v12.0.0 - initial commit

packages/server/lib/ticker.js

@@ -0,0 +1,73 @@
+const { utils: coinUtils } = require('@lamassu/coins')
+const _ = require('lodash/fp')
+const mem = require('mem')
+
+const configManager = require('./new-config-manager')
+const logger = require('./logger')
+const lastRate = {}
+
+const ccxt = require('./plugins/ticker/ccxt')
+const mockTicker = require('./plugins/ticker/mock-ticker')
+const bitpay = require('./plugins/ticker/bitpay')
+
+const FETCH_INTERVAL = 58000
+
+const PEGGED_FIAT_CURRENCIES = { NAD: 'ZAR' }
+
+const getFallbackTicker = ticker =>
+  _.difference(['bitpay', 'kraken', 'bitstamp'], [ticker])[0]
+
+const hasRatesOrReject = emsg => r =>
+  _.get(['rates'], r) ? r : Promise.reject(new Error(emsg))
+
+const get1 = (market, fiatCode, cryptoCode, ticker, emsg) =>
+  buildTicker(fiatCode, cryptoCode, ticker)
+    .then(hasRatesOrReject(emsg))
+    .then(({ rates }) => {
+      return (lastRate[market] = { rates, timestamp: Date.now() })
+    })
+
+const _getRates = (settings, fiatCode, cryptoCode) =>
+  Promise.resolve().then(() => {
+    const ticker = configManager.getWalletSettings(
+      cryptoCode,
+      settings.config,
+    ).ticker
+    const market = [cryptoCode, fiatCode].join('-')
+    const fallbackTicker = getFallbackTicker(ticker)
+    const emsg = fallbackTicker
+      ? 'Failed to get rates with configured ticker, trying fallback'
+      : 'Failed to get ticker rates'
+    return get1(market, fiatCode, cryptoCode, ticker, emsg)
+      .catch(err => {
+        logger.error(err)
+        return fallbackTicker
+          ? get1(
+              market,
+              fiatCode,
+              cryptoCode,
+              fallbackTicker,
+              'Failed to get rates with fallback ticker',
+            )
+          : lastRate[market]
+      })
+      .then(hasRatesOrReject('Failed to get ticker rates'))
+  })
+
+function buildTicker(fiatCode, cryptoCode, tickerName) {
+  fiatCode = _.defaultTo(fiatCode, _.get([fiatCode], PEGGED_FIAT_CURRENCIES))
+  cryptoCode = coinUtils.getEquivalentCode(cryptoCode)
+
+  if (tickerName === 'bitpay') return bitpay.ticker(fiatCode, cryptoCode)
+  if (tickerName === 'mock-ticker')
+    return mockTicker.ticker(fiatCode, cryptoCode)
+  return ccxt.ticker(fiatCode, cryptoCode, tickerName)
+}
+
+const getRates = mem(_getRates, {
+  maxAge: FETCH_INTERVAL,
+  cacheKey: (settings, fiatCode, cryptoCode) =>
+    JSON.stringify([fiatCode, cryptoCode]),
+})
+
+module.exports = { getRates }