{-# LANGUAGE ApplicativeDo #-} {-# LANGUAGE QuasiQuotes #-} {-# LANGUAGE TemplateHaskellQuotes #-} {-# LANGUAGE ViewPatterns #-} -- | Generate table selection schema both for ordinary Hasura-type and -- relay-type queries. All schema with "relay" or "connection" in the name is -- used exclusively by relay. module Hasura.GraphQL.Schema.Select ( selectTableByPk, selectTableConnection, defaultSelectTable, defaultSelectTableAggregate, defaultTableArgs, defaultTableSelectionSet, defaultLogicalModelArgs, defaultLogicalModelSelectionSet, tableAggregationFields, tableConnectionArgs, tableConnectionSelectionSet, tableWhereArg, tableOrderByArg, tableDistinctArg, tableLimitArg, tableOffsetArg, tablePermissionsInfo, tableSelectionList, logicalModelSelectionList, logicalModelArrayRelationshipField, logicalModelObjectRelationshipField, ) where import Control.Lens hiding (index) import Data.Aeson qualified as J import Data.Aeson.Internal qualified as J import Data.Aeson.Key qualified as K import Data.ByteString.Lazy qualified as BL import Data.Has import Data.HashMap.Strict.Extended qualified as HashMap import Data.HashMap.Strict.InsOrd qualified as InsOrdHashMap import Data.Int (Int64) import Data.List.NonEmpty qualified as NE import Data.Text qualified as T import Data.Text.Casing (GQLNameIdentifier) import Data.Text.Casing qualified as C import Data.Text.Extended import Data.Text.NonEmpty (mkNonEmptyText) import Hasura.Backends.Postgres.SQL.Types qualified as Postgres import Hasura.Base.Error import Hasura.Base.ErrorMessage (toErrorMessage) import Hasura.GraphQL.Parser.Class import Hasura.GraphQL.Parser.Internal.Parser qualified as IP import Hasura.GraphQL.Schema.Backend import Hasura.GraphQL.Schema.BoolExp import Hasura.GraphQL.Schema.Common import Hasura.GraphQL.Schema.OrderBy import Hasura.GraphQL.Schema.Parser ( FieldParser, InputFieldsParser, Kind (..), Parser, ) import Hasura.GraphQL.Schema.Parser qualified as P import Hasura.GraphQL.Schema.Table import Hasura.GraphQL.Schema.Typename import Hasura.LogicalModel.Cache (LogicalModelInfo (..)) import Hasura.LogicalModel.Types ( LogicalModelField (..), LogicalModelName (..), LogicalModelType (..), LogicalModelTypeArray (..), LogicalModelTypeReference (..), LogicalModelTypeScalar (..), ) import Hasura.Name qualified as Name import Hasura.NativeQuery.Cache (NativeQueryInfo (..)) import Hasura.Prelude import Hasura.RQL.IR qualified as IR import Hasura.RQL.IR.BoolExp import Hasura.RQL.IR.Select.Lenses 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.CustomTypes import Hasura.RQL.Types.Metadata.Object import Hasura.RQL.Types.NamingCase import Hasura.RQL.Types.Permission qualified as Permission import Hasura.RQL.Types.Relationships.Local import Hasura.RQL.Types.Relationships.Remote import Hasura.RQL.Types.Roles (RoleName, adminRoleName) import Hasura.RQL.Types.Schema.Options (OptimizePermissionFilters (..)) import Hasura.RQL.Types.Schema.Options qualified as Options import Hasura.RQL.Types.SchemaCache hiding (askTableInfo) import Hasura.RQL.Types.Source import Hasura.RQL.Types.SourceCustomization import Hasura.SQL.AnyBackend qualified as AB import Hasura.Server.Utils (executeJSONPath) import Hasura.Table.Cache import Language.GraphQL.Draft.Syntax qualified as G -------------------------------------------------------------------------------- -- Top-level functions. -- -- Those functions implement parsers for top-level components of the schema, -- such as querying a table or a function. They are typically used to implement -- root fields. -- | Simple table selection. -- -- The field for the table accepts table selection arguments, and -- expects a selection of fields -- -- > table_name(limit: 10) { -- > col1: col1_type -- > col2: col2_type -- > }: [table!]! defaultSelectTable :: forall b r m n. (MonadBuildSchema b r m n, BackendTableSelectSchema b) => -- | table info TableInfo b -> -- | field display name G.Name -> -- | field description, if any Maybe G.Description -> SchemaT r m (Maybe (FieldParser n (SelectExp b))) defaultSelectTable tableInfo fieldName description = runMaybeT do sourceInfo :: SourceInfo b <- asks getter let sourceName = _siName sourceInfo tableName = tableInfoName tableInfo tCase = _rscNamingConvention $ _siCustomization sourceInfo roleName <- retrieve scRole selectPermissions <- hoistMaybe $ tableSelectPermissions roleName tableInfo selectionSetParser <- MaybeT $ tableSelectionList tableInfo lift $ P.memoizeOn 'defaultSelectTable (sourceName, tableName, fieldName) do stringifyNumbers <- retrieve Options.soStringifyNumbers tableArgsParser <- tableArguments tableInfo pure $ P.setFieldParserOrigin (MOSourceObjId sourceName (AB.mkAnyBackend $ SMOTable @b tableName)) $ P.subselection fieldName description tableArgsParser selectionSetParser <&> \(args, fields) -> IR.AnnSelectG { IR._asnFields = fields, IR._asnFrom = IR.FromTable tableName, IR._asnPerm = tablePermissionsInfo selectPermissions, IR._asnArgs = args, IR._asnStrfyNum = stringifyNumbers, IR._asnNamingConvention = Just tCase } -- | Simple table connection selection. -- -- The field for the table accepts table connection selection argument, and -- expects a selection of connection fields -- -- > table_name_connection(first: 1) { -- > pageInfo: { -- > hasNextPage: Boolean! -- > endCursor: String! -- > } -- > edges: { -- > cursor: String! -- > node: { -- > id: ID! -- > col1: col1_type -- > col2: col2_type -- > } -- > } -- > }: table_nameConnection! selectTableConnection :: forall b r m n. ( MonadBuildSchema b r m n, BackendTableSelectSchema b, AggregationPredicatesSchema b ) => -- | table info TableInfo b -> -- | field display name G.Name -> -- | field description, if any Maybe G.Description -> -- | primary key columns PrimaryKeyColumns b -> SchemaT r m (Maybe (FieldParser n (ConnectionSelectExp b))) selectTableConnection tableInfo fieldName description pkeyColumns = runMaybeT do sourceInfo :: SourceInfo b <- asks getter let tableName = tableInfoName tableInfo tCase = _rscNamingConvention $ _siCustomization sourceInfo roleName <- retrieve scRole xRelayInfo <- hoistMaybe $ relayExtension @b selectPermissions <- hoistMaybe $ tableSelectPermissions roleName tableInfo selectionSetParser <- fmap P.nonNullableParser <$> MaybeT $ tableConnectionSelectionSet tableInfo lift $ P.memoizeOn 'selectTableConnection (_siName sourceInfo, tableName, fieldName) do stringifyNumbers <- retrieve Options.soStringifyNumbers selectArgsParser <- tableConnectionArgs pkeyColumns tableInfo pure $ P.subselection fieldName description selectArgsParser selectionSetParser <&> \((args, split, slice), fields) -> IR.ConnectionSelect { IR._csXRelay = xRelayInfo, IR._csPrimaryKeyColumns = pkeyColumns, IR._csSplit = split, IR._csSlice = slice, IR._csSelect = IR.AnnSelectG { IR._asnFields = fields, IR._asnFrom = IR.FromTable tableName, IR._asnPerm = tablePermissionsInfo selectPermissions, IR._asnArgs = args, IR._asnStrfyNum = stringifyNumbers, IR._asnNamingConvention = Just tCase } } -- | Table selection by primary key. -- -- > table_name(id: 42) { -- > col1: col1_type -- > col2: col2_type -- > }: table -- -- Returns Nothing if there's nothing that can be selected with -- current permissions or if there are primary keys the user -- doesn't have select permissions for. selectTableByPk :: forall b r m n. (MonadBuildSchema b r m n, BackendTableSelectSchema b) => -- | table info TableInfo b -> -- | field display name G.Name -> -- | field description, if any Maybe G.Description -> SchemaT r m (Maybe (FieldParser n (SelectExp b))) selectTableByPk tableInfo fieldName description = runMaybeT do sourceInfo :: SourceInfo b <- asks getter let sourceName = _siName sourceInfo tableName = tableInfoName tableInfo tCase = _rscNamingConvention $ _siCustomization sourceInfo roleName <- retrieve scRole selectPermissions <- hoistMaybe $ tableSelectPermissions roleName tableInfo primaryKeys <- hoistMaybe $ fmap _pkColumns . _tciPrimaryKey . _tiCoreInfo $ tableInfo selectionSetParser <- MaybeT $ tableSelectionSet tableInfo guard $ all (\c -> ciColumn c `HashMap.member` spiCols selectPermissions) primaryKeys lift $ P.memoizeOn 'selectTableByPk (sourceName, tableName, fieldName) do stringifyNumbers <- retrieve Options.soStringifyNumbers argsParser <- sequenceA <$> for primaryKeys \columnInfo -> do field <- columnParser (ciType columnInfo) (G.Nullability $ ciIsNullable columnInfo) pure $ BoolField . AVColumn columnInfo . pure . AEQ True . IR.mkParameter <$> P.field (ciName columnInfo) (ciDescription columnInfo) field pure $ P.setFieldParserOrigin (MOSourceObjId sourceName (AB.mkAnyBackend $ SMOTable @b tableName)) $ P.subselection fieldName description argsParser selectionSetParser <&> \(boolExpr, fields) -> let defaultPerms = tablePermissionsInfo selectPermissions -- Do not account permission limit since the result is just a nullable object permissions = defaultPerms {IR._tpLimit = Nothing} whereExpr = Just $ BoolAnd $ toList boolExpr in IR.AnnSelectG { IR._asnFields = fields, IR._asnFrom = IR.FromTable tableName, IR._asnPerm = permissions, IR._asnArgs = IR.noSelectArgs {IR._saWhere = whereExpr}, IR._asnStrfyNum = stringifyNumbers, IR._asnNamingConvention = Just tCase } -- | Table aggregation selection -- -- Parser for an aggregation selection of a table. -- > table_aggregate(limit: 10) { -- > aggregate: table_aggregate_fields -- > nodes: [table!]! -- > } :: table_aggregate! -- -- Returns Nothing if there's nothing that can be selected with -- current permissions. defaultSelectTableAggregate :: forall b r m n. (MonadBuildSchema b r m n, BackendTableSelectSchema b) => -- | table info TableInfo b -> -- | field display name G.Name -> -- | field description, if any Maybe G.Description -> SchemaT r m (Maybe (FieldParser n (AggSelectExp b))) defaultSelectTableAggregate tableInfo fieldName description = runMaybeT $ do sourceInfo :: SourceInfo b <- asks getter let sourceName = _siName sourceInfo tableName = tableInfoName tableInfo customization = _siCustomization sourceInfo tCase = _rscNamingConvention customization mkTypename = runMkTypename $ _rscTypeNames customization roleName <- retrieve scRole selectPermissions <- hoistMaybe $ tableSelectPermissions roleName tableInfo guard $ spiAllowAgg selectPermissions xNodesAgg <- hoistMaybe $ nodesAggExtension @b nodesParser <- MaybeT $ tableSelectionList tableInfo lift $ P.memoizeOn 'defaultSelectTableAggregate (sourceName, tableName, fieldName) do stringifyNumbers <- retrieve Options.soStringifyNumbers tableGQLName <- getTableIdentifierName tableInfo tableArgsParser <- tableArguments tableInfo aggregateParser <- tableAggregationFields tableInfo let selectionName = mkTypename $ applyTypeNameCaseIdentifier tCase $ mkTableAggregateTypeName tableGQLName aggregationParser = P.nonNullableParser $ parsedSelectionsToFields IR.TAFExp <$> P.selectionSet selectionName (Just $ G.Description $ "aggregated selection of " <>> tableName) [ IR.TAFNodes xNodesAgg <$> P.subselection_ Name._nodes Nothing nodesParser, IR.TAFAgg <$> P.subselection_ Name._aggregate Nothing aggregateParser ] pure $ P.setFieldParserOrigin (MOSourceObjId sourceName (AB.mkAnyBackend $ SMOTable @b tableName)) $ P.subselection fieldName description tableArgsParser aggregationParser <&> \(args, fields) -> IR.AnnSelectG { IR._asnFields = fields, IR._asnFrom = IR.FromTable tableName, IR._asnPerm = tablePermissionsInfo selectPermissions, IR._asnArgs = args, IR._asnStrfyNum = stringifyNumbers, IR._asnNamingConvention = Just tCase } {- Note [Selectability of tables] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The GraphQL specification requires that if the type of a selected field is an interface, union, or object, then its subselection set must not be empty (Section 5.3.3). Since we model database tables by GraphQL objects, this means that a table can be selected as a GraphQL field only if it has fields that we can select, such as a column. It is perfectly fine not to allow any selections of any columns of the table in the database. In that case, the table would not be selectable as a field in GraphQL. However, this is not the end of the story. In addition to scalar fields, we support relationships between tables, so that we may have another table B as a selected field of this table A. Then the selectability of A depends on the selectability of B: if we permit selection a column of B, then, as a consequence, we permit selection of the relationship from A to B, and hence we permit selection of A, as there would now be valid GraphQL syntax that selects A. In turn, the selectability of B can depend on the selectability of a further table C, through a relationship from B to C. Now consider the case of a table A, whose columns themselves are not selectable, but which has a relationship with itself. Is A selectable? In fact, if A has no further relationships with other tables, or any computed fields, A is not selectable. But as soon as any leaf field in the transitive closure of tables related to A becomes selectable, A itself becomes selectable. In summary, figuring out the selectability of a table is a mess. In order to avoid doing graph theory, for now, we simply pretend that GraphQL did not have the restriction of only allowing selections of fields of type objects when its subselection is non-empty. In practice, this white lie is somewhat unlikely to cause errors on the client side, for the following reasons: - Introspection of the GraphQL schema is normally provided to aid development of valid GraphQL schemas, and so any errors in the exposed schema can be caught at development time: when a developer is building a GraphQL query using schema introspection, they will eventually find out that the selection they aim to do is not valid GraphQL. Put differently: exposing a given field through introspection is not the same as claiming that there is a valid GraphQL query that selects that field. - We only support tables that have at least one column (since we require primary keys), so that the admin role can select every table anyway. -} -- | Fields of a table -- -- > type table{ -- > # table columns -- > column_1: column1_type -- > . -- > column_n: columnn_type -- > -- > # table relationships -- > object_relationship: remote_table -- > array_relationship: [remote_table!]! -- > -- > # computed fields -- > computed_field: field_type -- > -- > # remote relationships -- > remote_field: field_type -- > } defaultTableSelectionSet :: forall b r m n. ( AggregationPredicatesSchema b, BackendTableSelectSchema b, Eq (AnnBoolExp b (IR.UnpreparedValue b)), MonadBuildSchema b r m n ) => TableInfo b -> SchemaT r m (Maybe (Parser 'Output n (AnnotatedFields b))) defaultTableSelectionSet tableInfo = runMaybeT do sourceInfo :: SourceInfo b <- asks getter let sourceName = _siName sourceInfo tableName = tableInfoName tableInfo tableCoreInfo = _tiCoreInfo tableInfo customization = _siCustomization sourceInfo tCase = _rscNamingConvention customization mkTypename = runMkTypename $ _rscTypeNames customization roleName <- retrieve scRole _selectPermissions <- hoistMaybe $ tableSelectPermissions roleName tableInfo schemaKind <- lift $ retrieve scSchemaKind -- If this check fails, it means we're attempting to build a Relay schema, but -- the current backend b does't support Relay; rather than returning an -- incomplete selection set, we fail early and return 'Nothing'. This check -- must happen first, since we can't memoize a @Maybe Parser@. guard $ isHasuraSchema schemaKind || isJust (relayExtension @b) lift $ P.memoizeOn 'defaultTableSelectionSet (sourceName, tableName) do tableGQLName <- getTableIdentifierName tableInfo let objectTypename = mkTypename $ applyTypeNameCaseIdentifier tCase tableGQLName xRelay = relayExtension @b tableFields = HashMap.elems $ _tciFieldInfoMap tableCoreInfo tablePkeyColumns = _pkColumns <$> _tciPrimaryKey tableCoreInfo pkFields = concatMap toList tablePkeyColumns pkFieldDirective = T.intercalate " " $ map (G.unName . ciName) pkFields -- Adding `@key` directives to type for apollo federation. An example -- of type with key directive: -- type Product @key(fields: "upc sku"){ -- upc: UPC! -- sku: SKU! -- name: String -- } pkDirectives = if isApolloFedV1enabled (_tciApolloFederationConfig tableCoreInfo) && (not . null) pkFields then [(G.Directive Name._key . HashMap.singleton Name._fields . G.VString) pkFieldDirective] else mempty description = G.Description . Postgres.getPGDescription <$> _tciDescription tableCoreInfo fieldParsers <- concat <$> for tableFields (fieldSelection tableName tableInfo) -- We don't check *here* that the subselection set is non-empty, -- even though the GraphQL specification requires that it is (see -- Note [Selectability of tables]). However, the GraphQL parser -- enforces that a selection set, if present, is non-empty; and our -- parser later verifies that a selection set is present if -- required, meaning that not having this check here does not allow -- for the construction of invalid queries. case (schemaKind, tablePkeyColumns, xRelay) of -- A relay table (RelaySchema nodeBuilder, Just pkeyColumns, Just xRelayInfo) -> do let nodeIdFieldParser = P.selection_ Name._id Nothing P.identifier $> IR.AFNodeId xRelayInfo sourceName tableName pkeyColumns allFieldParsers = fieldParsers <> [nodeIdFieldParser] context <- asks getter options <- asks getter -- This `lift` is important! If we don't use it, the underlying node -- builder will assume that the current `SchemaT r m` is the monad in -- which to run, and will stack another `SchemaT` on top of it when -- recursively processing tables. nodeInterface <- lift $ runNodeBuilder nodeBuilder context options pure $ selectionSetObjectWithDirective objectTypename description allFieldParsers [nodeInterface] pkDirectives <&> parsedSelectionsToFields IR.AFExpression _ -> pure $ selectionSetObjectWithDirective objectTypename description fieldParsers [] pkDirectives <&> parsedSelectionsToFields IR.AFExpression where selectionSetObjectWithDirective name description parsers implementsInterfaces directives = IP.setParserDirectives directives $ P.selectionSetObject name description parsers implementsInterfaces -- | List of table fields object. -- Just a @'nonNullableObjectList' wrapper over @'tableSelectionSet'. -- > table_name: [table!]! tableSelectionList :: (MonadBuildSchema b r m n, BackendTableSelectSchema b) => TableInfo b -> SchemaT r m (Maybe (Parser 'Output n (AnnotatedFields b))) tableSelectionList tableInfo = fmap nonNullableObjectList <$> tableSelectionSet tableInfo logicalModelColumnsForRole :: RoleName -> LogicalModelInfo b -> Maybe (Permission.PermColSpec b) logicalModelColumnsForRole role logicalModel = if role == adminRoleName then -- if admin, assume all columns are OK pure Permission.PCStar else -- find list of columns we're allowed to access for this role HashMap.lookup role (_lmiPermissions logicalModel) >>= _permSel <&> Permission.PCCols . HashMap.keys . spiCols -- | this seems like it works on luck, ie that everything is really just Text -- underneath columnToRelName :: forall b. (Backend b) => Column b -> Maybe RelName columnToRelName column = RelName <$> mkNonEmptyText (toTxt column) -- | parse a single logical model field. Currently the only way to 'fulfil' a -- non-scalar field is with a relationship that provides the nested -- object/array information. parseLogicalModelField :: forall b r m n. ( MonadBuildSchema b r m n, BackendNativeQuerySelectSchema b ) => InsOrdHashMap RelName (RelInfo b) -> Column b -> LogicalModelField b -> MaybeT (SchemaT r m) (IP.FieldParser MetadataObjId n (AnnotatedField b)) parseLogicalModelField _ column ( LogicalModelField { lmfDescription, lmfType = LogicalModelTypeScalar (LogicalModelTypeScalarC {lmtsScalar, lmtsNullable}) } ) = do columnName <- hoistMaybe (G.mkName (toTxt column)) -- We have not yet worked out what providing permissions here enables let caseBoolExpUnpreparedValue = Nothing columnType = ColumnScalar lmtsScalar pathArg = scalarSelectionArgumentsParser columnType field <- lift $ columnParser columnType (G.Nullability lmtsNullable) pure $! P.selection columnName (G.Description <$> lmfDescription) pathArg field <&> IR.mkAnnColumnField column columnType caseBoolExpUnpreparedValue parseLogicalModelField relationshipInfo column ( LogicalModelField { lmfType = LogicalModelTypeReference (LogicalModelTypeReferenceC {lmtrReference}) } ) = do -- we currently ignore nullability and assume the field is nullable relName <- hoistMaybe $ columnToRelName @b column -- lookup the reference in the data source relationship <- hoistMaybe $ InsOrdHashMap.lookup relName relationshipInfo logicalModelObjectRelationshipField @b @r @m @n lmtrReference relationship parseLogicalModelField relationshipInfo column ( LogicalModelField { lmfType = LogicalModelTypeArray ( LogicalModelTypeArrayC { lmtaArray = LogicalModelTypeReference (LogicalModelTypeReferenceC {lmtrReference}) } ) } ) = do -- we currently ignore nullability and assume the field is -- non-nullable, as are the contents relName <- hoistMaybe $ columnToRelName @b column -- lookup the reference in the data source relationship <- hoistMaybe $ InsOrdHashMap.lookup relName relationshipInfo logicalModelArrayRelationshipField @b @r @m @n lmtrReference relationship parseLogicalModelField _ _ ( LogicalModelField { lmfType = LogicalModelTypeArray (LogicalModelTypeArrayC {lmtaArray = LogicalModelTypeScalar _}) } ) = throw500 "Arrays of scalar types are not currently implemented" parseLogicalModelField _ _ ( LogicalModelField { lmfType = LogicalModelTypeArray (LogicalModelTypeArrayC {lmtaArray = LogicalModelTypeArray _}) } ) = throw500 "Nested arrays are not currently implemented" defaultLogicalModelSelectionSet :: forall b r m n. ( MonadBuildSchema b r m n, BackendNativeQuerySelectSchema b ) => InsOrdHashMap RelName (RelInfo b) -> LogicalModelInfo b -> SchemaT r m (Maybe (Parser 'Output n (AnnotatedFields b))) defaultLogicalModelSelectionSet relationshipInfo logicalModel = runMaybeT $ do roleName <- retrieve scRole selectableColumns <- hoistMaybe $ logicalModelColumnsForRole roleName logicalModel let isSelectable column = case selectableColumns of Permission.PCStar -> True Permission.PCCols cols -> column `elem` cols let fieldName = getLogicalModelName (_lmiName logicalModel) -- which columns are we allowed to access given permissions? let allowedColumns = filter (isSelectable . fst) (InsOrdHashMap.toList (_lmiFields logicalModel)) parsers <- traverse (uncurry (parseLogicalModelField relationshipInfo)) allowedColumns let description = G.Description <$> _lmiDescription logicalModel -- We entirely ignore Relay for now. implementsInterfaces = mempty pure $ P.selectionSetObject fieldName description parsers implementsInterfaces <&> parsedSelectionsToFields IR.AFExpression logicalModelSelectionList :: (MonadBuildSchema b r m n, BackendLogicalModelSelectSchema b) => InsOrdHashMap RelName (RelInfo b) -> LogicalModelInfo b -> SchemaT r m (Maybe (Parser 'Output n (AnnotatedFields b))) logicalModelSelectionList relationshipInfo logicalModel = fmap nonNullableObjectList <$> logicalModelSelectionSet relationshipInfo logicalModel -- | Converts an output type parser from object_type to [object_type!]! nonNullableObjectList :: Parser 'Output m a -> Parser 'Output m a nonNullableObjectList = P.nonNullableParser . P.multiple . P.nonNullableParser -- | Connection fields of a table -- -- > type tableConnection{ -- > pageInfo: PageInfo! -- > edges: [tableEdge!]! -- > } -- -- > type PageInfo{ -- > startCursor: String! -- > endCursor: String! -- > hasNextPage: Boolean! -- > hasPreviousPage: Boolean! -- > } -- -- > type tableEdge{ -- > cursor: String! -- > node: table! -- > } tableConnectionSelectionSet :: forall b r m n. (MonadBuildSchema b r m n, BackendTableSelectSchema b) => TableInfo b -> SchemaT r m (Maybe (Parser 'Output n (ConnectionFields b))) tableConnectionSelectionSet tableInfo = runMaybeT do sourceInfo :: SourceInfo b <- asks getter let sourceName = _siName sourceInfo tableName = tableInfoName tableInfo customization = _siCustomization sourceInfo tCase = _rscNamingConvention customization mkTypename = runMkTypename $ _rscTypeNames customization roleName <- retrieve scRole tableIdentifierName <- lift $ getTableIdentifierName tableInfo let tableGQLName = applyTypeNameCaseIdentifier tCase tableIdentifierName void $ hoistMaybe $ tableSelectPermissions roleName tableInfo edgesParser <- MaybeT $ tableEdgesSelectionSet mkTypename tableGQLName lift $ P.memoizeOn 'tableConnectionSelectionSet (sourceName, tableName) do let connectionTypeName = mkTypename $ tableGQLName <> Name._Connection pageInfo = P.subselection_ Name._pageInfo Nothing pageInfoSelectionSet <&> IR.ConnectionPageInfo edges = P.subselection_ Name._edges Nothing edgesParser <&> IR.ConnectionEdges connectionDescription = G.Description $ "A Relay connection object on " <>> tableName pure $ P.nonNullableParser $ P.selectionSet connectionTypeName (Just connectionDescription) [pageInfo, edges] <&> parsedSelectionsToFields IR.ConnectionTypename where pageInfoSelectionSet :: Parser 'Output n IR.PageInfoFields pageInfoSelectionSet = let startCursorField = P.selection_ Name._startCursor Nothing P.string $> IR.PageInfoStartCursor endCursorField = P.selection_ Name._endCursor Nothing P.string $> IR.PageInfoEndCursor hasNextPageField = P.selection_ Name._hasNextPage Nothing P.boolean $> IR.PageInfoHasNextPage hasPreviousPageField = P.selection_ Name._hasPreviousPage Nothing P.boolean $> IR.PageInfoHasPreviousPage allFields = [ startCursorField, endCursorField, hasNextPageField, hasPreviousPageField ] in P.nonNullableParser $ P.selectionSet Name._PageInfo Nothing allFields <&> parsedSelectionsToFields IR.PageInfoTypename tableEdgesSelectionSet :: (G.Name -> G.Name) -> G.Name -> SchemaT r m (Maybe (Parser 'Output n (EdgeFields b))) tableEdgesSelectionSet mkTypename tableGQLName = runMaybeT do edgeNodeParser <- MaybeT $ fmap P.nonNullableParser <$> tableSelectionSet tableInfo let edgesType = mkTypename $ tableGQLName <> Name._Edge cursor = P.selection_ Name._cursor Nothing P.string $> IR.EdgeCursor edgeNode = P.subselection_ Name._node Nothing edgeNodeParser <&> IR.EdgeNode pure $ nonNullableObjectList $ P.selectionSet edgesType Nothing [cursor, edgeNode] <&> parsedSelectionsToFields IR.EdgeTypename -------------------------------------------------------------------------------- -- Components -- -- Those parsers are sub-components of those top-level parsers. -- | Arguments for a table selection. Default implementation for BackendSchema. -- -- > distinct_on: [table_select_column!] -- > limit: Int -- > offset: Int -- > order_by: [table_order_by!] -- > where: table_bool_exp defaultTableArgs :: forall b r m n. (MonadBuildSchema b r m n, AggregationPredicatesSchema b) => TableInfo b -> SchemaT r m (InputFieldsParser n (SelectArgs b)) defaultTableArgs tableInfo = do whereParser <- tableWhereArg tableInfo orderByParser <- tableOrderByArg tableInfo distinctParser <- tableDistinctArg tableInfo defaultArgsParser whereParser orderByParser distinctParser -- | Argument to filter rows returned from table selection -- > where: table_bool_exp logicalModelWhereArg :: forall b r m n. ( MonadBuildSchema b r m n, AggregationPredicatesSchema b ) => LogicalModelInfo b -> SchemaT r m (InputFieldsParser n (Maybe (IR.AnnBoolExp b (IR.UnpreparedValue b)))) logicalModelWhereArg logicalModel = do boolExpParser <- logicalModelBoolExp logicalModel pure $ fmap join $ P.fieldOptional whereName whereDesc $ P.nullable boolExpParser where whereName = Name._where whereDesc = Just $ G.Description "filter the rows returned" -- | Argument to sort rows returned from table selection -- > order_by: [table_order_by!] logicalModelOrderByArg :: forall b r m n. ( MonadBuildSchema b r m n ) => LogicalModelInfo b -> SchemaT r m (InputFieldsParser n (Maybe (NonEmpty (IR.AnnotatedOrderByItemG b (IR.UnpreparedValue b))))) logicalModelOrderByArg logicalModel = do tCase <- retrieve $ _rscNamingConvention . _siCustomization @b orderByParser <- logicalModelOrderByExp logicalModel let orderByName = applyFieldNameCaseCust tCase Name._order_by orderByDesc = Just $ G.Description "sort the rows by one or more columns" pure $ do maybeOrderByExps <- fmap join $ P.fieldOptional orderByName orderByDesc $ P.nullable $ P.list orderByParser pure $ maybeOrderByExps >>= NE.nonEmpty . concat -- | Argument to distinct select on columns returned from table selection -- > distinct_on: [table_select_column!] logicalModelDistinctArg :: forall b r m n. ( MonadBuildSchema b r m n ) => LogicalModelInfo b -> SchemaT r m (InputFieldsParser n (Maybe (NonEmpty (Column b)))) logicalModelDistinctArg logicalModel = do let name = getLogicalModelName (_lmiName logicalModel) tCase <- retrieve $ _rscNamingConvention . _siCustomization @b let maybeColumnDefinitions = traverse definitionFromTypeRow (InsOrdHashMap.keys (_lmiFields logicalModel)) >>= NE.nonEmpty case (,) <$> G.mkName "_enum_name" <*> maybeColumnDefinitions of Nothing -> throw500 $ "Error creating an enum name for logical model " <> tshow (_lmiName logicalModel) Just (enum', columnDefinitions) -> do let enumName = name <> enum' description = Nothing columnsEnum = Just $ P.enum @n enumName description columnDefinitions distinctOnName = applyFieldNameCaseCust tCase Name._distinct_on distinctOnDesc = Just $ G.Description "distinct select on columns" pure do maybeDistinctOnColumns <- join . join <$> for columnsEnum (P.fieldOptional distinctOnName distinctOnDesc . P.nullable . P.list) pure $ maybeDistinctOnColumns >>= NE.nonEmpty where definitionFromTypeRow :: Column b -> Maybe (P.Definition P.EnumValueInfo, Column b) definitionFromTypeRow name' = do columnName <- G.mkName (toTxt name') let definition = P.Definition { dName = columnName, dDescription = Just "column name", dOrigin = Nothing, dDirectives = mempty, dInfo = P.EnumValueInfo } pure (definition, name') -- | Argument to filter rows returned from table selection -- > where: table_bool_exp tableWhereArg :: forall b r m n. ( AggregationPredicatesSchema b, MonadBuildSchema b r m n ) => TableInfo b -> SchemaT r m (InputFieldsParser n (Maybe (IR.AnnBoolExp b (IR.UnpreparedValue b)))) tableWhereArg tableInfo = do boolExpParser <- tableBoolExp tableInfo pure $ fmap join $ P.fieldOptional whereName whereDesc $ P.nullable boolExpParser where whereName = Name._where whereDesc = Just $ G.Description "filter the rows returned" -- | Argument to sort rows returned from table selection -- > order_by: [table_order_by!] tableOrderByArg :: forall b r m n. (MonadBuildSchema b r m n) => TableInfo b -> SchemaT r m (InputFieldsParser n (Maybe (NonEmpty (IR.AnnotatedOrderByItemG b (IR.UnpreparedValue b))))) tableOrderByArg tableInfo = do tCase <- retrieve $ _rscNamingConvention . _siCustomization @b orderByParser <- tableOrderByExp tableInfo let orderByName = applyFieldNameCaseCust tCase Name._order_by orderByDesc = Just $ G.Description "sort the rows by one or more columns" pure $ do maybeOrderByExps <- fmap join $ P.fieldOptional orderByName orderByDesc $ P.nullable $ P.list orderByParser pure $ maybeOrderByExps >>= NE.nonEmpty . concat -- | Argument to distinct select on columns returned from table selection -- > distinct_on: [table_select_column!] tableDistinctArg :: forall b r m n. (MonadBuildSchema b r m n) => TableInfo b -> SchemaT r m (InputFieldsParser n (Maybe (NonEmpty (Column b)))) tableDistinctArg tableInfo = do tCase <- retrieve $ _rscNamingConvention . _siCustomization @b columnsEnum <- tableSelectColumnsEnum tableInfo let distinctOnName = applyFieldNameCaseCust tCase Name._distinct_on distinctOnDesc = Just $ G.Description "distinct select on columns" pure do maybeDistinctOnColumns <- join . join <$> for columnsEnum (P.fieldOptional distinctOnName distinctOnDesc . P.nullable . P.list) pure $ maybeDistinctOnColumns >>= NE.nonEmpty -- | Argument to limit rows returned from table selection -- > limit: NonNegativeInt tableLimitArg :: forall n. (MonadParse n) => InputFieldsParser n (Maybe Int) tableLimitArg = fmap (fmap fromIntegral . join) $ P.fieldOptional limitName limitDesc $ P.nullable P.nonNegativeInt where limitName = Name._limit limitDesc = Just $ G.Description "limit the number of rows returned" -- | Argument to skip some rows, in conjunction with order_by -- > offset: BigInt tableOffsetArg :: forall n. (MonadParse n) => InputFieldsParser n (Maybe Int64) tableOffsetArg = fmap join $ P.fieldOptional offsetName offsetDesc $ P.nullable P.bigInt where offsetName = Name._offset offsetDesc = Just $ G.Description "skip the first n rows. Use only with order_by" -- | Arguments for a table connection selection -- -- > distinct_on: [table_select_column!] -- > order_by: [table_order_by!] -- > where: table_bool_exp -- > first: Int -- > last: Int -- > before: String -- > after: String tableConnectionArgs :: forall b r m n. (MonadBuildSchema b r m n, AggregationPredicatesSchema b) => PrimaryKeyColumns b -> TableInfo b -> SchemaT r m ( InputFieldsParser n ( SelectArgs b, Maybe (NonEmpty (IR.ConnectionSplit b (IR.UnpreparedValue b))), Maybe IR.ConnectionSlice ) ) tableConnectionArgs pkeyColumns tableInfo = do whereParser <- tableWhereArg tableInfo orderByParser <- fmap (fmap appendPrimaryKeyOrderBy) <$> tableOrderByArg tableInfo distinctParser <- tableDistinctArg tableInfo let maybeFirst = fmap join $ P.fieldOptional Name._first Nothing $ P.nullable P.nonNegativeInt maybeLast = fmap join $ P.fieldOptional Name._last Nothing $ P.nullable P.nonNegativeInt maybeAfter = fmap join $ P.fieldOptional Name._after Nothing $ P.nullable base64Text maybeBefore = fmap join $ P.fieldOptional Name._before Nothing $ P.nullable base64Text firstAndLast = (,) <$> maybeFirst <*> maybeLast afterBeforeAndOrderBy = (,,) <$> maybeAfter <*> maybeBefore <*> orderByParser pure $ do whereF <- whereParser orderBy <- orderByParser distinct <- distinctParser split <- afterBeforeAndOrderBy `P.bindFields` \(after, before, orderBy') -> do rawSplit <- case (after, before) of (Nothing, Nothing) -> pure Nothing (Just _, Just _) -> parseError "\"after\" and \"before\" are not allowed at once" (Just v, Nothing) -> pure $ Just (IR.CSKAfter, v) (Nothing, Just v) -> pure $ Just (IR.CSKBefore, v) for rawSplit (uncurry (parseConnectionSplit orderBy')) slice <- firstAndLast `P.bindFields` \case (Nothing, Nothing) -> pure Nothing (Just _, Just _) -> parseError "\"first\" and \"last\" are not allowed at once" (Just v, Nothing) -> pure $ Just $ IR.SliceFirst $ fromIntegral v (Nothing, Just v) -> pure $ Just $ IR.SliceLast $ fromIntegral v pure ( IR.SelectArgs whereF orderBy Nothing Nothing distinct, split, slice ) where base64Text = base64Decode <$> P.string appendPrimaryKeyOrderBy :: NonEmpty (IR.AnnotatedOrderByItemG b v) -> NonEmpty (IR.AnnotatedOrderByItemG b v) appendPrimaryKeyOrderBy orderBys@(h NE.:| t) = let orderByColumnNames = orderBys ^.. traverse . to IR.obiColumn . IR._AOCColumn . to ciColumn pkeyOrderBys = flip mapMaybe (toList pkeyColumns) $ \columnInfo -> if ciColumn columnInfo `elem` orderByColumnNames then Nothing else Just $ IR.OrderByItemG Nothing (IR.AOCColumn columnInfo) Nothing in h NE.:| (t <> pkeyOrderBys) parseConnectionSplit :: Maybe (NonEmpty (IR.AnnotatedOrderByItemG b (IR.UnpreparedValue b))) -> IR.ConnectionSplitKind -> BL.ByteString -> n (NonEmpty (IR.ConnectionSplit b (IR.UnpreparedValue b))) parseConnectionSplit maybeOrderBys splitKind cursorSplit = do cursorValue <- J.eitherDecode cursorSplit `onLeft` const throwInvalidCursor case maybeOrderBys of Nothing -> forM (nonEmptySeqToNonEmptyList pkeyColumns) $ \columnInfo -> do let columnJsonPath = [J.Key $ K.fromText $ toTxt $ ciColumn columnInfo] columnType = ciType columnInfo columnValue <- iResultToMaybe (executeJSONPath columnJsonPath cursorValue) `onNothing` throwInvalidCursor pgValue <- liftQErr $ parseScalarValueColumnType columnType columnValue let unresolvedValue = IR.UVParameter IR.Unknown $ ColumnValue columnType pgValue pure $ IR.ConnectionSplit splitKind unresolvedValue $ IR.OrderByItemG Nothing (IR.AOCColumn columnInfo) Nothing Just orderBys -> forM orderBys $ \orderBy -> do let IR.OrderByItemG orderType annObCol nullsOrder = orderBy columnType = getOrderByColumnType annObCol orderByItemValue <- iResultToMaybe (executeJSONPath (map (J.Key . K.fromText) (getPathFromOrderBy annObCol)) cursorValue) `onNothing` throwInvalidCursor pgValue <- liftQErr $ parseScalarValueColumnType columnType orderByItemValue let unresolvedValue = IR.UVParameter IR.Unknown $ ColumnValue columnType pgValue pure $ IR.ConnectionSplit splitKind unresolvedValue $ IR.OrderByItemG orderType annObCol nullsOrder where throwInvalidCursor = parseError "the \"after\" or \"before\" cursor is invalid" liftQErr = either (parseError . toErrorMessage . qeError) pure . runExcept mkAggregateOrderByPath = \case IR.AAOCount -> ["count"] IR.AAOOp t _resultType col -> [t, toTxt $ ciColumn col] getPathFromOrderBy = \case IR.AOCColumn columnInfo -> let pathElement = toTxt $ ciColumn columnInfo in [pathElement] IR.AOCObjectRelation relInfo _ obCol -> let pathElement = relNameToTxt $ riName relInfo in pathElement : getPathFromOrderBy obCol IR.AOCArrayAggregation relInfo _ aggOb -> let fieldName = relNameToTxt (riName relInfo) <> "_aggregate" in fieldName : mkAggregateOrderByPath aggOb IR.AOCComputedField cfob -> let fieldNameText = computedFieldNameToText $ IR._cfobName cfob in case IR._cfobOrderByElement cfob of IR.CFOBEScalar _ -> [fieldNameText] IR.CFOBETableAggregation _ _ aggOb -> (fieldNameText <> "_aggregate") : mkAggregateOrderByPath aggOb getOrderByColumnType = \case IR.AOCColumn columnInfo -> ciType columnInfo IR.AOCObjectRelation _ _ obCol -> getOrderByColumnType obCol IR.AOCArrayAggregation _ _ aggOb -> aggregateOrderByColumnType aggOb IR.AOCComputedField cfob -> case IR._cfobOrderByElement cfob of IR.CFOBEScalar scalarType -> ColumnScalar scalarType IR.CFOBETableAggregation _ _ aggOb -> aggregateOrderByColumnType aggOb where aggregateOrderByColumnType = \case IR.AAOCount -> ColumnScalar (aggregateOrderByCountType @b) IR.AAOOp _ resultType _colInfo -> resultType -- | Aggregation fields -- -- > type table_aggregate_fields{ -- > count(distinct: Boolean, columns: [table_select_column!]): Int! -- > sum: table_sum_fields -- > avg: table_avg_fields -- > stddev: table_stddev_fields -- > stddev_pop: table_stddev_pop_fields -- > variance: table_variance_fields -- > var_pop: table_var_pop_fields -- > max: table_max_fields -- > min: table_min_fields -- > } tableAggregationFields :: forall b r m n. (MonadBuildSchema b r m n) => TableInfo b -> SchemaT r m (Parser 'Output n (IR.AggregateFields b (IR.UnpreparedValue b))) tableAggregationFields tableInfo = do sourceInfo :: SourceInfo b <- asks getter let sourceName = _siName sourceInfo tableName = tableInfoName tableInfo customization = _siCustomization sourceInfo tCase = _rscNamingConvention customization mkTypename = _rscTypeNames customization P.memoizeOn 'tableAggregationFields (sourceName, tableName) do tableGQLName <- getTableIdentifierName tableInfo allColumns <- mapMaybe (^? _SCIScalarColumn) <$> tableSelectColumns tableInfo allComputedFields <- if supportsAggregateComputedFields @b -- See 'supportsAggregateComputedFields' for an explanation then tableSelectComputedFields tableInfo else pure [] let numericColumns = onlyNumCols allColumns numericComputedFields = onlyNumComputedFields allComputedFields comparableColumns = onlyComparableCols allColumns customOperatorsAndColumns = HashMap.toList $ HashMap.mapMaybe (getCustomAggOpsColumns allColumns) $ getCustomAggregateOperators @b (_siConfiguration sourceInfo) description = G.Description $ "aggregate fields of " <>> tableInfoName tableInfo selectName = runMkTypename mkTypename $ applyTypeNameCaseIdentifier tCase $ mkTableAggregateFieldTypeName tableGQLName count <- countField nonCountComputedFieldsMap <- fmap (HashMap.unionsWith (++) . concat) $ sequenceA $ catMaybes [ -- operators on numeric computed fields if null numericComputedFields then Nothing else Just $ for numericAggOperators $ \operator -> do numFields <- mkNumericAggComputedFields tableName operator numericComputedFields pure $ HashMap.singleton operator numFields ] nonCountFieldsMap <- fmap (HashMap.unionsWith (++) . concat) $ sequenceA $ catMaybes [ -- operators on numeric columns if null numericColumns then Nothing else Just $ for numericAggOperators $ \operator -> do numFields <- mkNumericAggFields operator numericColumns pure $ HashMap.singleton operator numFields, -- operators on comparable columns if null comparableColumns then Nothing else Just $ do comparableFields <- traverse mkColumnAggField comparableColumns pure $ comparisonAggOperators & map \operator -> HashMap.singleton operator comparableFields, -- -- custom operators if null customOperatorsAndColumns then Nothing else Just $ for customOperatorsAndColumns \(operator, columnTypes) -> do customFields <- traverse (uncurry mkNullableScalarTypeAggField) (toList columnTypes) pure $ HashMap.singleton (C.fromCustomName operator) customFields ] let nonCountFields = HashMap.mapWithKey ( \operator fields -> parseAggOperator mkTypename operator tCase tableGQLName fields ) (HashMap.unionWith (++) nonCountFieldsMap nonCountComputedFieldsMap) aggregateFields :: [FieldParser n (IR.AggregateField b (IR.UnpreparedValue b))] aggregateFields = count : HashMap.elems nonCountFields pure $ P.selectionSet selectName (Just description) aggregateFields <&> parsedSelectionsToFields IR.AFExp where getCustomAggOpsColumns :: [ColumnInfo b] -> HashMap (ScalarType b) (ScalarType b) -> Maybe (NonEmpty (ColumnInfo b, ScalarType b)) getCustomAggOpsColumns columnInfos typeMap = columnInfos & mapMaybe ( \ci@ColumnInfo {..} -> case ciType of ColumnEnumReference _ -> Nothing ColumnScalar scalarType -> (ci,) <$> HashMap.lookup scalarType typeMap ) & nonEmpty mkNumericAggComputedFields :: TableName b -> GQLNameIdentifier -> [ComputedFieldInfo b] -> SchemaT r m [FieldParser n (IR.SelectionField b (IR.UnpreparedValue b))] mkNumericAggComputedFields tableName _name computedFieldInfos = traverse (mkColumnAggComputedField tableName) computedFieldInfos <&> catMaybes mkColumnAggComputedField :: TableName b -> ComputedFieldInfo b -> SchemaT r m (Maybe (FieldParser n (IR.SelectionField b (IR.UnpreparedValue b)))) mkColumnAggComputedField tableName computedFieldInfo = do let annotatedFieldToSelectionField :: AnnotatedField b -> n (IR.SelectionField b (IR.UnpreparedValue b)) annotatedFieldToSelectionField = \case IR.AFComputedField _ computedFieldName (IR.CFSScalar computedFieldScalarSelect _maybeShouldBeNullified) -> pure $ IR.SFComputedField computedFieldName computedFieldScalarSelect _ -> parseError "Only computed fields that return scalar types are supported" computedField computedFieldInfo tableName tableInfo >>= \case (Just fieldParser) -> (pure . Just) (fieldParser `P.bindField` annotatedFieldToSelectionField) Nothing -> pure Nothing mkNumericAggFields :: GQLNameIdentifier -> [ColumnInfo b] -> SchemaT r m [FieldParser n (IR.SelectionField b (IR.UnpreparedValue b))] mkNumericAggFields name | (C.toSnakeG name) == Name._sum = traverse mkColumnAggField -- Memoize here for more sharing. Note: we can't do `P.memoizeOn 'mkNumericAggFields...` -- due to stage restrictions, so just add a string key: | otherwise = traverse \columnInfo -> P.memoizeOn 'tableAggregationFields ("mkNumericAggFields" :: Text, columnInfo) $ -- CAREFUL!: below must only reference columnInfo else memoization key needs to be adapted pure $! do let !cfcol = IR.SFCol (ciColumn columnInfo) (ciType columnInfo) P.selection_ (ciName columnInfo) (ciDescription columnInfo) (P.nullable P.float) $> cfcol mkColumnAggField :: ColumnInfo b -> SchemaT r m (FieldParser n (IR.SelectionField b (IR.UnpreparedValue b))) mkColumnAggField columnInfo = mkColumnAggField' columnInfo (ciType columnInfo) mkColumnAggField' :: ColumnInfo b -> ColumnType b -> SchemaT r m (FieldParser n (IR.SelectionField b (IR.UnpreparedValue b))) mkColumnAggField' columnInfo resultType = do field <- columnParser resultType (G.Nullability True) pure $ P.selection_ (ciName columnInfo) (ciDescription columnInfo) field $> IR.SFCol (ciColumn columnInfo) (ciType columnInfo) mkNullableScalarTypeAggField :: ColumnInfo b -> ScalarType b -> SchemaT r m (FieldParser n (IR.SelectionField b (IR.UnpreparedValue b))) mkNullableScalarTypeAggField columnInfo resultType = mkColumnAggField' columnInfo (ColumnScalar resultType) countField :: SchemaT r m (FieldParser n (IR.AggregateField b (IR.UnpreparedValue b))) countField = do columnsEnum <- tableSelectColumnsEnum tableInfo let distinctName = Name._distinct args = do distinct <- P.fieldOptional distinctName Nothing P.boolean mkCountType <- countTypeInput @b columnsEnum pure $ mkCountType $ maybe IR.SelectCountNonDistinct -- If "distinct" is "null" or absent, we default to @'SelectCountNonDistinct' (bool IR.SelectCountNonDistinct IR.SelectCountDistinct) distinct pure $ IR.AFCount <$> P.selection Name._count Nothing args P.int parseAggOperator :: MkTypename -> GQLNameIdentifier -> NamingCase -> GQLNameIdentifier -> [FieldParser n (IR.SelectionField b (IR.UnpreparedValue b))] -> FieldParser n (IR.AggregateField b (IR.UnpreparedValue b)) parseAggOperator makeTypename operator tCase tableGQLName columns = let opFieldName = applyFieldNameCaseIdentifier tCase operator opText = G.unName opFieldName setName = runMkTypename makeTypename $ applyTypeNameCaseIdentifier tCase $ mkTableAggOperatorTypeName tableGQLName operator setDesc = Just $ G.Description $ "aggregate " <> opText <> " on columns" subselectionParser = P.selectionSet setName setDesc columns <&> parsedSelectionsToFields IR.SFExp in P.subselection_ opFieldName Nothing subselectionParser <&> IR.AFOp . IR.AggregateOp opText -- | shared implementation between tables and logical models defaultArgsParser :: forall b r m n. ( MonadBuildSchema b r m n ) => InputFieldsParser n (Maybe (AnnBoolExp b (IR.UnpreparedValue b))) -> InputFieldsParser n (Maybe (NonEmpty (IR.AnnotatedOrderByItemG b (IR.UnpreparedValue b)))) -> InputFieldsParser n (Maybe (NonEmpty (Column b))) -> SchemaT r m (InputFieldsParser n (SelectArgs b)) defaultArgsParser whereParser orderByParser distinctParser = do let result = do whereArg <- whereParser orderByArg <- orderByParser limitArg <- tableLimitArg offsetArg <- tableOffsetArg distinctArg <- distinctParser pure $ IR.SelectArgs { IR._saWhere = whereArg, IR._saOrderBy = orderByArg, IR._saLimit = limitArg, IR._saOffset = offsetArg, IR._saDistinct = distinctArg } pure $ result `P.bindFields` \args -> do sequence_ do orderBy <- IR._saOrderBy args distinct <- IR._saDistinct args Just $ validateArgs orderBy distinct pure args where validateArgs orderByCols distinctCols = do let colsLen = length distinctCols initOrderBys = take colsLen $ NE.toList orderByCols initOrdByCols = flip mapMaybe initOrderBys $ \ob -> case IR.obiColumn ob of IR.AOCColumn columnInfo -> Just $ ciColumn columnInfo _ -> Nothing isValid = (colsLen == length initOrdByCols) && all (`elem` initOrdByCols) (toList distinctCols) unless isValid $ parseError "\"distinct_on\" columns must match initial \"order_by\" columns" defaultLogicalModelArgs :: forall b r m n. ( MonadBuildSchema b r m n, AggregationPredicatesSchema b ) => LogicalModelInfo b -> SchemaT r m (InputFieldsParser n (SelectArgs b)) defaultLogicalModelArgs logicalModel = do whereParser <- logicalModelWhereArg logicalModel orderByParser <- logicalModelOrderByArg logicalModel distinctParser <- logicalModelDistinctArg logicalModel defaultArgsParser whereParser orderByParser distinctParser -- | An individual field of a table -- -- > field_name(arg_name: arg_type, ...): field_type fieldSelection :: forall b r m n. ( AggregationPredicatesSchema b, BackendTableSelectSchema b, Eq (AnnBoolExp b (IR.UnpreparedValue b)), MonadBuildSchema b r m n ) => TableName b -> TableInfo b -> FieldInfo b -> SchemaT r m [FieldParser n (AnnotatedField b)] fieldSelection table tableInfo = \case FIColumn (SCIScalarColumn columnInfo) -> maybeToList <$> runMaybeT do roleName <- retrieve scRole schemaKind <- retrieve scSchemaKind let fieldName = ciName columnInfo -- If the field name is 'id' and we're building a schema for the Relay -- API, Node's id field will take precedence; consequently we simply -- ignore the original. guard $ isHasuraSchema schemaKind || fieldName /= Name._id let columnName = ciColumn columnInfo selectPermissions <- hoistMaybe $ tableSelectPermissions roleName tableInfo guard $ columnName `HashMap.member` spiCols selectPermissions let !caseBoolExp = join $ HashMap.lookup columnName (spiCols selectPermissions) !caseBoolExpUnpreparedValue = (fmap . fmap) partialSQLExpToUnpreparedValue <$!> caseBoolExp pathArg = scalarSelectionArgumentsParser $ ciType columnInfo -- In an inherited role, when a column is part of all the select -- permissions which make up the inherited role then the nullability -- of the field is determined by the nullability of the DB column -- otherwise it is marked as nullable explicitly, ignoring the column's -- nullability. We do this because -- in multiple roles we execute an SQL query like: -- -- select -- (case when (P1 or P2) then addr else null end) as addr, -- (case when P2 then phone else null end) as phone -- from employee -- where (P1 or P2) -- -- In the above example, P(n) is a predicate configured for a role -- -- NOTE: https://www.microsoft.com/en-us/research/wp-content/uploads/2016/02/FGALanguageICDE07.pdf -- The above is the paper which talks about the idea of cell-level -- authorization and multiple roles. The paper says that we should only -- allow the case analysis only on nullable columns. nullability = ciIsNullable columnInfo || isJust caseBoolExp field <- lift $ columnParser (ciType columnInfo) (G.Nullability nullability) pure $! P.selection fieldName (ciDescription columnInfo) pathArg field <&> IR.mkAnnColumnField (ciColumn columnInfo) (ciType columnInfo) caseBoolExpUnpreparedValue FIColumn (SCIObjectColumn nestedObjectInfo) -> pure . fmap IR.AFNestedObject <$> nestedObjectFieldParser tableInfo nestedObjectInfo FIColumn (SCIArrayColumn NestedArrayInfo {..}) -> fmap (nestedArrayFieldParser _naiSupportsNestedArrays _naiIsNullable) <$> fieldSelection table tableInfo (FIColumn _naiColumnInfo) FIRelationship relationshipInfo -> concat . maybeToList <$> relationshipField table relationshipInfo FIComputedField computedFieldInfo -> maybeToList <$> computedField computedFieldInfo table tableInfo FIRemoteRelationship remoteFieldInfo -> do schemaKind <- retrieve scSchemaKind case (schemaKind, _rfiRHS remoteFieldInfo) of (RelaySchema _, RFISchema _) -> -- Remote schemas aren't currently supported in Relay, and we therefore -- cannot include remote relationships to them while building a -- Relay-specific schema: attempting to do so would raise an error, as -- 'remoteRelationshipField' would attempt to look into the -- 'SchemaOptions' for information about the targeted schema. pure [] _ -> do RemoteRelationshipParserBuilder remoteRelationshipField <- retrieve scRemoteRelationshipParserBuilder relationshipFields <- fromMaybe [] <$> remoteRelationshipField remoteFieldInfo let lhsFields = _rfiLHS remoteFieldInfo pure $ map (fmap (IR.AFRemote . IR.RemoteRelationshipSelect lhsFields)) relationshipFields where nestedObjectFieldParser :: TableInfo b -> NestedObjectInfo b -> SchemaT r m (FieldParser n (AnnotatedNestedObjectSelect b)) nestedObjectFieldParser TableInfo {..} NestedObjectInfo {..} = do let customObjectTypes = _tciCustomObjectTypes _tiCoreInfo case HashMap.lookup _noiType customObjectTypes of Just objectType -> do parser <- nestedObjectParser _noiSupportsNestedObjects customObjectTypes objectType _noiColumn _noiIsNullable pure $ P.subselection_ _noiName _noiDescription parser _ -> throw500 $ "fieldSelection: object type " <> _noiType <<> " not found" outputParserModifier :: Bool -> IP.Parser origin 'Output m a -> IP.Parser origin 'Output m a outputParserModifier True = P.nullableParser outputParserModifier False = P.nonNullableParser nestedArrayFieldParser :: forall origin m b r v. (Functor m) => XNestedArrays b -> Bool -> IP.FieldParser origin m (IR.AnnFieldG b r v) -> IP.FieldParser origin m (IR.AnnFieldG b r v) nestedArrayFieldParser supportsNestedArrays isNullable = wrapNullable . IP.multipleField . fmap (IR.AFNestedArray @b supportsNestedArrays . IR.ANASSimple) where wrapNullable = if isNullable then IP.nullableField else IP.nonNullableField nestedObjectParser :: forall b r m n. (MonadBuildSchema b r m n) => XNestedObjects b -> HashMap G.Name (TableObjectType b) -> TableObjectType b -> Column b -> Bool -> SchemaT r m (P.Parser 'Output n (AnnotatedNestedObjectSelect b)) nestedObjectParser supportsNestedObjects objectTypes objectType column isNullable = do allFieldParsers <- for (toList $ _totFields objectType) outputFieldParser pure $ outputParserModifier isNullable $ P.selectionSet (_totName objectType) (_totDescription objectType) allFieldParsers <&> IR.AnnNestedObjectSelectG supportsNestedObjects column . parsedSelectionsToFields IR.AFExpression where outputFieldParser :: TableObjectFieldDefinition b -> SchemaT r m (IP.FieldParser MetadataObjId n (IR.AnnFieldG b (IR.RemoteRelationshipField IR.UnpreparedValue) (IR.UnpreparedValue b))) outputFieldParser (TableObjectFieldDefinition column' name description (GraphQLType gType) objectFieldType) = P.memoizeOn 'nestedObjectParser (_totName objectType, name) do let go objectFieldType' = case objectFieldType' of TOFTScalar fieldTypeName scalarType -> wrapScalar scalarType $ customScalarParser fieldTypeName TOFTObject objectName -> do objectType' <- HashMap.lookup objectName objectTypes `onNothing` throw500 ("Custom type " <> objectName <<> " not found") parser <- fmap (IR.AFNestedObject @b) <$> nestedObjectParser supportsNestedObjects objectTypes objectType' column' (G.isNullable gType) pure $ P.subselection_ name description parser TOFTArray supportsNestedArrays nestedFieldType isNullable' -> do nestedArrayFieldParser supportsNestedArrays isNullable' <$> go nestedFieldType go objectFieldType where wrapScalar scalarType parser = pure $ P.wrapFieldParser gType (P.selection_ name description parser) $> IR.mkAnnColumnField column' (ColumnScalar scalarType) Nothing Nothing customScalarParser fieldTypeName = let schemaType = P.TNamed P.NonNullable $ P.Definition fieldTypeName Nothing Nothing [] P.TIScalar in P.Parser { pType = schemaType, pParser = P.valueToJSON (P.toGraphQLType schemaType) } {- Note [Permission filter deduplication] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1. `T` and `U` are tables. 1. `r` is a relationship on `T` to table `U` with the join condition, `T.c = U.d` where `c` and `d` are columns on tables `T` and `U` respectively. 1. `s` is a relationship on `U` to table `T` with the join condition, `U.d = T.c`. 1. `p(T)` and `p(U)` denote the permission filters on table `T` and `U` respectively for some role `R`. Consider the SQL that we generate for this query: ``` query { T { c r { d } } } ``` It would be along these lines: ```sql SELECT * FROM ( SELECT * FROM T WHERE p(T) ) AS T LEFT OUTER JOIN LATERAL ( SELECT * FROM U WHERE T.c = U.d AND p(U) ) AS U ON TRUE ``` The expression `T.c = U.d` is the join condition for relationship `r`. Note that we use lateral joins, so the join condition is not expressed using `ON` but on the where clause of `U`. Now, let's say `p(U)` is of the form `{ s : p(T) }`. ```sql SELECT * FROM ( SELECT * FROM T WHERE p(T) ) AS T LEFT OUTER JOIN LATERAL ( SELECT * FROM U WHERE T.c = U.d AND EXISTS ( SELECT 1 FROM T WHERE U.d = T.c AND p(T) ) ) AS U ON TRUE ``` `p(U)`, i.e, `{ s : p(T) }` got expanded to ```sql EXISTS ( SELECT 1 FROM T WHERE U.d = T.c AND p(T) ) ``` Now, assuming, in the `WHERE` clause for `U`, that `T.c = U.d` holds, then the `EXISTS` clause must evaluate to true. The `EXISTS` clause must evaluate to true because the row from `T` we are joining against is exactly such a row satisfying `p(T)`. In other words, the row obtained from `T` (as the left-hand side of the join) satisfies `p(T)`. -} -- | Field parsers for a table relationship relationshipField :: forall b r m n. ( AggregationPredicatesSchema b, BackendTableSelectSchema b, Eq (AnnBoolExp b (IR.UnpreparedValue b)), MonadBuildSchema b r m n ) => TableName b -> RelInfo b -> SchemaT r m (Maybe [FieldParser n (AnnotatedField b)]) relationshipField table ri = runMaybeT do tCase <- retrieve $ _rscNamingConvention . _siCustomization @b roleName <- retrieve scRole optimizePermissionFilters <- retrieve Options.soOptimizePermissionFilters tableInfo <- lift $ askTableInfo @b table otherTableName <- case riTarget ri of RelTargetNativeQuery _ -> error "relationshipField RelTargetNativeQuery" RelTargetTable tn -> pure tn otherTableInfo <- lift $ askTableInfo otherTableName tablePerms <- hoistMaybe $ tableSelectPermissions roleName tableInfo remotePerms <- hoistMaybe $ tableSelectPermissions roleName otherTableInfo relFieldName <- lift $ textToName $ relNameToTxt $ riName ri -- START black magic to deduplicate permission checks let thisTablePerm = IR._tpFilter $ tablePermissionsInfo tablePerms deduplicatePermissions :: AnnBoolExp b (IR.UnpreparedValue b) -> AnnBoolExp b (IR.UnpreparedValue b) deduplicatePermissions x = case (optimizePermissionFilters, x) of ( OptimizePermissionFilters, BoolAnd [ BoolField ( AVRelationship remoteRI RelationshipFilters { rfTargetTablePermissions, rfFilter } ) ] ) -> -- Here we try to figure out if the "forwards" joining condition -- from `table` to the related table `riRTable ri` is equal to the -- "backwards" joining condition from the related table back to -- `table`. If it is, then we can optimize the row-level permission -- filters by dropping them here. let remoteTableName = case riTarget remoteRI of RelTargetTable tn -> Just tn _ -> Nothing in if (remoteTableName == Just table) && (riMapping remoteRI `HashMap.isInverseOf` riMapping ri) && (thisTablePerm == rfTargetTablePermissions) then rfFilter else x _ -> x deduplicatePermissions' :: SelectExp b -> SelectExp b deduplicatePermissions' expr = let newFilter = deduplicatePermissions (IR._tpFilter (IR._asnPerm expr)) in expr {IR._asnPerm = (IR._asnPerm expr) {IR._tpFilter = newFilter}} -- END black magic to deduplicate permission checks case riType ri of ObjRel -> do let desc = Just $ G.Description "An object relationship" selectionSetParser <- MaybeT $ tableSelectionSet otherTableInfo -- We need to set the correct nullability of our GraphQL field. Manual -- relationships are always nullable, and so are "reverse" object -- relationships, i.e. Hasura relationships that are generated from a -- referenced table to a referencing table. For automatic forward object -- relationships, i.e. the generated relationship from table1 to table2, -- where table1 has a foreign key constraint, we have to do some work. -- -- Specifically, we would like to mark the relationship generated from a -- foreign key constraint from table1 to table2 to be non-nullable if -- Postgres enforces that for each row in table1, a corresponding row in -- table2 exists. From the Postgres manual: -- -- "Normally, a referencing row need not satisfy the foreign key -- constraint if any of its referencing columns are null. If MATCH FULL -- is added to the foreign key declaration, a referencing row escapes -- satisfying the constraint only if all its referencing columns are null -- (so a mix of null and non-null values is guaranteed to fail a MATCH -- FULL constraint)." -- -- https://www.postgresql.org/docs/9.5/ddl-constraints.html#DDL-CONSTRAINTS-FK -- -- Since we don't store MATCH FULL in the RQL representation of the -- database, the closest we can get is to only set the field to be -- non-nullable if _all_ of the columns that reference the foreign table -- are non-nullable. Strictly speaking, we could do slightly better by -- setting the field to be non-nullable also if the foreign key has MATCH -- FULL set, and _any_ of the columns is non-nullable. But we skip doing -- this since, as of writing this, the old code used to make the wrong -- decision about nullability of joint foreign keys entirely, so this is -- probably not a very widely used mode of use. The impact of this -- suboptimality is merely that in introspection some fields might get -- marked nullable which are in fact known to always be non-null. nullable <- case (riIsManual ri, riInsertOrder ri) of -- Automatically generated forward relationship (False, BeforeParent) -> do let columns = HashMap.keys $ riMapping ri fieldInfoMap = _tciFieldInfoMap $ _tiCoreInfo tableInfo findColumn col = HashMap.lookup (fromCol @b col) fieldInfoMap ^? _Just . _FIColumn . _SCIScalarColumn -- Fetch information about the referencing columns of the foreign key -- constraint colInfo <- traverse findColumn columns `onNothing` throw500 "could not find column info in schema cache" pure $ boolToNullable $ any ciIsNullable colInfo -- Manual or reverse relationships are always nullable _ -> pure Nullable pure $ pure $ case nullable of Nullable -> id; NotNullable -> IP.nonNullableField $ P.subselection_ relFieldName desc selectionSetParser <&> \fields -> IR.AFObjectRelation $ IR.AnnRelationSelectG (riName ri) (riMapping ri) $ IR.AnnObjectSelectG fields (IR.FromTable otherTableName) $ deduplicatePermissions $ IR._tpFilter $ tablePermissionsInfo remotePerms ArrRel -> do let arrayRelDesc = Just $ G.Description "An array relationship" otherTableParser <- MaybeT $ selectTable otherTableInfo relFieldName arrayRelDesc let arrayRelField = otherTableParser <&> \selectExp -> IR.AFArrayRelation $ IR.ASSimple $ IR.AnnRelationSelectG (riName ri) (riMapping ri) $ deduplicatePermissions' selectExp relAggFieldName = applyFieldNameCaseCust tCase $ relFieldName <> Name.__aggregate relAggDesc = Just $ G.Description "An aggregate relationship" remoteAggField <- lift $ selectTableAggregate otherTableInfo relAggFieldName relAggDesc remoteConnectionField <- runMaybeT $ do -- Parse array connection field only for relay schema RelaySchema _ <- retrieve scSchemaKind _xRelayInfo <- hoistMaybe $ relayExtension @b pkeyColumns <- MaybeT $ (^? tiCoreInfo . tciPrimaryKey . _Just . pkColumns) <$> pure otherTableInfo let relConnectionName = relFieldName <> Name.__connection relConnectionDesc = Just $ G.Description "An array relationship connection" MaybeT $ lift $ selectTableConnection otherTableInfo relConnectionName relConnectionDesc pkeyColumns pure $ catMaybes [ Just arrayRelField, fmap (IR.AFArrayRelation . IR.ASAggregate . IR.AnnRelationSelectG (riName ri) (riMapping ri)) <$> remoteAggField, fmap (IR.AFArrayRelation . IR.ASConnection . IR.AnnRelationSelectG (riName ri) (riMapping ri)) <$> remoteConnectionField ] tablePermissionsInfo :: (Backend b) => SelPermInfo b -> TablePerms b tablePermissionsInfo selectPermissions = IR.TablePerm { IR._tpFilter = fmap partialSQLExpToUnpreparedValue <$> spiFilter selectPermissions, IR._tpLimit = spiLimit selectPermissions } -- | Field parsers for a logical model object relationship logicalModelObjectRelationshipField :: forall b r m n. ( BackendNativeQuerySelectSchema b, MonadBuildSchema b r m n ) => LogicalModelName -> RelInfo b -> MaybeT (SchemaT r m) (FieldParser n (AnnotatedField b)) logicalModelObjectRelationshipField logicalModelName ri | riType ri == ObjRel = case riTarget ri of RelTargetNativeQuery nativeQueryName -> do nativeQueryInfo <- lift $ askNativeQueryInfo nativeQueryName -- not sure if this the correct way to report mismatches, or if it -- even possible for this to be an issue at this point when (logicalModelName /= _lmiName (_nqiReturns nativeQueryInfo)) ( throw500 $ "Expected object relationship to return " <> toTxt logicalModelName <> " but it returns " <> toTxt (_lmiName (_nqiReturns nativeQueryInfo)) <> "." ) relFieldName <- lift $ textToName $ relNameToTxt $ riName ri let objectRelDesc = Just $ G.Description "An object relationship" nativeQueryParser <- MaybeT $ selectNativeQueryObject nativeQueryInfo relFieldName objectRelDesc pure $ nativeQueryParser <&> \selectExp -> IR.AFObjectRelation (IR.AnnRelationSelectG (riName ri) (riMapping ri) selectExp) RelTargetTable _otherTableName -> do throw500 "Object relationships from logical models to tables are not implemented" logicalModelObjectRelationshipField _ _ = hoistMaybe Nothing -- the target logical model expected an object relationship, but this was an array -- | Field parsers for a logical model relationship logicalModelArrayRelationshipField :: forall b r m n. ( BackendNativeQuerySelectSchema b, MonadBuildSchema b r m n ) => LogicalModelName -> RelInfo b -> MaybeT (SchemaT r m) (FieldParser n (AnnotatedField b)) logicalModelArrayRelationshipField logicalModelName ri | riType ri == ArrRel = case riTarget ri of RelTargetNativeQuery nativeQueryName -> do nativeQueryInfo <- lift $ askNativeQueryInfo nativeQueryName relFieldName <- lift $ textToName $ relNameToTxt $ riName ri -- not sure if this the correct way to report mismatches, or if it -- even possible for this to be an issue at this point when (logicalModelName /= _lmiName (_nqiReturns nativeQueryInfo)) ( throw500 $ "Expected array relationship to return " <> toTxt logicalModelName <> " but it returns " <> toTxt (_lmiName (_nqiReturns nativeQueryInfo)) <> "." ) let objectRelDesc = Just $ G.Description "An array relationship" nativeQueryParser <- MaybeT $ selectNativeQuery nativeQueryInfo relFieldName objectRelDesc pure $ nativeQueryParser <&> \selectExp -> IR.AFArrayRelation $ IR.ASSimple $ IR.AnnRelationSelectG (riName ri) (riMapping ri) selectExp RelTargetTable _otherTableName -> do throw500 "Array relationships from logical models to tables are not implemented" logicalModelArrayRelationshipField _ _ = hoistMaybe Nothing -- the target logical model expected an array relationship, but this was an object