Full Stack Trivia API

Full Stack Trivia

Full stack trivia is a way for Udacity's employees and students to connect with each other. Allowing them to create bonding experiences by placing trivia once a week.

API Description

1. Displays questions — both by all questions and by category. Questions has the ability to show the question, category and difficulty rating. Answers are hidden and can be shown with the press of a button.
2. Questions can be deleted with the press of a button.
3. Questions can be added, text for question and answer are required.
4. All questions can be searched, based on text query string.
5. The game is played by category or all questions, in a random order.

Local Requirements

Requires Python 3.7 or later

Python 3.7

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

Virtual Environment

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

PIP Dependencies

Once you have your virtual environment setup and running, install dependencies by navigating 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 micro-services 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 en sure 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.

Full Stack Trivia API Frontend

Getting Setup

tip: the frontend is designed to work with Flask-based Backend. It is recommended you stand up the backend first, test using Postman or curl, update the endpoints in the frontend, and then the frontend should integrate smoothly.

Installing Dependencies

Installing Node and NPM

This project depends on Nodejs and Node Package Manager (NPM). Before continuing, you must download and install Node (the download includes NPM) from https://nodejs.com/en/download.

Installing project dependencies

This project uses NPM to manage software dependencies. NPM Relies on the package.json file located in the frontend directory of this repository. After cloning, open your terminal and run:

npm install

tip: npm i is shorthand for npm install

Required Tasks

Running Your Frontend in Dev Mode

The frontend app was built using create-react-app. In order to run the app in development mode use npm start. You can change the script in the package.json file.

Open http://localhost:3000 to view it in the browser. The page will reload if you make edits.

npm start

Endpoints

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 an object of id: category_string key:value pairs.

Example: curl http://localhost:5000/categories

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

GET '/questions'

• Fetches a dictionary of questions, paginated in groups of 10.
• Returns JSON object of categories, questions dictionary with answer, category, difficulty, id and question.

Example: curl http://localhost:5000/questions

{
    "categories": [
        "Science",
        "Art",
        "Geography",
        "History",
        "Entertainment",
        "Sports"
    ],
    "current_category": [],
    "questions": [
        {
            "answer": "Apollo 13",
            "category": 5,
            "difficulty": 4,
            "id": 2,
            "question": "What movie earned Tom Hanks his third straight Oscar nomination, in 1996?"
        }
        ... # omitted for brevity 
    ],
    "success": true,
    "total_questions": 33
}

DELETE '/questions/int:question_id'

• Deletes selected question by id
• Returns 200 if question is successfully deleted.
• Returns 404 if question did not exist
• Returns JSON object of deleted id, remaining questions, and length of total questions

Example: curl -X DELETE http://localhost:5000/question/2

{
    "deleted": 2,
    "questions": [
        {
            "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?"
        }    
        ... # omitted for brevity 
    ],
    "success": true,
    "total_questions": 32
}

POST '/questions'

• Creates a new question posted from the react front end.
• Fields are: answer, difficulty and category.
• Returns a success value and ID of the question.
• If search field is present will return matching expressions

Example (Create): curl http://localhost:5000/questions -X POST -H "Content-Type: application/json" -d '{"question":"Who is Tony Stark?", "answer":"Iron Man", "category":"4", "difficulty":"2"}'

{
... # shortened for brevity
  "success": true, 
  "total_questions": 35
}

Example (Search):
curl http://localhost:5000/questions -X POST -H "Content-Type: application/json" -d '{"searchTerm":"Lestat"}'

{
  "questions": [
    {
      "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?"
    }
  ], 
  "success": true, 
  "total_questions": 1
}

GET '/categories/<cat_id>/questions'

• Returns JSON response of current_category, and the questions pertaining to that category

Example: curl http://localhost:5000/categories/1/questions

{
 "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?"
    }, 
   ... # omitted for brevity
  ], 
  "success": true, 
  "total_questions": 6
}

POST '/quizzes'

• Generates a quiz based on category or a random selection depending on what the user chooses.
• Returns a random question

Example: curl http://localhost:5000/quizzes -X POST -H "Content-Type: application/json" -d '{"previous_questions":[], "quiz_category":{"type":"Art","id":2}}'

{
  "question": {
    "answer": "One", 
    "category": 2, 
    "difficulty": 4, 
    "id": 18, 
    "question": "How many paintings did Van Gogh sell in his lifetime?"
  }, 
  "success": true
}

Error Handlers

When an error occurs a JSON response is returned

• Returns these error types when the request fails
  • 400: Bad Request
  • 404: Resource Not Found
  • 422: Not Processable
  • 500: Internal Server Error Example "Resource Not Found":

{
	"success": False,
	"error": 404,
	"message": "Resource Not Found"
}

Testing

To run the tests, run

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