@@ -10,62 +10,22 @@ import Control.Monad.IO.Class
1010import Data.ByteString (ByteString)
1111import Data.Kind
1212import Data.Proxy
13−import qualified Data.Sequence as Seq
14−import qualified Network.Wai as Wai
13+import Network.Wai
1514import Servant.API
16−import Servant.Client.Core
1715import Servant.Server
1816import Servant.Server.Internal
1917
20−-- | Combinator for your Servant API description. Prepend it to your API for greater enjoyment!
21−-- Example:
22−--
23−-- @
24−-- type MyAPI = RequestTracking :> "ping" :> Get '[JSON] Text
25−-- @
26−--
27−-- In addition to the API combinator, you also need to create a context handler that will
28−-- handler the tracking data (see 'ReqtrackInfo') and produce desired output, which in turn
29−-- will be passed to your API handlers.
30−-- The type of values passed to API handlers is controlled by @type instance TrackingData RequestTracking@,
31−-- which isn't set by default.
32−-- The server code should look something like this:
33−--
34−-- @
35−-- data TrackingArg = ...
36−--
37−-- type instance TrackingData RequestTracking = TrackingArg
38−--
39−-- trackingHandler :: ReqtrackingHandler (Maybe ReqtrackInfo) TrackingArg
40−-- trackingHandler = mkReqtrackingHandler $ \mrti ->
41−-- case mrti of
42−-- Just rti -> ... -- Do something with ReqtrackInfo, return TrackingArg
43−-- Nothing -> ...
44−--
45−-- @
18+-- | Types to use in you API description
4619data RequestTracking
4720
48−-- | See 'RequestTracking'
49−type family TrackingData a
21+type family TrackingData :: Type -> Type
5022
5123-- | Same as above, except no argument is passed to a handler.
5224data RequestTracking_
5325
54−-- | Servant context handler used for processing 'ReqtrackInfo' before passing the result to endpoint handlers.
55−-- Use 'mkReqtrackingHandler' in your code instead of the constructor.
56−newtype ReqtrackingHandler r o = ReqtrackingHandler { runReqtrackingHandler :: r -> Handler o
26+newtype ReqtrackingHandler r o = ReqtrackingHandler { unReqtrackingHandler :: r -> Handler o
5727 } deriving (Functor)
5828
59−instance Applicative (ReqtrackingHandler r) where
60− pure x = ReqtrackingHandler $ \_ -> pure x
61− f <*> v = ReqtrackingHandler $ \r -> runReqtrackingHandler f r <*> runReqtrackingHandler v r
62−
63−instance Monad (ReqtrackingHandler r) where
64− return = pure
65− f >>= g = ReqtrackingHandler $ \r -> do a <- runReqtrackingHandler f r
66− runReqtrackingHandler (g a) r
67−
68−-- | Smart constructor to create 'ReqtrackingHandler'.
6929mkReqtrackingHandler :: (Maybe ReqtrackInfo -> Handler o) -> ReqtrackingHandler (Maybe ReqtrackInfo) o
7030mkReqtrackingHandler = ReqtrackingHandler
7131
@@ -78,22 +38,12 @@ instance forall (api :: Type) context.
7838 hoistServerWithContext _ pc nt s = hoistServerWithContext (Proxy :: Proxy api) pc nt . s
7939
8040 route _ context subserver = route (Proxy :: Proxy api) context (subserver `addHeaderCheck` withRequest trackingCheck)
81− where trackingCheck :: Wai.Request -> DelayedIO (TrackingData RequestTracking)
41+ where trackingCheck :: Request -> DelayedIO (TrackingData RequestTracking)
8242 trackingCheck = either delayedFailFatal return <=< liftIO . runHandler . trackingHandler
83− trackingHandler :: Wai.Request -> Handler (TrackingData RequestTracking)
43+ trackingHandler :: Request -> Handler (TrackingData RequestTracking)
8444 trackingHandler = let ReqtrackingHandler h = getContextEntry context
8545 in h . parseTrackingHeaders
8646
87−instance HasClient m api => HasClient m (RequestTracking :> api) where
88− type Client m (RequestTracking :> api) = Maybe ReqtrackInfo -> Client m api
89−
90− clientWithRoute pm Proxy req mrti = clientWithRoute pm (Proxy :: Proxy api) req'
91− where req' | Just rti <- mrti = req { requestHeaders = Seq.fromList (mkTrackingHeaders rti) <> requestHeaders req }
92− | otherwise = req
93−
94− hoistClientMonad pm Proxy f cl = \rti -> hoistClientMonad pm (Proxy :: Proxy api) f (cl rti)
95−
96−
9747instance forall (api :: Type) context.
9848 ( HasServer api context
9949 , HasContextEntry context (ReqtrackingHandler (Maybe ReqtrackInfo) ())
@@ -103,20 +53,13 @@ instance forall (api :: Type) context.
10353 hoistServerWithContext _ pc nt s = hoistServerWithContext (Proxy :: Proxy api) pc nt s
10454
10555 route _ context subserver = route (Proxy :: Proxy api) context (fmap const subserver `addHeaderCheck` withRequest trackingCheck)
106− where trackingCheck :: Wai.Request -> DelayedIO ()
56+ where trackingCheck :: Request -> DelayedIO ()
10757 trackingCheck = either delayedFailFatal (const $ return ()) <=< liftIO . runHandler . trackingHandler
108− trackingHandler :: Wai.Request -> Handler ()
58+ trackingHandler :: Request -> Handler ()
10959 trackingHandler = let ReqtrackingHandler h = getContextEntry context
11060 in h . parseTrackingHeaders
11161
112−instance HasClient m api => HasClient m (RequestTracking_ :> api) where
113− type Client m (RequestTracking_ :> api) = Client m api
114−
115− clientWithRoute pm Proxy = clientWithRoute pm (Proxy :: Proxy api)
116− hoistClientMonad pm Proxy f cl = hoistClientMonad pm (Proxy :: Proxy api) f cl
117−
11862
119−-- | Headers list to use with 'Headers'. Currently unused.
12063type ReqtrackHeaders = '[ Header RequestIdHdr ByteString
12164 , Header RequestLevelHdr Word
12265 , Header RequestSourceHdr ByteString