rn-nodeify

Run after npm install and you can use node core modules and npm modules that use them in your React Native app.

What is solves

If your project has no non-React-Native dependencies, you don't need this module, and you should just check out './shims.js' for the core node modules to use individually.

However, with bigger projects that don't reimplement every wheel from scratch, somewhere in your dependency tree, something uses a core node module. I found myself building this because in my React Native app, I wanted to use bitcoinjs-lib, levelup, bittorrent-dht, and lots of fun crypto. If that sounds like you, keep reading.

What it does

rn-nodeify --install installs shims for core node modules, see './shims.js' for the current mappings. It recurses down node_modules and modifies all the package.json's in there to add/update the browser and react-native fields. It sounds scary because it is. However, it does work.

rn-nodeify --hack Now that you're scared, I should also mention that there are some package-specific hacks (see './pkg-hacks.js'), for when the React Native packager choked on something that Webpack and Browserify swallowed.

If you're looking for a saner approach, check out ReactNativify. I haven't tested it myself, but I think philikon will be happy to help.

Usage

rn-nodeify <options>

Options

--install     install node core shims (default: install all), fix the "browser"
              and "react-native" fields in the package.json's of dependencies
--hack        hack individual packages that are known to make the React Native packager choke
--yarn        use yarn instead of npm

Examples

# install all shims and run package-specific hacks
rn-nodeify --install --hack

# install specific shims
rn-nodeify --install "fs,dgram,process,path,console"

# install specific shims and hack
rn-nodeify --install "fs,dgram,process,path,console" --hack

It is recommended to add this command to the "postinstall" script in your project's package.json

"scripts": {
  "start": "node node_modules/react-native/local-cli/cli.js start",
  "postinstall": "rn-nodeify --install fs,dgram,process,path,console --hack"
}

rn-nodeify will create a shim.js file in your project root directory. The first line in index.ios.js / index.android.js should be to import it (NOT require it!)

import './shim'

If you are using the crypto shim, you will need to manually uncomment the line to require('crypto') in shim.js, this is because as of react-native 0.49, dynamically requiring a library is no longer allowed.

Some shims may require linking libraries, be sure to run react-native link after installing new shims if you run into problems.

Example Apps / Workflows

• the react-native-crypto package has an example workflow for using crypto in a React Native app
• this example React Native app shows how you can use levelup in React Native

Example Workflow

copied from react-native-crypto

1. Install and shim

npm i --save react-native-crypto
# install peer deps
npm i --save react-native-randombytes
react-native link react-native-randombytes
# install latest rn-nodeify
npm i --save-dev rn-nodeify@latest
# install node core shims and recursively hack package.json files
# in ./node_modules to add/update the "browser"/"react-native" field with relevant mappings
./node_modules/.bin/rn-nodeify --hack --install

2. rn-nodeify will create a shim.js in the project root directory

// index.ios.js or index.android.js
// make sure you use `import` and not `require`!
import './shim.js'
// ...the rest of your code
import crypto from 'crypto'
// use crypto
console.log(crypto.randomBytes(32).toString('hex'))

Please note...

• rn-nodeify won't work with modules that are added using npm link.
• modules that contain a .babelrc will cause problems with the latest react-native version (0.20 at this time), remove them after installation (rm node_modules/*/.babelrc)
• when installing a package from git, the postinstall hook isn't triggered, run it manually instead (npm run postinstall)
• restart the react-native packager after installing a module!
• removing the packager cache helps as well sometimes (rm -fr $TMPDIR/react-*)
• use npm@3. npm@5 has some issues that cause node_modules to disappear. See:
  • tradle#42
  • infinitered/ignite#1101
  • npm/npm#16839