Event Registration Module

A comprehensive Drupal 10 custom module for managing event registrations with admin configuration, user registration, validation, email notifications, and reporting features.

Features

• Admin Event Configuration: Create and manage events with registration periods
• Public Registration Form: User-friendly form with AJAX-dependent dropdowns
• Validation: Email format, text field sanitization, and duplicate registration prevention
• Email Notifications: Automated emails to users and administrators
• Admin Dashboard: View and filter registrations with participant counts
• CSV Export: Export registration data for analysis
• Permissions: Role-based access control for all features

Installation

Prerequisites

• Drupal 10.x
• PHP 8.1 or higher
• MySQL 5.7+ or MariaDB 10.3+
• Composer

Steps

1. Copy the module to your Drupal installation:

   cp -r event_registration /path/to/drupal/web/modules/custom/

2. Enable the module using Drush:

   drush en event_registration -y

   Or enable via the Drupal admin interface:

   • Navigate to Extend (/admin/modules)
   • Find "Event Registration" under Custom modules
   • Check the box and click Install

3. Clear cache:

   drush cr

4. Configure permissions:

   • Navigate to People > Permissions (/admin/people/permissions)
   • Assign appropriate permissions to roles:
     • administer event registration - For administrators
     • access event registrations - For viewing registration lists
     • register for events - For users who can register

5. Configure email settings:

   • Navigate to Configuration > Event Registration Settings (/admin/config/event-registration/settings)
   • Enter admin email address
   • Enable/disable email notifications

Database Tables

event_configuration

Stores admin-created events with registration periods.

Field	Type	Description
id	INT (PK)	Unique event ID
reg_start_date	VARCHAR(20)	Registration start date (YYYY-MM-DD)
reg_end_date	VARCHAR(20)	Registration end date (YYYY-MM-DD)
event_date	VARCHAR(20)	Actual event date (YYYY-MM-DD)
event_name	VARCHAR(255)	Name of the event
category	VARCHAR(255)	Event category (e.g., Online Workshop)

Indexes:

• idx_category on category
• idx_event_date on event_date

event_registration

Stores user registrations for events.

Field	Type	Description
id	INT (PK)	Unique registration ID
full_name	VARCHAR(255)	Full name of the registrant
email	VARCHAR(255)	Email address of the registrant
college_name	VARCHAR(255)	College name of the registrant
department	VARCHAR(255)	Department of the registrant
category	VARCHAR(255)	Event category
event_date	VARCHAR(20)	Event date (YYYY-MM-DD)
event_id	INT (FK)	Foreign key to event_configuration table
created	INT	Timestamp when registration was created

Indexes:

• idx_email on email
• idx_event_date on event_date
• idx_event_id on event_id

Foreign Key:

• event_id references event_configuration(id) with CASCADE on delete

URLs and Pages

Admin Pages

URL	Permission Required	Description
/admin/config/event-registration/events	administer event registration	Create and configure events
/admin/config/event-registration/settings	administer event registration	Configure module settings
/admin/event-registration/list	access event registrations	View and filter registrations
/admin/event-registration/export	access event registrations	Export registrations to CSV

Public Pages

URL	Permission Required	Description
/event/register	register for events	Public event registration form

Validation Logic

The module implements comprehensive validation to ensure data integrity:

Email Validation

• Uses PHP's filter_var() with FILTER_VALIDATE_EMAIL
• Ensures proper email format (e.g., user@example.com)
• Applied to both user registration and admin settings

Text Field Validation

• Pattern: Only alphanumeric characters and spaces allowed
• Regex: /^[a-zA-Z0-9\s]+$/
• Applied to:
  • Full Name
  • College Name
  • Department
  • Event Name

Date Validation

• Registration end date must be after start date
• Event date must be on or after registration end date
• Prevents illogical date configurations

Duplicate Registration Prevention

• Check: Email + Event Date combination
• Query:

  SELECT id FROM event_registration 
  WHERE email = ? AND event_date = ?

• Error Message: "You are already registered for this event."
• Prevents users from registering multiple times for the same event

Email Functionality

Configuration

• Admin email address stored in event_registration.settings config
• Enable/disable toggle for notifications
• No hardcoded email addresses

Email Types

1. User Confirmation Email

Sent to: User's email address
Trigger: Successful registration
Contains:

• Full name
• Event name
• Event category
• Event date
• College name
• Department

2. Admin Notification Email

Sent to: Admin email (from settings)
Trigger: Successful registration
Contains:

• All participant details
• All event details

Implementation

• Uses Drupal Mail API via MailManagerInterface
• Dependency injection for testability
• Implements hook_mail() for message formatting
• Only sends if notifications are enabled in settings

AJAX Functionality

The registration form uses nested AJAX callbacks for dynamic field updates:

Category → Event Date

1. User selects a category
2. AJAX callback updateEventDates() triggers
3. Event date dropdown populates with dates for selected category
4. Only shows events where current date is within registration period

Event Date → Event Name

1. User selects an event date
2. AJAX callback updateEventNames() triggers
3. Event name dropdown populates with events matching category + date
4. Only shows active events

Active Event Filtering

Events are considered "active" when:

current_date >= reg_start_date AND current_date <= reg_end_date

Admin Features

Registration List

• Filtering: By event date and event name (AJAX-dependent)
• Display: Sortable table with all registration details
• Count: Shows total number of participants
• Pagination: Supports large datasets

CSV Export

• Format: Standard CSV with headers
• Filename: event_registrations_YYYY-MM-DD_HH-MM-SS.csv
• Columns:
  • Full Name
  • Email
  • College
  • Department
  • Category
  • Event Date
  • Event Name
• Filtering: Respects current filter selections

Architecture

Dependency Injection

All classes use proper dependency injection:

• Connection for database operations
• MailManagerInterface for email
• ConfigFactoryInterface for configuration

Best Practices

• ✅ No use of \Drupal::service() in classes
• ✅ Proper use of Config API
• ✅ Database API for all queries
• ✅ Form API for all forms
• ✅ Permissions on all routes
• ✅ Error handling and logging
• ✅ AJAX for better UX

File Structure

event_registration/
├── event_registration.info.yml          # Module metadata
├── event_registration.install           # Database schema and hooks
├── event_registration.module            # Hook implementations
├── event_registration.permissions.yml   # Permission definitions
├── event_registration.routing.yml       # Route definitions
├── event_registration.services.yml      # Service definitions
├── event_registration_schema.sql        # SQL export for submission
├── README.md                            # This file
└── src/
    ├── Controller/
    │   ├── RegistrationExportController.php    # CSV export
    │   └── RegistrationListController.php      # Admin listing
    ├── Form/
    │   ├── EventConfigForm.php                 # Admin event config
    │   ├── EventRegistrationForm.php           # Public registration
    │   ├── RegistrationFilterForm.php          # Admin filter form
    │   └── SettingsForm.php                    # Module settings
    └── Service/
        └── MailService.php                     # Email service

Usage Guide

For Administrators

1. Create an Event:

   • Go to /admin/config/event-registration/events
   • Fill in event details (name, category, dates)
   • Click "Create Event"

2. Configure Email Settings:

   • Go to /admin/config/event-registration/settings
   • Enter your admin email
   • Enable notifications if desired

3. View Registrations:

   • Go to /admin/event-registration/list
   • Use filters to narrow down results
   • View participant count

4. Export Data:

   • Apply desired filters
   • Click "Export to CSV"
   • Download the generated file

For Users

1. Register for an Event:
   • Go to /event/register
   • Fill in personal details
   • Select event category (dropdown populates from active events)
   • Select event date (based on category)
   • Select event name (based on category + date)
   • Click "Register"
   • Receive confirmation email

Troubleshooting

Emails Not Sending

• Check that notifications are enabled in settings
• Verify admin email is configured
• Check Drupal's mail configuration
• Review logs at /admin/reports/dblog
• Note for Localhost/XAMPP Users: If you are running this locally without a configured mail server (e.g., Sendmail/Postfix), you will see an "Unable to send email" error. This is expected behavior for the environment; the module logic is correct and will function properly on a live server.

AJAX Not Working

• Clear Drupal cache: drush cr
• Check browser console for JavaScript errors
• Ensure jQuery is loaded

No Events Showing in Registration Form

• Verify events are created in admin
• Check that current date is within registration period
• Ensure events have valid dates

Development Notes

Adding New Event Categories

Edit EventConfigForm.php line 68 to add options to the category dropdown.

Customizing Email Templates

Modify MailService.php methods:

• buildUserEmailBody() for user emails
• buildAdminEmailBody() for admin emails

Extending Validation

Add custom validation in form classes:

• EventConfigForm::validateForm()
• EventRegistrationForm::validateForm()

License

This module is provided as-is for educational purposes.

Support

For issues or questions, please contact the module maintainer or refer to Drupal.org documentation.

Version

Version: 1.0.0
Drupal: 10.x
Last Updated: February 2026