lamassu-server/lib/protocol/api/api.js
2014-04-10 12:09:29 +02:00

145 lines
5.1 KiB
JavaScript

'use strict';
require('date-utils');
//var async = require('async');
var winston = require('winston');
var logger = new (winston.Logger)({transports:[new (winston.transports.Console)()]});
var path = require('path');
var _transferExchange;
var _tickerExchange;
var _tradeExchange;
var _rates = {};
var _config;
var _commission;
var _config;
var SATOSHI_FACTOR = Math.pow(10, 8);
exports.ticker = require('./ticker');
exports.trade = require('./trade');
exports.send = require('./send');
exports.balance = require('./balance');
exports._tradeExchange = null;
exports._transferExchange = null;
exports.findExchange = function (name) {
var exchange;
try {
exchange = require('lamassu-' + name);
} catch (err) {
if (!err.message.match(/Cannot find module/)) throw err;
exchange = require(path.join(path.dirname(__dirname), 'exchanges', name));
}
return exchange;
};
exports.findTicker = function (name) {
var exchange = exports.findExchange(name);
return exchange.ticker || exchange;
};
exports.findTrader = function (name) {
var exchange = exports.findExchange(name);
return exchange.trader || exchange;
};
exports.findWallet = function (name) {
var exchange = exports.findExchange(name);
return exchange.wallet || exchange;
};
exports.triggerBalance = function triggerBalance() {
this.balance.triggerBalance();
};
exports.init = function(config) {
_config = config;
if (config.settings.lowBalanceMargin < 1) {
throw new Error('`settings.lowBalanceMargin` has to be >= 1');
}
var tickerExchangeCode = config.plugins.current.ticker;
var tickerExchangeConfig = config.plugins.settings[tickerExchangeCode] || {};
tickerExchangeConfig.currency = config.settings.currency;
_tickerExchange = exports.findTicker(tickerExchangeCode).factory(tickerExchangeConfig);
var tradeExchangeCode = config.plugins.current.trade;
if (tradeExchangeCode) {
var tradeExchangeConfig = config.plugins.settings[tradeExchangeCode];
_tradeExchange = exports.findTrader(tradeExchangeCode).factory(tradeExchangeConfig);
}
var transferExchangeCode = config.plugins.current.transfer;
var transferExchangeConfig = config.plugins.settings[transferExchangeCode];
_commission = config.settings.commission;
_transferExchange = exports.findWallet(transferExchangeCode).factory(transferExchangeConfig);
var doRequestTradeExchange = _tradeExchange && tradeExchangeCode !== transferExchangeCode;
exports._tradeExchange = _tradeExchange;
exports._transferExchange = _transferExchange;
exports.ticker.init(config, exports, _tickerExchange);
exports.trade.init(config, exports, _tradeExchange, exports.ticker);
exports.send.init(config, exports, _transferExchange, exports.ticker);
exports.balance.init(config, exports, _transferExchange,
doRequestTradeExchange ? _tradeExchange : null);
};
/**
* return fiat balance
*
* in input to this function, balance has the following parameters...
*
* balance.transferBalance - in satoshis
* balance.tradeBalance - in USD
*
* Have added conversion here, but this really needs to be thought through, lamassu-bitstamp should perhaps
* return balance in satoshis
*/
exports.fiatBalance = function(rate, balance, transferSatoshis, tradeFiat, callback) {
if (!rate || !balance) return 0;
// The rate is actually our commission times real rate.
rate = _commission * rate;
// `lowBalanceMargin` is our safety net. It's a number > 1, and we divide
// all our balances by it to provide a safety margin.
var lowBalanceMargin = _config.settings.lowBalanceMargin;
// `balance.transferBalance` is the balance of our transfer account (the one
// we use to send Bitcoins to clients). `transferSatoshis` is the number
// of satoshis we're expected to send for this transaction. By subtracting
// them, we get `adjustedTransferBalance`, amount of satoshis we'll have
// after the transaction.
var adjustedTransferBalance = balance.transferBalance - transferSatoshis;
// Since `adjustedTransferBalance` is in Satoshis, we need to turn it into
// Bitcoins and then fiat to learn how much fiat currency we can exchange.
//
// Unit validity proof: [ $ ] = [ (B * 10^8) / 10^8 * $/B ]
// [ $ ] = [ B * $/B ]
// [ $ ] = [ $ ]
var fiatTransferBalance = ((adjustedTransferBalance / SATOSHI_FACTOR) * rate) / lowBalanceMargin;
// If this server is also configured to trade received fiat for Bitcoins,
// we also need to calculate if we have enough funds on our trade exchange.
if (balance.tradeBalance === null) return fiatTransferBalance;
var tradeBalance = balance.tradeBalance;
// We need to secure `tradeFiat` (amount of fiat in this transaction) and
// enough fiat to cover our trading queue (trades aren't executed immediately).
var adjustedFiat = tradeFiat + exports.trade.queueFiatBalance(rate);
// So we subtract `adjustedFiat` from `tradeBalance` and again, apply
// `lowBalanceMargin`.
var fiatTradeBalance = (tradeBalance - adjustedFiat) / lowBalanceMargin;
// And we return the smallest number.
return Math.min(fiatTransferBalance, fiatTradeBalance);
};