GraphQL API route with remote schema

graphql.ts

// See: https://github.com/vercel/next.js/blob/canary/examples/api-routes-apollo-server/pages/api/graphql.js

import {AsyncExecutor} from '@graphql-tools/delegate';
import {introspectSchema, wrapSchema} from '@graphql-tools/wrap';
import {ApolloServer} from 'apollo-server-micro';
import {print} from 'graphql';
import fetch from 'isomorphic-unfetch';
import {NextApiRequest, NextApiResponse} from 'next';
import getConfig from 'next/config';

const {serverRuntimeConfig} = getConfig();

const createSchema = async () => {
  const executor: AsyncExecutor = async ({document, variables}) => {
    const query = print(document);
    const result = await fetch(serverRuntimeConfig.githubEndpoint, {
      method: 'POST',
      headers: {'Content-Type': 'application/json'},
      body: JSON.stringify({query, variables}),
    });
    return result.json();
  };
  return wrapSchema({
    executor,
    schema: await introspectSchema(executor),
  });
};

export default async function graphql(
  req: NextApiRequest,
  res: NextApiResponse
) {
  return new ApolloServer({
    schema: await createSchema()
  }).createHandler({path: '/api/graphql'})(req, res);
}

export const config = {
  api: {
    bodyParser: false,
  },
};