TypeError: undefined is not a constructor (evaluating 'new brorand.Rand()')

[Kishanjvaghela]

I am using react-native-crypto with rn-nodeify. but got following error

Requiring module "react-native-crypto/index.js", which threw an exception: TypeError: undefined is not a constructor (evaluating 'new brorand.Rand()')

[mikhaildobs]

Hi, we are working on RN Ethereum starter and just had the same issue with import of ethereumjs-wallet lib.
Adding one line with "require("crypto")" above the import fixed the problem.
See here - https://gitlab.com/sashamihaha/rn-ethereum-starter/commit/69a96ee8bdc9dc9ee6dae887b2e77f24284e7c27#L5
Maybe that will also help you.

[claykohut]

Did you ever figure this out @Kishanjvaghela ?

[nomoreboredom]

following this as well, requiring as @Dobrokhvalov noted fixes the problem but I only see white screen

[mvayngrib]

@Kishanjvaghela does @Dobrokhvalov's fix work for you? If not, send me a link to your project, I can take a quick look.

@Dobrokhvalov maybe we should add require('crypto') to the crypto section of shim.js?
Currently it only gets run when not remotely debugging.

[claykohut]

I was just able to fix by adding the following to shim.js

global.crypto = require('crypto')
global.crypto.getRandomValues = function(byteArray) {
  for (let i = 0; i < byteArray.length; i++) {
    byteArray[i] = Math.floor(256 * Math.random());
  }
}

Before adding the getRandomValues method, the app would only work when remotely debugging

[mvayngrib]

@claykohut oof, you don't want to do that! rn-nodeify already shims getRandomValues with a secure implementation backed by either the iOS/Android native rng, or sjcl's implementation seeded with the native rng. Just make sure to import shim.js in your project, as early as possible

[claykohut]

Thanks for the heads up @mvayngrib ! Any idea why my shim.js didnt already have that in it?

I've now manually copied the shim.js you linked to over to my shim.js -- previously it looked like:

if (typeof __dirname === 'undefined') global.__dirname = '/'
if (typeof __filename === 'undefined') global.__filename = ''
if (typeof process === 'undefined') {
  global.process = require('process')
} else {
  var bProcess = require('process')
  for (var p in bProcess) {
    if (!(p in process)) {
      process[p] = bProcess[p]
    }
  }
}

process.browser = false
if (typeof Buffer === 'undefined') global.Buffer = require('buffer').Buffer

// global.location = global.location || { port: 80 }
var isDev = typeof __DEV__ === 'boolean' && __DEV__
process.env['NODE_ENV'] = isDev ? 'development' : 'production'
if (typeof localStorage !== 'undefined') {
  localStorage.debug = isDev ? '*' : ''
}

[mvayngrib]

yea, i forget when i added the crypto stuff to shim.js. rn-nodeify doesn't overwrite your shim.js, so I guess u missed out on an update. rn-nodeify should probably export the shim in a better way, e.g. recommend apps to require it via import 'rn-nodeify/shim' instead of recommending copying it over.

[dylanbathurst]

Not sure if everyone has got this working yet but I had the same problem and after messing with it for a while I got it working.

1. rm -rf node_modules
2. rm shim.js
3. npm install
4. rn-nodeify --hack --install

And it worked! A couple things to note.

1. I had hacked bignumber.js (that's required by web3.js) a while back to work with the proper crypto library, but removed the hack since rn-nodeify solves the issue.
2. When building from xcode on a simulator or device I made sure to do a hard clean of the build directory (option + shift + command + k)

I'm not 100% sure what combination of all of this worked but it's currently working for me.

[mvayngrib]

looks like this is now working for people. The crypto shim has been moved over to a more sensible place in react-native-crypto, where it's loaded automatically. If this is still an issue for someone, we'll reopen

[sreeksp]

@claykohut @mvayngrib
it shows me a blank white screen . No errors though.
this is how my shim.js looks

if (typeof __dirname === 'undefined') global.__dirname = '/'
if (typeof __filename === 'undefined') global.__filename = ''
if (typeof process === 'undefined') {
  global.process = require('process')
} else {
  const bProcess = require('process')
  for (var p in bProcess) {
    if (!(p in process)) {
      process[p] = bProcess[p]
    }
  }
}

process.browser = false
if (typeof Buffer === 'undefined') global.Buffer = require('buffer').Buffer

// global.location = global.location || { port: 80 }
const isDev = typeof __DEV__ === 'boolean' && __DEV__
process.env['NODE_ENV'] = isDev ? 'development' : 'production'
if (typeof localStorage !== 'undefined') {
  localStorage.debug = isDev ? '*' : ''
}

Am i missing anything?

[mvayngrib]

@sreeksp not enough information :) Did you check for errors both in the dev tools console and in the react-native packager's?

[ahmb84]

Hello!
I've resolved this issue by importing crypto just after shim.js
This is my app.js

import "./shim";
import crypto from "crypto";
import React from "react";
import App from "./js/App";

export default class App1 extends React.Component {
  render() {
    return <App />;
  }
}

[devonwesley]

Thanks @dylanbathurst and @ahmb84 , a combination of those 2 suggestions helped me out.