@react-native-module/randombytes/lib/es/index.js

implementation of randomBytes for React Native

import { Buffer } from 'buffer';
import { randomBytesWithoutNativeModule } from './randomBytesWithoutNativeModule.js';

function randomBytes(size, callback) {
    try {
        const RNRandomBytes = require('react-native').NativeModules.RNRandomBytes;
        if (!callback) {
            return RNRandomBytes.randomBytesSync(size);
        }
        RNRandomBytes.randomBytes(size, (err, base64String) => {
            if (err != null) {
                callback(err, null);
            }
            else {
                callback(null, Buffer.from(base64String, 'base64'));
            }
        });
    }
    catch (error) {
        if (error) {
            if (['randomBytesSync', 'randomBytes'].some(v => error.message.includes(`Cannot read property '${v}' of null`))) {
                if (callback != null) {
                    return randomBytesWithoutNativeModule(size, callback);
                }
                else {
                    return randomBytesWithoutNativeModule(size);
                }
            }
        }
        if (callback) {
            callback(error, null);
        }
        else {
            throw error;
        }
    }
}

export { randomBytes as default };