Trivia API

This project is a full-stack trivia game where users can test their knowledge answering trivia questions. It is a TDD-based API with the following functionality:

1. Display questions:

   • All questions or by category.
   • Show the question, category, and difficulty.
   • Show/hide the answer.

2. Delete questions.

3. Add new questions with mandatory question and answer texts.

4. Search for questions based on a keyword.

5. Play the quiz game, randomizing either all questions or within a specific category.

Overview

Tech Stack

Tech stack includes:

• React.js and Sass for the website's frontend.
• Python3 and Flask as my server-side language and server-side framework.
• PostgreSQL as my database of choice.
• SQLAlchemy ORM to be my ORM library of choice.

Getting Started

Database Configuration

Make sure to have PostgreSQL installed, if it is not, execute:

sudo apt-get -y install postgresql

Create Database

First, start your PostgreSQL database server by running:

sudo service postgresql start

Then, create your project's database by running:

createdb trivia

Database Connection String

Add your database connection string as an environment variable by executing:

export DATABASE_URL=<db_connection_string> # e.g. postgresql://username:password@localhost:5432/database

Import Database

Make sure to be inside the /backend directory. To import the database schema and initial data, run:

psql trivia < trivia.psql

Installation and Running the Servers

Backend

Navigate to the /backend directory and make sure that you have Python3 installed.

Create Virtual Environment

Run the following to create a virtual environment:

python3 -m venv env

Activate your newly created virtual environment by running:

source env/bin/activate

Installing Backend Dependencies

To install backend dependencies, simply run:

pip install -r requirements.txt

Running the Backend Server

Prepare the development environment by executing:

export FLASK_APP=flaskr
export FLASK_ENV=development

To run the server at any time, use:

flask run

By default, the Flask server runs on http://localhost:5000.

Frontend Dependencies

Navigate to the /frontend directory and make sure that you have Node.js and npm installed first.

Installing Frontend Dependencies

To install backend dependencies, simply run:

npm install

Running the Frontend Server

To start the frontend server, run:

npm start

This will run the React frontend server at http://localhost:3000.

Testing

To run the tests, run

dropdb trivia_test
createdb trivia_test
psql trivia_test < trivia.psql
python3 test_flaskr.py

Omit the dropdb command the first time you run tests.

API Reference

• Base URL:

  • currently this application is only hosted locally.
  • The backend is hosted at http://127.0.0.1:5000/.

• Authentication: This version does not require authentication or API keys.

Error Handling

Errors are returned as JSON in the following format:

{
  "error": 404,
  "message": "resource not found",
  "success": false
}

The API returns three types of errors:

• 400: bad request.
• 404: resource not found.
• 422: unprocessable.

Endpoints

GET /categories

• General: returns a list of all categories.

• Sample: curl http://127.0.0.1:5000/categories

{
  "categories": [
    {
      "1": "Science"
    },
    {
      "2": "Art"
    },
    {
      "3": "Geography"
    },
    {
      "4": "History"
    },
    {
      "5": "Entertainment"
    },
    {
      "6": "Sports"
    }
  ],
  "success": true,
  "total_categories": 6
}

GET /questions

• General:

  • Returns a list questions.
  • Results are paginated in groups of 10.
  • Also returns a list of categories and the total number of questions.

• Sample: curl http://127.0.0.1:5000/questions

{
  "categories": [
    {
      "1": "Science"
    },
    {
      "2": "Art"
    },
    {
      "3": "Geography"
    },
    {
      "4": "History"
    },
    {
      "5": "Entertainment"
    },
    {
      "6": "Sports"
    }
  ],
  "questions": [
    {
      "answer": "Apollo 13",
      "category": 5,
      "difficulty": 4,
      "id": 2,
      "question": "What movie earned Tom Hanks his third straight Oscar nomination, in 1996?"
    },
    {
      "answer": "Tom Cruise",
      "category": 5,
      "difficulty": 4,
      "id": 4,
      "question": "What actor did author Anne Rice first denounce, then praise in the role of her beloved Lestat?"
    },
    {
      "answer": "Maya Angelou",
      "category": 4,
      "difficulty": 2,
      "id": 5,
      "question": "Whose autobiography is entitled 'I Know Why the Caged Bird Sings'?"
    },
    {
      "answer": "Edward Scissorhands",
      "category": 5,
      "difficulty": 3,
      "id": 6,
      "question": "What was the title of the 1990 fantasy directed by Tim Burton about a young man with multi-bladed appendages?"
    },
    {
      "answer": "Muhammad Ali",
      "category": 4,
      "difficulty": 1,
      "id": 9,
      "question": "What boxer's original name is Cassius Clay?"
    },
    {
      "answer": "Brazil",
      "category": 6,
      "difficulty": 3,
      "id": 10,
      "question": "Which is the only team to play in every soccer World Cup tournament?"
    },
    {
      "answer": "Uruguay",
      "category": 6,
      "difficulty": 4,
      "id": 11,
      "question": "Which country won the first ever soccer World Cup in 1930?"
    },
    {
      "answer": "George Washington Carver",
      "category": 4,
      "difficulty": 2,
      "id": 12,
      "question": "Who invented Peanut Butter?"
    },
    {
      "answer": "Lake Victoria",
      "category": 3,
      "difficulty": 2,
      "id": 13,
      "question": "What is the largest lake in Africa?"
    },
    {
      "answer": "The Palace of Versailles",
      "category": 3,
      "difficulty": 3,
      "id": 14,
      "question": "In which royal palace would you find the Hall of Mirrors?"
    }
  ],
  "success": true,
  "total_questions": 20
}

DELETE /questions/<int:id>

• General:

  • Deletes a question by id, using url parameters.
  • Returns the id of the deleted question upon success.

• Sample: curl http://127.0.0.1:5000/questions/6 -X DELETE

{
  "deleted": 6,
  "success": true
}

POST /questions

• General:

  • Creates a new question using JSON request parameters.
  • Returns JSON object with the newly created question id, as well as paginated questions.
  • Also returns the updated number of total questions.

• Sample: curl http://127.0.0.1:5000/questions -X POST -H "Content-Type: application/json" -d '{"question": "Which US state contains an area known as the Upper Penninsula?", "answer": "Michigan", "difficulty": 3, "category": "3"}'

{
  "created": 26,
  "questions": [
    {
      "answer": "Apollo 13",
      "category": 5,
      "difficulty": 4,
      "id": 2,
      "question": "What movie earned Tom Hanks his third straight Oscar nomination, in 1996?"
    },
    {
      "answer": "Tom Cruise",
      "category": 5,
      "difficulty": 4,
      "id": 4,
      "question": "What actor did author Anne Rice first denounce, then praise in the role of her beloved Lestat?"
    },
    {
      "answer": "Maya Angelou",
      "category": 4,
      "difficulty": 2,
      "id": 5,
      "question": "Whose autobiography is entitled 'I Know Why the Caged Bird Sings'?"
    },
    {
      "answer": "Edward Scissorhands",
      "category": 5,
      "difficulty": 3,
      "id": 6,
      "question": "What was the title of the 1990 fantasy directed by Tim Burton about a young man with multi-bladed appendages?"
    },
    {
      "answer": "Muhammad Ali",
      "category": 4,
      "difficulty": 1,
      "id": 9,
      "question": "What boxer's original name is Cassius Clay?"
    },
    {
      "answer": "Brazil",
      "category": 6,
      "difficulty": 3,
      "id": 10,
      "question": "Which is the only team to play in every soccer World Cup tournament?"
    },
    {
      "answer": "Uruguay",
      "category": 6,
      "difficulty": 4,
      "id": 11,
      "question": "Which country won the first ever soccer World Cup in 1930?"
    },
    {
      "answer": "George Washington Carver",
      "category": 4,
      "difficulty": 2,
      "id": 12,
      "question": "Who invented Peanut Butter?"
    },
    {
      "answer": "Lake Victoria",
      "category": 3,
      "difficulty": 2,
      "id": 13,
      "question": "What is the largest lake in Africa?"
    },
    {
      "answer": "The Palace of Versailles",
      "category": 3,
      "difficulty": 3,
      "id": 14,
      "question": "In which royal palace would you find the Hall of Mirrors?"
    }
  ],
  "success": true,
  "total_questions": 19
}

POST /questions/search

• General:

  • Searches for questions using search term in JSON request parameters.
  • Returns JSON object with paginated matching questions.
  • Also returns total number of matching questions.

• Sample: curl http://127.0.0.1:5000/questions/search -X POST -H "Content-Type: application/json" -d '{"search_term": "title"}'

{
  "questions": [
    {
      "answer": "Maya Angelou",
      "category": 4,
      "difficulty": 2,
      "id": 5,
      "question": "Whose autobiography is entitled 'I Know Why the Caged Bird Sings'?"
    },
    {
      "answer": "Edward Scissorhands",
      "category": 5,
      "difficulty": 3,
      "id": 6,
      "question": "What was the title of the 1990 fantasy directed by Tim Burton about a young man with multi-bladed appendages?"
    }
  ],
  "success": true,
  "total_results": 2
}

GET /categories/<int:category_id>/questions

• General:

  • Gets questions by category id, using url parameters.
  • Returns JSON object with paginated matching questions.
  • Also returns total number of the category's questions.

• Sample: curl http://127.0.0.1:5000/categories/1/questions

{
  "current_category": 2,
  "questions": [
    {
      "answer": "Escher",
      "category": 2,
      "difficulty": 1,
      "id": 16,
      "question": "Which Dutch graphic artist–initials M C was a creator of optical illusions?"
    },
    {
      "answer": "Mona Lisa",
      "category": 2,
      "difficulty": 3,
      "id": 17,
      "question": "La Giaconda is better known as what?"
    },
    {
      "answer": "One",
      "category": 2,
      "difficulty": 4,
      "id": 18,
      "question": "How many paintings did Van Gogh sell in his lifetime?"
    }
  ],
  "success": true,
  "total_results": 3
}

POST /quiz

• General:

  • Allows users to play a quiz game.
  • Uses JSON request parameters of category and previous questions.
  • Returns JSON object with a random question that is not among previous questions.

• Sample: curl http://127.0.0.1:5000/quiz -X POST -H "Content-Type: application/json" -d '{"previous_questions": [20, 21], "category": 1}'

{
  "question": {
    "answer": "Blood",
    "category": 1,
    "difficulty": 4,
    "id": 22,
    "question": "Hematology is a branch of medicine involving the study of what?"
  },
  "success": true
}

Authors

Ahmed Baligh authored the API (__init__.py), test suite (test_flaskr.py), and this README. Mohamed Agina along with Ahmed Baligh made major updates and improvement to all the files the (/frontend) directory.

All other project files, including the models and structure of frontend, were created by Udacity as a project template for the Full Stack Web Developer Nanodegree.