This project allows users to play a trivia game and test their general knowledge. In this project I created an API and unit test cases for the application that allows the following:

1. Displaying questions - both all questions and by category. The app shows questions, category and difficulty rating by default and can show/hide the answer.
2. Deleting questions.
3. Adding questions and require that they include question and answer text.
4. Searching for questions based on a text query string.
5. Playing the quiz game, randomizing either all questions or within a specific category.

When a user plays the game they play up to five questions of the chosen category. If there are fewer than five questions in a category, the game ends when there are no more questions left in that category.

All backend code follows PEP8 style guidelines.

The backend uses Python v3.10 All required packages are included in the requirements file. From the backend folder run pip install -r requirements.txt.

• Key Dependencies:
  • Flask
  • Flask-SQLAlchemy
  • Flask-CORS
  • Flask-Testing
  • Flask-Expects-Json
  • Flask-Migrate

1. The backend based on the PostgreSQL DBMS. You need to set up a database with the following command: createdb trivia. You may want to change the database name and path in the backend/config.py file.
2. After setting up the database run flask db upgrade command. It will create all the database tables and populate them with some seed data.

Start the backend application with the following commands:

export FLASK_APP=flaskr
export FLASK_ENV=development
flask run

These commands put the application in development mode and directs the application to use the __init__.py file in backend/flaskr folder. If running locally on Windows, look for the commands in the Flask documentation.

The application is run on http://127.0.0.1:5000/ by default and is a proxy in the frontend configuration.

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

This project uses NPM to manage software dependencies. NPM Relies on the package.json file located in the frontend directory of this repository.

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

1. In order to run tests you need to create a separate database. You can use the following command to create one: createdb trivia_test. You can change the database name and path in the backend/test_flaskr.py file.
2. After that you can use the python test_flaskr.py or python3 test_flaskr.py commands to execute the test cases. The test_flaskr.py file uses the same migration method and seed data as the flaskr application.

All tests are kept in that file and should be maintained as updates are made to app functionality.

Base URL: At present this app can only be run locally and is not hosted as a base URL. The backend app is hosted at the default, http://127.0.0.1:5000, which is set as a proxy in the frontend configuration.

Authentication: This version of the application does not require authentication or API keys.

Errors are returned as JSON objects in the following format:

{
    "error": 400,
    "message": "bad request"
}

The API will return three error types when requests fail:

• 400: Bad Request
• 404: Resource Not Found
• 405: Method Not Allowed
• 422: Not Processable

• Description:
  • 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 request: curl http://127.0.0.1:5000/api/v1.0/categories
• Example response:

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

• Description:
  • Fetches a paginated set of questions, a total number of questions, all categories and current category string.
  • Request Arguments: page - integer
  • Returns: An object with 10 paginated questions, the number of total questions, and an object including all categories. The current category string is not used.
• Example request: curl http://127.0.0.1:5000/api/v1.0/questions?page=1
• Example response:

  {
  "categories": {
      "1": "History", 
      "2": "Entertainment", 
      "3": "Sports", 
      "4": "Geography", 
      "5": "Art", 
      "6": "Science"
  }, 
  "currentCategory": null, 
  "questions": [
      {
      "answer": "Maya Angelou", 
      "category": 1, 
      "difficulty": 2, 
      "id": 1, 
      "question": "Whose autobiography is entitled 'I Know Why the Caged Bird Sings'?"
      }, 
      {
      "answer": "Muhammad Ali", 
      "category": 1, 
      "difficulty": 1, 
      "id": 2, 
      "question": "What boxer's original name is Cassius Clay?"
      }, 
      {
      "answer": "Apollo 13", 
      "category": 2, 
      "difficulty": 4, 
      "id": 3, 
      "question": "What movie earned Tom Hanks his third straight Oscar nomination, in 1996?"
      }
  ], 
  "totalQuestions": 3
  }

• Description:
  • Fetches questions for a category specified by id request argument.
  • Request Arguments: id - integer
  • Returns: An object with questions for the specified category, the number of total questions, and current category string.
• Example request: curl http://127.0.0.1:5000/api/v1.0/categories/1/questions
• Example response:

  {
  "currentCategory": "History", 
  "questions": [
      {
      "answer": "Maya Angelou", 
      "category": 1, 
      "difficulty": 2, 
      "id": 1, 
      "question": "Whose autobiography is entitled 'I Know Why the Caged Bird Sings'?"
      }, 
      {
      "answer": "Muhammad Ali", 
      "category": 1, 
      "difficulty": 1, 
      "id": 2, 
      "question": "What boxer's original name is Cassius Clay?"
      }
  ], 
  "totalQuestions": 2
  }

• Description:
  • Deletes a specified question using the id of the question.
  • Request Arguments: id - integer
  • Returns: Does not return anything.
• Example request: curl -X DELETE http://127.0.0.1:5000/api/v1.0/questions/{id}

• Description:
  • Sends a post request in order to add a new question.
  • Request Body:

    {
        "question":  "Here's a new question string",
        "answer": "Here's a new answer string",
        "difficulty": 1,
        "category": 3
    }

  • Returns: Does not return any new data.
• Example request: curl -X POST http://127.0.0.1:5000/api/v1.0/questions -H "Content-Type: application/json" -d "{\"question\": \"What is my name?\", \"answer\": \"Anonymous\", \"difficulty\": 5, \"category\": 1}"

• Description:
  • Sends a post request in order to search for a specific question by search term.
  • Request Body:

    {
        "searchTerm": "this is the term the user is looking for"
    }

  • Returns: Any array of questions, a number of totalQuestions that met the search term and the current category string.
• Example request: curl -X POST http://127.0.0.1:5000/api/v1.0/questions -H "Content-Type: application/json" -d "{\"searchTerm\": \"which\"}"

• Description:
  • Sends a post request in order to get the next question.
  • Request Body:

  {
      "previous_questions":  [1, 4, 20, 15],
      "quiz_category": "History" 
  }

  • Returns: A single new question object.
• Example request: curl http://127.0.0.1:5000/api/v1.0/quizzes -X POST -H "Content-Type: application/json" -d "{\"previous_questions\": [1, 2, 3], \"quiz_category\": {\"type\": \"Science\", \"id\": 1}}"
• Example response:

  {
      "question": {
              "id": 1,
              "question": "This is a question",
              "answer": "This is an answer", 
              "difficulty": 5,
              "category": 4
      }
  }