📝 Quiz App

Welcome! As the world's largest interview prep community and learning platform, we're always working to build better learning experiences for our users. This project is designed to give you a fun, hands-on example of what it would be like to develop products at Exponent.

Assignment

In this takehome assignment, you'll be building the API for a simple Quiz app that allows the user to take a multiple choice quiz, which will be graded automatically by the server for instant feedback.

The user interface for the quiz won't be part of this project—instead it's up to you to create the backend API that the UI will eventually integrate with. Don't worry about persisting data or user authentication for now–that's out of scope for this project.

Note: We've set up a simple server using Node and Express.js to make it easier to get started with building. You should be able to accomplish the project without additional dependencies, but feel free to import more libraries if you want.

Here's the list of features we'd like our app to support:

• Fetching quiz data from the API
• Submitting quiz answers and returning the grade to the client
• Test coverage - we've stubbed out a few test cases for you to get started

You can refer to the documentation below to understand what API endpoints to implement.

Evaluation

We'll evaluate your submission on the following criteria:

• Functionality: Does your solution work as intended and meet the spec for the API? Do you handle errors correctly?
• Craft: Does your code follow best practices and expected behavior? Is your code easy to read and commented appropriately?

Development

To get started, download the repo or click "Use this template" to create a private version of this project. After downloading the repo, go to the directory and run

npm install

followed by

npm start

You can access the local server at localhost:3000. You can then create or modify files in the src/ directory.

To run the tests (not yet implemented), run npm test.

API Documentation

GET /api/quizzes

Returns an array of available quizzes, with title and ID.

Response

Key	Type	Description
id	String	A unique identifier for the quiz, e.g. 'math'
title	String	The human-readable title of the quiz

GET /api/quizzes/:id

Returns a Quiz object to the client given a valid quiz ID, omitting the correct answers. Quiz content is available in data/quizzes.json which you can use in your implementation. Returns a 404 if the requested quiz cannot be found.

Request

Key	Type	Description
id	String	A unique identifier for the quiz

Response

Key	Type	Description
id	String	A unique identifier for the quiz, e.g. 'math'
title	String	The human-readable title of the quiz
questions	Array<Question>	An array of multiple choice questions

Question Format

Key	Type	Description
id	String	An id for the question, unique to this quiz, e.g. "question_1"
text	String	The text content of the question
options	Array<String>	A list of multiple choice options

Example response:

{
  "id": "example",
  "title": "My Quiz",
  "questions": [{
    "id": "question_1",
    "text": "What is 1 + 1?",
    "options": ["1", "2", "3"]
  }, {
    "id": "question_2",
    "text": "True or false: 2 + 2 = 4",
    "options": ["True", "False"]
  }]
}

POST /api/quizzes/:id/attempt

Handles submitting a quiz attempt and returns a graded result showing which questions were correct and incorrect.

Request

Key	Type	Description
answers	{[id: String]: String}	An object mapping ID of each question to the user-provided value

Response

Key	Type	Description
correct	Number	Number of correct answers
incorrect	Number	Number of incorrect answers
questions	{[id: String]: Boolean}	An object mapping ID of each question to the graded result, where true represents a correct answer.

// POST /api/quizzes/math/attempt
{
  "answers": {
    "question_1": "2",
    "question_2": "False"
  }
}

// Response
{
  "correct": 1,
  "incorrect": 1,
  "questions": {
    "question_1": true,
    "question_2": false,
  }
}

What you should submit

Please share your private fork with us or send a .zip file over email. If necessary, please provide any additional notes to run or test the application.