graphql-engine/server/src-lib/Hasura/Backends/DataConnector/Adapter/Schema.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

250 lines
11 KiB
Haskell

{-# LANGUAGE TemplateHaskell #-}
{-# OPTIONS_GHC -fno-warn-orphans #-}
module Hasura.Backends.DataConnector.Adapter.Schema () where
--------------------------------------------------------------------------------
import Control.Lens ((^.))
import Data.Aeson qualified as J
import Data.Has
import Data.List.NonEmpty qualified as NE
import Data.Text.Casing (GQLNameIdentifier, fromCustomName)
import Data.Text.Extended ((<<>))
import Data.Text.NonEmpty qualified as NET
import Hasura.Backends.DataConnector.API.V0.Capabilities (lookupComparisonInputObjectDefinition)
import Hasura.Backends.DataConnector.Adapter.Backend (CustomBooleanOperator (..))
import Hasura.Backends.DataConnector.Adapter.Types qualified as Adapter
import Hasura.Backends.DataConnector.IR.Aggregate qualified as IR.A
import Hasura.Backends.DataConnector.IR.Column qualified as IR.C
import Hasura.Backends.DataConnector.IR.OrderBy qualified as IR.O
import Hasura.Backends.DataConnector.IR.Scalar.Type qualified as IR.S.T
import Hasura.Backends.DataConnector.IR.Scalar.Value qualified as IR.S.V
import Hasura.Base.Error
import Hasura.GraphQL.Parser.Class
import Hasura.GraphQL.Schema.Backend (BackendSchema (..), BackendTableSelectSchema (..), ComparisonExp, MonadBuildSchema)
import Hasura.GraphQL.Schema.BoolExp qualified as GS.BE
import Hasura.GraphQL.Schema.Build qualified as GS.B
import Hasura.GraphQL.Schema.Common qualified as GS.C
import Hasura.GraphQL.Schema.NamingCase
import Hasura.GraphQL.Schema.Options qualified as Options
import Hasura.GraphQL.Schema.Parser qualified as P
import Hasura.GraphQL.Schema.Select qualified as GS.S
import Hasura.Name qualified as Name
import Hasura.Prelude
import Hasura.RQL.IR.BoolExp qualified as IR
import Hasura.RQL.IR.Select qualified as IR
import Hasura.RQL.IR.Value qualified as IR
import Hasura.RQL.Types.Backend qualified as RQL
import Hasura.RQL.Types.Column qualified as RQL
import Hasura.RQL.Types.Source qualified as RQL
import Hasura.RQL.Types.SourceCustomization qualified as RQL
import Hasura.RQL.Types.Table qualified as RQL
import Hasura.SQL.Backend (BackendType (..))
import Language.GraphQL.Draft.Syntax qualified as GQL
--------------------------------------------------------------------------------
instance BackendSchema 'DataConnector where
-- top level parsers
buildTableQueryAndSubscriptionFields = GS.B.buildTableQueryAndSubscriptionFields
buildTableRelayQueryFields = experimentalBuildTableRelayQueryFields
buildFunctionQueryFields _ _ _ _ _ = pure []
buildFunctionRelayQueryFields _ _ _ _ _ _ = pure []
buildFunctionMutationFields _ _ _ _ _ = pure []
buildTableInsertMutationFields _ _ _ _ _ _ = pure []
buildTableUpdateMutationFields _ _ _ _ _ _ = pure []
buildTableDeleteMutationFields _ _ _ _ _ _ = pure []
buildTableStreamingSubscriptionFields _ _ _ _ _ = pure []
-- backend extensions
relayExtension = Nothing
nodesAggExtension = Just ()
streamSubscriptionExtension = Nothing
-- individual components
columnParser = columnParser'
scalarSelectionArgumentsParser _ = pure Nothing
orderByOperators = orderByOperators'
comparisonExps = comparisonExps'
countTypeInput = countTypeInput'
aggregateOrderByCountType = IR.S.T.Number
computedField =
error "computedField: not implemented for the Data Connector backend."
instance BackendTableSelectSchema 'DataConnector where
tableArguments = tableArgs'
selectTable = GS.S.defaultSelectTable
selectTableAggregate = GS.S.defaultSelectTableAggregate
tableSelectionSet = GS.S.defaultTableSelectionSet
--------------------------------------------------------------------------------
experimentalBuildTableRelayQueryFields ::
MonadBuildSchema 'DataConnector r m n =>
RQL.MkRootFieldName ->
RQL.SourceInfo 'DataConnector ->
RQL.TableName 'DataConnector ->
RQL.TableInfo 'DataConnector ->
GQLNameIdentifier ->
NESeq (RQL.ColumnInfo 'DataConnector) ->
GS.C.SchemaT r m [P.FieldParser n a]
experimentalBuildTableRelayQueryFields _mkRootFieldName _sourceName _tableName _tableInfo _gqlName _pkeyColumns =
pure []
columnParser' ::
(MonadParse n, MonadError QErr m) =>
RQL.ColumnType 'DataConnector ->
GQL.Nullability ->
GS.C.SchemaT r m (P.Parser 'P.Both n (IR.ValueWithOrigin (RQL.ColumnValue 'DataConnector)))
columnParser' columnType (GQL.Nullability isNullable) = do
parser <- case columnType of
RQL.ColumnScalar IR.S.T.String -> pure (J.String <$> P.string)
RQL.ColumnScalar IR.S.T.Number -> pure (J.Number <$> P.scientific)
RQL.ColumnScalar IR.S.T.Bool -> pure (J.Bool <$> P.boolean)
RQL.ColumnScalar (IR.S.T.Custom name) -> do
gqlName <-
GQL.mkName name
`onNothing` throw400 ValidationFailed ("The column type name " <> name <<> " is not a valid GraphQL name")
pure $ P.jsonScalar gqlName (Just "A custom scalar type")
RQL.ColumnEnumReference {} ->
throw400 NotSupported "Enum column type is unsupported by the Data Connector backend"
pure . GS.C.peelWithOrigin . fmap (RQL.ColumnValue columnType) . possiblyNullable $ parser
where
possiblyNullable ::
MonadParse m =>
P.Parser 'P.Both m J.Value ->
P.Parser 'P.Both m J.Value
possiblyNullable
| isNullable = fmap (fromMaybe J.Null) . P.nullable
| otherwise = id
orderByOperators' :: RQL.SourceInfo 'DataConnector -> NamingCase -> (GQL.Name, NonEmpty (P.Definition P.EnumValueInfo, (RQL.BasicOrderType 'DataConnector, RQL.NullsOrderType 'DataConnector)))
orderByOperators' RQL.SourceInfo {_siConfiguration} _tCase =
let dcName = Adapter._scDataConnectorName _siConfiguration
orderBy = fromMaybe Name._order_by $ GQL.mkName $ NET.unNonEmptyText (Adapter.unDataConnectorName dcName) <> "_order_by"
in (orderBy,) $
-- NOTE: NamingCase is not being used here as we don't support naming conventions for this DB
NE.fromList
[ ( define $$(GQL.litName "asc") "in ascending order",
(IR.O.Ascending, ())
),
( define $$(GQL.litName "desc") "in descending order",
(IR.O.Descending, ())
)
]
where
define name desc = P.Definition name (Just desc) Nothing [] P.EnumValueInfo
comparisonExps' ::
forall m n r.
MonadBuildSchema 'DataConnector r m n =>
RQL.SourceInfo 'DataConnector ->
RQL.ColumnType 'DataConnector ->
GS.C.SchemaT r m (P.Parser 'P.Input n [ComparisonExp 'DataConnector])
comparisonExps' sourceInfo columnType = P.memoizeOn 'comparisonExps' (dataConnectorName, columnType) $ do
tCase <- asks getter
collapseIfNull <- GS.C.retrieve Options.soDangerousBooleanCollapse
typedParser <- columnParser' columnType (GQL.Nullability False)
let name = P.getName typedParser <> $$(GQL.litName "_Dynamic_comparison_exp")
desc =
GQL.Description $
"Boolean expression to compare columns of type "
<> P.getName typedParser
<<> ". All fields are combined with logical 'AND'."
columnListParser = fmap IR.openValueOrigin <$> P.list typedParser
customOperators <- (fmap . fmap . fmap) IR.ABackendSpecific <$> mkCustomOperators tCase collapseIfNull (P.getName typedParser)
pure $
P.object name (Just desc) $
fmap catMaybes $
sequenceA $
concat
[ GS.BE.equalityOperators
tCase
collapseIfNull
(IR.mkParameter <$> typedParser)
(mkListLiteral <$> columnListParser),
GS.BE.comparisonOperators
tCase
collapseIfNull
(IR.mkParameter <$> typedParser),
customOperators
]
where
dataConnectorName = sourceInfo ^. RQL.siConfiguration . Adapter.scDataConnectorName
mkListLiteral :: [RQL.ColumnValue 'DataConnector] -> IR.UnpreparedValue 'DataConnector
mkListLiteral columnValues =
IR.UVLiteral . IR.S.V.ArrayLiteral $ RQL.cvValue <$> columnValues
mkCustomOperators ::
NamingCase ->
Options.DangerouslyCollapseBooleans ->
GQL.Name ->
GS.C.SchemaT r m [P.InputFieldsParser n (Maybe (CustomBooleanOperator (IR.UnpreparedValue 'DataConnector)))]
mkCustomOperators tCase collapseIfNull typeName = do
let capabilities = sourceInfo ^. RQL.siConfiguration . Adapter.scCapabilities
case lookupComparisonInputObjectDefinition capabilities typeName of
Nothing -> pure []
Just GQL.InputObjectTypeDefinition {..} -> do
traverse (mkCustomOperator tCase collapseIfNull) _iotdValueDefinitions
mkCustomOperator ::
NamingCase ->
Options.DangerouslyCollapseBooleans ->
GQL.InputValueDefinition ->
GS.C.SchemaT r m (P.InputFieldsParser n (Maybe (CustomBooleanOperator (IR.UnpreparedValue 'DataConnector))))
mkCustomOperator tCase collapseIfNull GQL.InputValueDefinition {..} = do
argParser <- mkArgParser _ivdType
pure $
GS.BE.mkBoolOperator tCase collapseIfNull (fromCustomName _ivdName) _ivdDescription $
CustomBooleanOperator (GQL.unName _ivdName) . Just . Right <$> argParser
mkArgParser :: GQL.GType -> GS.C.SchemaT r m (P.Parser 'P.Both n (IR.UnpreparedValue 'DataConnector))
mkArgParser argType =
fmap IR.mkParameter
<$> columnParser'
(RQL.ColumnScalar $ IR.S.T.fromGQLType $ GQL.getBaseType argType)
(GQL.Nullability $ GQL.isNotNull argType)
tableArgs' ::
forall r m n.
MonadBuildSchema 'DataConnector r m n =>
RQL.SourceInfo 'DataConnector ->
RQL.TableInfo 'DataConnector ->
GS.C.SchemaT r m (P.InputFieldsParser n (IR.SelectArgsG 'DataConnector (IR.UnpreparedValue 'DataConnector)))
tableArgs' sourceName tableInfo = do
whereParser <- GS.S.tableWhereArg sourceName tableInfo
orderByParser <- GS.S.tableOrderByArg sourceName tableInfo
let mkSelectArgs whereArg orderByArg limitArg offsetArg =
IR.SelectArgs
{ _saWhere = whereArg,
_saOrderBy = orderByArg,
_saLimit = limitArg,
_saOffset = offsetArg,
_saDistinct = Nothing
}
pure $
mkSelectArgs
<$> whereParser
<*> orderByParser
<*> GS.S.tableLimitArg
<*> GS.S.tableOffsetArg
countTypeInput' ::
MonadParse n =>
Maybe (P.Parser 'P.Both n IR.C.Name) ->
P.InputFieldsParser n (IR.CountDistinct -> IR.A.CountAggregate)
countTypeInput' = \case
Just columnEnum -> mkCountAggregate <$> P.fieldOptional Name._column Nothing columnEnum
Nothing -> pure $ mkCountAggregate Nothing
where
mkCountAggregate :: Maybe IR.C.Name -> IR.CountDistinct -> IR.A.CountAggregate
mkCountAggregate Nothing _ = IR.A.StarCount
mkCountAggregate (Just column) IR.SelectCountDistinct = IR.A.ColumnDistinctCount column
mkCountAggregate (Just column) IR.SelectCountNonDistinct = IR.A.ColumnCount column