index.js

import {
  NativeModules,
  NativeEventEmitter,
  DeviceEventEmitter,
  Platform,
} from "react-native";

const { RNInAppPurchase } = NativeModules;

const ERROR = {
  FETCH_PRODUCTS: "FETCH_PRODUCTS",
  PURCHASE: "PURCHASE",
  CONNECTION: "CONNECTION",
};

const addListener = (event, listener) =>
  Platform.select({
    ios: new NativeEventEmitter(RNInAppPurchase),
    android: DeviceEventEmitter,
  }).addListener(event, listener);

const removeAllListeners = (event) =>
  Platform.select({
    ios: new NativeEventEmitter(RNInAppPurchase),
    android: DeviceEventEmitter,
  }).removeAllListeners(event);

const onFetchProducts = (listener) =>
  addListener("iap:onFetchProductsSuccess", listener);

const onPurchase = (listener) => addListener("iap:onPurchaseSuccess", listener);

const onError = (listener) => {
  if (Platform.OS === "android") {
    addListener("iap:onConnectionFailure", (e) =>
      listener(Object.assign(e, { type: ERROR.CONNECTION }))
    );
  }
  addListener("iap:onFetchProductsFailure", (e) =>
    listener(Object.assign(e, { type: ERROR.FETCH_PRODUCTS }))
  );
  addListener("iap:onPurchaseFailure", (e) =>
    listener(Object.assign(e, { type: ERROR.PURCHASE }))
  );
};

const clear = () => {
  removeAllListeners("iap:onFetchProductsSuccess");
  removeAllListeners("iap:onPurchaseSuccess");
  removeAllListeners("iap:onFetchProductsFailure");
  removeAllListeners("iap:onPurchaseFailure");
  if (Platform.OS === "android") {
    removeAllListeners("iap:onConnectionFailure");
  }
};

const purchase = (productId, originalPurchaseToken) => {
  if (Platform.OS === "android") {
    RNInAppPurchase.purchase(productId, originalPurchaseToken || null);
  } else {
    RNInAppPurchase.purchase(productId);
  }
};

const restore = () => {
  if (Platform.OS === "ios") {
    RNInAppPurchase.restore(null);
  }
};

const finalize = (purchase, isConsumable) => {
  return Platform.OS === "android"
    ? RNInAppPurchase.finalize(purchase, isConsumable)
    : RNInAppPurchase.finalize(purchase);
};

export default {
  configure: RNInAppPurchase.configure,
  fetchProducts: RNInAppPurchase.fetchProducts,
  flush: RNInAppPurchase.flush,
  purchase,
  restore,
  finalize,
  onFetchProducts,
  onPurchase,
  onError,
  clear,
  ERROR,
};