graphql-engine/server/src-lib/Hasura/RQL/DDL/Headers.hs

57 lines
2.1 KiB
Haskell

module Hasura.RQL.DDL.Headers where
import Data.Aeson
import Hasura.Incremental (Cacheable)
import Hasura.Prelude
import Hasura.RQL.Instances ()
import Hasura.RQL.Types.Error
import Language.Haskell.TH.Syntax (Lift)
import System.Environment (lookupEnv)
import qualified Data.Text as T
data HeaderConf = HeaderConf HeaderName HeaderValue
deriving (Show, Eq, Lift, Generic)
instance NFData HeaderConf
instance Hashable HeaderConf
instance Cacheable HeaderConf
type HeaderName = T.Text
data HeaderValue = HVValue T.Text | HVEnv T.Text
deriving (Show, Eq, Lift, Generic)
instance NFData HeaderValue
instance Hashable HeaderValue
instance Cacheable HeaderValue
instance FromJSON HeaderConf where
parseJSON (Object o) = do
name <- o .: "name"
value <- o .:? "value"
valueFromEnv <- o .:? "value_from_env"
case (value, valueFromEnv ) of
(Nothing, Nothing) -> fail "expecting value or value_from_env keys"
(Just val, Nothing) -> return $ HeaderConf name (HVValue val)
(Nothing, Just val) -> return $ HeaderConf name (HVEnv val)
(Just _, Just _) -> fail "expecting only one of value or value_from_env keys"
parseJSON _ = fail "expecting object for headers"
instance ToJSON HeaderConf where
toJSON (HeaderConf name (HVValue val)) = object ["name" .= name, "value" .= val]
toJSON (HeaderConf name (HVEnv val)) = object ["name" .= name, "value_from_env" .= val]
-- | This is used by schema stitching
getHeadersFromConf :: (MonadError QErr m, MonadIO m) => [HeaderConf] -> m [(HeaderName, T.Text)]
getHeadersFromConf = mapM getHeader
where
getHeader :: (QErrM m, MonadIO m) => HeaderConf -> m (HeaderName, T.Text)
getHeader hconf = case hconf of
(HeaderConf name (HVValue val)) -> return (name, val)
(HeaderConf name (HVEnv val)) -> do
mEnv <- liftIO $ lookupEnv (T.unpack val)
case mEnv of
Nothing -> throw400 NotFound $ "environment variable '" <> val <> "' not set"
Just envval -> return (name, T.pack envval)