Full Stack Trivia API Backend

Full Stack Trivia

Udacity is invested in creating bonding experiences for its employees and students. A bunch of team members got the idea to hold trivia on a regular basis and created a webpage to manage the trivia app and play the game, but their API experience is limited and still needs to be built out.

The application has the following features:

1. Display questions - both all questions and by category. Questions should show the question, category and difficulty rating by default and can show/hide the answer.
2. Delete questions.
3. Add questions and require that they include question and answer text.
4. Update questions.
5. Play the quiz game, randomizing either all questions or within a specific category.

API Endpoints Documentation

GET '/categories'

• Fetches a dictionary of categories in which the keys are the ids and the value is the corresponding string of the category
• Request Arguments: None
• Returns: An object with a single key, categories, that contains a object of id: category_string key:value pairs.

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

GET '/questions'

• Fetches a dictionary of categories in which the keys are the ids and the value is the corresponding string of the category
• Fetches a list of questions.
• Request Arguments: Page Number
• Returns: Dictionary of Categories, current category, list of questions and total number of questions.

{
	"categories": {
		"1": "Science",
		"2": "Art",
		"3": "Geography",
		"4": "History",
		"5": "Entertainment",
		"6": "Sports"
	},
	"current_category": null,
	"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?"
		}
	],
	"total_questions": 26,
	"success": true
}

DELETE '/questions/<int:question_id>'

• Deletes question from the database.
• Request Arguments: questions_id
• Returns: true with status 204 if successfully deleted.

{
    "success": true
}

POST '/questions'

• Create a new question
• Request Body: question, answer, difficulty and category.
• Returns: true and question id with status 201 if successfully created.

Request

{
    "question": "Test question",
    "answer": "Answer",
    "category": 1,
    "difficulty": 1
}

Response

{
    "success": true,
    "id": 15
}

PATCH '/questions<int:question_id>'

• Updates the question.
• Request Arguments: questions_id
• Request Body: question, answer, difficulty and category.
• Returns: true and question id with status 200 if successfully updated.

Request

id=1

{
    "question": "Test question",
    "answer": "Answer",
    "category": 1,
    "difficulty": 1
}

Response

{
    "question": "Test question",
    "answer": "Answer",
    "category": 1,
    "difficulty": 1,
    "id": 1
}

POST '/categories/<int:category_id>/questions'

• To get questions based on category
• Request Arguments: category_id
• Returns: List of questions, total number of questions and current category.

{
	"current_category": {
		"id": 1,
		"type": "Science"
	},
	"questions": [
		{
			"answer": "The Liver",
			"category": 1,
			"difficulty": 4,
			"id": 20,
			"question": "What is the heaviest organ in the human body?"
		},
		{
			"answer": "Alexander Fleming",
			"category": 1,
			"difficulty": 3,
			"id": 21,
			"question": "Who discovered penicillin?"
		}
	],
	"total_questions": 13,
	"success": true
}

POST '/quizzes'

• In order to play the quiz.
• Returns: Random question within the given category.

Request

{
    "quiz_category": {
        "id": 1
    },
    "previous_questions": []
}

Response

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

Errors

Bad Request 400

{
  'success': false,
  'error': 400,
  'message': 'Bad Request'
}

Unauthorized 401

{
  'success': false,
  'error': 401,
  'message': 'Unauthorized'
}

Forbidden 403

{
  'success': false,
  'error': 403,
  'message': 'Forbidden'
}

Not Found 404

{
  'success': false,
  'error': 404,
  'message': 'Not Found'
}

Method Not Allowed 405

{
  'success': false,
  'error': 405,
  'message': 'Method Not Allowed'
}

Unprocessable Entity 422

{
  'success': false,
  'error': 422,
  'message': 'Unprocessable Entity'
}

Internal Server Error 500

{
  'success': false,
  'error': 500,
  'message': 'Internal Server Error'
}

Permissions Documentation

• add:question permission to add question through through POST '/questions' api
• edit:question permission to update question through PATCH '/questions<int:question_id>' api
• delete:question permission to delete question through through DELETE '/questions<int:question_id>' api
• play:quiz permission to play quiz through POST '/quizzes' api

Roles Documentation

Admin

Can add/update/delete question

Permissions:

• add:question
• edit:question
• delete:question

Player

Can play quiz

Permissions:

• play:quiz

Development environment setup

Installing Dependencies

Python 3.7

Follow instructions to install the latest version of python for your platform in the python docs

Virtual Enviornment

We recommend working within a virtual environment whenever using Python for projects. This keeps your dependencies for each project separate and organaized. Instructions for setting up a virual enviornment for your platform can be found in the python docs

PIP Dependencies

Once you have your virtual environment setup and running, install dependencies by naviging to the /backend directory and running:

pip install -r requirements.txt

This will install all of the required packages we selected within the requirements.txt file.

Key Dependencies

• Flask is a lightweight backend microservices framework. Flask is required to handle requests and responses.

• SQLAlchemy is the Python SQL toolkit and ORM we'll use handle the lightweight sqlite database. You'll primarily work in app.py and can reference models.py.

• Flask-CORS is the extension we'll use to handle cross origin requests from our frontend server.

Database Setup

With Postgres running, restore a database using the trivia.psql file provided. From the backend folder in terminal run:

psql trivia < trivia.psql

Running the server

From within the backend directory first ensure you are working using your created virtual environment.

To run the server, execute:

export FLASK_APP=flaskr
export FLASK_ENV=development
flask run

Setting the FLASK_ENV variable to development will detect file changes and restart the server automatically.

Setting the FLASK_APP variable to flaskr directs flask to use the flaskr directory and the __init__.py file to find the application.

Testing

To run the tests, run

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

Tokens to test the api end points are added in the role_tokens.json file.

The below link is used to retrieve tokens.

https://udacityfsnd.auth0.com/authorize?audience=capstone&response_type=token&client_id=hZOMNJb2DXT6khq5FWsmeblr7SE3wUNz&redirect_uri=http://localhost:5000/

safi.ullah@arbisoft.com has the Admin role and test.arbisofterp@gmail.com has the Player role.

Web app is deployed at:

https://udacity-demo.herokuapp.com/