@theguild/federation-composition/esm/subgraph/validation/rules/reserved-subgraph-name-rule.js

Open Source Composition library for Apollo Federation

import { GraphQLError } from 'graphql';
export function ReservedSubgraphNameRule(context) {
    if (context.getSubgraphName() === '_') {
        context.reportError(new GraphQLError(`Invalid name _ for a subgraph: this name is reserved`, {
            extensions: {
                code: 'INVALID_SUBGRAPH_NAME',
            },
        }));
    }
    return {};
}