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Error Codes

Error Structure

All purchase errors follow a consistent structure for easy handling. The PurchaseError shape is defined below.

swift

struct PurchaseError: Codable {
    let code: ErrorCode    // Generated error enum
    let message: String    // Human-readable message
    let productId: String? // Related product SKU (if applicable)
    let debugMessage: String? // Raw diagnostic (e.g. StoreKit error.localizedDescription)
    let responseCode: Int? // Android QueryProduct BillingResult.responseCode
    let productIds: [String]? // Android QueryProduct requested IDs
    let productType: String? // Android BillingClient product type
    let isEmptyProductList: Bool? // Android QueryProduct returned no products
    let subResponseCodeAndroid: SubResponseCodeAndroid? // Play purchase-update detail
}

Kotlin example

data class PurchaseError(
    val code: ErrorCode,            // Generated error enum
    val message: String,            // Human-readable message
    val productId: String? = null,  // Related product SKU (if applicable)
    val debugMessage: String? = null, // Raw BillingResult.debugMessage from Google Play
    val responseCode: Int? = null,   // Android QueryProduct BillingResult.responseCode
    val productIds: List<String>? = null, // Android QueryProduct requested IDs
    val productType: String? = null, // Android BillingClient product type
    val isEmptyProductList: Boolean? = null, // Android returned no products
    val subResponseCodeAndroid: SubResponseCodeAndroid? = null // Play purchase-update detail
)

TypeScript example

interface PurchaseError {
  code: ErrorCode;        // Generated kebab-case error enum
  message: string;        // Human-readable message
  productId?: string;     // Related product SKU (if applicable)
  debugMessage?: string;  // Raw diagnostic from the billing layer (e.g. Play's BillingResult.debugMessage)
  responseCode?: number;  // Android QueryProduct BillingResult.responseCode
  productIds?: string[];  // Android QueryProduct requested IDs
  productType?: string;   // Android BillingClient product type
  isEmptyProductList?: boolean; // Android QueryProduct returned no products
  subResponseCodeAndroid?: SubResponseCodeAndroid; // Play purchase-update detail
}

Dart example

dart

class PurchaseError {
  final ErrorCode code;     // Generated error enum
  final String message;     // Human-readable message
  final String? productId;  // Related product SKU (if applicable)
  final String? debugMessage; // Raw BillingResult.debugMessage on Android
  final int? responseCode;  // Android QueryProduct BillingResult.responseCode
  final List<String>? productIds; // Android QueryProduct requested IDs
  final String? productType; // Android BillingClient product type
  final bool? isEmptyProductList; // Android returned no products
  final SubResponseCodeAndroid? subResponseCodeAndroid; // Play purchase-update detail
}

C# (MAUI) example

using OpenIap;
using OpenIap.Maui;

public sealed record PurchaseError
{
    public required ErrorCode Code { get; init; } // Error code constant
    public required string Message { get; init; } // Human-readable message
    public string? ProductId { get; init; } // Related product SKU
    public string? DebugMessage { get; init; } // Raw billing diagnostic
    public int? ResponseCode { get; init; } // Android QueryProduct responseCode
    public IReadOnlyList<string>? ProductIds { get; init; } // Android requested IDs
    public string? ProductType { get; init; } // Android BillingClient product type
    public bool? IsEmptyProductList { get; init; } // Android returned no products
    public SubResponseCodeAndroid? SubResponseCodeAndroid { get; init; } // Play purchase-update detail
}

Kotlin (KMP) example

data class PurchaseError(
    val code: ErrorCode,            // Generated error enum
    val message: String,            // Human-readable message
    val productId: String? = null,  // Related product SKU (if applicable)
    val debugMessage: String? = null, // Raw diagnostic from the underlying billing layer
    val responseCode: Int? = null,   // Android QueryProduct BillingResult.responseCode
    val productIds: List<String>? = null, // Android QueryProduct requested IDs
    val productType: String? = null, // Android BillingClient product type
    val isEmptyProductList: Boolean? = null, // Android returned no products
    val subResponseCodeAndroid: SubResponseCodeAndroid? = null // Play purchase-update detail
)

GDScript example

class PurchaseError:

	var code: ErrorCode              # Generated error enum
	var message: String              # Human-readable message
	var product_id: Variant = null   # Related product SKU (if applicable)
	var debug_message: Variant = null # Raw diagnostic from the billing layer
	var response_code: Variant = null # Android QueryProduct BillingResult.responseCode
	var product_ids: Array[String] = [] # Android QueryProduct requested IDs
	var product_type: Variant = null  # Android BillingClient product type
	var is_empty_product_list: Variant = null # Android returned no products
	var sub_response_code_android: Variant = null # SubResponseCodeAndroid when present

Common Error Codes

User Action Errors

Code	Description	Action
`UserCancelled`	User cancelled the purchase flow	No action needed, expected behavior
`UserError`	User-related error during purchase	Check user account status
`DeferredPayment`	Payment was deferred (pending family approval, etc.)	Wait for payment approval
`Interrupted`	Purchase flow was interrupted	Retry the purchase

Product Errors

Code	Description	Action
`ItemUnavailable`	Product not available in store	Check product configuration in store console
`SkuNotFound`	SKU not found in product list	Verify SKU exists in store configuration
`SkuOfferMismatch`	SKU offer ID mismatch	Check offer configuration for the SKU
`QueryProduct`	Failed to query product details	Check product IDs and retry
`AlreadyOwned`	Item already owned by user	Restore purchases to unlock content
`ItemNotOwned`	Item not owned by user	Purchase the item first
`DuplicatePurchase`	Duplicate `purchase-updated` event for the same token (Android)	Deduplicate by purchase token and ignore duplicates

User cancellation: The canonical serialized value is user-cancelled. Some wrappers still normalize legacy E_USER_CANCELLED aliases for compatibility, but new app code should compare the generated ErrorCode.UserCancelled enum value or the user-cancelled wire value.

Android diagnostics: QueryProduct errors from openiap-google 2.1.4 and later include the Google Play Billing responseCode, debugMessage, requested productIds, requested productType, and isEmptyProductList when available. Use these diagnostics to distinguish Play Console product setup issues from transient BillingClient failures. In OpenIAP 2.3.0 / openiap-google 2.3.1, purchase-update failures also carry subResponseCodeAndroid (requires Play Billing 8.0+) when Play Billing provides a more specific reason such as insufficient funds or offer ineligibility.

Network & Service Errors

Code	Description	Action
`NetworkError`	Network connection error	Check internet connection and retry
`ServiceError`	Store service error	Wait and retry, check store service status
`RemoteError`	Remote server error	Check server logs, retry request
`InitConnection`	Failed to initialize store connection	Check store service availability and retry
`ServiceDisconnected`	Store service disconnected	Reconnect to the store service
`ServiceTimeout`	Request reached the billing service timeout (Google Play 8.x+)	Retry the call after a short delay
`ConnectionClosed`	Connection to store service was closed	Reinitialize connection and retry
`IapNotAvailable`	In-app purchase service not available	Check device settings and IAP availability
`BillingUnavailable`	Billing service is unavailable	Check Google Play/App Store availability
`FeatureNotSupported`	Requested feature not supported	Check device/OS version compatibility
`SyncError`	Synchronization error with store	Retry synchronization

Validation Errors

Code	Description	Action
`PurchaseVerificationFailed`	Purchase verification failed	Check verification logic, retry validation
`PurchaseVerificationFinished`	Purchase verification already completed	Verification already completed, check records
`PurchaseVerificationFinishFailed`	Failed to finish purchase verification	Check verification state and retry
`TransactionValidationFailed`	Transaction validation failed	Verify transaction data and retry
`EmptySkuList`	Empty SKU list provided	Provide at least one SKU to query

Error Handling Examples

Error Handling Pattern

Implement error handlers that respond appropriately to each error type:

User Cancellation - Silent handling, no alerts
Product Issues - Inform user about availability
Ownership Conflicts - Trigger purchase restoration
Network Errors - Suggest retry with backoff
Unknown Errors - Generic fallback message

User Cancellation

Treat user cancellation as an expected result of the purchase flow. Do not show an error alert, retry automatically, or report it as a service failure.

import { ErrorCode } from 'react-native-iap';

function isUserCancellation(error: { code?: unknown }) {
  return error.code === ErrorCode.UserCancelled || error.code === 'user-cancelled';
}

Dart example

dart

try {
  // Call a purchase or iOS-only API.
} on PurchaseError catch (error) {
  if (error.code == ErrorCode.UserCancelled) return;
  rethrow;
}

Kotlin (KMP) example

try {
    // Call a purchase or iOS-only API.
} catch (error: PurchaseException) {
    if (error.error.code == ErrorCode.UserCancelled) return
    throw error
}

Retry Strategy

Implement retry logic for transient errors:

Note: These retry strategies are automatically handled within the OpenIAP module. You don't need to implement them manually.

Error Type	Can Retry	Strategy
NetworkError	Yes	Exponential backoff (2^n seconds)
ServiceError	Yes	Linear backoff (n * 5 seconds)
RemoteError	Yes	Fixed delay (10 seconds)
ConnectionClosed	Yes	Reinitialize and retry
SyncError	Yes	Exponential backoff
UserCancelled	No	Do not retry
AlreadyOwned	No	Restore instead
DeferredPayment	No	Wait for approval
NotPrepared	No	Initialize connection first

Platform-Specific Error Handling

iOS Error Codes

Native Code	Mapped Error	Description
0	Unknown	Unknown error
1	UserCancelled	User cancelled transaction
2	NetworkError	Network unavailable
3	ItemUnavailable	Product not available
4	ServiceError	App Store service error
5	PurchaseVerificationFailed	Purchase verification failed
6	AlreadyOwned	Product already purchased

Android example

Android Response Codes

Response Code	Mapped Error	Description
0	OK	Success
1	UserCancelled	User pressed back or cancelled
2	ServiceError	Network connection down
3	ServiceError	Billing API unavailable
4	ItemUnavailable	Requested product not available
5	DeveloperError	Invalid arguments provided
6	Unknown	Fatal error during API action
7	AlreadyOwned	Item already owned
8	ItemNotOwned	Item not owned

ErrorCode Enum (Unified)

Complete list of error codes that can be returned by the IAP library.

swift

enum OpenIapError: Error {
    case unknown
    case userCancelled
    case userError
    case itemUnavailable
    case remoteError
    case networkError
    case serviceError
    case purchaseVerificationFailed
    case purchaseVerificationFinished
    case purchaseVerificationFinishFailed
    case notPrepared
    case notEnded
    case alreadyOwned
    case developerError
    case billingResponseJsonParseError
    case deferredPayment
    case interrupted
    case iapNotAvailable
    case purchaseError
    case syncError
    case transactionValidationFailed
    case activityUnavailable
    case alreadyPrepared
    case pending
    case connectionClosed
    case initConnection
    case serviceDisconnected
    case serviceTimeout
    case queryProduct
    case skuNotFound
    case skuOfferMismatch
    case itemNotOwned
    case billingUnavailable
    case featureNotSupported
    case emptySkuList
    case duplicatePurchase
}

Kotlin example

enum class OpenIapError {
    Unknown,
    UserCancelled,
    UserError,
    ItemUnavailable,
    RemoteError,
    NetworkError,
    ServiceError,
    PurchaseVerificationFailed,
    PurchaseVerificationFinished,
    PurchaseVerificationFinishFailed,
    NotPrepared,
    NotEnded,
    AlreadyOwned,
    DeveloperError,
    BillingResponseJsonParseError,
    DeferredPayment,
    Interrupted,
    IapNotAvailable,
    PurchaseError,
    SyncError,
    TransactionValidationFailed,
    ActivityUnavailable,
    AlreadyPrepared,
    Pending,
    ConnectionClosed,
    InitConnection,
    ServiceDisconnected,
    ServiceTimeout,
    QueryProduct,
    SkuNotFound,
    SkuOfferMismatch,
    ItemNotOwned,
    BillingUnavailable,
    FeatureNotSupported,
    EmptySkuList,
    DuplicatePurchase,
}

TypeScript example

enum ErrorCode {
  Unknown = 'unknown',
  UserCancelled = 'user-cancelled',
  UserError = 'user-error',
  ItemUnavailable = 'item-unavailable',
  RemoteError = 'remote-error',
  NetworkError = 'network-error',
  ServiceError = 'service-error',
  PurchaseVerificationFailed = 'purchase-verification-failed',
  PurchaseVerificationFinished = 'purchase-verification-finished',
  PurchaseVerificationFinishFailed = 'purchase-verification-finish-failed',
  NotPrepared = 'not-prepared',
  NotEnded = 'not-ended',
  AlreadyOwned = 'already-owned',
  DeveloperError = 'developer-error',
  BillingResponseJsonParseError = 'billing-response-json-parse-error',
  DeferredPayment = 'deferred-payment',
  Interrupted = 'interrupted',
  IapNotAvailable = 'iap-not-available',
  PurchaseError = 'purchase-error',
  SyncError = 'sync-error',
  TransactionValidationFailed = 'transaction-validation-failed',
  ActivityUnavailable = 'activity-unavailable',
  AlreadyPrepared = 'already-prepared',
  Pending = 'pending',
  ConnectionClosed = 'connection-closed',
  InitConnection = 'init-connection',
  ServiceDisconnected = 'service-disconnected',
  ServiceTimeout = 'service-timeout',
  QueryProduct = 'query-product',
  SkuNotFound = 'sku-not-found',
  SkuOfferMismatch = 'sku-offer-mismatch',
  ItemNotOwned = 'item-not-owned',
  BillingUnavailable = 'billing-unavailable',
  FeatureNotSupported = 'feature-not-supported',
  EmptySkuList = 'empty-sku-list',
  DuplicatePurchase = 'duplicate-purchase',
}

Dart example

dart

enum IAPError {
  unknown,
  userCancelled,
  userError,
  itemUnavailable,
  remoteError,
  networkError,
  serviceError,
  purchaseVerificationFailed,
  purchaseVerificationFinished,
  purchaseVerificationFinishFailed,
  notPrepared,
  notEnded,
  alreadyOwned,
  developerError,
  billingResponseJsonParseError,
  deferredPayment,
  interrupted,
  iapNotAvailable,
  purchaseError,
  syncError,
  transactionValidationFailed,
  activityUnavailable,
  alreadyPrepared,
  pending,
  connectionClosed,
  initConnection,
  serviceDisconnected,
  serviceTimeout,
  queryProduct,
  skuNotFound,
  skuOfferMismatch,
  itemNotOwned,
  billingUnavailable,
  featureNotSupported,
  emptySkuList,
  duplicatePurchase,
}

C# (MAUI) example

using OpenIap;

public enum ErrorCode
{
    Unknown,
    UserCancelled,
    UserError,
    ItemUnavailable,
    RemoteError,
    NetworkError,
    ServiceError,
    PurchaseVerificationFailed,
    PurchaseVerificationFinished,
    PurchaseVerificationFinishFailed,
    NotPrepared,
    NotEnded,
    AlreadyOwned,
    DeveloperError,
    BillingResponseJsonParseError,
    DeferredPayment,
    Interrupted,
    IapNotAvailable,
    PurchaseError,
    SyncError,
    TransactionValidationFailed,
    ActivityUnavailable,
    AlreadyPrepared,
    Pending,
    ConnectionClosed,
    InitConnection,
    ServiceDisconnected,
    ServiceTimeout,
    QueryProduct,
    SkuNotFound,
    SkuOfferMismatch,
    ItemNotOwned,
    BillingUnavailable,
    FeatureNotSupported,
    EmptySkuList,
    DuplicatePurchase,
}

Kotlin (KMP) example

enum class OpenIapError {
    Unknown,
    UserCancelled,
    UserError,
    ItemUnavailable,
    RemoteError,
    NetworkError,
    ServiceError,
    PurchaseVerificationFailed,
    PurchaseVerificationFinished,
    PurchaseVerificationFinishFailed,
    NotPrepared,
    NotEnded,
    AlreadyOwned,
    DeveloperError,
    BillingResponseJsonParseError,
    DeferredPayment,
    Interrupted,
    IapNotAvailable,
    PurchaseError,
    SyncError,
    TransactionValidationFailed,
    ActivityUnavailable,
    AlreadyPrepared,
    Pending,
    ConnectionClosed,
    InitConnection,
    ServiceDisconnected,
    ServiceTimeout,
    QueryProduct,
    SkuNotFound,
    SkuOfferMismatch,
    ItemNotOwned,
    BillingUnavailable,
    FeatureNotSupported,
    EmptySkuList,
    DuplicatePurchase,
}

GDScript example

enum OpenIapError {
    UNKNOWN,
    USER_CANCELLED,
    USER_ERROR,
    ITEM_UNAVAILABLE,
    REMOTE_ERROR,
    NETWORK_ERROR,
    SERVICE_ERROR,
    PURCHASE_VERIFICATION_FAILED,
    PURCHASE_VERIFICATION_FINISHED,
    PURCHASE_VERIFICATION_FINISH_FAILED,
    NOT_PREPARED,
    NOT_ENDED,
    ALREADY_OWNED,
    DEVELOPER_ERROR,
    BILLING_RESPONSE_JSON_PARSE_ERROR,
    DEFERRED_PAYMENT,
    INTERRUPTED,
    IAP_NOT_AVAILABLE,
    PURCHASE_ERROR,
    SYNC_ERROR,
    TRANSACTION_VALIDATION_FAILED,
    ACTIVITY_UNAVAILABLE,
    ALREADY_PREPARED,
    PENDING,
    CONNECTION_CLOSED,
    INIT_CONNECTION,
    SERVICE_DISCONNECTED,
    SERVICE_TIMEOUT,
    QUERY_PRODUCT,
    SKU_NOT_FOUND,
    SKU_OFFER_MISMATCH,
    ITEM_NOT_OWNED,
    BILLING_UNAVAILABLE,
    FEATURE_NOT_SUPPORTED,
    EMPTY_SKU_LIST,
    DUPLICATE_PURCHASE,
}

Testing Error Scenarios

iOS Sandbox Testing

Test Account	Simulated Error
test.purchase.failed@example.com	PurchaseVerificationFailed
test.purchase.cancelled@example.com	UserCancelled
test.purchase.unavailable@example.com	ItemUnavailable

Android Testing Methods

Test Method	Description
License Testing	Add test accounts in Google Play Console for real purchases without charges
Internal Testing Track	Deploy to internal testers for production-like testing
Closed Testing	Test with limited group of users before production release
Test Cards (Sandbox)	Use test payment methods configured in Play Console

⚠️ Important: Static test product IDs like android.test.purchased are deprecated and no longer work. Use real product IDs with test accounts instead. See Releases page for details →

Development Testing

For development testing, consider implementing mock error generators that can simulate various error conditions without requiring actual purchases. This allows you to:

Test error handling UI flows
Verify analytics tracking
Validate retry logic
Ensure proper error recovery