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

Defer/Stream plugin for GraphQL Yoga.

import { Kind } from 'graphql';
import { createGraphQLError } from 'graphql-yoga';
import { GraphQLDeferDirective, GraphQLStreamDirective } from '@graphql-tools/utils';
/**
 * 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(createGraphQLError(`Directive "${node.name.value}"'s label argument must be a static string.`, { nodes: node }));
                }
                else if (knownLabels[labelValue.value]) {
                    context.reportError(createGraphQLError('Defer/Stream directive label argument must be unique.', {
                        nodes: [knownLabels[labelValue.value], node],
                    }));
                }
                else {
                    knownLabels[labelValue.value] = node;
                }
            }
        },
    };
}