DefaultErrorHandler returning "Internal Server Error(s)" for some GraphQLErrors caused by clients

[kagof]

Our graph returns an "Internal Server Error(s) while executing query" error when a graphql.execution.NonNullableValueCoercedAsNullException or graphql.execution.InputMapDefinesTooManyFieldsException is thrown. Both of these error are core GraphQL-Java client errors caused by bad user data. I'm sure a few other errors also may be in this situation, but these are the only ones I've encountered so far.

I believe the issue lies with DefaultGraphQLErrorHandler::isClientError(GraphQLError). If the error is not an ExceptionWhileDataFetching (which these are not, since they occur before data fetching happens), then it just returns !(error instanceof Throwable). Since both of these errors are Throwables, they are not recognized as client errors. I'm not sure what the reasoning is behind this check so I may be missing something here, but it seems to me that it should be checking something else.

graphql-java version: 11.0
graphql-java-servlet version: 7.3.0

[oliemansm]

Looks like this check was added as a temporary fix because of a bug in graphql-java 3.0.0, and was never reverted. I'll revert it now for 7.5.1. See also #37