graphql-engine/server/src-lib/Hasura/RQL/DML/Select.hs
hasura-bot 64743cb189 server: all remaining IR changes (#75)
Co-authored-by: Antoine Leblanc <antoine@hasura.io>
GITHUB_PR_NUMBER: 6233
GITHUB_PR_URL: https://github.com/hasura/graphql-engine/pull/6233

Co-authored-by: Antoine Leblanc <antoine@hasura.io>
Co-authored-by: Auke Booij <auke@hasura.io>
GitOrigin-RevId: 268cdad529ad5d9bebeb5b881fda5413ea9d7715
2020-11-25 14:19:50 +00:00

334 lines
12 KiB
Haskell

module Hasura.RQL.DML.Select
( selectP2
, convSelectQuery
, runSelect
)
where
import Hasura.Prelude
import qualified Data.HashSet as HS
import qualified Data.List.NonEmpty as NE
import qualified Data.Sequence as DS
import qualified Database.PG.Query as Q
import Data.Aeson.Types
import Data.Text.Extended
import Instances.TH.Lift ()
import Language.Haskell.TH.Syntax (Lift)
import qualified Hasura.Backends.Postgres.SQL.DML as S
import Hasura.Backends.Postgres.SQL.Types
import Hasura.Backends.Postgres.Translate.Select
import Hasura.EncJSON
import Hasura.RQL.DML.Internal
import Hasura.RQL.DML.Types
import Hasura.RQL.IR.OrderBy
import Hasura.RQL.IR.Select
import Hasura.RQL.Types
import Hasura.SQL.Types
type SelectQExt b = SelectG (ExtCol b) (BoolExp b) Int
-- Columns in RQL
-- This technically doesn't need to be generalized to all backends as
-- it is specific to this module; however the generalization work was
-- already done, and there's no particular reason to force this to be
-- specific.
data ExtCol (b :: BackendType)
= ECSimple !(Column b)
| ECRel !RelName !(Maybe RelName) !(SelectQExt b)
deriving instance Lift (ExtCol 'Postgres)
instance ToJSON (ExtCol 'Postgres) where
toJSON (ECSimple s) = toJSON s
toJSON (ECRel rn mrn selq) =
object $ [ "name" .= rn
, "alias" .= mrn
] ++ selectGToPairs selq
instance FromJSON (ExtCol 'Postgres) where
parseJSON v@(Object o) =
ECRel
<$> o .: "name"
<*> o .:? "alias"
<*> parseJSON v
parseJSON v@(String _) =
ECSimple <$> parseJSON v
parseJSON _ =
fail $ mconcat
[ "A column should either be a string or an "
, "object (relationship)"
]
convSelCol :: (UserInfoM m, QErrM m, CacheRM m)
=> FieldInfoMap (FieldInfo 'Postgres)
-> SelPermInfo 'Postgres
-> SelCol 'Postgres
-> m [ExtCol 'Postgres]
convSelCol _ _ (SCExtSimple cn) =
return [ECSimple cn]
convSelCol fieldInfoMap _ (SCExtRel rn malias selQ) = do
-- Point to the name key
let pgWhenRelErr = "only relationships can be expanded"
relInfo <- withPathK "name" $
askRelType fieldInfoMap rn pgWhenRelErr
let (RelInfo _ _ _ relTab _ _) = relInfo
(rfim, rspi) <- fetchRelDet rn relTab
resolvedSelQ <- resolveStar rfim rspi selQ
return [ECRel rn malias resolvedSelQ]
convSelCol fieldInfoMap spi (SCStar wildcard) =
convWildcard fieldInfoMap spi wildcard
convWildcard
:: (UserInfoM m, QErrM m, CacheRM m)
=> FieldInfoMap (FieldInfo 'Postgres)
-> SelPermInfo 'Postgres
-> Wildcard
-> m [ExtCol 'Postgres]
convWildcard fieldInfoMap selPermInfo wildcard =
case wildcard of
Star -> return simpleCols
(StarDot wc) -> (simpleCols ++) <$> (catMaybes <$> relExtCols wc)
where
cols = spiCols selPermInfo
pgCols = map pgiColumn $ getCols fieldInfoMap
relColInfos = getRels fieldInfoMap
simpleCols = map ECSimple $ filter (`HS.member` cols) pgCols
mkRelCol wc relInfo = do
let relName = riName relInfo
relTab = riRTable relInfo
relTabInfo <- fetchRelTabInfo relTab
mRelSelPerm <- askPermInfo' PASelect relTabInfo
forM mRelSelPerm $ \rspi -> do
rExtCols <- convWildcard (_tciFieldInfoMap $ _tiCoreInfo relTabInfo) rspi wc
return $ ECRel relName Nothing $
SelectG rExtCols Nothing Nothing Nothing Nothing
relExtCols wc = mapM (mkRelCol wc) relColInfos
resolveStar :: (UserInfoM m, QErrM m, CacheRM m)
=> FieldInfoMap (FieldInfo 'Postgres)
-> SelPermInfo 'Postgres
-> SelectQ 'Postgres
-> m (SelectQExt 'Postgres)
resolveStar fim spi (SelectG selCols mWh mOb mLt mOf) = do
procOverrides <- fmap (concat . catMaybes) $ withPathK "columns" $
indexedForM selCols $ \selCol -> case selCol of
(SCStar _) -> return Nothing
_ -> Just <$> convSelCol fim spi selCol
everything <- case wildcards of
[] -> return []
_ -> convWildcard fim spi $ maximum wildcards
let extCols = unionBy equals procOverrides everything
return $ SelectG extCols mWh mOb mLt mOf
where
wildcards = lefts $ map mkEither selCols
mkEither (SCStar wc) = Left wc
mkEither selCol = Right selCol
equals (ECSimple x) (ECSimple y) = x == y
equals (ECRel x _ _) (ECRel y _ _) = x == y
equals _ _ = False
convOrderByElem
:: (UserInfoM m, QErrM m, CacheRM m)
=> SessVarBldr 'Postgres m
-> (FieldInfoMap (FieldInfo 'Postgres), SelPermInfo 'Postgres)
-> OrderByCol
-> m (AnnOrderByElement 'Postgres S.SQLExp)
convOrderByElem sessVarBldr (flds, spi) = \case
OCPG fldName -> do
fldInfo <- askFieldInfo flds fldName
case fldInfo of
FIColumn colInfo -> do
checkSelOnCol spi (pgiColumn colInfo)
let ty = pgiType colInfo
if isScalarColumnWhere isGeoType ty
then throw400 UnexpectedPayload $ mconcat
[ fldName <<> " has type 'geometry'"
, " and cannot be used in order_by"
]
else return $ AOCColumn colInfo
FIRelationship _ -> throw400 UnexpectedPayload $ mconcat
[ fldName <<> " is a"
, " relationship and should be expanded"
]
FIComputedField _ -> throw400 UnexpectedPayload $ mconcat
[ fldName <<> " is a"
, " computed field and can't be used in 'order_by'"
]
-- TODO Rakesh (from master)
FIRemoteRelationship {} ->
throw400 UnexpectedPayload (mconcat [ fldName <<> " is a remote field" ])
OCRel fldName rest -> do
fldInfo <- askFieldInfo flds fldName
case fldInfo of
FIColumn _ -> throw400 UnexpectedPayload $ mconcat
[ fldName <<> " is a Postgres column"
, " and cannot be chained further"
]
FIComputedField _ -> throw400 UnexpectedPayload $ mconcat
[ fldName <<> " is a"
, " computed field and can't be used in 'order_by'"
]
FIRelationship relInfo -> do
when (riType relInfo == ArrRel) $
throw400 UnexpectedPayload $ mconcat
[ fldName <<> " is an array relationship"
," and can't be used in 'order_by'"
]
(relFim, relSpi) <- fetchRelDet (riName relInfo) (riRTable relInfo)
resolvedSelFltr <- convAnnBoolExpPartialSQL sessVarBldr $ spiFilter relSpi
AOCObjectRelation relInfo resolvedSelFltr <$>
convOrderByElem sessVarBldr (relFim, relSpi) rest
FIRemoteRelationship {} ->
throw400 UnexpectedPayload (mconcat [ fldName <<> " is a remote field" ])
convSelectQ
:: (UserInfoM m, QErrM m, CacheRM m, HasSQLGenCtx m)
=> QualifiedTable
-> FieldInfoMap (FieldInfo 'Postgres) -- Table information of current table
-> SelPermInfo 'Postgres -- Additional select permission info
-> SelectQExt 'Postgres -- Given Select Query
-> SessVarBldr 'Postgres m
-> (ColumnType 'Postgres -> Value -> m S.SQLExp)
-> m (AnnSimpleSel 'Postgres)
convSelectQ table fieldInfoMap selPermInfo selQ sessVarBldr prepValBldr = do
annFlds <- withPathK "columns" $
indexedForM (sqColumns selQ) $ \case
(ECSimple pgCol) -> do
colInfo <- convExtSimple fieldInfoMap selPermInfo pgCol
return (fromPGCol pgCol, mkAnnColumnField colInfo Nothing)
(ECRel relName mAlias relSelQ) -> do
annRel <- convExtRel fieldInfoMap relName mAlias
relSelQ sessVarBldr prepValBldr
return ( fromRel $ fromMaybe relName mAlias
, either AFObjectRelation AFArrayRelation annRel
)
-- Convert where clause
wClause <- forM (sqWhere selQ) $ \be ->
withPathK "where" $
convBoolExp fieldInfoMap selPermInfo be sessVarBldr prepValBldr
annOrdByML <- forM (sqOrderBy selQ) $ \(OrderByExp obItems) ->
withPathK "order_by" $ indexedForM obItems $ mapM $
convOrderByElem sessVarBldr (fieldInfoMap, selPermInfo)
let annOrdByM = NE.nonEmpty =<< annOrdByML
-- validate limit and offset values
withPathK "limit" $ mapM_ onlyPositiveInt mQueryLimit
withPathK "offset" $ mapM_ onlyPositiveInt mQueryOffset
resolvedSelFltr <- convAnnBoolExpPartialSQL sessVarBldr $
spiFilter selPermInfo
let tabFrom = FromTable table
tabPerm = TablePerm resolvedSelFltr mPermLimit
tabArgs = SelectArgs wClause annOrdByM mQueryLimit
(S.intToSQLExp <$> mQueryOffset) Nothing
strfyNum <- stringifyNum <$> askSQLGenCtx
return $ AnnSelectG annFlds tabFrom tabPerm tabArgs strfyNum
where
mQueryOffset = sqOffset selQ
mQueryLimit = sqLimit selQ
mPermLimit = spiLimit selPermInfo
convExtSimple
:: (UserInfoM m, QErrM m)
=> FieldInfoMap (FieldInfo 'Postgres)
-> SelPermInfo 'Postgres
-> PGCol
-> m (ColumnInfo 'Postgres)
convExtSimple fieldInfoMap selPermInfo pgCol = do
checkSelOnCol selPermInfo pgCol
askPGColInfo fieldInfoMap pgCol relWhenPGErr
where
relWhenPGErr = "relationships have to be expanded"
convExtRel
:: (UserInfoM m, QErrM m, CacheRM m, HasSQLGenCtx m)
=> FieldInfoMap (FieldInfo 'Postgres)
-> RelName
-> Maybe RelName
-> SelectQExt 'Postgres
-> SessVarBldr 'Postgres m
-> (ColumnType 'Postgres -> Value -> m S.SQLExp)
-> m (Either (ObjectRelationSelect 'Postgres) (ArraySelect 'Postgres))
convExtRel fieldInfoMap relName mAlias selQ sessVarBldr prepValBldr = do
-- Point to the name key
relInfo <- withPathK "name" $
askRelType fieldInfoMap relName pgWhenRelErr
let (RelInfo _ relTy colMapping relTab _ _) = relInfo
(relCIM, relSPI) <- fetchRelDet relName relTab
annSel <- convSelectQ relTab relCIM relSPI selQ sessVarBldr prepValBldr
case relTy of
ObjRel -> do
when misused $ throw400 UnexpectedPayload objRelMisuseMsg
return $ Left $ AnnRelationSelectG (fromMaybe relName mAlias) colMapping $
AnnObjectSelectG (_asnFields annSel) relTab $ _tpFilter $ _asnPerm annSel
ArrRel ->
return $ Right $ ASSimple $ AnnRelationSelectG (fromMaybe relName mAlias)
colMapping annSel
where
pgWhenRelErr = "only relationships can be expanded"
misused =
or [ isJust (sqWhere selQ)
, isJust (sqLimit selQ)
, isJust (sqOffset selQ)
, isJust (sqOrderBy selQ)
]
objRelMisuseMsg =
mconcat [ "when selecting an 'obj_relationship' "
, "'where', 'order_by', 'limit' and 'offset' "
, " can't be used"
]
convSelectQuery
:: (UserInfoM m, QErrM m, CacheRM m, HasSQLGenCtx m)
=> SessVarBldr 'Postgres m
-> (ColumnType 'Postgres -> Value -> m S.SQLExp)
-> SelectQuery
-> m (AnnSimpleSel 'Postgres)
convSelectQuery sessVarBldr prepArgBuilder (DMLQuery qt selQ) = do
tabInfo <- withPathK "table" $ askTabInfo qt
selPermInfo <- askSelPermInfo tabInfo
let fieldInfo = _tciFieldInfoMap $ _tiCoreInfo tabInfo
extSelQ <- resolveStar fieldInfo selPermInfo selQ
validateHeaders $ spiRequiredHeaders selPermInfo
convSelectQ qt fieldInfo selPermInfo extSelQ sessVarBldr prepArgBuilder
selectP2 :: JsonAggSelect -> (AnnSimpleSel 'Postgres, DS.Seq Q.PrepArg) -> Q.TxE QErr EncJSON
selectP2 jsonAggSelect (sel, p) =
encJFromBS . runIdentity . Q.getRow
<$> Q.rawQE dmlTxErrorHandler (Q.fromBuilder selectSQL) (toList p) True
where
selectSQL = toSQL $ mkSQLSelect jsonAggSelect sel
phaseOne
:: (QErrM m, UserInfoM m, CacheRM m, HasSQLGenCtx m)
=> SelectQuery -> m (AnnSimpleSel 'Postgres, DS.Seq Q.PrepArg)
phaseOne =
runDMLP1T . convSelectQuery sessVarFromCurrentSetting binRHSBuilder
phaseTwo :: (MonadTx m) => (AnnSimpleSel 'Postgres, DS.Seq Q.PrepArg) -> m EncJSON
phaseTwo =
liftTx . selectP2 JASMultipleRows
runSelect
:: (QErrM m, UserInfoM m, CacheRM m, HasSQLGenCtx m, MonadTx m)
=> SelectQuery -> m EncJSON
runSelect q =
phaseOne q >>= phaseTwo