graphql-engine/server/src-lib/Hasura/Backends/BigQuery/Instances/Schema.hs
Antoine Leblanc 8a77386fcf server: IR for DB-DB joins
### Description

This PR adds the required IR for DB to DB joins, based on @paf31 and @0x777 's `feature/db-to-db` branch.

To do so, it also refactors the IR to introduce a new type parameter, `r`, which is used to recursively constructs the `v` parameter of remote QueryDBs. When collecting remote joins, we replace `r` with `Const Void`, indicating at the type level that there cannot be any leftover remote join.

Furthermore, this PR refactors IR.Select for readability, moves some code from IR.Root to IR.Select to avoid having to deal with circular dependencies, and makes it compile by adding `error` in all new cases in the execution pipeline.

The diff doesn't make it clear, but most of Select.hs is actually unchanged. Declarations have just been reordered by topic, in the following order:
- type declarations
- instance declarations
- type aliases
- constructor functions
- traverse functions

https://github.com/hasura/graphql-engine-mono/pull/1580

Co-authored-by: Phil Freeman <630306+paf31@users.noreply.github.com>
GitOrigin-RevId: bbdcb4119cec8bb3fc32f1294f91b8dea0728721
2021-06-17 23:13:05 +00:00

396 lines
17 KiB
Haskell
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

{-# OPTIONS_GHC -fno-warn-orphans #-}
module Hasura.Backends.BigQuery.Instances.Schema () where
import Hasura.Prelude
import qualified Data.Aeson as J
import qualified Data.HashMap.Strict as Map
import qualified Data.List.NonEmpty as NE
import qualified Data.Text as T
import Data.Text.Extended
import qualified Hasura.Backends.BigQuery.Types as BigQuery
import qualified Hasura.GraphQL.Parser as P
import qualified Hasura.GraphQL.Schema.Build as GSB
import qualified Hasura.RQL.IR.Select as IR
import qualified Hasura.RQL.IR.Update as IR
import qualified Language.GraphQL.Draft.Syntax as G
import Hasura.Base.Error
import Hasura.GraphQL.Parser hiding (EnumValueInfo, field)
import Hasura.GraphQL.Parser.Internal.Parser hiding (field)
import Hasura.GraphQL.Parser.Internal.TypeChecking
import Hasura.GraphQL.Schema.Backend
import Hasura.GraphQL.Schema.Common
import Hasura.GraphQL.Schema.Select
import Hasura.RQL.IR
import Hasura.RQL.Types
----------------------------------------------------------------
-- BackendSchema instance
instance BackendSchema 'BigQuery where
-- top level parsers
buildTableQueryFields = GSB.buildTableQueryFields
buildTableRelayQueryFields = bqBuildTableRelayQueryFields
buildTableInsertMutationFields = bqBuildTableInsertMutationFields
buildTableUpdateMutationFields = bqBuildTableUpdateMutationFields
buildTableDeleteMutationFields = bqBuildTableDeleteMutationFields
buildFunctionQueryFields = bqBuildFunctionQueryFields
buildFunctionRelayQueryFields = bqBuildFunctionRelayQueryFields
buildFunctionMutationFields = bqBuildFunctionMutationFields
-- backend extensions
relayExtension = Nothing
nodesAggExtension = Just ()
-- table arguments
tableArguments = bqTableArgs
-- indivdual components
columnParser = bqColumnParser
jsonPathArg = bqJsonPathArg
orderByOperators = bqOrderByOperators
comparisonExps = bqComparisonExps
updateOperators = bqUpdateOperators
mkCountType = bqMkCountType
aggregateOrderByCountType = BigQuery.IntegerScalarType
computedField = bqComputedField
node = bqNode
-- SQL literals
columnDefaultValue = error "TODO: Make impossible by the type system. BigQuery doesn't support insertions."
----------------------------------------------------------------
-- Top level parsers
bqBuildTableRelayQueryFields
:: MonadBuildSchema 'BigQuery r m n
=> SourceName
-> SourceConfig 'BigQuery
-> TableName 'BigQuery
-> TableInfo 'BigQuery
-> G.Name
-> NESeq (ColumnInfo 'BigQuery)
-> SelPermInfo 'BigQuery
-> m [FieldParser n (QueryRootField UnpreparedValue UnpreparedValue)]
bqBuildTableRelayQueryFields _sourceName _sourceInfo _tableName _tableInfo _gqlName _pkeyColumns _selPerms =
pure []
bqBuildTableInsertMutationFields
:: MonadBuildSchema 'BigQuery r m n
=> SourceName
-> SourceConfig 'BigQuery
-> TableName 'BigQuery
-> TableInfo 'BigQuery
-> G.Name
-> InsPermInfo 'BigQuery
-> Maybe (SelPermInfo 'BigQuery)
-> Maybe (UpdPermInfo 'BigQuery)
-> m [FieldParser n (MutationRootField UnpreparedValue UnpreparedValue)]
bqBuildTableInsertMutationFields _sourceName _sourceInfo _tableName _tableInfo _gqlName _insPerms _selPerms _updPerms =
pure []
bqBuildTableUpdateMutationFields
:: MonadBuildSchema 'BigQuery r m n
=> SourceName
-> SourceConfig 'BigQuery
-> TableName 'BigQuery
-> TableInfo 'BigQuery
-> G.Name
-> UpdPermInfo 'BigQuery
-> Maybe (SelPermInfo 'BigQuery)
-> m [FieldParser n (MutationRootField UnpreparedValue UnpreparedValue)]
bqBuildTableUpdateMutationFields _sourceName _sourceInfo _tableName _tableInfo _gqlName _updPerns _selPerms =
pure []
bqBuildTableDeleteMutationFields
:: MonadBuildSchema 'BigQuery r m n
=> SourceName
-> SourceConfig 'BigQuery
-> TableName 'BigQuery
-> TableInfo 'BigQuery
-> G.Name
-> DelPermInfo 'BigQuery
-> Maybe (SelPermInfo 'BigQuery)
-> m [FieldParser n (MutationRootField UnpreparedValue UnpreparedValue)]
bqBuildTableDeleteMutationFields _sourceName _sourceInfo _tableName _tableInfo _gqlName _delPerns _selPerms =
pure []
bqBuildFunctionQueryFields
:: MonadBuildSchema 'BigQuery r m n
=> SourceName
-> SourceConfig 'BigQuery
-> FunctionName 'BigQuery
-> FunctionInfo 'BigQuery
-> TableName 'BigQuery
-> SelPermInfo 'BigQuery
-> m [FieldParser n (QueryRootField UnpreparedValue UnpreparedValue)]
bqBuildFunctionQueryFields _ _ _ _ _ _ =
pure []
bqBuildFunctionRelayQueryFields
:: MonadBuildSchema 'BigQuery r m n
=> SourceName
-> SourceConfig 'BigQuery
-> FunctionName 'BigQuery
-> FunctionInfo 'BigQuery
-> TableName 'BigQuery
-> NESeq (ColumnInfo 'BigQuery)
-> SelPermInfo 'BigQuery
-> m [FieldParser n (QueryRootField UnpreparedValue UnpreparedValue)]
bqBuildFunctionRelayQueryFields _sourceName _sourceInfo _functionName _functionInfo _tableName _pkeyColumns _selPerms =
pure []
bqBuildFunctionMutationFields
:: MonadBuildSchema 'BigQuery r m n
=> SourceName
-> SourceConfig 'BigQuery
-> FunctionName 'BigQuery
-> FunctionInfo 'BigQuery
-> TableName 'BigQuery
-> SelPermInfo 'BigQuery
-> m [FieldParser n (MutationRootField UnpreparedValue UnpreparedValue)]
bqBuildFunctionMutationFields _ _ _ _ _ _ =
pure []
----------------------------------------------------------------
-- Table arguments
bqTableArgs
:: forall r m n
. MonadBuildSchema 'BigQuery r m n
=> SourceName
-> TableInfo 'BigQuery
-> SelPermInfo 'BigQuery
-> m (InputFieldsParser n (IR.SelectArgsG 'BigQuery (UnpreparedValue 'BigQuery)))
bqTableArgs sourceName tableInfo selectPermissions = do
whereParser <- tableWhereArg sourceName tableInfo selectPermissions
orderByParser <- tableOrderByArg sourceName tableInfo selectPermissions
pure do
whereArg <- whereParser
orderByArg <- orderByParser
limitArg <- tableLimitArg
offsetArg <- tableOffsetArg
pure $ IR.SelectArgs
{ IR._saWhere = whereArg
, IR._saOrderBy = orderByArg
, IR._saLimit = limitArg
, IR._saOffset = offsetArg
-- not supported on BigQuery for now
, IR._saDistinct = Nothing
}
----------------------------------------------------------------
-- Individual components
bqColumnParser
:: (MonadSchema n m, MonadError QErr m)
=> ColumnType 'BigQuery
-> G.Nullability
-> m (Parser 'Both n (Opaque (ColumnValue 'BigQuery)))
bqColumnParser columnType (G.Nullability isNullable) =
opaque . fmap (ColumnValue columnType) <$> case columnType of
ColumnScalar scalarType -> case scalarType of
-- bytestrings
-- we only accept string literals
BigQuery.BytesScalarType -> pure $ possiblyNullable scalarType $ BigQuery.StringValue <$> P.string
-- text
BigQuery.StringScalarType -> pure $ possiblyNullable scalarType $ BigQuery.StringValue <$> P.string
-- floating point values
-- TODO: we do not perform size checks here, meaning we would accept an
-- out-of-bounds value as long as it can be represented by a GraphQL float; this
-- will in all likelihood error on the BigQuery side. Do we want to handle those
-- properly here?
BigQuery.FloatScalarType -> pure $ possiblyNullable scalarType $ BigQuery.FloatValue . BigQuery.doubleToFloat64 <$> P.float
BigQuery.IntegerScalarType -> pure $ possiblyNullable scalarType $ BigQuery.IntegerValue . BigQuery.intToInt64 . fromIntegral <$> P.int
BigQuery.DecimalScalarType -> pure $ possiblyNullable scalarType $ BigQuery.DecimalValue . BigQuery.doubleToDecimal <$> P.float
BigQuery.BigDecimalScalarType -> pure $ possiblyNullable scalarType $ BigQuery.BigDecimalValue . BigQuery.doubleToBigDecimal <$> P.float
-- boolean type
BigQuery.BoolScalarType -> pure $ possiblyNullable scalarType $ BigQuery.BoolValue <$> P.boolean
BigQuery.DateScalarType -> pure $ possiblyNullable scalarType $ BigQuery.DateValue . BigQuery.Date <$> P.string
BigQuery.TimeScalarType -> pure $ possiblyNullable scalarType $ BigQuery.TimeValue . BigQuery.Time <$> P.string
BigQuery.DatetimeScalarType -> pure $ possiblyNullable scalarType $ BigQuery.DatetimeValue . BigQuery.Datetime <$> P.string
BigQuery.GeographyScalarType -> pure $ possiblyNullable scalarType $ BigQuery.GeographyValue . BigQuery.Geography <$> P.string
BigQuery.TimestampScalarType -> do
let schemaType = P.Nullable . P.TNamed $ P.mkDefinition stringScalar Nothing P.TIScalar
pure $ possiblyNullable scalarType $ Parser
{ pType = schemaType
, pParser =
valueToJSON (P.toGraphQLType schemaType)
>=> fmap (BigQuery.StringValue . BigQuery.utctimeToISO8601Text)
. either (parseErrorWith ParseFailed . qeError) pure
. runAesonParser (J.withText "TimestampColumn" BigQuery.textToUTCTime)
}
ty -> throwError $ internalError $ T.pack $ "Type currently unsupported for BigQuery: " ++ show ty
ColumnEnumReference (EnumReference tableName enumValues) ->
case nonEmpty (Map.toList enumValues) of
Just enumValuesList -> do
tableGQLName <- tableGraphQLName @'BigQuery tableName `onLeft` throwError
let enumName = tableGQLName <> $$(G.litName "_enum")
pure $ possiblyNullable BigQuery.StringScalarType $ P.enum enumName Nothing (mkEnumValue <$> enumValuesList)
Nothing -> throw400 ValidationFailed "empty enum values"
where
-- Sadly, this combinator is not sound in general, so we cant export it
-- for general-purpose use. If we did, someone could write this:
--
-- mkParameter <$> opaque do
-- n <- int
-- pure (mkIntColumnValue (n + 1))
--
-- Now wed end up with a UVParameter that has a variable in it, so wed
-- parameterize over it. But when wed reuse the plan, we wouldnt know to
-- increment the value by 1, so wed use the wrong value!
--
-- We could theoretically solve this by retaining a reference to the parser
-- itself and re-parsing each new value, using the saved parser, which
-- would admittedly be neat. But its more complicated, and it isnt clear
-- that it would actually be useful, so for now we dont support it.
opaque :: MonadParse m => Parser 'Both m a -> Parser 'Both m (Opaque a)
opaque parser = parser
{ pParser = \case
P.GraphQLValue (G.VVariable var@Variable{ vInfo, vValue }) -> do
typeCheck False (P.toGraphQLType $ pType parser) var
P.mkOpaque (Just vInfo) <$> pParser parser (absurd <$> vValue)
value -> P.mkOpaque Nothing <$> pParser parser value
}
possiblyNullable _scalarType
| isNullable = fmap (fromMaybe BigQuery.NullValue) . P.nullable
| otherwise = id
mkEnumValue :: (EnumValue, EnumValueInfo) -> (P.Definition P.EnumValueInfo, ScalarValue 'BigQuery)
mkEnumValue (EnumValue value, EnumValueInfo description) =
( P.mkDefinition value (G.Description <$> description) P.EnumValueInfo
, BigQuery.StringValue $ G.unName value
)
throughJSON scalarName =
let schemaType = P.NonNullable $ P.TNamed $ P.mkDefinition scalarName Nothing P.TIScalar
in Parser
{ pType = schemaType
, pParser =
valueToJSON (P.toGraphQLType schemaType) >=>
either (parseErrorWith ParseFailed . qeError) pure . runAesonParser J.parseJSON
}
bqJsonPathArg
:: MonadParse n
=> ColumnType 'BigQuery
-> InputFieldsParser n (Maybe (IR.ColumnOp 'BigQuery))
bqJsonPathArg _columnType = pure Nothing
bqOrderByOperators
:: NonEmpty
( Definition P.EnumValueInfo
, (BasicOrderType 'BigQuery, NullsOrderType 'BigQuery)
)
bqOrderByOperators = NE.fromList
[ ( define $$(G.litName "asc") "in ascending order, nulls first"
, (BigQuery.AscOrder, BigQuery.NullsFirst)
)
, ( define $$(G.litName "asc_nulls_first") "in ascending order, nulls first"
, (BigQuery.AscOrder, BigQuery.NullsFirst)
)
, ( define $$(G.litName "asc_nulls_last") "in ascending order, nulls last"
, (BigQuery.AscOrder, BigQuery.NullsLast)
)
, ( define $$(G.litName "desc") "in descending order, nulls last"
, (BigQuery.DescOrder, BigQuery.NullsLast)
)
, ( define $$(G.litName "desc_nulls_first") "in descending order, nulls first"
, (BigQuery.DescOrder, BigQuery.NullsFirst)
)
, ( define $$(G.litName "desc_nulls_last") "in descending order, nulls last"
, (BigQuery.DescOrder, BigQuery.NullsLast)
)
]
where
define name desc = P.mkDefinition name (Just desc) P.EnumValueInfo
bqComparisonExps
:: forall m n
. (BackendSchema 'BigQuery, MonadSchema n m, MonadError QErr m)
=> ColumnType 'BigQuery
-> m (Parser 'Input n [ComparisonExp 'BigQuery])
bqComparisonExps = P.memoize 'comparisonExps $ \columnType -> do
-- see Note [Columns in comparison expression are never nullable]
typedParser <- columnParser columnType (G.Nullability False)
nullableTextParser <- columnParser (ColumnScalar @'BigQuery BigQuery.StringScalarType) (G.Nullability True)
textParser <- columnParser (ColumnScalar @'BigQuery BigQuery.StringScalarType) (G.Nullability False)
let name = P.getName typedParser <> $$(G.litName "_BigQuery_comparison_exp")
desc = G.Description $ "Boolean expression to compare columns of type "
<> P.getName typedParser
<<> ". All fields are combined with logical 'AND'."
textListParser = P.list textParser `P.bind` traverse P.openOpaque
columnListParser = P.list typedParser `P.bind` traverse P.openOpaque
pure $ P.object name (Just desc) $ catMaybes <$> sequenceA
[ P.fieldOptional $$(G.litName "_is_null") Nothing (bool ANISNOTNULL ANISNULL <$> P.boolean)
, P.fieldOptional $$(G.litName "_eq") Nothing (AEQ True . mkParameter <$> typedParser)
, P.fieldOptional $$(G.litName "_neq") Nothing (ANE True . mkParameter <$> typedParser)
, P.fieldOptional $$(G.litName "_gt") Nothing (AGT . mkParameter <$> typedParser)
, P.fieldOptional $$(G.litName "_lt") Nothing (ALT . mkParameter <$> typedParser)
, P.fieldOptional $$(G.litName "_gte") Nothing (AGTE . mkParameter <$> typedParser)
, P.fieldOptional $$(G.litName "_lte") Nothing (ALTE . mkParameter <$> typedParser)
]
bqMkCountType
:: Maybe Bool
-- ^ distinct values
-> Maybe [Column 'BigQuery]
-> CountType 'BigQuery
bqMkCountType _ Nothing = BigQuery.StarCountable
bqMkCountType (Just True) (Just cols) =
maybe BigQuery.StarCountable BigQuery.DistinctCountable $ nonEmpty cols
bqMkCountType _ (Just cols) =
maybe BigQuery.StarCountable BigQuery.NonNullFieldCountable $ nonEmpty cols
-- | Various update operators
bqUpdateOperators
-- :: forall m n r. (MonadSchema n m, MonadTableInfo r m)
:: Applicative m
=> TableInfo 'BigQuery -- ^ qualified name of the table
-> UpdPermInfo 'BigQuery -- ^ update permissions of the table
-> m (Maybe (InputFieldsParser n [(Column 'BigQuery, IR.UpdOpExpG (UnpreparedValue 'BigQuery))]))
bqUpdateOperators _tableInfo _updatePermissions = pure Nothing
-- | Computed field parser.
-- Currently unsupported: returns Nothing for now.
bqComputedField
:: MonadBuildSchema 'BigQuery r m n
=> SourceName
-> ComputedFieldInfo 'BigQuery
-> TableName 'BigQuery
-> SelPermInfo 'BigQuery
-> m (Maybe (FieldParser n (AnnotatedField 'BigQuery)))
bqComputedField _sourceName _fieldInfo _table _selectPemissions = pure Nothing
-- | Remote join field parser.
-- Currently unsupported: returns Nothing for now.
bqRemoteRelationshipField
:: MonadBuildSchema 'BigQuery r m n
=> RemoteFieldInfo 'BigQuery
-> m (Maybe [FieldParser n (AnnotatedField 'BigQuery)])
bqRemoteRelationshipField _remoteFieldInfo = pure Nothing
-- | The 'node' root field of a Relay request. Relay is currently unsupported on BigQuery,
-- meaning this parser will never be called: any attempt to create this parser should
-- therefore fail.
bqNode
:: MonadBuildSchema 'BigQuery r m n
=> m ( Parser 'Output n
( HashMap
( TableName 'BigQuery)
( SourceName, SourceConfig 'BigQuery
, SelPermInfo 'BigQuery
, PrimaryKeyColumns 'BigQuery
, AnnotatedFields 'BigQuery
)
)
)
bqNode = throw500 "BigQuery does not support relay; `node` should never be exposed in the schema."