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Building a unicorn

Dmitry Semenovsky dsemenovsky

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Building a unicorn
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@dsemenovsky
dsemenovsky / confirmEtherTransaction.js
Created Jun 1, 2018
Confirm Ethereum transaction
View confirmEtherTransaction.js
function confirmEtherTransaction(txHash, confirmations = 10) {
setTimeout(async () => {
// Get current number of confirmations and compare it with sought-for value
const trxConfirmations = await getConfirmations(txHash)
console.log('Transaction with hash ' + txHash + ' has ' + trxConfirmations + ' confirmation(s)')
if (trxConfirmations >= confirmations) {
// Handle confirmation event according to your business logic
@dsemenovsky
dsemenovsky / getConfirmations.js
Created Jun 1, 2018
Get Ethereum transaction confirmations count
View getConfirmations.js
async function getConfirmations(txHash) {
try {
// Instantiate web3 with HttpProvider
const web3 = new Web3('https://rinkeby.infura.io/')
// Get transaction details
const trx = await web3.eth.getTransaction(txHash)
// Get current block number
const currentBlock = await web3.eth.getBlockNumber()
View watchTokenTransfers.js
function watchTokenTransfers() {
// Instantiate web3 with WebSocketProvider
const web3 = new Web3(new Web3.providers.WebsocketProvider('wss://rinkeby.infura.io/ws'))
// Instantiate token contract object with JSON ABI and address
const tokenContract = new web3.eth.Contract(
TOKEN_ABI, process.env.TOKEN_CONTRACT_ADDRESS,
(error, result) => { if (error) console.log(error) }
)
View watchEtherTransfers.js
function watchEtherTransfers() {
// Instantiate web3 with WebSocket provider
const web3 = new Web3(new Web3.providers.WebsocketProvider('wss://rinkeby.infura.io/ws'))
// Instantiate subscription object
const subscription = web3.eth.subscribe('pendingTransactions')
// Subscribe to pending transactions
subscription.subscribe((error, result) => {
if (error) console.log(error)
View db.rake
# lib/tasks/db.rake
namespace :db do
desc "Dumps the database to db/APP_NAME.dump"
task :dump => :environment do
cmd = nil
with_config do |app, host, db, user|
cmd = "pg_dump --host #{host} --username #{user} --verbose --clean --no-owner --no-acl --format=c #{db} > #{Rails.root}/db/#{app}.dump"
end
puts cmd