graphql-engine/server/src-lib/Hasura/RQL/DDL/ComputedField.hs
Rakesh Emmadi 8e88e73a52 server/mssql: add cascade to mssql_run_sql
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## Description
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<!-- Describe the changes from a user's perspective -->
We don't have dependency reporting mechanism for `mssql_run_sql` API i.e when a database object (table, column etc.) is dropped through the API we should raise an exception if any dependencies (relationships, permissions etc.) with the database object exists in the metadata.

This PR addresses the above mentioned problem by
-> Integrating transaction to the API to rollback the SQL query execution if dependencies exists and exception is thrown
-> Accepting `cascade` optional field in the API payload to drop the dependencies, if any
-> Accepting `check_metadata_consistency` optional field to bypass (if value set to `false`) the dependency check

### Related Issues
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<!-- Add the issue number below (e.g. #234) -->
Close #1853

### Solution and Design
<!-- How is this iss -->
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The design/solution follows the `run_sql` API implementation for Postgres backend.

### Steps to test and verify
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- Create author - article tables and track them
- Defined object and array relationships
- Try to drop the article table without cascade or cascade set to `false`
- The server should raise the relationship dependency exists exception

## Changelog

-  `CHANGELOG.md` is updated with user-facing content relevant to this PR.
  If no changelog is required, then add the `no-changelog-required` label.

## Affected components
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-  Server
-  Console
-  CLI
-  Docs
-  Community Content
-  Build System
-  Tests
-  Other (list it)

PR-URL: https://github.com/hasura/graphql-engine-mono/pull/2636
GitOrigin-RevId: 0ab152295394056c4ca6f02923142a1658ad25dc
2021-10-22 14:50:13 +00:00

123 lines
3.9 KiB
Haskell

-- |
-- Description: Add/Drop computed fields in metadata
module Hasura.RQL.DDL.ComputedField
( AddComputedField (..),
ComputedFieldDefinition (..),
runAddComputedField,
DropComputedField,
runDropComputedField,
dropComputedFieldInMetadata,
)
where
import Data.Aeson
import Data.HashMap.Strict.InsOrd qualified as OMap
import Data.Text.Extended
import Hasura.Base.Error
import Hasura.EncJSON
import Hasura.Prelude
import Hasura.RQL.DDL.Permission
import Hasura.RQL.Types
import Hasura.SQL.AnyBackend qualified as AB
data AddComputedField b = AddComputedField
{ _afcSource :: !SourceName,
_afcTable :: !(TableName b),
_afcName :: !ComputedFieldName,
_afcDefinition :: !(ComputedFieldDefinition b),
_afcComment :: !(Maybe Text)
}
deriving stock (Generic)
instance (Backend b) => ToJSON (AddComputedField b) where
toJSON = genericToJSON hasuraJSON
instance (Backend b) => FromJSON (AddComputedField b) where
parseJSON = withObject "AddComputedField" $ \o ->
AddComputedField
<$> o .:? "source" .!= defaultSource
<*> o .: "table"
<*> o .: "name"
<*> o .: "definition"
<*> o .:? "comment"
runAddComputedField ::
forall b m.
(BackendMetadata b, MonadError QErr m, CacheRWM m, MetadataM m) =>
AddComputedField b ->
m EncJSON
runAddComputedField q = do
void $ withPathK "table" $ askTabInfo @b source table
let metadataObj =
MOSourceObjId source $
AB.mkAnyBackend $
SMOTableObj @b table $
MTOComputedField computedFieldName
metadata = ComputedFieldMetadata computedFieldName (_afcDefinition q) (_afcComment q)
buildSchemaCacheFor metadataObj $
MetadataModifier $
tableMetadataSetter source table . tmComputedFields
%~ OMap.insert computedFieldName metadata
pure successMsg
where
source = _afcSource q
table = _afcTable q
computedFieldName = _afcName q
data DropComputedField b = DropComputedField
{ _dccSource :: !SourceName,
_dccTable :: !(TableName b),
_dccName :: !ComputedFieldName,
_dccCascade :: !Bool
}
instance (Backend b) => FromJSON (DropComputedField b) where
parseJSON = withObject "DropComputedField" $ \o ->
DropComputedField
<$> o .:? "source" .!= defaultSource
<*> o .: "table"
<*> o .: "name"
<*> o .:? "cascade" .!= False
runDropComputedField ::
forall b m.
(QErrM m, CacheRWM m, MetadataM m, BackendMetadata b) =>
DropComputedField b ->
m EncJSON
runDropComputedField (DropComputedField source table computedField cascade) = do
-- Validation
fields <- withPathK "table" $ _tciFieldInfoMap <$> askTableCoreInfo @b source table
void $ withPathK "name" $ askComputedFieldInfo fields computedField
-- Dependencies check
sc <- askSchemaCache
let deps =
getDependentObjs sc $
SOSourceObj source $
AB.mkAnyBackend $
SOITableObj @b table $
TOComputedField computedField
when (not cascade && not (null deps)) $ reportDependentObjectsExist deps
withNewInconsistentObjsCheck do
metadataModifiers <- mapM purgeComputedFieldDependency deps
buildSchemaCache $
MetadataModifier $
tableMetadataSetter @b source table
%~ dropComputedFieldInMetadata computedField . foldl' (.) id metadataModifiers
pure successMsg
where
purgeComputedFieldDependency = \case
-- TODO: do a better check of ensuring that the dependency is as expected.
-- i.e, the only allowed dependent objects on a computed fields are permissions
-- on the same table
SOSourceObj _ exists
| Just (SOITableObj _ (TOPerm roleName permType)) <-
AB.unpackAnyBackend @b exists ->
pure $ dropPermissionInMetadata roleName permType
d ->
throw500 $
"unexpected dependency for computed field "
<> computedField <<> "; "
<> reportSchemaObj d