graphql-engine/server/src-lib/Hasura/RQL/IR/BoolExp.hs
Auke Booij 3c3ed55914 server: schema that grows (#105)
This PR makes a bunch of schema generation code in Hasura.GraphQL.Schema backend-agnostic, by moving the backend-specific parts into a new BackendSchema type class. This way, the schema generation code can be reused for other backends, simply by implementing new instances of the BackendSchema type class.

This work is now in a state where the schema generators are sufficiently generic to accept the implementation of a new backend. That means that we can start exposing MS SQL schema. Execution is not implemented yet, of course.
The branch currently does not support computed fields or Relay. This is, in a sense, intentional: computed field support is normally baked into the schema generation (through the fieldSelection schema generator), and so this branch shows a programming technique that allows us to expose certain GraphQL schema depending on backend support. We can write support for computed fields and Relay at a later stage.

Co-authored-by: Antoine Leblanc <antoine@hasura.io>
GitOrigin-RevId: df369fc3d189cbda1b931d31678e9450a6601314
2020-12-01 15:51:13 +00:00

443 lines
14 KiB
Haskell

{-# LANGUAGE UndecidableInstances #-}
module Hasura.RQL.IR.BoolExp
( BoolExp(..)
, ColExp(..)
, GBoolExp(..)
, gBoolExpTrue
, gBoolExpToJSON
, parseGBoolExp
, GExists(..)
, geWhere
, geTable
, _BoolExists
, DWithinGeomOp(..)
, DWithinGeogOp(..)
, CastExp
, OpExpG(..)
, opExpDepCol
, STIntersectsNbandGeommin(..)
, STIntersectsGeomminNband(..)
, AnnBoolExpFld(..)
, AnnBoolExp
, traverseAnnBoolExp
, fmapAnnBoolExp
, annBoolExpTrue
, andAnnBoolExps
, AnnBoolExpFldSQL
, AnnBoolExpSQL
, PartialSQLExp(..)
, isStaticValue
, AnnBoolExpFldPartialSQL
, AnnBoolExpPartialSQL
, PreSetColsG
, PreSetColsPartial
) where
import Hasura.Prelude
import qualified Data.Aeson.Types as J
import qualified Data.HashMap.Strict as M
import Control.Lens.Plated
import Control.Lens.TH
import Data.Aeson
import Data.Aeson.Casing
import Data.Aeson.Internal
import Data.Aeson.TH
import Data.Typeable
import Data.Text.Extended
import Hasura.Incremental (Cacheable)
import Hasura.RQL.Types.Column
import Hasura.RQL.Types.Common
import Hasura.SQL.Backend
import Hasura.SQL.Types
import Hasura.Session
data ColExp
= ColExp
{ ceCol :: !FieldName
, ceVal :: !Value
} deriving (Show, Eq, Data, Generic)
instance NFData ColExp
instance Cacheable ColExp
data GExists (b :: BackendType) a
= GExists
{ _geTable :: !(TableName b)
, _geWhere :: !(GBoolExp b a)
} deriving (Functor, Foldable, Traversable, Generic)
deriving instance (Backend b, Show a) => Show (GExists b a)
deriving instance (Backend b, Eq a) => Eq (GExists b a)
deriving instance (Backend b, Typeable a, Data a) => Data (GExists b a)
instance (Backend b, NFData a) => NFData (GExists b a)
instance (Backend b, Data a) => Plated (GExists b a)
instance (Backend b, Cacheable a) => Cacheable (GExists b a)
instance (Backend b, Hashable a) => Hashable (GExists b a)
gExistsToJSON :: (a -> (Text, Value)) -> GExists 'Postgres a -> Value
gExistsToJSON f (GExists qt wh) =
object [ "_table" .= qt
, "_where" .= gBoolExpToJSON f wh
]
parseGExists
:: ((Text, Value) -> J.Parser a) -> Value -> J.Parser (GExists 'Postgres a)
parseGExists f = \case
Object o -> do
qt <- o .: "_table"
wh <- o .: "_where"
GExists qt <$> parseGBoolExp f wh
_ -> fail "expecting an Object for _exists expression"
data GBoolExp (b :: BackendType) a
= BoolAnd ![GBoolExp b a]
| BoolOr ![GBoolExp b a]
| BoolNot !(GBoolExp b a)
| BoolExists !(GExists b a)
| BoolFld !a
deriving (Show, Eq, Functor, Foldable, Traversable, Data, Generic)
instance (Backend b, NFData a) => NFData (GBoolExp b a)
instance (Backend b, Data a) => Plated (GBoolExp b a)
instance (Backend b, Cacheable a) => Cacheable (GBoolExp b a)
instance (Backend b, Hashable a) => Hashable (GBoolExp b a)
gBoolExpTrue :: GBoolExp b a
gBoolExpTrue = BoolAnd []
gBoolExpToJSON :: (a -> (Text, Value)) -> GBoolExp 'Postgres a -> Value
gBoolExpToJSON f be = case be of
-- special encoding for _and
BoolAnd bExps ->
let m = M.fromList $ map getKV bExps
-- if the keys aren't repeated, then object encoding can be used
in if length m == length bExps
then toJSON m
else object $ pure kv
_ -> object $ pure kv
where
kv = getKV be
getKV = \case
BoolAnd bExps -> "_and" .= map (gBoolExpToJSON f) bExps
BoolOr bExps -> "_or" .= map (gBoolExpToJSON f) bExps
BoolNot bExp -> "_not" .= gBoolExpToJSON f bExp
BoolExists bExists -> "_exists" .= gExistsToJSON f bExists
BoolFld a -> f a
parseGBoolExp
:: ((Text, Value) -> J.Parser a) -> Value -> J.Parser (GBoolExp 'Postgres a)
parseGBoolExp f = \case
Object o -> do
boolExps <- forM (M.toList o) $ \(k, v) -> if
| k == "$or" -> BoolOr <$> parseGBoolExpL v <?> Key k
| k == "_or" -> BoolOr <$> parseGBoolExpL v <?> Key k
| k == "$and" -> BoolAnd <$> parseGBoolExpL v <?> Key k
| k == "_and" -> BoolAnd <$> parseGBoolExpL v <?> Key k
| k == "$not" -> BoolNot <$> parseGBoolExp f v <?> Key k
| k == "_not" -> BoolNot <$> parseGBoolExp f v <?> Key k
| k == "$exists" -> BoolExists <$> parseGExists f v <?> Key k
| k == "_exists" -> BoolExists <$> parseGExists f v <?> Key k
| otherwise -> BoolFld <$> f (k, v)
return $ BoolAnd boolExps
_ -> fail "expecting an Object for boolean exp"
where
parseGBoolExpL v =
parseJSON v >>= mapM (parseGBoolExp f)
newtype BoolExp (b :: BackendType)
= BoolExp { unBoolExp :: GBoolExp b ColExp }
deriving (Show, Eq, Generic, NFData, Cacheable)
$(makeWrapped ''BoolExp)
instance ToJSON (BoolExp 'Postgres) where
toJSON (BoolExp gBoolExp) =
gBoolExpToJSON f gBoolExp
where
f (ColExp k v) =
(getFieldNameTxt k, v)
instance FromJSON (BoolExp 'Postgres) where
parseJSON =
fmap BoolExp . parseGBoolExp f
where
f (k, v) = ColExp (FieldName k) <$> parseJSON v
data DWithinGeomOp a =
DWithinGeomOp
{ dwgeomDistance :: !a
, dwgeomFrom :: !a
} deriving (Show, Eq, Functor, Foldable, Traversable, Generic, Data)
instance (NFData a) => NFData (DWithinGeomOp a)
instance (Cacheable a) => Cacheable (DWithinGeomOp a)
instance (Hashable a) => Hashable (DWithinGeomOp a)
$(deriveJSON (aesonDrop 6 snakeCase) ''DWithinGeomOp)
data DWithinGeogOp a =
DWithinGeogOp
{ dwgeogDistance :: !a
, dwgeogFrom :: !a
, dwgeogUseSpheroid :: !a
} deriving (Show, Eq, Functor, Foldable, Traversable, Generic, Data)
instance (NFData a) => NFData (DWithinGeogOp a)
instance (Cacheable a) => Cacheable (DWithinGeogOp a)
instance (Hashable a) => Hashable (DWithinGeogOp a)
$(deriveJSON (aesonDrop 6 snakeCase) ''DWithinGeogOp)
data STIntersectsNbandGeommin a =
STIntersectsNbandGeommin
{ singNband :: !a
, singGeommin :: !a
} deriving (Show, Eq, Functor, Foldable, Traversable, Generic, Data)
instance (NFData a) => NFData (STIntersectsNbandGeommin a)
instance (Cacheable a) => Cacheable (STIntersectsNbandGeommin a)
instance (Hashable a) => Hashable (STIntersectsNbandGeommin a)
$(deriveJSON (aesonDrop 4 snakeCase) ''STIntersectsNbandGeommin)
data STIntersectsGeomminNband a =
STIntersectsGeomminNband
{ signGeommin :: !a
, signNband :: !(Maybe a)
} deriving (Show, Eq, Functor, Foldable, Traversable, Generic, Data)
instance (NFData a) => NFData (STIntersectsGeomminNband a)
instance (Cacheable a) => Cacheable (STIntersectsGeomminNband a)
instance (Hashable a) => Hashable (STIntersectsGeomminNband a)
$(deriveJSON (aesonDrop 4 snakeCase) ''STIntersectsGeomminNband)
type CastExp b a = M.HashMap (ScalarType b) [OpExpG b a]
data OpExpG (b :: BackendType) a
= ACast !(CastExp b a)
| AEQ !Bool !a
| ANE !Bool !a
| AIN !a
| ANIN !a
| AGT !a
| ALT !a
| AGTE !a
| ALTE !a
| ALIKE !a -- LIKE
| ANLIKE !a -- NOT LIKE
| AILIKE (XAILIKE b) !a -- ILIKE, case insensitive
| ANILIKE (XANILIKE b) !a-- NOT ILIKE, case insensitive
| ASIMILAR !a -- similar, regex
| ANSIMILAR !a-- not similar, regex
-- Now that in the RQL code we've started to take a "trees that grow"
-- approach (see PR #6003), we may eventually want to move these
-- recently added constructors, which correspond to newly supported
-- Postgres operators, to the backend-specific extensions of this type.
| AREGEX !a -- match POSIX case sensitive, regex
| AIREGEX !a -- match POSIX case insensitive, regex
| ANREGEX !a -- dont match POSIX case sensitive, regex
| ANIREGEX !a -- dont match POSIX case insensitive, regex
| AContains !a
| AContainedIn !a
| AHasKey !a
| AHasKeysAny !a
| AHasKeysAll !a
| ASTContains !a
| ASTCrosses !a
| ASTDWithinGeom !(DWithinGeomOp a)
| ASTDWithinGeog !(DWithinGeogOp a)
| ASTEquals !a
| ASTIntersects !a
| ASTOverlaps !a
| ASTTouches !a
| ASTWithin !a
| ASTIntersectsRast !a
| ASTIntersectsGeomNband !(STIntersectsGeomminNband a)
| ASTIntersectsNbandGeom !(STIntersectsNbandGeommin a)
| ANISNULL -- IS NULL
| ANISNOTNULL -- IS NOT NULL
| CEQ !(Column b)
| CNE !(Column b)
| CGT !(Column b)
| CLT !(Column b)
| CGTE !(Column b)
| CLTE !(Column b)
deriving (Functor, Foldable, Traversable, Generic)
deriving instance (Backend b, Eq a) => Eq (OpExpG b a)
instance (Backend b, NFData a) => NFData (OpExpG b a)
instance (Backend b, Cacheable a) => Cacheable (OpExpG b a)
instance (Backend b, Hashable a) => Hashable (OpExpG b a)
opExpDepCol :: OpExpG backend a -> Maybe (Column backend)
opExpDepCol = \case
CEQ c -> Just c
CNE c -> Just c
CGT c -> Just c
CLT c -> Just c
CGTE c -> Just c
CLTE c -> Just c
_ -> Nothing
opExpToJPair :: (a -> Value) -> OpExpG 'Postgres a -> (Text, Value)
opExpToJPair f = \case
ACast a -> ("_cast", toJSON $ M.map opExpsToJSON a)
AEQ _ a -> ("_eq", f a)
ANE _ a -> ("_ne", f a)
AIN a -> ("_in", f a)
ANIN a -> ("_nin", f a)
AGT a -> ("_gt", f a)
ALT a -> ("_lt", f a)
AGTE a -> ("_gte", f a)
ALTE a -> ("_lte", f a)
ALIKE a -> ("_like", f a)
ANLIKE a -> ("_nlike", f a)
AILIKE _ a -> ("_ilike", f a)
ANILIKE _ a -> ("_nilike", f a)
ASIMILAR a -> ("_similar", f a)
ANSIMILAR a -> ("_nsimilar", f a)
AREGEX a -> ("_regex", f a)
AIREGEX a -> ("_iregex", f a)
ANREGEX a -> ("_nregex", f a)
ANIREGEX a -> ("_niregex", f a)
AContains a -> ("_contains", f a)
AContainedIn a -> ("_contained_in", f a)
AHasKey a -> ("_has_key", f a)
AHasKeysAny a -> ("_has_keys_any", f a)
AHasKeysAll a -> ("_has_keys_all", f a)
ASTContains a -> ("_st_contains", f a)
ASTCrosses a -> ("_st_crosses", f a)
ASTDWithinGeom o -> ("_st_d_within", toJSON $ f <$> o)
ASTDWithinGeog o -> ("_st_d_within", toJSON $ f <$> o)
ASTEquals a -> ("_st_equals", f a)
ASTIntersects a -> ("_st_intersects", f a)
ASTOverlaps a -> ("_st_overlaps", f a)
ASTTouches a -> ("_st_touches", f a)
ASTWithin a -> ("_st_within", f a)
ASTIntersectsRast a -> ("_st_intersects_rast", f a)
ASTIntersectsNbandGeom a -> ("_st_intersects_nband_geom", toJSON $ f <$> a)
ASTIntersectsGeomNband a -> ("_st_intersects_geom_nband", toJSON $ f <$> a)
ANISNULL -> ("_is_null", toJSON True)
ANISNOTNULL -> ("_is_null", toJSON False)
CEQ a -> ("_ceq", toJSON a)
CNE a -> ("_cne", toJSON a)
CGT a -> ("_cgt", toJSON a)
CLT a -> ("_clt", toJSON a)
CGTE a -> ("_cgte", toJSON a)
CLTE a -> ("_clte", toJSON a)
where
opExpsToJSON = object . map (opExpToJPair f)
data AnnBoolExpFld (b :: BackendType) a
= AVCol !(ColumnInfo b) ![OpExpG b a]
| AVRel !(RelInfo b) !(AnnBoolExp b a)
deriving (Functor, Foldable, Traversable, Generic)
deriving instance (Backend b, Eq (ColumnInfo b), Eq a) => Eq (AnnBoolExpFld b a)
instance (Backend b, NFData (ColumnInfo b), NFData a) => NFData (AnnBoolExpFld b a)
instance (Backend b, Cacheable (ColumnInfo b), Cacheable a) => Cacheable (AnnBoolExpFld b a)
instance (Backend b, Hashable (ColumnInfo b), Hashable a) => Hashable (AnnBoolExpFld b a)
type AnnBoolExp b a
= GBoolExp b (AnnBoolExpFld b a)
traverseAnnBoolExp
:: (Applicative f)
=> (a -> f b)
-> AnnBoolExp backend a
-> f (AnnBoolExp backend b)
traverseAnnBoolExp f =
traverse $ \case
AVCol pgColInfo opExps ->
AVCol pgColInfo <$> traverse (traverse f) opExps
AVRel relInfo annBoolExp ->
AVRel relInfo <$> traverseAnnBoolExp f annBoolExp
fmapAnnBoolExp
:: (a -> b)
-> AnnBoolExp backend a
-> AnnBoolExp backend b
fmapAnnBoolExp f =
runIdentity . traverseAnnBoolExp (pure . f)
annBoolExpTrue :: AnnBoolExp backend a
annBoolExpTrue = gBoolExpTrue
andAnnBoolExps :: AnnBoolExp backend a -> AnnBoolExp backend a -> AnnBoolExp backend a
andAnnBoolExps l r =
BoolAnd [l, r]
type AnnBoolExpFldSQL b = AnnBoolExpFld b (SQLExpression b)
type AnnBoolExpSQL b = AnnBoolExp b (SQLExpression b)
type AnnBoolExpFldPartialSQL b = AnnBoolExpFld b (PartialSQLExp b)
type AnnBoolExpPartialSQL b = AnnBoolExp b (PartialSQLExp b)
type PreSetColsG b v = M.HashMap (Column b) v
type PreSetColsPartial b = M.HashMap (Column b) (PartialSQLExp b)
-- doesn't resolve the session variable
data PartialSQLExp (b :: BackendType)
= PSESessVar !(SessionVarType b) !SessionVariable
| PSESQLExp !(SQLExpression b)
deriving (Generic)
deriving instance Backend b => Eq (PartialSQLExp b)
deriving instance Backend b => Data (PartialSQLExp b)
instance Backend b => NFData (PartialSQLExp b)
instance Backend b => Cacheable (PartialSQLExp b)
instance ToJSON (PartialSQLExp 'Postgres) where
toJSON = \case
PSESessVar colTy sessVar -> toJSON (colTy, sessVar)
PSESQLExp e -> toJSON $ toSQLTxt e
instance ToJSON (AnnBoolExpPartialSQL 'Postgres) where
toJSON = gBoolExpToJSON f
where
f annFld = case annFld of
AVCol pci opExps ->
( toTxt $ pgiColumn pci
, toJSON (pci, map opExpSToJSON opExps)
)
AVRel ri relBoolExp ->
( relNameToTxt $ riName ri
, toJSON (ri, toJSON relBoolExp)
)
opExpSToJSON :: OpExpG 'Postgres (PartialSQLExp 'Postgres) -> Value
opExpSToJSON =
object . pure . opExpToJPair toJSON
isStaticValue :: PartialSQLExp backend -> Bool
isStaticValue = \case
PSESessVar _ _ -> False
PSESQLExp _ -> True
makeLenses ''GExists
makePrisms ''GBoolExp