graphql-yoga/esm/validations/defer-stream-directive-label.js

import { GraphQLError, Kind } from 'graphql';
import { GraphQLDeferDirective } from '../directives/defer.js';
import { GraphQLStreamDirective } from '../directives/stream.js';
/**
 * Stream directive on list field
 *
 * A GraphQL document is only valid if defer and stream directives' label argument is static and unique.
 */
export function DeferStreamDirectiveLabelRule(context) {
    const knownLabels = Object.create(null);
    return {
        Directive(node) {
            if (node.name.value === GraphQLDeferDirective.name ||
                node.name.value === GraphQLStreamDirective.name) {
                const labelArgument = node.arguments?.find((arg) => arg.name.value === 'label');
                const labelValue = labelArgument?.value;
                if (!labelValue) {
                    return;
                }
                if (labelValue.kind !== Kind.STRING) {
                    context.reportError(new GraphQLError(`Directive "${node.name.value}"'s label argument must be a static string.`, { nodes: node }));
                }
                else if (knownLabels[labelValue.value]) {
                    context.reportError(new GraphQLError('Defer/Stream directive label argument must be unique.', { nodes: [knownLabels[labelValue.value], node] }));
                }
                else {
                    knownLabels[labelValue.value] = node;
                }
            }
        },
    };
}