Install the Mesh SDK in React Native

npm install @offline-protocol/mesh-sdk@0.31.0

cd ios && pod install

<key>NSBluetoothAlwaysUsageDescription</key>
<string>This app uses Bluetooth to communicate with nearby devices</string>

<key>NSBluetoothPeripheralUsageDescription</key>
<string>This app uses Bluetooth to communicate with nearby devices</string>

<!-- Required for reliable BLE operation. Without these, iOS can throttle or stop
     BLE scanning and advertising, and CoreBluetooth state restoration will not work. -->
<key>UIBackgroundModes</key>
<array>
    <string>bluetooth-central</string>
    <string>bluetooth-peripheral</string>
</array>

<!-- BLE: Android 11 and below -->
<uses-permission android:name="android.permission.BLUETOOTH" android:maxSdkVersion="30" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" android:maxSdkVersion="30" />

<!-- BLE: Android 12+ -->
<uses-permission android:name="android.permission.BLUETOOTH_SCAN"
    android:usesPermissionFlags="neverForLocation" />
<uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" />
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />

<!-- Wi-Fi Direct and the relay (declared by the SDK from v0.28.0) -->
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
<uses-permission android:name="android.permission.NEARBY_WIFI_DEVICES"
    android:usesPermissionFlags="neverForLocation" />
<uses-permission android:name="android.permission.INTERNET" />

<!-- The Wi-Fi network peer stream (declared by the SDK from v0.29.0) -->
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE" />

<!-- Background mesh operation -->
<uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
<uses-permission android:name="android.permission.FOREGROUND_SERVICE_CONNECTED_DEVICE" />
<uses-permission android:name="android.permission.WAKE_LOCK" />

<uses-feature android:name="android.hardware.bluetooth_le" android:required="false" />

<!-- BLE scanning on Android 11 and below -->
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" android:maxSdkVersion="30" />

<!-- Android 13+: without this the mesh keep-alive notification is silently suppressed -->
<uses-permission android:name="android.permission.POST_NOTIFICATIONS" />

import { PermissionsAndroid, Platform, type Permission } from 'react-native';

export async function requestMeshPermissions(): Promise<boolean> {
  if (Platform.OS !== 'android') return true;

  const permissions: Permission[] = [];
  const apiLevel = Platform.Version as number;

  if (apiLevel >= 31) {
    permissions.push(
      PermissionsAndroid.PERMISSIONS.BLUETOOTH_SCAN,
      PermissionsAndroid.PERMISSIONS.BLUETOOTH_CONNECT,
      PermissionsAndroid.PERMISSIONS.BLUETOOTH_ADVERTISE,
    );
  } else {
    permissions.push(
      PermissionsAndroid.PERMISSIONS.ACCESS_FINE_LOCATION,
    );
  }

  if (apiLevel >= 33) {
    permissions.push(PermissionsAndroid.PERMISSIONS.POST_NOTIFICATIONS);
  }

  const results = await PermissionsAndroid.requestMultiple(permissions);
  return Object.values(results).every(
    (r) => r === PermissionsAndroid.RESULTS.GRANTED,
  );
}

if (!(await protocol.isBluetoothEnabled())) {
  await protocol.requestEnableBluetooth();  // Android only; returns false on iOS
}

<uses-permission android:name="android.permission.ACCESS_LOCAL_NETWORK" />

<key>NSBonjourServices</key>
<array>
    <string>_offlineprotocol._tcp</string>
</array>
<key>NSLocalNetworkUsageDescription</key>
<string>Finds and talks to nearby devices running this app</string>

import { PermissionsAndroid, Platform } from 'react-native';

export async function requestWifiDirectPermission(): Promise<boolean> {
  if (Platform.OS !== 'android') return true;
  const permission = (Platform.Version as number) >= 33
    ? PermissionsAndroid.PERMISSIONS.NEARBY_WIFI_DEVICES
    : PermissionsAndroid.PERMISSIONS.ACCESS_FINE_LOCATION;
  const result = await PermissionsAndroid.request(permission);
  return result === PermissionsAndroid.RESULTS.GRANTED;
}

<meta-data android:name="com.offlineprotocol.MESH_WAKE_ENABLED" android:value="true" />
<!-- Optional; default 60, clamped to 10-300 -->
<meta-data android:name="com.offlineprotocol.MESH_WAKE_TIMEOUT_SECONDS" android:value="60" />

import { AppRegistry } from 'react-native';
import { OfflineProtocol, registerMeshWakeTask } from '@offline-protocol/mesh-sdk';
import App from './App';
import { name as appName } from './app.json';
import { getLiveProtocol, setLiveProtocol, loadSavedConfig, persistMessage, loadRelayConfig } from './mesh-state';

registerMeshWakeTask(async () => {
  if (getLiveProtocol()) return;
  const config = await loadSavedConfig();
  if (!config) return;
  const protocol = new OfflineProtocol(config);
  protocol.on('message_received', persistMessage);
  setLiveProtocol(protocol);
  try {
    await protocol.start();
    const relay = await loadRelayConfig();
    if (relay) await protocol.enableTransport('internet', relay);
  } catch (error) {
    setLiveProtocol(null);
    await protocol.stop();
    await protocol.destroy();
    throw error;
  }
});
AppRegistry.registerComponent(appName, () => App);