flutter_windows_iap #

A Flutter plugin that exposes Microsoft Store in-app purchase APIs for Windows — no bundled UI.
Fetch add-on products, initiate purchases, verify licenses, and resolve One Store purchase/collection IDs — then build your own paywall and entitlement logic.

Main highlight — native Microsoft Store integration #

Built on Windows.Services.Store (StoreContext) so your Flutter Windows app can use the same add-on catalog, purchase flow, and license checks as a native UWP/WinUI app — Consumable, Durable, and UnmanagedConsumable add-ons, including subscriptions configured as durable products in Partner Center.

Platform	Windows (Microsoft Store / MSIX packaged app)
Dart	`>=3.7.0` `<4.0.0`
Flutter	`>=3.16.0`
Version	0.0.1
Channel	`com.moontechnolabs.flutter_windows_iap`
License	MIT

Features #

Feature	Description
Product catalog	Load add-on metadata (title, description, price, kind) from the Microsoft Store by Store ID
Purchase flow	Trigger the system purchase UI via `RequestPurchaseAsync`
License checks	Verify whether the user owns a specific add-on or any active add-on
Add-on licenses	Read full license map (`isActive`, expiration, SKU, offer token)
One Store IDs	Resolve `purchaseId`, `collectionId`, and OAuth token for server-side validation
No bundled UI	Data APIs only — you own the widgets and paywall

Install #

dependencies:
  flutter_windows_iap: ^0.0.1

flutter pub add flutter_windows_iap

import 'package:flutter_windows_iap/flutter_windows_iap.dart';

Configure Microsoft Store #

This plugin talks to the Microsoft Store at runtime. Your app must be MSIX-packaged and associated with a Store listing. Unpackaged debug builds will not receive valid Store responses.

1. Partner Center — create add-ons #

Open Partner Center → your app → Monetization → Add-ons.
Create one or more add-ons (Consumable, Durable, or Unmanaged Consumable).
Copy each add-on’s Store ID. You pass this string to every API that accepts a storeId.

Add-on type in Partner Center	`productKind` you may see	Typical use
Consumable	`Consumable`	Coins, credits, one-time use
Durable	`Durable`	Permanent unlock, non-expiring subscription SKU
Unmanaged consumable	`UnmanagedConsumable`	Consumables you track on your own server

Subscription add-ons are often configured with ProductKind Durable in the Store API. The plugin queries Consumable, Durable, and UnmanagedConsumable when loading products.

2. Package identity #

Your MSIX package identity (name, publisher, version) must match the app registered in Partner Center. Use tools such as msix or Visual Studio packaging to produce a build you can sideload or submit to the Store.

3. Azure AD / One Store (optional — for `getPurchaseId`) #

Server-side purchase validation requires OAuth credentials from Azure AD:

Field	Required	Why
`clientId`	Yes	Azure AD application (client) ID
`clientSecret`	Yes	Client secret for the app registration
`tenantId`	Yes	Azure AD tenant that owns the app
`resource`	No	OAuth resource for One Store B2B token (default: `https://onestore.microsoft.com`)
`collectionsResource`	No	OAuth resource for collections token (default: `https://onestore.microsoft.com/b2b/keys/create/collections`)

Register your app in Azure Portal, grant it access to the Microsoft Store commerce APIs, and pass credentials via OneStoreConfig.

4. Testing #

Store sandbox: Use a Microsoft account enrolled in Partner Center’s sandbox testers.
Sideloaded MSIX: Install a signed package whose identity matches Partner Center before calling purchase APIs.
Logs: Native code writes debug logs to %LocalAppData%\flutter_windows_iap_example\iap_log.txt when running the example app.

Quick start #

import 'package:flutter/services.dart';
import 'package:flutter_windows_iap/flutter_windows_iap.dart';

Future<void> purchaseAddon() async {
  final iap = FlutterWindowsIap();

  // Store ID from Partner Center → Monetization → Add-ons
  const storeId = 'StoreId';

  // 1. Load product info (title, price, whether user already owns it)
  final products = await iap.getProducts(storeId);
  if (products.isEmpty) return;

  // 2. Start purchase (opens Microsoft Store UI)
  final status = await iap.makePurchase(storeId);

  // 3. Verify entitlement
  final owns = await iap.checkPurchase(storeId: storeId);
}

Usage #

Create one instance of FlutterWindowsIap and reuse it for the app lifetime.

final iap = FlutterWindowsIap();

1. Get products (`getProducts`) #

Loads Store metadata for a single add-on Store ID.

final List<Product> products = await iap.getProducts('StoreId');

Parameter	Type	Required	What to pass	Why
`storeId`	`String`	Yes	Add-on Store ID from Partner Center	Identifies the SKU in `GetStoreProductsAsync`

Returns: Future<List<Product>> — usually one item when the ID is valid; empty list when nothing is found.

Throws: PlatformException when the Store returns an extended error (misconfigured product, network failure, app not associated with Store, etc.).

Field	Type	Description
`title`	`String?`	Localized product title from the Store
`description`	`String?`	Localized description
`price`	`String?`	Formatted price string (e.g. `$4.99`, `$9.99 per month`)
`inCollection`	`bool?`	`true` if the signed-in user already owns this add-on
`productKind`	`String?`	Store kind: `Consumable`, `Durable`, or `UnmanagedConsumable`
`storeId`	`String?`	Echo of the Store ID

Example — display in UI:

for (final p in products) {
print('${p.title} — ${p.price} (${p.productKind})');
if (p.inCollection == true) print('Already owned');
}

2. Make purchase (`makePurchase`) #

Opens the Microsoft Store purchase dialog for the given add-on.

final StorePurchaseStatus? status = await iap.makePurchase('StoreId');

Parameter	Type	Required	What to pass	Why
`storeId`	`String`	Yes	Same Store ID used in `getProducts`	Passed to `RequestPurchaseAsync`

Returns: Future<StorePurchaseStatus?> — see enum below. Returns null for an unrecognized status code.

Throws: PlatformException when ExtendedError is not S_OK (e.g. product not configured — HRESULT 0x803f6107).

Status	Meaning	Typical next step
`StorePurchaseStatus.succeeded`	User completed purchase	Unlock content; call `checkPurchase`
`StorePurchaseStatus.alreadyPurchased`	User already owns it	Treat as entitled
`StorePurchaseStatus.notPurchased`	User cancelled or did not buy	Keep paywall
`StorePurchaseStatus.networkError`	Network issue	Retry later
`StorePurchaseStatus.serverError`	Store server error	Retry later

switch (await iap.makePurchase(storeId)) {
case StorePurchaseStatus.succeeded:
case StorePurchaseStatus.alreadyPurchased:
// grant access
break;
case StorePurchaseStatus.notPurchased:
// user declined
break;
case StorePurchaseStatus.networkError:
case StorePurchaseStatus.serverError:
// show error, retry
break;
default:
break;
}

3. Check purchase (`checkPurchase`) #

Checks whether the current user has an active add-on license. Uses GetAppLicenseAsync and inspects add-on licenses.

final bool owns = await iap.checkPurchase(storeId: 'StoreId');

Parameter	Type	Required	What to pass	Why
`storeId`	`String`	No (default `''`)	Specific add-on Store ID, or empty string	Controls which license is checked — see rules below

Returns: Future<bool>

`storeId` value	Returns `true` when…	Returns `false` when…
Non-empty	That add-on’s license exists and `IsActive == true`	ID not found, inactive, or app license inactive
Empty (`''`)	Any add-on license has `IsActive == true`	No active add-ons, or app license inactive

If the app license itself is not active (AppLicense.IsActive == false), this method always returns false.

Use this on app start, after purchase, and when restoring entitlements:

// Premium feature for one SKU
if (await iap.checkPurchase(storeId: premiumStoreId)) {
showPremiumContent();
}

// Any paid add-on (e.g. “has anything unlocked?”)
if (await iap.checkPurchase()) {
showPaidTier();
}

4. Add-on licenses (`getAddonLicenses`) #

Returns the full license map for all add-ons the user has ever acquired.

final Map<String, StoreLicense> licenses = await iap.getAddonLicenses();

| Parameter | None |

Returns: Future<Map<String, StoreLicense>> — keys are add-on Store IDs; values are license objects.

`StoreLicense` field	Type	Description
`isActive`	`bool?`	Whether the license is currently valid
`skuStoreId`	`String?`	SKU Store ID
`inAppOfferToken`	`String?`	Offer token for promotions / trials
`expirationDate`	`num?`	Raw Windows `DateTime` tick count

Helper:

final expiry = license.getExpirationDate(); // DateTime? — converted from Store ticks

Use when you need expiration dates, offer tokens, or a full entitlement snapshot:

for (final entry in licenses.entries) {
print('${entry.key}: active=${entry.value.isActive}, '
'expires=${entry.value.getExpirationDate()}');
}

5. Purchase & collection IDs (`getPurchaseId`) #

Resolves Microsoft Store customer identifiers for server-side purchase and collections validation (One Store commerce API).

final Map<String, String> ids = await iap.getPurchaseId(
'UserId',
config: const OneStoreConfig(
clientId: 'ClientId',
clientSecret: 'ClientSecret',
tenantId: 'TenantId',
),
);

Parameter	Type	Required	What to pass	Why
`userId`	`String`	Yes	A stable, anonymous ID you assign per user (not PII)	Passed to `GetCustomerPurchaseIdAsync` / `GetCustomerCollectionsIdAsync`
`config`	`OneStoreConfig?`	Yes (credentials required)	Azure AD OAuth settings	Acquires tokens for Store API calls

Returns: Future<Map<String, String>>

Key	Description
`purchaseId`	Customer purchase ID for purchase validation APIs
`collectionId`	Customer collections ID for entitlement queries
`azureToken`	One Store B2B OAuth access token (use promptly; short-lived)

If native code returns no map, Dart fills 'NA' for each key. On failure, expect PlatformException with codes such as invalid_oauth_config, oauth_token_failed, or oauth_collections_token_failed.

Security: Never ship clientSecret in client code for production. Prefer a backend that holds secrets and returns tokens or validated entitlements to the app.

// Send to your backend — do not log secrets or tokens in release builds
await http.post(
Uri.parse('https://your-api.com/validate-purchase'),
body: {
'userId': userId,
'purchaseId': ids['purchaseId']!,
'collectionId': ids['collectionId']!,
},
);

API reference #