Use directive to validate input object fields

[almyy]

I'm trying to create a directive that should, on an input object field, validate an input value at runtime. For example:

input Foo {
    bar: String @notBlank
}

I've tried to follow the same idea as the examples here, but there's no datafetcher to wrap, since we don't have any fieldsContainer or fieldDefinition.

Is this currently possible, and if so, could you point me in the right direction?

[lilianchiassai]

You want to use graphql-java-extended-validation, that is not yet perfectly compatible with graphql-java-kickstart.
You will need to overwrite the Graphql configuration (Cliedeman published an example here https://gist.github.com/cliedeman/21b0c943f6c5138c3a68c070cf1fb847).

You will then run into a few problems I ran into in the last few days (both have workarounds):

• SchemaParser.determineType does not determine input types as GraphQLInputObjectType
• Input Validation

[vojtapol]

Please comment on this issue if the question has not been answered.

[brendamckenne]

An issue is open at
graphql-java/graphql-java-extended-validation#12

actually its an issue with @notblank in that extended validation library