Creating a Moodle Plugin for Moodle 5.0

Creating a plugin for Moodle 5.0 can be an exciting way to extend the platform's functionality to suit your educational needs. In this guide, we’ll walk through the essential steps of building a Moodle plugin, focusing on setting up a development environment, creating the plugin structure, adding core features, testing, and deployment.

1. Introduction: Why Create a Moodle Plugin?

Moodle is a highly customizable learning management system (LMS) widely used for online education. While Moodle offers a rich set of features, there are times when you need to develop custom functionality. Creating a plugin allows you to add specific features tailored to your institution’s requirements, such as displaying personalized data or integrating external systems.

2. Getting Started: Setting Up Your Development Environment

To create a Moodle plugin, follow these steps to prepare your environment:

Install Moodle 5.0: Set up a local Moodle instance using a web server like Apache, PHP (at least 8.0), and a database like MySQL.
Development Tools: Use a code editor like Visual Studio Code, Git for version control, and Composer for PHP dependency management.
Moodle Developer Mode: Enable debugging to catch errors during development by adding the following to config.php:
```
$CFG->debug = (E_ALL | E_STRICT);
$CFG->debugdisplay = 1;
```
Directory Structure: Moodle plugins reside in subdirectories of the /moodle/local/ or /moodle/mod/ folder, depending on the plugin type.

In Moodle, the directory structure for plugins is as follows:

Blocks: /blocks/
Modules (Activities): /mod/
Local Plugins: /local/
Reports: /report/
Auth Plugins: /auth/
Themes: /theme/
Course Formats: /course/format/

3. Creating the Basic Plugin Structure

Start by creating your plugin directory under /moodle/local/:

mkdir -p moodle/local/hashplugin
cd moodle/local/hashplugin

Inside this directory, create the following essential files:

version.php - Defines plugin metadata.
lang/en/local_hashplugin.php - Holds language strings.
db/access.php - Defines capabilities.
settings.php - Adds plugin configuration.
lib.php - Main logic.
index.php - Front-end page.
renderer.php - Defines how the plugin outputs content.

Example: version.php

defined('MOODLE_INTERNAL') || die();

$plugin->component = 'local_hashplugin';
$plugin->version = 2025050700;
$plugin->requires = 2024040100; // Moodle 5.0
$plugin->maturity = MATURITY_STABLE;
$plugin->release = 'v1.0';

4. Implementing Core Features

a. Displaying Student Hash

In lib.php, add a function to generate and display a hash:

function local_hashplugin_display_user_hash($userid) {
    global $DB;
    $user = $DB->get_record('user', array('id' => $userid));
    if ($user) {
        $hash = hash('sha256', $user->username);
        return "User Hash: " . $hash;
    }
    return "User not found.";
}

b. Flag Generation and Validation

In lib.php, add the flag generation logic:

function local_hashplugin_generate_flag($userid, $coursekey) {
    global $DB;
    $user = $DB->get_record('user', array('id' => $userid));
    if ($user) {
        $userhash = hash('sha256', $user->username);
        $flag = hash('sha256', $userhash . '-' . $coursekey);
        return "Flag: " . $flag;
    }
    return "Error generating flag.";
}

Display Example (index.php):

require('../../config.php');
require_once($CFG->dirroot . '/local/hashplugin/lib.php');

$userid = required_param('id', PARAM_INT);
echo local_hashplugin_display_user_hash($userid);

5. Testing the Plugin

Unit Testing: Write unit tests using Moodle’s built-in testing framework located in /tests.
Functional Testing:
- Navigate to Site administration -> Plugins -> Local plugins.
- Ensure the plugin appears and runs without errors.
Debugging: Check logs in moodledata for any warnings or issues.

Example Test Case:

public function test_display_user_hash() {
    $userid = 2;
    $output = local_hashplugin_display_user_hash($userid);
    $this->assertStringContainsString("User Hash:", $output);
}

6. Packaging and Deploying

Code Check: Run Moodle’s code checker tool to ensure compliance.
Package the Plugin:

zip -r hashplugin.zip local/hashplugin

Install the Plugin:
- Upload the ZIP via Site administration -> Plugins -> Install plugins.
- Follow the on-screen instructions to complete installation.
Upgrade Moodle Database:

php admin/cli/upgrade.php

7. Conclusion: Best Practices and Tips

Follow Moodle Coding Guidelines: This ensures compatibility and maintainability.
Use Moodle APIs: Always leverage built-in functions to avoid breaking changes in future Moodle updates.
Version Control: Maintain your plugin with version numbers and changelogs for each release.
Community Feedback: Share your plugin on Moodle's plugin directory to gather feedback and suggestions.

By following these steps, you can create a functional and robust Moodle plugin tailored to your specific requirements. Happy coding!