graphql-engine/server/src-lib/Hasura/Server/App.hs

{-# LANGUAGE CPP       #-}
{-# LANGUAGE DataKinds #-}

module Hasura.Server.App where

import           Control.Concurrent.MVar.Lifted
import           Control.Exception                      (IOException, try)
import           Control.Lens                           (view, _2)
import           Control.Monad.Stateless
import           Control.Monad.Trans.Control            (MonadBaseControl)
import           Data.Aeson                             hiding (json)
import           Data.Either                            (isRight)
import           Data.Int                               (Int64)
import           Data.IORef
import           Data.Time.Clock                        (UTCTime, getCurrentTime)
import           Data.Time.Clock.POSIX                  (getPOSIXTime)
import           Network.Mime                           (defaultMimeLookup)
import           System.Exit                            (exitFailure)
import           System.FilePath                        (joinPath, takeFileName)
import           Web.Spock.Core                         ((<//>))

import qualified Control.Concurrent.Async.Lifted.Safe   as LA
import qualified Data.ByteString.Lazy                   as BL
import qualified Data.CaseInsensitive                   as CI
import qualified Data.HashMap.Strict                    as M
import qualified Data.HashSet                           as S
import qualified Data.Text                              as T
import qualified Database.PG.Query                      as Q
import qualified Network.HTTP.Client                    as HTTP
import qualified Network.HTTP.Types                     as HTTP
import qualified Network.Wai                            as Wai
import qualified Network.Wai.Handler.WebSockets         as WS
import qualified Network.WebSockets                     as WS
import qualified System.Metrics                         as EKG
import qualified System.Metrics.Json                    as EKG
import qualified Text.Mustache                          as M
import qualified Web.Spock.Core                         as Spock

import           Hasura.EncJSON
import           Hasura.GraphQL.Resolve.Action
import           Hasura.HTTP
import           Hasura.Prelude                         hiding (get, put)
import           Hasura.RQL.DDL.Schema
import           Hasura.RQL.Types
import           Hasura.RQL.Types.Run
import           Hasura.Server.API.Config               (runGetConfig)
import           Hasura.Server.API.Query
import           Hasura.Server.Auth                     (AuthMode (..), UserAuthentication (..))
import           Hasura.Server.Compression
import           Hasura.Server.Cors
import           Hasura.Server.Init
import           Hasura.Server.Logging
import           Hasura.Server.Middleware               (corsMiddleware)
import           Hasura.Server.Migrate                  (migrateCatalog)
import           Hasura.Server.Utils
import           Hasura.Server.Version
import           Hasura.Session
import           Hasura.SQL.Types

import qualified Hasura.GraphQL.Execute                 as E
import qualified Hasura.GraphQL.Execute.LiveQuery       as EL
import qualified Hasura.GraphQL.Explain                 as GE
import qualified Hasura.GraphQL.Transport.HTTP          as GH
import qualified Hasura.GraphQL.Transport.HTTP.Protocol as GH
import qualified Hasura.GraphQL.Transport.WebSocket     as WS
import qualified Hasura.Logging                         as L
import qualified Hasura.Server.API.PGDump               as PGD


data SchemaCacheRef
  = SchemaCacheRef
  { _scrLock     :: MVar ()
  -- ^ The idea behind explicit locking here is to
  --
  --   1. Allow maximum throughput for serving requests (/v1/graphql) (as each
  --      request reads the current schemacache)
  --   2. We don't want to process more than one request at any point of time
  --      which would modify the schema cache as such queries are expensive.
  --
  -- Another option is to consider removing this lock in place of `_scrCache ::
  -- MVar ...` if it's okay or in fact correct to block during schema update in
  -- e.g.  _wseGCtxMap. Vamshi says: It is theoretically possible to have a
  -- situation (in between building new schemacache and before writing it to
  -- the IORef) where we serve a request with a stale schemacache but I guess
  -- it is an okay trade-off to pay for a higher throughput (I remember doing a
  -- bunch of benchmarks to test this hypothesis).
  , _scrCache    :: IORef (RebuildableSchemaCache Run, SchemaCacheVer)
  , _scrOnChange :: IO ()
  -- ^ an action to run when schemacache changes
  }

data ServerCtx
  = ServerCtx
  { scPGExecCtx                    :: !PGExecCtx
  , scConnInfo                     :: !Q.ConnInfo
  , scLogger                       :: !(L.Logger L.Hasura)
  , scCacheRef                     :: !SchemaCacheRef
  , scAuthMode                     :: !AuthMode
  , scManager                      :: !HTTP.Manager
  , scSQLGenCtx                    :: !SQLGenCtx
  , scEnabledAPIs                  :: !(S.HashSet API)
  , scInstanceId                   :: !InstanceId
  , scPlanCache                    :: !E.PlanCache
  , scLQState                      :: !EL.LiveQueriesState
  , scEnableAllowlist              :: !Bool
  , scEkgStore                     :: !EKG.Store
  , scResponseInternalErrorsConfig :: !ResponseInternalErrorsConfig
  }

data HandlerCtx
  = HandlerCtx
  { hcServerCtx  :: !ServerCtx
  , hcUser       :: !UserInfo
  , hcReqHeaders :: ![HTTP.Header]
  , hcRequestId  :: !RequestId
  }

type Handler m = ExceptT QErr (ReaderT HandlerCtx m)

data APIResp
  = JSONResp !(HttpResponse EncJSON)
  | RawResp  !(HttpResponse BL.ByteString)

data APIHandler m a
  = AHGet !(Handler m APIResp)
  | AHPost !(a -> Handler m APIResp)


boolToText :: Bool -> T.Text
boolToText = bool "false" "true"

isAdminSecretSet :: AuthMode -> T.Text
isAdminSecretSet AMNoAuth = boolToText False
isAdminSecretSet _        = boolToText True

getSCFromRef :: (MonadIO m) => SchemaCacheRef -> m SchemaCache
getSCFromRef scRef = lastBuiltSchemaCache . fst <$> liftIO (readIORef $ _scrCache scRef)

logInconsObjs :: L.Logger L.Hasura -> [InconsistentMetadata] -> IO ()
logInconsObjs logger objs =
  unless (null objs) $ L.unLogger logger $ mkInconsMetadataLog objs

withSCUpdate
  :: (MonadIO m, MonadBaseControl IO m)
  => SchemaCacheRef -> L.Logger L.Hasura -> m (a, RebuildableSchemaCache Run) -> m a
withSCUpdate scr logger action = do
  withMVarMasked lk $ \()-> do
    (!res, !newSC) <- action
    liftIO $ do
      -- update schemacache in IO reference
      modifyIORef' cacheRef $ \(_, prevVer) ->
        let !newVer = incSchemaCacheVer prevVer
          in (newSC, newVer)
      -- log any inconsistent objects
      logInconsObjs logger $ scInconsistentObjs $ lastBuiltSchemaCache newSC
      onChange
    return res
  where
    SchemaCacheRef lk cacheRef onChange = scr

mkGetHandler :: Handler m APIResp -> APIHandler m ()
mkGetHandler = AHGet

mkPostHandler :: (a -> Handler m APIResp) -> APIHandler m a
mkPostHandler = AHPost

mkAPIRespHandler :: (Functor m) => (a -> Handler m (HttpResponse EncJSON)) -> (a -> Handler m APIResp)
mkAPIRespHandler = (fmap . fmap) JSONResp

isMetadataEnabled :: ServerCtx -> Bool
isMetadataEnabled sc = S.member METADATA $ scEnabledAPIs sc

isGraphQLEnabled :: ServerCtx -> Bool
isGraphQLEnabled sc = S.member GRAPHQL $ scEnabledAPIs sc

isPGDumpEnabled :: ServerCtx -> Bool
isPGDumpEnabled sc = S.member PGDUMP $ scEnabledAPIs sc

isConfigEnabled :: ServerCtx -> Bool
isConfigEnabled sc = S.member CONFIG $ scEnabledAPIs sc

isDeveloperAPIEnabled :: ServerCtx -> Bool
isDeveloperAPIEnabled sc = S.member DEVELOPER $ scEnabledAPIs sc

-- {-# SCC parseBody #-}
parseBody :: (FromJSON a, MonadError QErr m) => BL.ByteString -> m a
parseBody reqBody =
  case eitherDecode' reqBody of
    Left e     -> throw400 InvalidJSON (T.pack e)
    Right jVal -> decodeValue jVal

onlyAdmin :: (Monad m) => Handler m ()
onlyAdmin = do
  uRole <- asks (_uiRole . hcUser)
  when (uRole /= adminRoleName) $
    throw400 AccessDenied "You have to be an admin to access this endpoint"

buildQCtx :: (MonadIO m) => Handler m QCtx
buildQCtx = do
  scRef    <- scCacheRef . hcServerCtx <$> ask
  userInfo <- asks hcUser
  cache <- getSCFromRef scRef
  sqlGenCtx <- scSQLGenCtx . hcServerCtx <$> ask
  return $ QCtx userInfo cache sqlGenCtx

setHeader :: MonadIO m => HTTP.Header -> Spock.ActionT m ()
setHeader (headerName, headerValue) =
  Spock.setHeader (bsToTxt $ CI.original headerName) (bsToTxt headerValue)

-- | Typeclass representing the metadata API authorization effect
class MetadataApiAuthorization m where
  authorizeMetadataApi :: RQLQuery -> UserInfo -> Handler m ()

mkSpockAction
  :: (HasVersion, MonadIO m, FromJSON a, ToJSON a, UserAuthentication m, HttpLog m)
  => ServerCtx
  -> (Bool -> QErr -> Value)
  -- ^ `QErr` JSON encoder function
  -> (QErr -> QErr)
  -- ^ `QErr` modifier
  -> APIHandler m a
  -> Spock.ActionT m ()
mkSpockAction serverCtx qErrEncoder qErrModifier apiHandler = do
    req <- Spock.request
    -- Bytes are actually read from the socket here. Time this.
    (ioWaitTime, reqBody) <- withElapsedTime $ liftIO $ Wai.strictRequestBody req
    let headers = Wai.requestHeaders req
        authMode = scAuthMode serverCtx
        manager = scManager serverCtx

    requestId <- getRequestId headers

    userInfoE <- fmap fst <$> lift (resolveUserInfo logger manager headers authMode)
    userInfo  <- either (logErrorAndResp Nothing requestId req (Left reqBody) False headers . qErrModifier)
                 return userInfoE

    let handlerState = HandlerCtx serverCtx userInfo headers requestId
        includeInternal = shouldIncludeInternal (_uiRole userInfo) $
                          scResponseInternalErrorsConfig serverCtx

    (serviceTime, (result, q)) <- withElapsedTime $ case apiHandler of
      AHGet handler -> do
        res <- lift $ runReaderT (runExceptT handler) handlerState
        return (res, Nothing)
      AHPost handler -> do
        parsedReqE <- runExceptT $ parseBody reqBody
        parsedReq  <- either (logErrorAndResp (Just userInfo) requestId req (Left reqBody) includeInternal headers . qErrModifier)
                      return parsedReqE
        res <- lift $ runReaderT (runExceptT $ handler parsedReq) handlerState
        return (res, Just parsedReq)

    -- apply the error modifier
    let modResult = fmapL qErrModifier result

    -- log and return result
    case modResult of
      Left err  -> let jErr = maybe (Left reqBody) (Right . toJSON) q
                   in logErrorAndResp (Just userInfo) requestId req jErr includeInternal headers err
      Right res -> logSuccessAndResp (Just userInfo) requestId req (fmap toJSON q) res (Just (ioWaitTime, serviceTime)) headers

    where
      logger = scLogger serverCtx

      logErrorAndResp
        :: (MonadIO m, HttpLog m)
        => Maybe UserInfo
        -> RequestId
        -> Wai.Request
        -> Either BL.ByteString Value
        -> Bool
        -> [HTTP.Header]
        -> QErr
        -> Spock.ActionCtxT ctx m a
      logErrorAndResp userInfo reqId req reqBody includeInternal headers qErr = do
        lift $ logHttpError logger userInfo reqId req reqBody qErr headers
        Spock.setStatus $ qeStatus qErr
        Spock.json $ qErrEncoder includeInternal qErr

      logSuccessAndResp userInfo reqId req reqBody result qTime reqHeaders =
        case result of
          JSONResp (HttpResponse encJson h) ->
            possiblyCompressedLazyBytes userInfo reqId req reqBody qTime (encJToLBS encJson)
              (pure jsonHeader <> h) reqHeaders
          RawResp (HttpResponse rawBytes h) ->
            possiblyCompressedLazyBytes userInfo reqId req reqBody qTime rawBytes h reqHeaders

      possiblyCompressedLazyBytes userInfo reqId req reqBody qTime respBytes respHeaders reqHeaders = do
        let (compressedResp, mEncodingHeader, mCompressionType) =
              compressResponse (Wai.requestHeaders req) respBytes
            encodingHeader = maybe [] pure mEncodingHeader
            reqIdHeader = (requestIdHeader, txtToBs $ unRequestId reqId)
            allRespHeaders = pure reqIdHeader <> encodingHeader <> respHeaders
        lift $ logHttpSuccess logger userInfo reqId req reqBody respBytes compressedResp qTime mCompressionType reqHeaders
        mapM_ setHeader allRespHeaders
        Spock.lazyBytes compressedResp

v1QueryHandler
  :: (HasVersion, MonadIO m, MonadBaseControl IO m, MetadataApiAuthorization m)
  => RQLQuery -> Handler m (HttpResponse EncJSON)
v1QueryHandler query = do
  userInfo <- asks hcUser
  authorizeMetadataApi query userInfo
  scRef <- scCacheRef . hcServerCtx <$> ask
  logger <- scLogger . hcServerCtx <$> ask
  res <- bool (fst <$> dbAction) (withSCUpdate scRef logger dbAction) $
         queryModifiesSchemaCache query
  return $ HttpResponse res []
  where
    -- Hit postgres
    dbAction = do
      userInfo <- asks hcUser
      scRef <- scCacheRef . hcServerCtx <$> ask
      schemaCache <- fmap fst $ liftIO $ readIORef $ _scrCache scRef
      httpMgr <- scManager . hcServerCtx <$> ask
      sqlGenCtx <- scSQLGenCtx . hcServerCtx <$> ask
      pgExecCtx <- scPGExecCtx . hcServerCtx <$> ask
      instanceId <- scInstanceId . hcServerCtx <$> ask
      runQuery pgExecCtx instanceId userInfo schemaCache httpMgr sqlGenCtx (SystemDefined False) query

v1Alpha1GQHandler
  :: (HasVersion, MonadIO m)
  => GH.GQLBatchedReqs GH.GQLQueryText -> Handler m (HttpResponse EncJSON)
v1Alpha1GQHandler query = do
  userInfo <- asks hcUser
  reqHeaders <- asks hcReqHeaders
  manager <- scManager . hcServerCtx <$> ask
  scRef <- scCacheRef . hcServerCtx <$> ask
  (sc, scVer) <- liftIO $ readIORef $ _scrCache scRef
  pgExecCtx <- scPGExecCtx . hcServerCtx <$> ask
  sqlGenCtx <- scSQLGenCtx . hcServerCtx <$> ask
  planCache <- scPlanCache . hcServerCtx <$> ask
  enableAL  <- scEnableAllowlist . hcServerCtx <$> ask
  logger    <- scLogger . hcServerCtx <$> ask
  requestId <- asks hcRequestId
  responseErrorsConfig <- scResponseInternalErrorsConfig . hcServerCtx <$> ask
  let execCtx = E.ExecutionCtx logger sqlGenCtx pgExecCtx planCache
                (lastBuiltSchemaCache sc) scVer manager enableAL
  flip runReaderT execCtx $ GH.runGQBatched requestId responseErrorsConfig userInfo reqHeaders query

v1GQHandler
  :: (HasVersion, MonadIO m)
  => GH.GQLBatchedReqs GH.GQLQueryText -> Handler m (HttpResponse EncJSON)
v1GQHandler = v1Alpha1GQHandler

gqlExplainHandler :: (HasVersion, MonadIO m) => GE.GQLExplain -> Handler m (HttpResponse EncJSON)
gqlExplainHandler query = do
  onlyAdmin
  scRef <- scCacheRef . hcServerCtx <$> ask
  sc <- getSCFromRef scRef
  pgExecCtx <- scPGExecCtx . hcServerCtx <$> ask
  sqlGenCtx <- scSQLGenCtx . hcServerCtx <$> ask
  enableAL <- scEnableAllowlist . hcServerCtx <$> ask
  res <- GE.explainGQLQuery pgExecCtx sc sqlGenCtx enableAL (restrictActionExecuter "query actions cannot be explained") query
  return $ HttpResponse res []

v1Alpha1PGDumpHandler :: (MonadIO m) => PGD.PGDumpReqBody -> Handler m APIResp
v1Alpha1PGDumpHandler b = do
  onlyAdmin
  ci <- scConnInfo . hcServerCtx <$> ask
  output <- PGD.execPGDump b ci
  return $ RawResp $ HttpResponse output [sqlHeader]

consoleAssetsHandler
  :: (MonadIO m, HttpLog m)
  => L.Logger L.Hasura
  -> Text
  -> FilePath
  -> Spock.ActionT m ()
consoleAssetsHandler logger dir path = do
  req <- Spock.request
  let reqHeaders = Wai.requestHeaders req
  -- '..' in paths need not be handed as it is resolved in the url by
  -- spock's routing. we get the expanded path.
  eFileContents <- liftIO $ try $ BL.readFile $
    joinPath [T.unpack dir, path]
  either (onError reqHeaders) onSuccess eFileContents
  where
    onSuccess c = do
      mapM_ setHeader headers
      Spock.lazyBytes c
    onError :: (MonadIO m, HttpLog m) => [HTTP.Header] -> IOException -> Spock.ActionT m ()
    onError hdrs = raiseGenericApiError logger hdrs . err404 NotFound . T.pack . show
    fn = T.pack $ takeFileName path
    -- set gzip header if the filename ends with .gz
    (fileName, encHeader) = case T.stripSuffix ".gz" fn of
      Just v  -> (v, [gzipHeader])
      Nothing -> (fn, [])
    mimeType = defaultMimeLookup fileName
    headers = ("Content-Type", mimeType) : encHeader

class (Monad m) => ConsoleRenderer m where
  renderConsole :: HasVersion => T.Text -> AuthMode -> Bool -> Maybe Text -> m (Either String Text)

renderHtmlTemplate :: M.Template -> Value -> Either String Text
renderHtmlTemplate template jVal =
  bool (Left errMsg) (Right res) $ null errs
  where
    errMsg = "template rendering failed: " ++ show errs
    (errs, res) = M.checkedSubstitute template jVal

newtype LegacyQueryParser m
  = LegacyQueryParser
  { getLegacyQueryParser :: QualifiedTable -> Object -> Handler m RQLQueryV1 }

queryParsers :: (Monad m) => M.HashMap T.Text (LegacyQueryParser m)
queryParsers =
  M.fromList
  [ ("select", mkLegacyQueryParser RQSelect)
  , ("insert", mkLegacyQueryParser RQInsert)
  , ("update", mkLegacyQueryParser RQUpdate)
  , ("delete", mkLegacyQueryParser RQDelete)
  , ("count", mkLegacyQueryParser RQCount)
  ]
  where
    mkLegacyQueryParser f =
      LegacyQueryParser $ \qt obj -> do
      let val = Object $ M.insert "table" (toJSON qt) obj
      q <- decodeValue val
      return $ f q

legacyQueryHandler
  :: (HasVersion, MonadIO m, MonadBaseControl IO m, MetadataApiAuthorization m)
  => TableName -> T.Text -> Object
  -> Handler m (HttpResponse EncJSON)
legacyQueryHandler tn queryType req =
  case M.lookup queryType queryParsers of
    Just queryParser -> getLegacyQueryParser queryParser qt req >>= v1QueryHandler . RQV1
    Nothing          -> throw404 "No such resource exists"
  where
    qt = QualifiedObject publicSchema tn

initErrExit :: QErr -> IO a
initErrExit e = do
  putStrLn $
    "failed to build schema-cache because of inconsistent metadata: "
    <> (show e)
  exitFailure

data HasuraApp
  = HasuraApp
  { _hapApplication    :: !Wai.Application
  , _hapSchemaRef      :: !SchemaCacheRef
  , _hapCacheBuildTime :: !(Maybe UTCTime)
  , _hapShutdown       :: !(IO ())
  }

mkWaiApp
  :: forall m.
     ( HasVersion
     , MonadIO m
     , MonadStateless IO m
     , ConsoleRenderer m
     , HttpLog m
     , UserAuthentication m
     , MetadataApiAuthorization m
     , LA.Forall (LA.Pure m)
     )
  => Q.TxIsolation
  -> L.Logger L.Hasura
  -> SQLGenCtx
  -> Bool
  -> Q.PGPool
  -> Q.ConnInfo
  -> HTTP.Manager
  -> AuthMode
  -> CorsConfig
  -> Bool
  -> Maybe Text
  -> Bool
  -> InstanceId
  -> S.HashSet API
  -> EL.LiveQueriesOptions
  -> E.PlanCacheOptions
  -> ResponseInternalErrorsConfig
  -> m HasuraApp
mkWaiApp isoLevel logger sqlGenCtx enableAL pool ci httpManager mode corsCfg enableConsole consoleAssetsDir
         enableTelemetry instanceId apis lqOpts planCacheOptions responseErrorsConfig = do

    (planCache, schemaCacheRef, cacheBuiltTime) <- migrateAndInitialiseSchemaCache
    let getSchemaCache = first lastBuiltSchemaCache <$> readIORef (_scrCache schemaCacheRef)

    let corsPolicy = mkDefaultCorsPolicy corsCfg
        pgExecCtx = PGExecCtx pool isoLevel
    lqState <- liftIO $ EL.initLiveQueriesState lqOpts pgExecCtx
    wsServerEnv <- WS.createWSServerEnv logger pgExecCtx lqState getSchemaCache httpManager
                                        corsPolicy sqlGenCtx enableAL planCache

    ekgStore <- liftIO EKG.newStore

    let serverCtx = ServerCtx
                    { scPGExecCtx       =  pgExecCtx
                    , scConnInfo        =  ci
                    , scLogger          =  logger
                    , scCacheRef        =  schemaCacheRef
                    , scAuthMode        =  mode
                    , scManager         =  httpManager
                    , scSQLGenCtx       =  sqlGenCtx
                    , scEnabledAPIs     =  apis
                    , scInstanceId      =  instanceId
                    , scPlanCache       =  planCache
                    , scLQState         =  lqState
                    , scEnableAllowlist =  enableAL
                    , scEkgStore        =  ekgStore
                    , scResponseInternalErrorsConfig = responseErrorsConfig
                    }

    when (isDeveloperAPIEnabled serverCtx) $ do
      liftIO $ EKG.registerGcMetrics ekgStore
      liftIO $ EKG.registerCounter "ekg.server_timestamp_ms" getTimeMs ekgStore

    spockApp <- liftWithStateless $ \lowerIO ->
      Spock.spockAsApp $ Spock.spockT lowerIO $ httpApp corsCfg serverCtx enableConsole consoleAssetsDir enableTelemetry

    let wsServerApp = WS.createWSServerApp mode wsServerEnv
        stopWSServer = WS.stopWSServerApp wsServerEnv

    waiApp <- liftWithStateless $ \lowerIO ->
      pure $ WS.websocketsOr WS.defaultConnectionOptions (lowerIO . wsServerApp) spockApp

    return $ HasuraApp waiApp schemaCacheRef cacheBuiltTime stopWSServer
  where
    getTimeMs :: IO Int64
    getTimeMs = (round . (* 1000)) `fmap` getPOSIXTime

    migrateAndInitialiseSchemaCache :: m (E.PlanCache, SchemaCacheRef, Maybe UTCTime)
    migrateAndInitialiseSchemaCache = do
      let pgExecCtx = PGExecCtx pool Q.Serializable
          adminRunCtx = RunCtx adminUserInfo httpManager sqlGenCtx
      currentTime <- liftIO getCurrentTime
      initialiseResult <- runExceptT $ peelRun adminRunCtx pgExecCtx Q.ReadWrite do
        (,) <$> migrateCatalog currentTime <*> liftTx fetchLastUpdate

      ((migrationResult, schemaCache), lastUpdateEvent) <-
        initialiseResult `onLeft` \err -> do
          L.unLogger logger StartupLog
            { slLogLevel = L.LevelError
            , slKind = "db_migrate"
            , slInfo = toJSON err
            }
          liftIO exitFailure
      L.unLogger logger migrationResult

      cacheLock <- liftIO $ newMVar ()
      cacheCell <- liftIO $ newIORef (schemaCache, initSchemaCacheVer)
      planCache <- liftIO $ E.initPlanCache planCacheOptions
      let cacheRef = SchemaCacheRef cacheLock cacheCell (E.clearPlanCache planCache)

      pure (planCache, cacheRef, view _2 <$> lastUpdateEvent)

httpApp
  :: (HasVersion, MonadIO m, MonadBaseControl IO m, ConsoleRenderer m, HttpLog m, UserAuthentication m, MetadataApiAuthorization m)
  => CorsConfig
  -> ServerCtx
  -> Bool
  -> Maybe Text
  -> Bool
  -> Spock.SpockT m ()
httpApp corsCfg serverCtx enableConsole consoleAssetsDir enableTelemetry = do

    -- cors middleware
    unless (isCorsDisabled corsCfg) $
      Spock.middleware $ corsMiddleware (mkDefaultCorsPolicy corsCfg)

    -- API Console and Root Dir
    when (enableConsole && enableMetadata) serveApiConsole

    -- Health check endpoint
    Spock.get "healthz" $ do
      sc <- getSCFromRef $ scCacheRef serverCtx
      dbOk <- checkDbConnection
      if dbOk
        then Spock.setStatus HTTP.status200 >> (Spock.text $ if null (scInconsistentObjs sc)
                                                 then "OK"
                                                 else "WARN: inconsistent objects in schema")
        else Spock.setStatus HTTP.status500 >> Spock.text "ERROR"

    Spock.get "v1/version" $ do
      setHeader jsonHeader
      Spock.lazyBytes $ encode $ object [ "version" .= currentVersion ]

    when enableMetadata $ do

      Spock.post "v1/graphql/explain" gqlExplainAction

      Spock.post "v1alpha1/graphql/explain" gqlExplainAction

      Spock.post "v1/query" $ spockAction encodeQErr id $
        mkPostHandler $ mkAPIRespHandler v1QueryHandler

      Spock.post ("api/1/table" <//> Spock.var <//> Spock.var) $ \tableName queryType ->
        mkSpockAction serverCtx encodeQErr id $ mkPostHandler $
          mkAPIRespHandler $ legacyQueryHandler (TableName tableName) queryType

    when enablePGDump $

      Spock.post "v1alpha1/pg_dump" $ spockAction encodeQErr id $
        mkPostHandler v1Alpha1PGDumpHandler

    when enableConfig $
      Spock.get "v1alpha1/config" $ spockAction encodeQErr id $
        mkGetHandler $ do
          onlyAdmin
          let res = encJFromJValue $ runGetConfig
                      (scAuthMode serverCtx)
                      (scEnableAllowlist serverCtx)
                      (EL._lqsOptions $ scLQState serverCtx)

          return $ JSONResp $ HttpResponse res []

    when enableGraphQL $ do
      Spock.post "v1alpha1/graphql" $ spockAction GH.encodeGQErr id $
        mkPostHandler $ mkAPIRespHandler v1Alpha1GQHandler

      Spock.post "v1/graphql" $ spockAction GH.encodeGQErr allMod200 $
        mkPostHandler $ mkAPIRespHandler v1GQHandler

    when (isDeveloperAPIEnabled serverCtx) $ do
      Spock.get "dev/ekg" $ spockAction encodeQErr id $
        mkGetHandler $ do
          onlyAdmin
          respJ <- liftIO $ EKG.sampleAll $ scEkgStore serverCtx
          return $ JSONResp $ HttpResponse (encJFromJValue $ EKG.sampleToJson respJ) []
      Spock.get "dev/plan_cache" $ spockAction encodeQErr id $
        mkGetHandler $ do
          onlyAdmin
          respJ <- liftIO $ E.dumpPlanCache $ scPlanCache serverCtx
          return $ JSONResp $ HttpResponse (encJFromJValue respJ) []
      Spock.get "dev/subscriptions" $ spockAction encodeQErr id $
        mkGetHandler $ do
          onlyAdmin
          respJ <- liftIO $ EL.dumpLiveQueriesState False $ scLQState serverCtx
          return $ JSONResp $ HttpResponse (encJFromJValue respJ) []
      Spock.get "dev/subscriptions/extended" $ spockAction encodeQErr id $
        mkGetHandler $ do
          onlyAdmin
          respJ <- liftIO $ EL.dumpLiveQueriesState True $ scLQState serverCtx
          return $ JSONResp $ HttpResponse (encJFromJValue respJ) []

    forM_ [Spock.GET, Spock.POST] $ \m -> Spock.hookAny m $ \_ -> do
      req <- Spock.request
      let headers = Wai.requestHeaders req
      let qErr = err404 NotFound "resource does not exist"
      raiseGenericApiError logger headers qErr

  where
    logger = scLogger serverCtx

    spockAction
      :: (FromJSON a, ToJSON a, MonadIO m, UserAuthentication m, HttpLog m)
      => (Bool -> QErr -> Value)
      -> (QErr -> QErr) -> APIHandler m a -> Spock.ActionT m ()
    spockAction = mkSpockAction serverCtx


    -- all graphql errors should be of type 200
    allMod200 qe = qe { qeStatus = HTTP.status200 }

    gqlExplainAction =
      spockAction encodeQErr id $ mkPostHandler $
        mkAPIRespHandler gqlExplainHandler

    enableGraphQL = isGraphQLEnabled serverCtx
    enableMetadata = isMetadataEnabled serverCtx
    enablePGDump = isPGDumpEnabled serverCtx
    enableConfig = isConfigEnabled serverCtx

    checkDbConnection = do
      e <- liftIO $ runExceptT $ runLazyTx' (scPGExecCtx serverCtx) select1Query
      pure $ isRight e
      where
        select1Query :: (MonadTx m) => m Int
        select1Query =   liftTx $ runIdentity . Q.getRow <$> Q.withQE defaultTxErrorHandler
                         [Q.sql| SELECT 1 |] () False

    serveApiConsole = do
      -- redirect / to /console
      Spock.get Spock.root $ Spock.redirect "console"

      -- serve static files if consoleAssetsDir is set
      onJust consoleAssetsDir $ \dir ->
        Spock.get ("console/assets" <//> Spock.wildcard) $ \path ->
          consoleAssetsHandler logger dir (T.unpack path)

      -- serve console html
      Spock.get ("console" <//> Spock.wildcard) $ \path -> do
        req <- Spock.request
        let headers = Wai.requestHeaders req
        let authMode = scAuthMode serverCtx
        consoleHtml <- lift $ renderConsole path authMode enableTelemetry consoleAssetsDir
        either (raiseGenericApiError logger headers . err500 Unexpected . T.pack) Spock.html consoleHtml

raiseGenericApiError
  :: (MonadIO m, HttpLog m)
  => L.Logger L.Hasura
  -> [HTTP.Header]
  -> QErr
  -> Spock.ActionT m ()
raiseGenericApiError logger headers qErr = do
  req <- Spock.request
  reqBody <- liftIO $ Wai.strictRequestBody req
  reqId <- getRequestId $ Wai.requestHeaders req
  lift $ logHttpError logger Nothing reqId req (Left reqBody) qErr headers
  setHeader jsonHeader
  Spock.setStatus $ qeStatus qErr
  Spock.lazyBytes $ encode qErr