server: support remote relationship with ID scalar types (#92)

Co-authored-by: Karthikeyan Chinnakonda <karthikeyan@hasura.io>
GITHUB_PR_NUMBER: 6227
GITHUB_PR_URL: https://github.com/hasura/graphql-engine/pull/6227

Co-authored-by: Karthikeyan Chinnakonda <karthikeyan@hasura.io>
GitOrigin-RevId: 666ec37d570e46482e0f27db2c97c9e3f9c1f4d3

CHANGELOG.md

@@ -61,6 +61,7 @@ This release contains the [PDV refactor (#4111)](https://github.com/hasura/graph
 - server: Configurable websocket keep-alive interval. Add `--websocket-keepalive` command-line flag and `HASURA_GRAPHQL_WEBSOCKET_KEEPALIVE` env variable (fix #3539)
 - server: validate remote schema queries (fixes #4143)
 - server: introduce optional custom table name in table configuration to track the table according to the custom name. The `set_table_custom_fields` API has been deprecated, A new API `set_table_customization` has been added to set the configuration. (#3811)
+- server: support joining Int or String scalar types to ID scalar type in remote relationship
 - console: allow user to cascade Postgres dependencies when dropping Postgres objects (close #5109) (#5248)
 - console: mark inconsistent remote schemas in the UI (close #5093) (#5181)
 - console: remove ONLY as default for ALTER TABLE in column alter operations (close #5512) #5706

server/src-lib/Hasura/RQL/DDL/RemoteRelationship/Validate.hs

@@ -42,6 +42,7 @@ data ValidationError
   | UnsupportedMultipleElementLists
   | UnsupportedEnum
   | InvalidGraphQLName !Text
+  | IDTypeJoin !G.Name
 
 errorToText :: ValidationError -> Text
 errorToText = \case
@@ -77,6 +78,8 @@ errorToText = \case
     "enum value is not supported"
   InvalidGraphQLName t ->
     t <<> " is not a valid GraphQL identifier"
+  IDTypeJoin typeName ->
+    "Only ID, Int, uuid or String scalar types can be joined to the ID type, but recieved " <>> typeName
 
 -- | Validate a remote relationship given a context.
 validateRemoteRelationship
@@ -281,10 +284,10 @@ renameNamedType rename =
   G.unsafeMkName . rename . G.unName
 
 -- | Convert a field name to a variable name.
-pgColumnToVariable :: (MonadError ValidationError m) => PGCol -> m G.Name
+pgColumnToVariable :: MonadError ValidationError m => PGCol -> m G.Name
 pgColumnToVariable pgCol =
   let pgColText = getPGColTxt pgCol
-  in maybe (throwError $ InvalidGraphQLName pgColText) pure $ G.mkName pgColText
+  in onNothing (G.mkName pgColText) (throwError $ InvalidGraphQLName pgColText)
 
 -- | Lookup the field in the schema.
 lookupField
@@ -342,17 +345,17 @@ validateType permittedVariables value expectedGType schemaDocument =
           namedType <- columnInfoToNamedType fieldInfo
           isTypeCoercible (mkGraphQLType namedType) expectedGType
     G.VInt {} -> do
-      intScalarGType <- mkGraphQLType <$> mkScalarTy PGInteger
+      intScalarGType <- mkGraphQLType <$> getPGScalarTypeName PGInteger
       isTypeCoercible intScalarGType expectedGType
     G.VFloat {} -> do
-      floatScalarGType <- mkGraphQLType <$> mkScalarTy PGFloat
+      floatScalarGType <- mkGraphQLType <$> getPGScalarTypeName PGFloat
       isTypeCoercible floatScalarGType expectedGType
     G.VBoolean {} -> do
-      boolScalarGType <- mkGraphQLType <$> mkScalarTy PGBoolean
+      boolScalarGType <- mkGraphQLType <$> getPGScalarTypeName PGBoolean
       isTypeCoercible boolScalarGType expectedGType
     G.VNull -> throwError NullNotAllowedHere
     G.VString {} -> do
-      stringScalarGType <- mkGraphQLType <$> mkScalarTy PGText
+      stringScalarGType <- mkGraphQLType <$> getPGScalarTypeName PGText
       isTypeCoercible stringScalarGType expectedGType
     G.VEnum _ -> throwError UnsupportedEnum
     G.VList values -> do
@@ -389,12 +392,6 @@ validateType permittedVariables value expectedGType schemaDocument =
     mkGraphQLType =
       G.TypeNamed (G.Nullability False)
 
-    mkScalarTy scalarType = do
-      eitherScalar <- runExceptT $ mkScalarTypeName scalarType
-      case eitherScalar of
-        Left _  -> throwError $ InvalidGraphQLName $ toSQLTxt scalarType
-        Right s -> pure s
-
 isTypeCoercible
   :: (MonadError ValidationError m)
   => G.GType
@@ -409,7 +406,16 @@ isTypeCoercible actualType expectedType =
   let (actualBaseType, actualNestingLevel) = getBaseTyWithNestedLevelsCount actualType
       (expectedBaseType, expectedNestingLevel) = getBaseTyWithNestedLevelsCount expectedType
   in
-  if | actualBaseType /= expectedBaseType -> raiseValidationError
+  if | expectedBaseType == $$(G.litName "ID") ->
+         bool (throwError $ IDTypeJoin actualBaseType)
+              (pure ())
+              -- Check under `Input Coercion` https://spec.graphql.org/June2018/#sec-ID
+              -- We can also include the `ID` type in the below list but it will be
+              -- extraneous because at the time of writing this, we don't generate
+              -- the `ID` type in the DB schema
+              (G.unName actualBaseType `elem`
+               ["ID", "Int", "String", "bigint", "smallint" , "uuid"])
+     | actualBaseType /= expectedBaseType -> raiseValidationError
        -- we cannot coerce two types with different nesting levels,
        -- for example, we cannot coerce [Int] to [[Int]]
      | (actualNestingLevel == expectedNestingLevel || actualNestingLevel == 0) -> pure ()
@@ -417,6 +423,11 @@ isTypeCoercible actualType expectedType =
      where
        raiseValidationError = throwError $ ExpectedTypeButGot expectedType actualType
 
+getPGScalarTypeName :: MonadError ValidationError m => PGScalarType -> m G.Name
+getPGScalarTypeName scalarType =
+  runExceptT (mkScalarTypeName scalarType) >>=
+    flip onLeft (\ _ -> throwError $ InvalidGraphQLName $ toSQLTxt scalarType)
+
 assertListType :: (MonadError ValidationError m) => G.GType -> m ()
 assertListType actualType =
   unless (G.isListType actualType)
@@ -429,9 +440,5 @@ columnInfoToNamedType
   -> m G.Name
 columnInfoToNamedType pci =
   case pgiType pci of
-    PGColumnScalar scalarType -> do
-      eitherScalar <- runExceptT $ mkScalarTypeName scalarType
-      case eitherScalar of
-        Left _  -> throwError $ InvalidGraphQLName $ toSQLTxt scalarType
-        Right s -> pure s
+    PGColumnScalar scalarType -> getPGScalarTypeName scalarType
     _                         -> throwError UnsupportedEnum

server/tests-py/remote_schemas/nodejs/index.js

@@ -74,12 +74,12 @@ const typeDefs = gql`
   type Query {
     hello: String
     messages(where: MessageWhereInpObj, includes: IncludeInpObj): [Message]
-    user(user_id: Int!): User
-    users(user_ids: [Int]!): [User]
+    user(user_id: ID!): User
+    users(user_ids: [ID]!): [User]
     message(id: Int!) : Message
     communications(id: Int): [Communication]
     search(id: Int!): SearchResult
-    getOccupation(name: String!): Occupation!
+    getOccupation(name: ID!): Occupation!
   }
 `;