efx-api-node/src/efx.js

<img src="https://avatars3.githubusercontent.com/u/33315316?s=200&v=4" align="right" />

const bind = require('./lib/bind_api')
const defaultConfig = require('./config')
const Web3 = require('web3')
const aware = require('aware')
const BigNumber = require('bignumber.js')
BigNumber.config({ EXPONENTIAL_AT: 1e+9 })

/**
 * web3 - web3 object
 * config - config to be merged with defaultConfig
 */
module.exports = async (web3, userConfig = {}) => {
  // binds all ./api methods into a fresh object, similar to creating an instance
  let efx = bind()

  // adds key-value storage and event emitting capabilities
  aware(efx)

  // merge user config with default config
  // needed for the efx.getConfig method
  efx.config = Object.assign({}, defaultConfig, userConfig)

  // ethfinex exchange config
  const exchangeConf = await efx.getConfig()

  //user config has priority
  efx.config = Object.assign({}, defaultConfig, exchangeConf, userConfig )

  // working towards being as compatible as possible
  efx.isBrowser = typeof window !== 'undefined'

  efx.isMetaMask = false

  if (efx.isBrowser && window.web3) {
    efx.isMetaMask = window.web3.currentProvider.isMetaMask
  }

  // If no web3 is provided we will fallback to:
  // - window.web3.currentProvider object i.e. user is using MetaMask
  // - http://localhost:8545
  if (!web3) {
    // sudo make-me browser friendly
    if (efx.isBrowser && window.web3) {
      web3 = new Web3(window.web3.currentProvider)
    } else {
      web3 = new Web3(efx.config.defaultProvider)
    }
  }

  // save web3 instance int it
  efx.web3 = web3

  // REVIEW: should we actually use web3.eth.defaultAccount ?
  // see: https://github.com/MetaMask/faq/blob/master/DEVELOPERS.md#raising_hand-account-list-reflects-user-preference
  await efx.account.select(efx.config.account)

  if (!efx.get('account')) {
    console.warn('Please specify a valid account or account index')
  }

  return efx
}