|> "c" :> "b" :> End
)
:<|> "b" :> "a" :> "c" :> End
:<|> Raw
:<|> "b" :> "c" :> "a" :> End
:<|> "c" :> ( "a" :> "b" :> End
:<|> "b" :> "a" :> End
)
permuteRawMiddle :: Proxy PermuteRawMiddle
permuteRawMiddle = Proxy
permuteRawMiddleRef :: Proxy PermuteRawMiddleRef
permuteRawMiddleRef = Proxy
-- Adding an endpoint at the top-level in various places
-- is also somewhat critical for grouping, but it should
-- not disrupt grouping at all, even if it is placed in
-- the middle.
type PermuteEndEnd =
"a" :> "b" :> "c" :> End
:<|> "b" :> "a" :> "c" :> End
:<|> "a" :> "c" :> "b" :> End
:<|> "c" :> "a" :> "b" :> End
:<|> "b" :> "c" :> "a" :> End
:<|> "c" :> "b" :> "a" :> End
:<|> End
type PermuteEndBegin =
End
:<|> "a" :> "b" :> "c" :> End
:<|> "b" :> "a" :> "c" :> End
:<|> "a" :> "c" :> "b" :> End
:<|> "c" :> "a" :> "b" :> End
:<|> "b" :> "c" :> "a" :> End
:<|> "c" :> "b" :> "a" :> End
type PermuteEndMiddle =
"a" :> "b" :> "c" :> End
:<|> "b" :> "a" :> "c" :> End
:<|> "a" :> "c" :> "b" :> End
:<|> End
:<|> "c" :> "a" :> "b" :> End
:<|> "b" :> "c" :> "a" :> End
:<|> "c" :> "b" :> "a" :> End
type PermuteEndRef = PermuteRef :<|> End
permuteEndEnd :: Proxy PermuteEndEnd
permuteEndEnd = Proxy
permuteEndBegin :: Proxy PermuteEndBegin
permuteEndBegin = Proxy
permuteEndMiddle :: Proxy PermuteEndMiddle
permuteEndMiddle = Proxy
permuteEndRef :: Proxy PermuteEndRef
permuteEndRef = Proxy
-- An API with routes on different nesting levels that
-- is composed out of different fragments should still
-- be reordered correctly.
type LevelFragment1 =
"a" :> "b" :> End
:<|> "a" :> End
type LevelFragment2 =
"b" :> End
:<|> "a" :> "c" :> End
:<|> End
type Level = LevelFragment1 :<|> LevelFragment2
type LevelRef =
"a" :> ("b" :> End :<|> "c" :> End :<|> End)
:<|> "b" :> End
:<|> End
level :: Proxy Level
level = Proxy
levelRef :: Proxy LevelRef
levelRef = Proxy