React Nativeでトランザクションを送信する方法

/**
 * Metro configuration for React Native
 * https://github.com/facebook/react-native
 *
 * @format
 */

module.exports = {
// ここのresolverを追加する
  resolver: {
    extraNodeModules: {
      crypto: require.resolve('crypto-browserify'),
      stream: require.resolve('readable-stream'),
    },
  },
// ここはデフォであります。
  transformer: {
    getTransformOptions: async () => ({
      transform: {
        experimentalImportSupport: false,
        inlineRequires: true,
      },
    }),
  },
};

/**
 * @format
 */
// ここに追加
import './shim.js';
// 以下はデフォルト
import {AppRegistry} from 'react-native';
import App from './App';
import {name as appName} from './app.json';

AppRegistry.registerComponent(appName, () => App);

/**
 * Sample React Native App
 * https://github.com/facebook/react-native
 *
 * @format
 */

import React from 'react';
import {
  Alert,
  Button,
  SafeAreaView,
  ScrollView,
  StatusBar,
  useColorScheme,
} from 'react-native';

import {Colors, Header} from 'react-native/Libraries/NewAppScreen';

import {
  RepositoryFactoryHttp,
  Account,
  Address,
  TransferTransaction,
  Deadline,
  PlainMessage,
  UInt64,
} from 'symbol-sdk';

// ここの秘密鍵とアドレスは各自調整が必須
const AlicePrivateKey =
  'B82E003F3DAF29C1E55C39553327B8E178D820396C8A6144AA71329EF391D0EB';
const bobAddress = 'TBH3OVV3AFONJZSYOMUILGERPNYY77AISF54C4Q';

const example = async (): Promise<void> => {
  // Network information
// ネットワークも動いていないものを使うとネットワークエラーになるので使えるやつを使いましょう。
  const nodeUrl = 'https://vmi834332.contaboserver.net:3001';
  const repositoryFactory = new RepositoryFactoryHttp(nodeUrl);
  const epochAdjustment = await repositoryFactory
    .getEpochAdjustment()
    .toPromise();
  const networkType = await repositoryFactory.getNetworkType().toPromise();
  const networkGenerationHash = await repositoryFactory
    .getGenerationHash()
    .toPromise();
  const recipientAddress = Address.createFromRawAddress(bobAddress);
  const transferTransaction = TransferTransaction.create(
    Deadline.create(epochAdjustment!), // 有効期限
    recipientAddress, // 受取人のアドレス
    [], // 送信するモザイクとその数量
    PlainMessage.create('This is a test message'), // メッセージ
    networkType!, // ネットワークタイプ
    UInt64.fromUint(2000000), // 手数料
  );

  const account = Account.createFromPrivateKey(AlicePrivateKey, networkType!);
  const signedTransaction = account.sign(
    transferTransaction,
    networkGenerationHash!,
  );
  console.log(signedTransaction.hash, 'hash');
  console.log('--------------------------------');
  console.log(signedTransaction.payload, 'payload');
  const transactionRepository = repositoryFactory.createTransactionRepository();
  const response = await transactionRepository
    .announce(signedTransaction)
    .toPromise();
  console.log(response);
};

function App(): JSX.Element {
  const isDarkMode = useColorScheme() === 'dark';

  const backgroundStyle = {
    backgroundColor: isDarkMode ? Colors.darker : Colors.lighter,
  };

  return (
    <SafeAreaView style={backgroundStyle}>
      <StatusBar
        barStyle={isDarkMode ? 'light-content' : 'dark-content'}
        backgroundColor={backgroundStyle.backgroundColor}
      />
      <ScrollView
        contentInsetAdjustmentBehavior="automatic"
        style={backgroundStyle}>
        <Header />
        <Button
          title="Press me"
          onPress={() => Alert.alert('Simple Button pressed')}
        />
        <Button
          title="押してみそ"
          onPress={() =>
            example()
              .then()
              .catch(err => console.log(err))
          }
        />
      </ScrollView>
    </SafeAreaView>
  );
}

export default App;