Quiz Answer Validator

This project exposes a Node.js library allowing to check if an answer given by a player to a quiz question is correct or not. To validate or invalidate the answer, the library relies on a list of valid acceptable answers and on a set of algorithmic rules detailed in a dedicated section below.

Usage

Installation using npm:

$ npm install quiz-answer-validator

Import:

// using ECMAScript module format
import answerIsValid from 'quiz-answer-validator';

// using CommonJS module format
const answerIsValid = require('quiz-answer-validator').default;

Usage:

• 1st param {string} - inputAnswer: Player's input answer to be checked
• 2nd param {string[]} - acceptableAnswers: Array of acceptable answers
• 3rd param number - [maxTypoRate=0.15]: Maximum tolerated typo rate between 0 and 1 (default 0.15)

// With default typo rate

answerIsValid('Herve Matoux', ['Hervé Mathoux', 'Mathoux']);          // true
answerIsValid('mathou', ['Hervé Mathoux', 'Mathoux']);                // true
answerIsValid('Hervais Mattou', ['Hervé Mathoux', 'Mathoux']);        // false

answerIsValid('big lebowski', ['The Big Lebowski']);                  // true
answerIsValid('The Big Lebowski', ['The Big Lebowski']);              // true
answerIsValid('big leboski', ['The Big Lebowski']);                   // false

answerIsValid('10000000', ['10.000.000']);                            // true
answerIsValid('10,000.000', ['10.000.000']);                          // true
answerIsValid('10.000.000', ['10000000']);                            // true
answerIsValid('10.000.0000', ['10.000.000']);                         // false


// With custom typo rate

answerIsValid('The Big Lebowski', ['The Big Lebowski'], 0);           // true
answerIsValid('The Big Lebowskii', ['The Big Lebowski'], 0);          // false
answerIsValid('The Big Lebowsk', ['The Big Lebowski'], 0);            // false
answerIsValid('bi lebow', ['The Big Lebowski'], 0.9);                 // true

Algorithmic rules

"Purification" of the input strings:

• replacing capital letters;
• replacing diacritics;
• replacing ligatures;
• finally keeping only alphanumeric characters.

Checking the maximum tolerated typo rate:

• using Sørensen–Dice coefficient;
• invalidating the player's answer if the rate is greater than 15% (optionally customizable), relative to the closest acceptable answer.

Particular case:

• if an expected answer contains only digits, no typos should be allowed, so the typo rate is not calculated.

Support

Tested with Node.js long-term support versions 14, 16 and 18.

Built for both ECMAScript and CommonJS module formats.

Automated CI test runs available.