graphql-engine/server/src-lib/Hasura/RQL/DDL/ComputedField.hs
Alexis King e47a8c4b86 incremental metadata: Clean up a few lingering loose ends
- Move MonadBase/MonadBaseControl instances for TxE into pg-client-hs
- Set the -qn2 RTS option by default to limit the parallel GC to 2
  threads
- Remove eventlog instrumentation
- Don’t rebuild the schema cache again after running a query that needs
  it to be rebuilt, since we do that explicitly now.
- Remove some redundant checks, and relocate a couple others.
2020-01-08 17:19:03 -06:00

267 lines
10 KiB
Haskell

{- |
Description: Add/Drop computed fields in metadata
-}
module Hasura.RQL.DDL.ComputedField
( AddComputedField(..)
, ComputedFieldDefinition(..)
, runAddComputedField
, addComputedFieldP2Setup
, addComputedFieldToCatalog
, DropComputedField
, dropComputedFieldFromCatalog
, runDropComputedField
) where
import Hasura.Prelude
import Hasura.EncJSON
import Hasura.Incremental (Cacheable)
import Hasura.RQL.DDL.Deps
import Hasura.RQL.DDL.Permission.Internal
import Hasura.RQL.DDL.Schema.Function (RawFunctionInfo (..), mkFunctionArgs)
import Hasura.RQL.Types
import Hasura.Server.Utils (makeReasonMessage)
import Hasura.SQL.Types
import Data.Aeson
import Data.Aeson.Casing
import Data.Aeson.TH
import Language.Haskell.TH.Syntax (Lift)
import qualified Control.Monad.Validate as MV
import qualified Data.HashSet as S
import qualified Data.Sequence as Seq
import qualified Database.PG.Query as Q
import qualified Language.GraphQL.Draft.Syntax as G
data ComputedFieldDefinition
= ComputedFieldDefinition
{ _cfdFunction :: !QualifiedFunction
, _cfdTableArgument :: !(Maybe FunctionArgName)
} deriving (Show, Eq, Lift, Generic)
instance NFData ComputedFieldDefinition
instance Cacheable ComputedFieldDefinition
$(deriveJSON (aesonDrop 4 snakeCase) ''ComputedFieldDefinition)
data AddComputedField
= AddComputedField
{ _afcTable :: !QualifiedTable
, _afcName :: !ComputedFieldName
, _afcDefinition :: !ComputedFieldDefinition
, _afcComment :: !(Maybe Text)
} deriving (Show, Eq, Lift, Generic)
instance NFData AddComputedField
instance Cacheable AddComputedField
$(deriveJSON (aesonDrop 4 snakeCase) ''AddComputedField)
runAddComputedField :: (MonadTx m, CacheRWM m) => AddComputedField -> m EncJSON
runAddComputedField q = do
withPathK "table" $ askTabInfo (_afcTable q)
addComputedFieldToCatalog q
buildSchemaCacheFor $ MOTableObj (_afcTable q) (MTOComputedField $ _afcName q)
pure successMsg
data ComputedFieldValidateError
= CFVENotValidGraphQLName !ComputedFieldName
| CFVEInvalidTableArgument !InvalidTableArgument
| CFVENotBaseReturnType !PGScalarType
| CFVEReturnTableNotFound !QualifiedTable
| CFVENoInputArguments
| CFVEFunctionVolatile
deriving (Show, Eq)
data InvalidTableArgument
= ITANotFound !FunctionArgName
| ITANotComposite !FunctionTableArgument
| ITANotTable !QualifiedTable !FunctionTableArgument
deriving (Show, Eq)
showError :: QualifiedFunction -> ComputedFieldValidateError -> Text
showError qf = \case
CFVENotValidGraphQLName computedField ->
computedField <<> " is not valid GraphQL name"
CFVEInvalidTableArgument (ITANotFound argName) ->
argName <<> " is not an input argument of " <> qf <<> " function"
CFVEInvalidTableArgument (ITANotComposite functionArg) ->
showFunctionTableArgument functionArg <> " is not COMPOSITE type"
CFVEInvalidTableArgument (ITANotTable ty functionArg) ->
showFunctionTableArgument functionArg <> " of type " <> ty
<<> " is not the table to which the computed field is being added"
CFVENotBaseReturnType scalarType ->
"the function " <> qf <<> " returning type " <> toSQLTxt scalarType
<> " is not a BASE type"
CFVEReturnTableNotFound table ->
"the function " <> qf <<> " returning set of table " <> table
<<> " is not tracked or not found in database"
CFVENoInputArguments ->
"the function " <> qf <<> " has no input arguments"
CFVEFunctionVolatile ->
"the function " <> qf <<> " is of type VOLATILE; cannot be added as a computed field"
where
showFunctionTableArgument = \case
FTAFirst -> "first argument of the function " <>> qf
FTANamed argName _ -> argName <<> " argument of the function " <>> qf
addComputedFieldP2Setup
:: (QErrM m)
=> S.HashSet QualifiedTable
-- ^ the set of all tracked tables
-> QualifiedTable
-> ComputedFieldName
-> ComputedFieldDefinition
-> RawFunctionInfo
-> Maybe Text
-> m ComputedFieldInfo
addComputedFieldP2Setup trackedTables table computedField definition rawFunctionInfo comment =
either (throw400 NotSupported . showErrors) pure =<< MV.runValidateT (mkComputedFieldInfo)
where
inputArgNames = rfiInputArgNames rawFunctionInfo
ComputedFieldDefinition function maybeTableArg = definition
functionReturnType = QualifiedPGType (rfiReturnTypeSchema rawFunctionInfo)
(rfiReturnTypeName rawFunctionInfo)
(rfiReturnTypeType rawFunctionInfo)
computedFieldGraphQLName = G.Name $ computedFieldNameToText computedField
mkComputedFieldInfo :: (MV.MonadValidate [ComputedFieldValidateError] m)
=> m ComputedFieldInfo
mkComputedFieldInfo = do
-- Check if computed field name is a valid GraphQL name
unless (G.isValidName computedFieldGraphQLName) $
MV.dispute $ pure $ CFVENotValidGraphQLName computedField
-- Check if function is VOLATILE
when (rfiFunctionType rawFunctionInfo == FTVOLATILE) $
MV.dispute $ pure CFVEFunctionVolatile
-- Validate and resolve return type
returnType <-
if rfiReturnsTable rawFunctionInfo then do
let returnTable = typeToTable functionReturnType
unless (returnTable `S.member` trackedTables) $ MV.dispute $ pure $
CFVEReturnTableNotFound returnTable
pure $ CFRSetofTable returnTable
else do
let scalarType = _qptName functionReturnType
unless (isBaseType functionReturnType) $ MV.dispute $ pure $
CFVENotBaseReturnType scalarType
pure $ CFRScalar scalarType
-- Validate and resolve table argument
let inputArgs = mkFunctionArgs (rfiDefaultArgs rawFunctionInfo)
(rfiInputArgTypes rawFunctionInfo) inputArgNames
tableArgument <- case maybeTableArg of
Just argName ->
case findWithIndex (maybe False (argName ==) . faName) inputArgs of
Just (tableArg, index) -> do
let functionTableArg = FTANamed argName index
validateTableArgumentType functionTableArg $ faType tableArg
pure functionTableArg
Nothing ->
MV.refute $ pure $ CFVEInvalidTableArgument $ ITANotFound argName
Nothing -> do
case inputArgs of
[] -> MV.dispute $ pure CFVENoInputArguments
(firstArg:_) ->
validateTableArgumentType FTAFirst $ faType firstArg
pure FTAFirst
let inputArgSeq = Seq.fromList $ dropTableArgument tableArgument inputArgs
computedFieldFunction =
ComputedFieldFunction function inputArgSeq tableArgument $
rfiDescription rawFunctionInfo
pure $ ComputedFieldInfo computedField computedFieldFunction returnType comment
validateTableArgumentType :: (MV.MonadValidate [ComputedFieldValidateError] m)
=> FunctionTableArgument
-> QualifiedPGType
-> m ()
validateTableArgumentType tableArg qpt = do
when (_qptType qpt /= PGKindComposite) $
MV.dispute $ pure $ CFVEInvalidTableArgument $ ITANotComposite tableArg
let typeTable = typeToTable qpt
unless (table == typeTable) $
MV.dispute $ pure $ CFVEInvalidTableArgument $ ITANotTable typeTable tableArg
showErrors :: [ComputedFieldValidateError] -> Text
showErrors allErrors =
"the computed field " <> computedField <<> " cannot be added to table "
<> table <<> " " <> reasonMessage
where
reasonMessage = makeReasonMessage allErrors (showError function)
dropTableArgument :: FunctionTableArgument -> [FunctionArg] -> [FunctionArg]
dropTableArgument tableArg inputArgs =
case tableArg of
FTAFirst -> tail inputArgs
FTANamed argName _ ->
filter ((/=) (Just argName) . faName) inputArgs
addComputedFieldToCatalog
:: MonadTx m
=> AddComputedField -> m ()
addComputedFieldToCatalog q =
liftTx $ Q.withQE defaultTxErrorHandler
[Q.sql|
INSERT INTO hdb_catalog.hdb_computed_field
(table_schema, table_name, computed_field_name, definition, comment)
VALUES ($1, $2, $3, $4, $5)
|] (schemaName, tableName, computedField, Q.AltJ definition, comment) True
where
QualifiedObject schemaName tableName = table
AddComputedField table computedField definition comment = q
data DropComputedField
= DropComputedField
{ _dccTable :: !QualifiedTable
, _dccName :: !ComputedFieldName
, _dccCascade :: !Bool
} deriving (Show, Eq, Lift)
$(deriveToJSON (aesonDrop 4 snakeCase) ''DropComputedField)
instance FromJSON DropComputedField where
parseJSON = withObject "Object" $ \o ->
DropComputedField
<$> o .: "table"
<*> o .: "name"
<*> o .:? "cascade" .!= False
runDropComputedField
:: (MonadTx m, CacheRWM m)
=> DropComputedField -> m EncJSON
runDropComputedField (DropComputedField table computedField cascade) = do
-- Validation
fields <- withPathK "table" $ _tciFieldInfoMap <$> askTableCoreInfo table
void $ withPathK "name" $ askComputedFieldInfo fields computedField
-- Dependencies check
sc <- askSchemaCache
let deps = getDependentObjs sc $ SOTableObj table $ TOComputedField computedField
when (not cascade && not (null deps)) $ reportDeps deps
withNewInconsistentObjsCheck do
mapM_ purgeComputedFieldDependency deps
dropComputedFieldFromCatalog table computedField
buildSchemaCache
pure successMsg
where
purgeComputedFieldDependency = \case
SOTableObj qt (TOPerm role permType) | qt == table ->
liftTx $ dropPermFromCatalog qt role permType
d -> throw500 $ "unexpected dependency for computed field "
<> computedField <<> "; " <> reportSchemaObj d
dropComputedFieldFromCatalog
:: MonadTx m
=> QualifiedTable -> ComputedFieldName -> m ()
dropComputedFieldFromCatalog (QualifiedObject schema table) computedField =
liftTx $ Q.withQE defaultTxErrorHandler
[Q.sql|
DELETE FROM hdb_catalog.hdb_computed_field
WHERE table_schema = $1
AND table_name = $2
AND computed_field_name = $3
|] (schema, table, computedField) True