Masamune Purchase

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Masamune Purchase

Overview

masamune_purchase is the base package for in-app purchase functionality in Masamune apps. It provides:

• Abstract purchase controllers and adapters
• Purchase product definitions
• Functions actions for backend validation
• Purchase models for persisting user entitlements
• Delegate interfaces for purchase lifecycle events

Note: This is the base package. You'll also need concrete implementations:

• masamune_purchase_mobile for Google Play / App Store (in-app purchases)
• masamune_purchase_stripe for Stripe-based web payments

Usage

Installation

flutter pub add masamune_purchase
flutter pub add masamune_purchase_mobile  # For mobile IAP

Concrete Implementations

This base package provides the interfaces. Use concrete implementations:

Mobile IAP (masamune_purchase_mobile)

• Provides MobilePurchaseMasamuneAdapter
• Integrates with Google Play Billing and App Store
• Supports consumable, non-consumable, and subscription products
• See masamune_purchase_mobile package for setup

Stripe Payments (masamune_purchase_stripe)

• Provides StripePurchaseMasamuneAdapter
• Web-based payment flows
• See masamune_purchase_stripe package for setup

Runtime Adapter (Testing)

• RuntimePurchaseMasamuneAdapter - Mock purchases for testing

Purchase Product Definitions

Define your products using PurchaseProduct:

Subscription:

PurchaseProduct.subscription(
  productId: "premium_monthly",
  title: LocalizedValue("Premium Monthly"),
  description: LocalizedValue("Unlock all features"),
  period: PurchaseSubscriptionPeriod.month,
)

Non-Consumable (one-time purchase):

PurchaseProduct.nonConsumable(
  productId: "lifetime_unlock",
  title: LocalizedValue("Lifetime Access"),
  description: LocalizedValue("Permanent access to all features"),
)

Consumable (coins, credits, etc.):

PurchaseProduct.consumable(
  productId: "coin_pack_100",
  title: LocalizedValue("100 Coins"),
  description: LocalizedValue("Get 100 coins"),
  amount: 100,
)

Purchase Models

The package includes Masamune models for persisting purchase data:

PurchaseUserModel: Store user-level entitlements

final purchaseUser = ref.app.model(
  PurchaseUserModel.document(userId: currentUserId),
)..load();

// Check if user has premium access
final hasPremium = purchaseUser.value?.hasPremiumAccess ?? false;

PurchaseSubscriptionModel: Store subscription state

final subscription = ref.app.model(
  PurchaseSubscriptionModel.document(
    userId: currentUserId,
    subscriptionId: "premium_monthly",
  ),
)..load();

// Check subscription status
final isActive = subscription.value?.isActive ?? false;
final expiresAt = subscription.value?.expiresAt;

Functions Actions

The package provides Functions actions for backend validation:

Android:

• AndroidConsumablePurchaseFunctionsAction
• AndroidNonConsumablePurchaseFunctionsAction
• AndroidSubscriptionPurchaseFunctionsAction

iOS:

• IosConsumablePurchaseFunctionsAction
• IosNonConsumablePurchaseFunctionsAction
• IosSubscriptionPurchaseFunctionsAction

These actions send purchase receipts to your backend for validation.

Purchase Delegates

Define custom logic for purchase lifecycle events:

ConsumablePurchaseDelegate:

class CoinsDelegate extends ConsumablePurchaseDelegate {
  @override
  Future<void> onDelivered({
    required PurchaseProduct product,
    required double amount,
  }) async {
    // Credit coins to user account
    await userRepository.addCoins(userId, amount.toInt());
  }
}

SubscriptionPurchaseDelegate:

class PremiumDelegate extends SubscriptionPurchaseDelegate {
  @override
  Future<void> onActivated({required PurchaseProduct product}) async {
    // Grant premium access
    await userRepository.setPremiumStatus(userId, true);
  }
  
  @override
  Future<void> onExpired({required PurchaseProduct product}) async {
    // Revoke premium access
    await userRepository.setPremiumStatus(userId, false);
  }
}

For Implementation Details

See the implementation-specific packages:

• masamune_purchase_mobile - Mobile IAP (Google Play / App Store) setup and usage
• masamune_purchase_stripe - Stripe payment integration

GitHub Sponsors

Sponsors are always welcome. Thank you for your support!

https://github.com/sponsors/mathrunet