Argument directive [QUESTION]

[carolinebholmes]

I'm new to spring boot and graphql, and I'm trying to write a directive that checks that the argument is within a certain numerical range. I wrote a field directive that does this that's very similar to the example in the documentation but when I try to access the values from the SchemaDirectiveWiringEnvironment the value stored in element is null. Also, when I debug the program, it only hits the breakpoint I set in onArgument once, rather than every time I run a query that should be using it.

Here's the code I have in my range directive class (please ignore all the weird type casting as right now I'm just trying to get something working):

@Override
    public GraphQLArgument onArgument(SchemaDirectiveWiringEnvironment<GraphQLArgument> schemaDirectiveWiringEnv) {

        Double min = (Double) schemaDirectiveWiringEnv.getDirective().getArgument("min").getValue();
        Double max = (Double) schemaDirectiveWiringEnv.getDirective().getArgument("max").getValue();

        GraphQLArgument argument = schemaDirectiveWiringEnv.getElement();

        if (argument.getValue() != null) {
            if (Double.parseDouble( (String) argument.getValue()) < min || Double.parseDouble( (String)argument.getValue()) > max)
                throw new InvalidArgumentException("Argument value is out of range. The range is " + min + " to " + max + ".", argument.getValue().toString());
        }

        return argument.transform(builder -> builder
            .build()
        );

    }

and I use the argument directive in a graphqls file here:

extend type Query {
  # Find all model features associated with an account
  findCardAccountFeaturesByCardAccountId(cardAccountId: String! @range(min: 0.00, max: 1.00)): CardAccountFeatures!
}

Can anyone advise on how to access the argument values properly or provide some resources on writing directives for arguments?

[greenled]

The javadoc says this:

An argument ONLY has a value when its used in a schema definition language (SDL) context as the arguments to SDL directives.  The method should not be called in a query context, but rather the AST / variables map should be used to obtain an arguments value.

I have no idea about how to do the later, but there is an alternative solution. You can use an additional FIELD_DEFINITION directive to lookup the arguments' directives. @bbakerman provided an example here.

[oliemansm]

The documentation is outdated. I've created a sample here for the latest version that works.

[fediazgon]

@oliemansm Sorry for commenting on this closed issue, but the problem I see with this implementation is that, if you have two range directives on two different arguments, this will be triggered a total of 4 times. onField will be called twice and the check will be applied to all arguments. Is there a way of avoiding this?