urbit/pkg/hs/urbit-king/lib/Urbit/Vere/Eyre/KingSubsite.hs

113 lines
3.4 KiB
Haskell

{-|
KingSubsite: runtime-exclusive HTTP request handling, for /~_~
-}
module Urbit.Vere.Eyre.KingSubsite
( KingSubsite
, kingSubsite
, runKingSubsite
, fourOhFourSubsite
) where
import Urbit.Prelude hiding (Builder)
import Data.ByteString.Builder
import Urbit.King.Scry
import Urbit.Vere.Serf.Types
import Data.Conduit (ConduitT, Flush(..), yield)
import Data.Text.Encoding (encodeUtf8Builder)
import qualified Data.Text.Encoding as E
import qualified Network.HTTP.Types as H
import qualified Network.Wai as W
import qualified Network.Wai.Conduit as W
import qualified Urbit.Noun.Time as Time
newtype KingSubsite = KS { runKingSubsite :: W.Application }
data SlogAction
= KeepAlive
| Slog (Atom, Tank)
streamSlog :: Monad m => SlogAction -> ConduitT () (Flush Builder) m ()
streamSlog a = do
case a of
KeepAlive -> pure ()
Slog (_, t) -> for_ (wash (WashCfg 0 80) (tankTree t)) $ \l -> do
yield $ Chunk "data:"
yield $ Chunk $ encodeUtf8Builder $ unTape l
yield $ Chunk "\n"
yield $ Chunk "\n"
yield $ Flush
kingSubsite :: HasLogFunc e
=> Ship
-> (Time.Wen -> Gang -> Path -> IO (Maybe (Term, Noun)))
-> TVar ((Atom, Tank) -> IO ())
-> RAcquire e KingSubsite
kingSubsite who scry func = do
clients <- newTVarIO (mempty :: Map Word (SlogAction -> IO ()))
nextId <- newTVarIO (0 :: Word)
baton <- newTMVarIO ()
env <- ask
atomically $ writeTVar func $ \s -> readTVarIO clients >>= traverse_ ($ Slog s)
acquireWorker "Runtime subsite keep-alive" $ forever $ do
threadDelay 20_000_000
io $ readTVarIO clients >>= traverse_ ($ KeepAlive)
pure $ KS $ \req respond -> case W.pathInfo req of
["~_~", "slog"] -> bracket
(do
id <- atomically $ do
id <- readTVar nextId
modifyTVar' nextId (+ 1)
pure id
slogQ <- newTQueueIO
atomically $
modifyTVar' clients (insertMap id (atomically . writeTQueue slogQ))
pure (id, slogQ))
(\(id, _) -> atomically $ modifyTVar' clients (deleteMap id))
(\(_, q) -> do
authed <- authenticated env req
if not authed
then respond $ emptyResponse 403 "Permission Denied"
else
let loop = yield Flush
>> forever (atomically (readTQueue q) >>= streamSlog)
in respond $ W.responseSource (H.mkStatus 200 "OK") heads loop)
_ -> respond $ emptyResponse 404 "Not Found"
where
heads = [ ("Content-Type" , "text/event-stream")
, ("Cache-Control", "no-cache")
, ("Connection" , "keep-alive")
]
emptyResponse cod mes = W.responseLBS (H.mkStatus cod mes) [] ""
authenticated env req = runRIO env
$ (scryAuth $ getCookie req)
>>= pure . fromMaybe False
getCookie req = intercalate "; "
$ fmap (E.decodeUtf8 . snd)
$ filter ((== "cookie") . fst)
$ W.requestHeaders req
scryAuth :: HasLogFunc e
=> Text
-> RIO e (Maybe Bool)
scryAuth cookie =
scryNow scry "ex" who "" ["authenticated", "cookie", textAsTa cookie]
fourOhFourSubsite :: Ship -> KingSubsite
fourOhFourSubsite who = KS $ \req respond ->
respond $ W.responseLBS (H.mkStatus 404 "Not Found") [] body
where
body = toLazyByteString $ foldMap charUtf8 $ msg
msg = "Ship " <> show who <> " not docked."