WP Freemius Client — Overview

A lite, UI-free Freemius SDK for Foxe Labs WordPress plugins. It handles license activation, deactivation, update delivery, and addon listing by talking to the Freemius API directly.

The library deliberately ships no admin screens — host plugins build their own UI and call into this library for the underlying logic.

What it does

• License activation / deactivation against the Freemius API.
• Update delivery — hooks into WordPress' standard update pipeline for premium builds.
• Addon listing with 24-hour caching and a checkout URL per addon.
• Signed API requests using the FS / FSP header-signing scheme.

What it does not do

• No admin notices, settings screens, activation modals, or opt-in flows.
• No nonce / capability checks — host plugins MUST do that before forwarding form input to activate() / deactivate().

Architecture

Small dependency-injection container wired up by FoxeLabs\Freemius\Freemius:

src/
├── Freemius.php              # Container + entry point
├── Api/                      # HTTP client, signing, factory
├── Contracts/                # ServiceInterface, ApiClientInterface, CacheInterface
├── Data/                     # Plugin, Activation, ApiKeys value objects
├── Storage/                  # ActivationRepository, TransientCache
├── Services/                 # License, Update, Addon
├── Support/                  # SiteIdentity
└── Exceptions/               # FreemiusException

Each service receives its collaborators by constructor injection, so they can be unit-tested without WordPress in the loop. Hook registration happens inside boot() — instantiating the container has no side effects.