This documentation is intended to solve dependancies issues of react-native when using NEM2-sdk, but is not limited to NEM2-sdk package. This method is appliable for any package that is using nodeJS built-in library, if you know what you are doing.

Since react-native will check dependancies during compile time, package existence checking is not possible during run time.

Steps to workaround:

Create a react-native project and change to the project directory

Please follow the instructions to create a react-native project here.

Installing dependancy with yarn is not recommended, as I am not able to make it work when installing with yarn. If someone kind of happen to tested it out, please kindly let me know the result. Many Thanks :)

Create new file named rn-cli.config.js, put in the code as below:

var extraNodeModules = {
  crypto: require.resolve('crypto-browserify'),
  fs: require.resolve('react-native-fs'),
  http: require.resolve('stream-http'),
  https: require.resolve('https-browserify'),
  process: require.resolve('process/browser.js'),
  stream: require.resolve('readable-stream'),
  tls: require.resolve('tls-browserify'),
  net: require.resolve('net-browserify'),
  util: require.resolve('util/util.js'),
  punycode: require.resolve('punycode/'),
  url: require.resolve('react-native-url'),
  querystring: require.resolve('querystring-es3/'),
  zlib: require.resolve('react-zlib-js'),
  path: require.resolve('react-native-path'),
  vm: require.resolve('vm-browserify')
};

module.exports = {
  resolver: {
    extraNodeModules: extraNodeModules
  }
};

What it does is resolve the packages that is built-in in nodejs to another packages

put in all required the dependancy in package.json, under dependancies:

"assert": "^1.4.1",
"asyncstorage-down": "^4.1.2",
"browserify-zlib": "^0.1.4",
"buffer": "^5.2.1",
"crypto-browserify": "^3.12.0",
"events": "^3.0.0",
"https-browserify": "^1.0.0",
"nem2-sdk": "^0.10.1",
"net-browserify": "^0.2.4",
"process": "^0.11.0",
"punycode": "^1.2.4",
"querystring-es3": "^0.2.1",
"react-native-fs": "^2.13.3",
"react-native-level-fs": "^3.0.0",
"react-native-path": "0.0.5",
"react-native-url": "0.0.2",
"react-zlib-js": "^1.0.4",
"readable-stream": "^1.0.33",
"stream-browserify": "^1.0.0",
"stream-http": "^3.0.0",
"tls-browserify": "^0.2.2",
"url": "^0.11.0",
"vm-browserify": "^1.1.0"

install all the dependancies

npm install

add packager config file into app.json, include the config file which is the rn-cli.config.js file created above

add the code below in the app.json, inside the expo object

"packagerOpts": {
    "projectRoots": "",
    "config": "rn-cli.config.js"
},

run the command below

npm i --save-dev tradle/rn-nodeify

for linux

./node_modules/.bin/rn-nodeify --hack --install

for windows

.\node_modules\.bin\rn-nodeify --hack --install

after running the command, a shim.js file will be created

insert this code at the top of App.js

import './shim.js'

run the following command with terminal or cmd, if the package react-native-crypto exist :

Please remove it using yarn if the package is installed with yarn

npm uninstall react-native-crypto

npm uninstall react-native-randombytes

we need to remove react-native-crypto and react-native-randombytes as we are not using it, we are using crypto-browserify and react-native-randombytes throwing error

just import the NEM2-sdk with require

const nem2 = require('nem2-sdk');

now you can use the NEM2-sdk without error, happy coding~!!

This workaround is not 100% tested, some issues might happen when using the NEM2-sdk with react-native. Please feel free to file issues.

You can check out the js nem2-sdk here.

NEM2 documentation and tutorials can be found here.