Verifica se uma determinada transação entre contas de um determinado valor foi realizado

index.js

var verifyPayment = require('./verifyPayment');

verifyPayment('1HJBhjzp8QJrVrrFH3eZWVFtiHdTCWU82f', '1Hw1v4rqWqib351iBDx6JoFrFVX4oVu5S5', 0.004036, function(tx) {
	console.log('Pagamento identificado! depositar créditos');
})

verifyPayment.js

var request = require('request');
var proccessedTxs = [];

function verifyPayment(fromAddress, toAddress, amount, callback) {
	var interval = setInterval(function() { 
		request.get('https://blockchain.info/latestblock', null, function(err, res, body) {
			if(err) {
				return console.log(err);
			}

			body = JSON.parse(body);

			var currentHighestBlock = body.height;

			request.get('https://blockchain.info/address/'+fromAddress+'?format=json', null, function(err, res, body) {
				if(err) {
					return console.log(err);
				}

				body = JSON.parse(body);

				var confirmedTxds = 0;

				for(var x in body.txs) {
					var confirmations = currentHighestBlock - body.txs[x].block_height;

					if(confirmations >= 5 && proccessedTxs.indexOf(body.txs[x].hash) == -1) {
						if(body.txs[x].out[0].addr == toAddress && body.txs[x].inputs[0].prev_out.addr == fromAddress && body.txs[x].out[0].value/100000000 == amount) {
							++confirmedTxds;
							proccessedTxs.push(body.txs[x].hash);
							callback(body.txs[x]);
						}
					}
				}

				if(confirmedTxds > 0) {
					clearInterval(interval);
				}
			})
		})
	}, 10000);
}

module.exports = verifyPayment;