nifty-wallet/app/scripts/inpage.js

/*global Web3*/
cleanContextForImports()
require('web3/dist/web3.min.js')
const log = require('loglevel')
const LocalMessageDuplexStream = require('post-message-stream')
const setupDappAutoReload = require('./lib/auto-reload.js')
const MetamaskInpageProvider = require('./lib/inpage-provider.js')
restoreContextAfterImports()

log.setDefaultLevel(process.env.METAMASK_DEBUG ? 'debug' : 'warn')

//
// setup plugin communication
//

// setup background connection
var metamaskStream = new LocalMessageDuplexStream({
  name: 'nifty-inpage',
  target: 'nifty-contentscript',
})

// compose the inpage provider
var inpageProvider = new MetamaskInpageProvider(metamaskStream)

//
// setup web3
//

var web3 = new Web3(inpageProvider)
web3.setProvider = function () {
  log.debug('Nifty Wallet - overrode web3.setProvider')
}
log.debug('Nifty Wallet - injected web3')

setupDappAutoReload(web3, inpageProvider.publicConfigStore)

// export global web3, with usage-detection and deprecation warning

/* TODO: Uncomment this area once auto-reload.js has been deprecated:
let hasBeenWarned = false
global.web3 = new Proxy(web3, {
  get: (_web3, key) => {
    // show warning once on web3 access
    if (!hasBeenWarned && key !== 'currentProvider') {
      console.warn('Nifty Wallet: web3 will be deprecated in the near future in favor of the ethereumProvider \nhttps://github.com/MetaMask/faq/blob/master/detecting_metamask.md#web3-deprecation')
      hasBeenWarned = true
    }
    // return value normally
    return _web3[key]
  },
  set: (_web3, key, value) => {
    // set value normally
    _web3[key] = value
  },
})
*/

// set web3 defaultAccount
inpageProvider.publicConfigStore.subscribe(function (state) {
  web3.eth.defaultAccount = state.selectedAddress
})

// need to make sure we aren't affected by overlapping namespaces
// and that we dont affect the app with our namespace
// mostly a fix for web3's BigNumber if AMD's "define" is defined...
var __define

/**
 * Caches reference to global define object and deletes it to
 * avoid conflicts with other global define objects, such as
 * AMD's define function
 */
function cleanContextForImports () {
  __define = global.define
  try {
    global.define = undefined
  } catch (_) {
    console.warn('Nifty Wallet - global.define could not be deleted.')
  }
}

/**
 * Restores global define object from cached reference
 */
function restoreContextAfterImports () {
  try {
    global.define = __define
  } catch (_) {
    console.warn('Nifty Wallet - global.define could not be overwritten.')
  }
}