graphql-engine/server/src-lib/Hasura/Backends/DataConnector/Adapter/Schema.hs
Antoine Leblanc 42e5205eb5 server: reduce schema contexts to the bare minimum
### Description

This monster of a PR took way too long. As the title suggests, it reduces the schema context carried in the readers to the very strict minimum. In practice, that means that to build a source, we only require:
  - the global `SchemaContext`
  - the global `SchemaOptions` (soon to be renamed `SchemaSourceOptions`)
  - that source's `SourceInfo`

Furthermore, _we no longer carry "default" customization options throughout the schema_. All customization information is extracted from the `SourceInfo`, when required. This prevents an entire category of bugs we had previously encountered, such as parts of the code using uninitialized / unupdated customization info.

In turn, this meant that we could remove the explicit threading of the `SourceInfo` throughout the schema, since it is now always available through the reader context.

Finally, this meant making a few adjustments to relay and actions as well, such as the introduction of a new separate "context" for actions, and a change to how we create some of the action-specific postgres scalar parsers.

I'll highlight with review comments the areas of interest.

PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6709
GitOrigin-RevId: ea80fddcb24e2513779dd04b0b700a55f0028dd1
2022-11-17 10:35:54 +00:00

264 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.HashMap.Strict qualified as Map
import Data.List.NonEmpty qualified as NE
import Data.Text.Casing (GQLNameIdentifier, fromCustomName)
import Data.Text.Extended ((<<>))
import Hasura.Backends.DataConnector.API qualified as API
import Hasura.Backends.DataConnector.Adapter.Backend (CustomBooleanOperator (..), columnTypeToScalarType)
import Hasura.Backends.DataConnector.Adapter.Types qualified as DC
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
import Witch qualified
--------------------------------------------------------------------------------
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'
enumParser = enumParser'
possiblyNullable = possiblyNullable'
scalarSelectionArgumentsParser _ = pure Nothing
orderByOperators = orderByOperators'
comparisonExps = comparisonExps'
countTypeInput = countTypeInput'
aggregateOrderByCountType = DC.NumberTy
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.TableName 'DataConnector ->
RQL.TableInfo 'DataConnector ->
GQLNameIdentifier ->
NESeq (RQL.ColumnInfo 'DataConnector) ->
GS.C.SchemaT r m [P.FieldParser n a]
experimentalBuildTableRelayQueryFields _mkRootFieldName _tableName _tableInfo _gqlName _pkeyColumns =
pure []
columnParser' ::
MonadBuildSchema 'DataConnector r m n =>
RQL.ColumnType 'DataConnector ->
GQL.Nullability ->
GS.C.SchemaT r m (P.Parser 'P.Both n (IR.ValueWithOrigin (RQL.ColumnValue 'DataConnector)))
columnParser' columnType nullability = case columnType of
RQL.ColumnScalar scalarType ->
P.memoizeOn 'columnParser' (scalarType, nullability) $
GS.C.peelWithOrigin . fmap (RQL.ColumnValue columnType) . possiblyNullable' scalarType nullability
<$> case scalarType of
DC.StringTy -> pure $ J.String <$> P.string
DC.NumberTy -> pure $ J.Number <$> P.scientific
DC.BoolTy -> pure $ J.Bool <$> P.boolean
DC.CustomTy 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 (RQL.EnumReference tableName enumValues customTableName) ->
case nonEmpty (Map.toList enumValues) of
Just enumValuesList ->
GS.C.peelWithOrigin . fmap (RQL.ColumnValue columnType)
<$> enumParser' tableName enumValuesList customTableName nullability
Nothing -> throw400 ValidationFailed "empty enum values"
enumParser' ::
MonadError QErr m =>
RQL.TableName 'DataConnector ->
NonEmpty (RQL.EnumValue, RQL.EnumValueInfo) ->
Maybe GQL.Name ->
GQL.Nullability ->
GS.C.SchemaT r m (P.Parser 'P.Both n (RQL.ScalarValue 'DataConnector))
enumParser' _tableName _enumValues _customTableName _nullability =
throw400 NotSupported "This column type is unsupported by the Data Connector backend"
possiblyNullable' ::
MonadParse m =>
RQL.ScalarType 'DataConnector ->
GQL.Nullability ->
P.Parser 'P.Both m J.Value ->
P.Parser 'P.Both m J.Value
possiblyNullable' _scalarType (GQL.Nullability isNullable)
| 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 = DC._scDataConnectorName _siConfiguration
orderBy = GQL.addSuffixes (DC.unDataConnectorName dcName) [$$(GQL.litSuffix "_order_by")]
in (orderBy,) $
-- NOTE: NamingCase is not being used here as we don't support naming conventions for this DB
NE.fromList
[ ( define $$(GQL.litName "asc") "in ascending order",
(DC.Ascending, ())
),
( define $$(GQL.litName "desc") "in descending order",
(DC.Descending, ())
)
]
where
define name desc = P.Definition name (Just desc) Nothing [] P.EnumValueInfo
comparisonExps' ::
forall m n r.
MonadBuildSchema 'DataConnector r m n =>
RQL.ColumnType 'DataConnector ->
GS.C.SchemaT r m (P.Parser 'P.Input n [ComparisonExp 'DataConnector])
comparisonExps' columnType = do
collapseIfNull <- GS.C.retrieve Options.soDangerousBooleanCollapse
sourceInfo :: RQL.SourceInfo 'DataConnector <- asks getter
let dataConnectorName = sourceInfo ^. RQL.siConfiguration . DC.scDataConnectorName
tCase = RQL._rscNamingConvention $ RQL._siCustomization sourceInfo
P.memoizeOn 'comparisonExps' (dataConnectorName, columnType) do
typedParser <- columnParser' columnType (GQL.Nullability False)
let name = GQL.addSuffixes (P.getName typedParser) [$$(GQL.litSuffix "_"), GQL.convertNameToSuffix (DC.unDataConnectorName dataConnectorName), $$(GQL.litSuffix "_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 sourceInfo 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
mkListLiteral :: [RQL.ColumnValue 'DataConnector] -> IR.UnpreparedValue 'DataConnector
mkListLiteral columnValues =
IR.UVLiteral $ DC.ArrayLiteral (columnTypeToScalarType columnType) (RQL.cvValue <$> columnValues)
mkCustomOperators ::
RQL.SourceInfo 'DataConnector ->
NamingCase ->
Options.DangerouslyCollapseBooleans ->
GQL.Name ->
GS.C.SchemaT r m [P.InputFieldsParser n (Maybe (CustomBooleanOperator (IR.UnpreparedValue 'DataConnector)))]
mkCustomOperators sourceInfo tCase collapseIfNull typeName = do
let capabilities = sourceInfo ^. RQL.siConfiguration . DC.scCapabilities
case Map.lookup (Witch.from $ DC.fromGQLType typeName) (API.unScalarTypesCapabilities $ API._cScalarTypes capabilities) of
Nothing -> pure []
Just API.ScalarTypeCapabilities {..} -> do
traverse (mkCustomOperator tCase collapseIfNull) $ Map.toList $ fmap Witch.from $ API.unComparisonOperators $ _stcComparisonOperators
mkCustomOperator ::
NamingCase ->
Options.DangerouslyCollapseBooleans ->
(GQL.Name, DC.ScalarType) ->
GS.C.SchemaT r m (P.InputFieldsParser n (Maybe (CustomBooleanOperator (IR.UnpreparedValue 'DataConnector))))
mkCustomOperator tCase collapseIfNull (operatorName, argType) = do
argParser <- mkArgParser argType
pure $
GS.BE.mkBoolOperator tCase collapseIfNull (fromCustomName operatorName) Nothing $
CustomBooleanOperator (GQL.unName operatorName) . Just . Right <$> argParser
mkArgParser :: DC.ScalarType -> GS.C.SchemaT r m (P.Parser 'P.Both n (IR.UnpreparedValue 'DataConnector))
mkArgParser argType =
fmap IR.mkParameter
<$> columnParser'
(RQL.ColumnScalar argType)
(GQL.Nullability True)
tableArgs' ::
forall r m n.
MonadBuildSchema 'DataConnector r m n =>
RQL.TableInfo 'DataConnector ->
GS.C.SchemaT r m (P.InputFieldsParser n (IR.SelectArgsG 'DataConnector (IR.UnpreparedValue 'DataConnector)))
tableArgs' tableInfo = do
whereParser <- GS.S.tableWhereArg tableInfo
orderByParser <- GS.S.tableOrderByArg tableInfo
let mkSelectArgs whereArg orderByArg limitArg offsetArg =
IR.SelectArgs
{ _saWhere = whereArg,
_saOrderBy = orderByArg,
_saLimit = limitArg,
_saOffset = offsetArg,
_saDistinct = Nothing
}
pure $
mkSelectArgs
<$> whereParser
<*> orderByParser
<*> GS.S.tableLimitArg
<*> GS.S.tableOffsetArg
countTypeInput' ::
MonadParse n =>
Maybe (P.Parser 'P.Both n DC.ColumnName) ->
P.InputFieldsParser n (IR.CountDistinct -> DC.CountAggregate)
countTypeInput' = \case
Just columnEnum -> mkCountAggregate <$> P.fieldOptional Name._column Nothing columnEnum
Nothing -> pure $ mkCountAggregate Nothing
where
mkCountAggregate :: Maybe DC.ColumnName -> IR.CountDistinct -> DC.CountAggregate
mkCountAggregate Nothing _ = DC.StarCount
mkCountAggregate (Just column) IR.SelectCountDistinct = DC.ColumnDistinctCount column
mkCountAggregate (Just column) IR.SelectCountNonDistinct = DC.ColumnCount column