Moodle External API Development

This skill guides you through creating custom external web service APIs for Moodle LMS, following Moodle's external API framework and coding standards.

When to Use This Skill

• Creating custom web services for Moodle plugins
• Implementing REST/AJAX endpoints for course management
• Building APIs for quiz operations, user tracking, or reporting
• Exposing Moodle functionality to external applications
• Developing mobile app backends using Moodle

Core Architecture Pattern

Moodle external APIs follow a strict three-method pattern:

1. execute_parameters() - Defines input parameter structure
2. execute() - Contains business logic
3. execute_returns() - Defines return structure

Step-by-Step Implementation

🧠 Knowledge Modules (Fractal Skills)

1. Step 1: Create the External API Class File

2. Step 2: Define Input Parameters

3. Step 3: Implement Business Logic

4. Step 4: Define Return Structure

5. Step 5: Register the Service

6. Step 6: Implement Error Handling & Logging

7. Complex Database Operations

8. Working with Course Modules

9. Access Restrictions (Groups/Availability)

10. Random Question Selection with Tags

11. 1. Via Moodle Web Services Test Client

12. 2. Via curl

13. 3. Via JavaScript (AJAX)

14. 1. "Function not found" Error

15. 2. "Invalid parameter value detected"

16. 3. SQL Injection Vulnerabilities

17. 4. Permission Denied Errors

18. 5. Transaction Deadlocks

19. Simple Read API (Get Quiz Attempts)

20. Complex Write API (Create Quiz from Categories)