graphql-engine/server/src-lib/Hasura/GraphQL/Schema/OrderBy.hs
Antoine Leblanc 512a4dbb92 Use a different reader context for sources and remote schemas with new SchemaT monad.
### Description

This PR changes all the schema code to operate in a specific `SchemaT` monad, rather than in an arbitrary `m` monad. `SchemaT` is intended to be used opaquely with `runSourceSchema` and `runRemoteSchema`. The main goal of this is to allow a different reader context per part of the schema: this PR also minimizes the contexts. This means that we no longer require `SchemaOptions` when building remote schemas' schema, and this PR therefore removes a lot of dummy / placeholder values accordingly.

### Performance and stacking

This PR has been through several iterations. #5339 was the original version, that accomplished the same thing by stacking readers on top of the stack at every remote relationship boundary. This raised performance concerns, and @0x777 confirmed with an ad-hoc test that in some extreme cases we could see up to a 10% performance impact. This version, while more verbose, allows us to unstack / re-stack the readers, and avoid that problem. #5517 adds a new benchmark set to be able to automatically measure this on every PR.

### Remaining work

- [x] a comment (or perhaps even a Note?) should be added to `SchemaT`
- [x] we probably want for #5517 to be merged first so that we can confirm the lack of performance penalty

PR-URL: https://github.com/hasura/graphql-engine-mono/pull/5458
GitOrigin-RevId: e06b83d90da475f745b838f1fd8f8b4d9d3f4b10
2022-09-06 16:49:23 +00:00

255 lines
11 KiB
Haskell

{-# LANGUAGE ApplicativeDo #-}
{-# LANGUAGE TemplateHaskellQuotes #-}
module Hasura.GraphQL.Schema.OrderBy
( orderByExp,
)
where
import Data.Has
import Data.Text.Casing qualified as C
import Data.Text.Extended
import Hasura.GraphQL.Parser.Class
import Hasura.GraphQL.Schema.Backend
import Hasura.GraphQL.Schema.Common
import Hasura.GraphQL.Schema.NamingCase
import Hasura.GraphQL.Schema.Parser
( InputFieldsParser,
Kind (..),
Parser,
)
import Hasura.GraphQL.Schema.Parser qualified as P
import Hasura.GraphQL.Schema.Table
import Hasura.GraphQL.Schema.Typename
import Hasura.Name qualified as Name
import Hasura.Prelude
import Hasura.RQL.IR.OrderBy qualified as IR
import Hasura.RQL.IR.Select qualified as IR
import Hasura.RQL.IR.Value qualified as IR
import Hasura.RQL.Types.Backend
import Hasura.RQL.Types.Column
import Hasura.RQL.Types.Common
import Hasura.RQL.Types.ComputedField
import Hasura.RQL.Types.Function
import Hasura.RQL.Types.Relationships.Local
import Hasura.RQL.Types.SchemaCache hiding (askTableInfo)
import Hasura.RQL.Types.Source
import Hasura.RQL.Types.SourceCustomization
import Hasura.RQL.Types.Table
import Language.GraphQL.Draft.Syntax qualified as G
{-# INLINE orderByOperator #-}
orderByOperator ::
forall b n.
(BackendSchema b, MonadParse n) =>
NamingCase ->
SourceInfo b ->
Parser 'Both n (Maybe (BasicOrderType b, NullsOrderType b))
orderByOperator tCase sourceInfo = case tCase of
HasuraCase -> orderByOperatorsHasuraCase @b sourceInfo
GraphqlCase -> orderByOperatorsGraphqlCase @b sourceInfo
-- | Corresponds to an object type for an order by.
--
-- > input table_order_by {
-- > col1: order_by
-- > col2: order_by
-- > . .
-- > . .
-- > coln: order_by
-- > obj-rel: <remote-table>_order_by
-- > }
orderByExp ::
forall b r m n.
MonadBuildSchema b r m n =>
SourceInfo b ->
TableInfo b ->
SchemaT r m (Parser 'Input n [IR.AnnotatedOrderByItemG b (IR.UnpreparedValue b)])
orderByExp sourceInfo tableInfo = P.memoizeOn 'orderByExp (_siName sourceInfo, tableInfoName tableInfo) $ do
tCase <- asks getter
tableGQLName <- getTableIdentifierName tableInfo
name <- mkTypename $ applyTypeNameCaseIdentifier tCase $ mkTableOrderByTypeName tableGQLName
let description =
G.Description $
"Ordering options when selecting data from " <> tableInfoName tableInfo <<> "."
tableFields <- tableSelectFields sourceInfo tableInfo
fieldParsers <- sequenceA . catMaybes <$> traverse (mkField tCase) tableFields
pure $ concat . catMaybes <$> P.object name (Just description) fieldParsers
where
mkField ::
NamingCase ->
FieldInfo b ->
SchemaT r m (Maybe (InputFieldsParser n (Maybe [IR.AnnotatedOrderByItemG b (IR.UnpreparedValue b)])))
mkField tCase fieldInfo = runMaybeT $ do
roleName <- retrieve scRole
case fieldInfo of
FIColumn columnInfo -> do
let fieldName = ciName columnInfo
pure $
P.fieldOptional
fieldName
Nothing
(orderByOperator @b tCase sourceInfo)
<&> fmap (pure . mkOrderByItemG @b (IR.AOCColumn columnInfo)) . join
FIRelationship relationshipInfo -> do
remoteTableInfo <- askTableInfo sourceInfo $ riRTable relationshipInfo
perms <- hoistMaybe $ tableSelectPermissions roleName remoteTableInfo
fieldName <- hoistMaybe $ G.mkName $ relNameToTxt $ riName relationshipInfo
let newPerms = fmap partialSQLExpToUnpreparedValue <$> spiFilter perms
case riType relationshipInfo of
ObjRel -> do
otherTableParser <- lift $ orderByExp sourceInfo remoteTableInfo
pure $ do
otherTableOrderBy <- join <$> P.fieldOptional fieldName Nothing (P.nullable otherTableParser)
pure $ fmap (map $ fmap $ IR.AOCObjectRelation relationshipInfo newPerms) otherTableOrderBy
ArrRel -> do
let aggregateFieldName = applyFieldNameCaseIdentifier tCase $ C.fromAutogeneratedTuple (fieldName, [G.convertNameToSuffix Name._aggregate])
aggregationParser <- lift $ orderByAggregation sourceInfo remoteTableInfo
pure $ do
aggregationOrderBy <- join <$> P.fieldOptional aggregateFieldName Nothing (P.nullable aggregationParser)
pure $ fmap (map $ fmap $ IR.AOCArrayAggregation relationshipInfo newPerms) aggregationOrderBy
FIComputedField ComputedFieldInfo {..} -> do
let ComputedFieldFunction {..} = _cfiFunction
mkComputedFieldOrderBy =
let functionArgs =
flip FunctionArgsExp mempty $
fromComputedFieldImplicitArguments @b IR.UVSession _cffComputedFieldImplicitArgs
in IR.ComputedFieldOrderBy _cfiXComputedFieldInfo _cfiName _cffName functionArgs
fieldName <- hoistMaybe $ G.mkName $ toTxt _cfiName
guard $ _cffInputArgs == mempty -- No input arguments other than table row and session argument
case computedFieldReturnType @b _cfiReturnType of
ReturnsScalar scalarType -> do
let computedFieldOrderBy = mkComputedFieldOrderBy $ IR.CFOBEScalar scalarType
pure $
P.fieldOptional
fieldName
Nothing
(orderByOperator @b tCase sourceInfo)
<&> fmap (pure . mkOrderByItemG @b (IR.AOCComputedField computedFieldOrderBy)) . join
ReturnsTable table -> do
let aggregateFieldName = applyFieldNameCaseIdentifier tCase $ C.fromAutogeneratedTuple (fieldName, [G.convertNameToSuffix Name._aggregate])
tableInfo' <- askTableInfo sourceInfo table
perms <- hoistMaybe $ tableSelectPermissions roleName tableInfo'
let newPerms = fmap partialSQLExpToUnpreparedValue <$> spiFilter perms
aggregationParser <- lift $ orderByAggregation sourceInfo tableInfo'
pure $ do
aggregationOrderBy <- join <$> P.fieldOptional aggregateFieldName Nothing (P.nullable aggregationParser)
pure $
fmap
( map $
fmap $
IR.AOCComputedField
. mkComputedFieldOrderBy
. IR.CFOBETableAggregation table newPerms
)
aggregationOrderBy
ReturnsOthers -> empty
FIRemoteRelationship _ -> empty
-- FIXME!
-- those parsers are directly using Postgres' SQL representation of
-- order, rather than using a general intermediary representation
orderByAggregation ::
forall b r m n.
MonadBuildSchema b r m n =>
SourceInfo b ->
TableInfo b ->
SchemaT r m (Parser 'Input n [IR.OrderByItemG b (IR.AnnotatedAggregateOrderBy b)])
orderByAggregation sourceInfo tableInfo = P.memoizeOn 'orderByAggregation (_siName sourceInfo, tableName) do
-- WIP NOTE
-- there is heavy duplication between this and Select.tableAggregationFields
-- it might be worth putting some of it in common, just to avoid issues when
-- we change one but not the other?
tableGQLName <- getTableGQLName @b tableInfo
tCase <- asks getter
tableIdentifierName <- getTableIdentifierName @b tableInfo
allColumns <- tableSelectColumns sourceInfo tableInfo
makeTypename <- asks getter
let numColumns = onlyNumCols allColumns
compColumns = onlyComparableCols allColumns
numFields = catMaybes <$> traverse (mkField tCase) numColumns
compFields = catMaybes <$> traverse (mkField tCase) compColumns
aggFields =
fmap (concat . catMaybes . concat) $
sequenceA $
catMaybes
[ -- count
Just $
P.fieldOptional
Name._count
Nothing
(orderByOperator @b tCase sourceInfo)
<&> pure . fmap (pure . mkOrderByItemG @b IR.AAOCount) . join,
-- operators on numeric columns
if null numColumns
then Nothing
else Just $
for numericAggOperators \operator ->
parseOperator makeTypename operator tableGQLName numFields,
-- operators on comparable columns
if null compColumns
then Nothing
else Just $
for comparisonAggOperators \operator ->
parseOperator makeTypename operator tableGQLName compFields
]
objectName <- mkTypename $ applyTypeNameCaseIdentifier tCase $ mkTableAggregateOrderByTypeName tableIdentifierName
let description = G.Description $ "order by aggregate values of table " <>> tableName
pure $ P.object objectName (Just description) aggFields
where
tableName = tableInfoName tableInfo
mkField :: NamingCase -> ColumnInfo b -> InputFieldsParser n (Maybe (ColumnInfo b, (BasicOrderType b, NullsOrderType b)))
mkField tCase columnInfo =
P.fieldOptional
(ciName columnInfo)
(ciDescription columnInfo)
(orderByOperator @b tCase sourceInfo)
<&> fmap (columnInfo,) . join
parseOperator ::
MkTypename ->
G.Name ->
G.Name ->
InputFieldsParser n [(ColumnInfo b, (BasicOrderType b, NullsOrderType b))] ->
InputFieldsParser n (Maybe [IR.OrderByItemG b (IR.AnnotatedAggregateOrderBy b)])
parseOperator makeTypename operator tableGQLName columns =
let opText = G.unName operator
objectName = runMkTypename makeTypename $ tableGQLName <> Name.__ <> operator <> Name.__order_by
objectDesc = Just $ G.Description $ "order by " <> opText <> "() on columns of table " <>> tableName
in P.fieldOptional operator Nothing (P.object objectName objectDesc columns)
`mapField` map (\(col, info) -> mkOrderByItemG (IR.AAOOp opText col) info)
orderByOperatorsHasuraCase ::
forall b n.
(BackendSchema b, MonadParse n) =>
SourceInfo b ->
Parser 'Both n (Maybe (BasicOrderType b, NullsOrderType b))
orderByOperatorsHasuraCase = orderByOperator' @b HasuraCase
orderByOperatorsGraphqlCase ::
forall b n.
(BackendSchema b, MonadParse n) =>
SourceInfo b ->
Parser 'Both n (Maybe (BasicOrderType b, NullsOrderType b))
orderByOperatorsGraphqlCase = orderByOperator' @b GraphqlCase
orderByOperator' ::
forall b n.
(BackendSchema b, MonadParse n) =>
NamingCase ->
SourceInfo b ->
Parser 'Both n (Maybe (BasicOrderType b, NullsOrderType b))
orderByOperator' tCase sourceInfo =
let (sourcePrefix, orderOperators) = orderByOperators @b sourceInfo tCase
in P.nullable $ P.enum (applyTypeNameCaseCust tCase sourcePrefix) (Just "column ordering options") $ orderOperators
mkOrderByItemG :: forall b a. a -> (BasicOrderType b, NullsOrderType b) -> IR.OrderByItemG b a
mkOrderByItemG column (orderType, nullsOrder) =
IR.OrderByItemG
{ obiType = Just orderType,
obiColumn = column,
obiNulls = Just nullsOrder
}