graphql-yoga/esm/plugins/useUnhandledRoute.js

<div align="center"><img src="./website/public/cover.png" width="720" /></div>

import landingPageBody from '../landing-page-html.js';
export function useUnhandledRoute(args) {
    let urlPattern;
    function getUrlPattern({ URLPattern }) {
        urlPattern || (urlPattern = new URLPattern({
            pathname: args.graphqlEndpoint,
        }));
        return urlPattern;
    }
    return {
        onRequest({ request, fetchAPI, endResponse, url }) {
            if (!request.url.endsWith(args.graphqlEndpoint) &&
                url.pathname !== args.graphqlEndpoint &&
                !getUrlPattern(fetchAPI).test(url)) {
                if (args.showLandingPage === true &&
                    request.method === 'GET' &&
                    !!request.headers?.get('accept')?.includes('text/html')) {
                    endResponse(new fetchAPI.Response(landingPageBody
                        .replace(/__GRAPHIQL_LINK__/g, args.graphqlEndpoint)
                        .replace(/__REQUEST_PATH__/g, url.pathname), {
                        status: 200,
                        statusText: 'OK',
                        headers: {
                            'Content-Type': 'text/html',
                        },
                    }));
                    return;
                }
                endResponse(new fetchAPI.Response('', {
                    status: 404,
                    statusText: 'Not Found',
                }));
            }
        },
    };
}