jssuttles/Instructions

## app.js
'use strict';

//var Murmurhash   = require('murmurhash-native').murmurHash128x86

nw.Window.get().showDevTools();
var realFs = require('fs');
var fse = require('fs-extra');
fse.createOutputStream = require('create-output-stream');
fse.gracefulify(realFs);
var fs = require('bluebird').promisifyAll(fse);
var murmur   = require('murmurhash-native/stream');
var Transform = require('stream').Transform;
var createOutputStream = require('create-output-stream');
global.mainURI = '';
global.jsFolder = '';
global.modelsFolder = '';
global.vendorFolder = '';

class HashTransform extends Transform {
  constructor() {
    super();
    this.hasher = murmur.createHash('murmurHash128x86');
    // the following works
    //this.hasher = murmur.createHash('murmurHash128x86', {seed: 42, endianness: 'LE'});
    this.createdHash = '';
  }

  _transform(chunk, enc, cb) {
    var buffer = (Buffer.isBuffer(chunk)) ? chunk : new Buffer(chunk, enc);
    this.hasher.update(buffer);
    this.push(chunk);
    cb();
  }

  _flush(cb) {
    this.createdHash = this.hasher.digest('base64');
    cb();
  }
}


function copyAndChecksum(source, target) {
  return new Promise(function(resolve, reject) {
    var rd = fs.createReadStream(source);
    var wr = fs.createOutputStream(target);
    var doneCalled = false;
    rd.on('error', function(err) {
      done(err);
    });
    wr.on('error', function(err) {
      done(err);
    });
    wr.on('close', function() {
      done();
    });
    var hash = new HashTransform();
    rd.pipe(hash).pipe(wr);

    function done(err) {
      if (!doneCalled) {
        if (err) {
          reject(err);
        } else {
          resolve(hash.createdHash);
        }
        doneCalled = true;
      }
    }
  });
}

copyAndChecksum('./package.json', './package2.json')
.then(function(hash) {
  console.log(hash);

  // this stuff I was thinking would work based on
  // murmurHash(data{String}, encoding|output_type[, callback])
  // var stuff = Murmurhash('assafasfasfasddd', 'hex').substr(0, 10).toUpperCase();
  // console.log(stuff);
  process.exit(0);
});

## index.html
<!DOCTYPE html>
<html>
    <head>
        <title>Simple APP</title>
    </head>
    <body>
        <script src="app.js"></script>
    </body>
</html>

## Instructions
To run this:
sudo npm i -g nw@0.15.4-sdk

Navigate to folder where this is saved:
nw .

This should pop up the chrome devtools and display the error in the console.
I attempted this on a Mac.

## package.json
{
    "name": "simple-app",
    "main": "index.html",
    "dependencies": {
      "bluebird": "^3.4.1",
      "create-output-stream": "0.0.1",
      "fs-extra": "^0.30.0",
      "murmurhash-native": "^3.2.0"
    }
}
	'use strict';

	//var Murmurhash = require('murmurhash-native').murmurHash128x86

	nw.Window.get().showDevTools();
	var realFs = require('fs');
	var fse = require('fs-extra');
	fse.createOutputStream = require('create-output-stream');
	fse.gracefulify(realFs);
	var fs = require('bluebird').promisifyAll(fse);
	var murmur = require('murmurhash-native/stream');
	var Transform = require('stream').Transform;
	var createOutputStream = require('create-output-stream');
	global.mainURI = '';
	global.jsFolder = '';
	global.modelsFolder = '';
	global.vendorFolder = '';

	class HashTransform extends Transform {
	constructor() {
	super();
	this.hasher = murmur.createHash('murmurHash128x86');
	// the following works
	//this.hasher = murmur.createHash('murmurHash128x86', {seed: 42, endianness: 'LE'});
	this.createdHash = '';
	}

	_transform(chunk, enc, cb) {
	var buffer = (Buffer.isBuffer(chunk)) ? chunk : new Buffer(chunk, enc);
	this.hasher.update(buffer);
	this.push(chunk);
	cb();
	}

	_flush(cb) {
	this.createdHash = this.hasher.digest('base64');
	cb();
	}
	}


	function copyAndChecksum(source, target) {
	return new Promise(function(resolve, reject) {
	var rd = fs.createReadStream(source);
	var wr = fs.createOutputStream(target);
	var doneCalled = false;
	rd.on('error', function(err) {
	done(err);
	});
	wr.on('error', function(err) {
	done(err);
	});
	wr.on('close', function() {
	done();
	});
	var hash = new HashTransform();
	rd.pipe(hash).pipe(wr);

	function done(err) {
	if (!doneCalled) {
	if (err) {
	reject(err);
	} else {
	resolve(hash.createdHash);
	}
	doneCalled = true;
	}
	}
	});
	}

	copyAndChecksum('./package.json', './package2.json')
	.then(function(hash) {
	console.log(hash);

	// this stuff I was thinking would work based on
	// murmurHash(data{String}, encoding\|output_type[, callback])
	// var stuff = Murmurhash('assafasfasfasddd', 'hex').substr(0, 10).toUpperCase();
	// console.log(stuff);
	process.exit(0);
	});
	<!DOCTYPE html>
	<html>
	<head>
	<title>Simple APP</title>
	</head>
	<body>
	<script src="app.js"></script>
	</body>
	</html>
	To run this:
	sudo npm i -g nw@0.15.4-sdk

	Navigate to folder where this is saved:
	nw .

	This should pop up the chrome devtools and display the error in the console.
	I attempted this on a Mac.
	{
	"name": "simple-app",
	"main": "index.html",
	"dependencies": {
	"bluebird": "^3.4.1",
	"create-output-stream": "0.0.1",
	"fs-extra": "^0.30.0",
	"murmurhash-native": "^3.2.0"
	}
	}