Math Parser Drupal 8 Module

This Drupal 8 module provides a mathematical string parser service, field type, and configurable field formatter.

Getting started

Prerequisites

You will need a working Drupal 8 instance with the module dependencies installed.

composer require drupal/graphql_views and then install within Drupal. This will also install GraphQL.

Module Dependencies

• GraphQL Drupal Module
• GraphQL Views Drupal Module

Installing

1. Include this module in the /modules folder of a Drupal 8 instance.
2. Navigate to js/app and run npm install and then npm run build.
3. Navigate to /admin/modules and install Math Parser and Math Parser Example, found under the Field Types category. This will create an example content type called Maths quiz and a view called Math Parser Example (used for GraphQL request from the React app).
4. Create a piece of Maths quiz content, demonstrated below.

Overview

Field formatter widget options

• React displays the formulas as an interactive React quiz. This only works when using the Math Parser field type.
• Twig will render the field without loading the React javascript and display it in the following format {{formula}} = {{result}}. This formatter widget option can also work on Text (plain) field types.
• Answer only will render just the answer. This is used within the GraphQL view to return only the answer when checking if the user input is correct. This formatter widget option can also work on Text (plain) field types.

By default, the field formatter will display the formulas in an interactive quiz as seen below. Put in your answer and hit the enter key.

Drupal Service

This module provides the MathParser service, found in src/Services/MathParser.php. You can access this like any other Drupal service - see the example below.

      $string = '2+2';  
      $math_parser = \Drupal::Service('math_parser.math_parser');
      $parsed_value = $math_parser->calculate($string);

React

When using the React widget option for the field formatter, a progressively decoupled React app using Webpack is included within the Math Parser field template. This uses GraphQL to retrieve the formula solution when a user enters their answer, and after three attempts or a correct answer, the user is given the next formula.

Please note that currently the React requests using GraphQL won't work without the Math Parser Example module enabled as the GraphQL query depends on a specific view that references fields that are also generated upon installation of the example module.

Running the tests

You may need to run composer run-script drupal-phpunit-upgrade if PHPUnit testing framework is out of date.

Module unit tests can be found in tests/src/Unit and run using PHPUnit.

Recommended: create phpunit.xml.dist (using config similar to the below example in root of project and run ./vendor/bin/phpunit

<?xml version="1.0" encoding="UTF-8"?>
<phpunit bootstrap="core/tests/bootstrap.php" colors="true">
  <testsuites>
    <testsuite name="unit">
      <directory>modules/custom/math_parser/tests</directory>
    </testsuite>
  </testsuites>
</phpunit>