block21.js

// server/src/graphql/student.js
// import the "database" service
const { students } = require('../services/db');
...
const saveStudent = async (_, student, __, ___) => {
  try {
    // push the new student into the array
    students.push(student);

    // return the newly created student
    return student;
  } catch (err) {
    console.error('Error while trying to create student', err);
    throw new Error(INTERNAL_ERROR);
  }
};

const getStudents = (_, __, ___, ____) => {
  // return all the students
  return students;
};