text: // Initializes the `graphql` service on path `/graphql`
  const graphqlHTTP = require('express-graphql');
  const { buildSchema } = require('graphql');
  
  module.exports = function (app) {
    const schema = buildSchema(`
      type Query {
        hello: String
      }
    `);
    const rootValue = {
      hello: () => {
        return 'Hello world!';
      },
    };
    // Initialize our service with any options it requires
    app.use('/graphql', graphqlHTTP({
      schema,
      rootValue,
      graphiql: true,
    }));
  };
  