Resolve error :"Unable to resolve module `crypto` in \\azure-mobile-apps-client\\node_modules\\node-uuid\\uuid.js''

I met issue "Unable to resolve module `crypto` in \\azure-mobile-apps-client\\node_modules\\node-uuid\\uuid.js'" when I developed an App using React Native and Azure Mobile App Service.

The Azure Mobile App Service uses the crypto module in "uuid.js" such as "require('crypto').randomBytes", because crypto is a core Node JS module, and the React Native packager can’t package it along with app’s Javascript bundle, so it throws a runtime error: Unable to resolve module 'crypto'.

I did a research on google.com, and fount out this article "Using Core Node JS Modules in React Native Apps". Based on this article, I came out a solution to resolve this problem as below.

1. npm install -g browserify
2.  Create a file crypto-in.js that imports the crypto module and simply exports it: 

   var crypto=require("crypto");
   module.exports=crypto;

3.  Create a standalone Javascript bundle crypto.js using browserify in NPM commandline window.
   

   browserify crypto-in.js -o crypto.js

4.   After the changes, crypto.js should look something like this:

    var crypto;
   
   // Some 21,500 lines of polyfills..
   
   },{"indexof":100}],153:[function(reqq,module,exports){
   
   crypto = reqq("crypto");
   
   },{"crypto":56}]},{},[153]);
   
   module.exports = crypto;

5. In “\\node_modules\\azure-mobile-apps-client\\node_modules\\node-uuid\\uuid.js”,update the code as below:

     function setupNode() {
   

   // Node.js crypto-based RNG - http://nodejs.org/docs/v0.6.2/api/crypto.html

   // Moderately fast, high quality

   if ('function' === typeof require) {

   try {

   //var _rb = require('crypto').randomBytes;

   var _rb =require('./crypto').randomBytes;

   
   

   _nodeRNG = _rng = _rb && function() {return _rb(16);};

   _rng();

   } catch(e) {}

   }

   }

After I done that, the App can be compiled successfully.