Architecture

Overview

WP Appointments is a monorepo with a WordPress plugin at its core and shared npm packages for the frontend.

PHP Backend

Namespace: WPAppointments\ with PSR-4 autoloading.

Directory	Purpose
src/Api/Endpoints/	REST controllers extending base Controller
src/Core/	Plugin bootstrap, post types, capabilities, Singleton base class
src/Data/Model/	Data models: Appointment, Customer, BookableEntity, BookableVariant
src/Data/Query/	Query classes for fetching/filtering posts
src/Bookable/	Bookable type registry and abstract handler
src/Availability/	Layered availability engine and layer registry
src/Notifications/	Email notification system
src/Utils/	Date, Schedule, Availability helpers

Custom Post Types

CPT	Slug
Appointment	wpa-appointment
Schedule	wpa-schedule
Service	wpa-service
Entity	wpa-entity

Key Patterns

• Singleton pattern — most core classes extend Core\Singleton
• Bookable Type Registry — addons register handlers via BookableTypeRegistry::register()
• Availability Layers — addons register layers via AvailabilityLayerRegistry::register()
• Capabilities — filterable: wpa_manage_appointments, wpa_manage_customers, etc.

TypeScript Frontend

Directory	Purpose
assets/backend/	React admin UI (Dashboard, Calendar, Customers, Settings)
assets/backend/store/	@wordpress/data Redux store
assets/backend/api/	API client functions using @wordpress/api-fetch
assets/frontend/	Customer-facing booking flow
assets/gutenberg/blocks/	Booking Flow Gutenberg block

State Management

Uses @wordpress/data Redux stores. Actions, reducers, selectors, and resolvers follow the WordPress data package patterns.

Form Handling

DataForm from @wordpress/dataviews for admin forms. Valibot for API response validation. CSS Modules with camelCase exports.

REST API

Namespace: /wpappointments/v1/

All responses use a standardized envelope with pagination:

{
  "data": [...],
  "totalItems": 50,
  "totalPages": 5,
  "postsPerPage": 10,
  "currentPage": 1
}