better handling of ticker errors

lib/plugins.js

@@ -38,6 +38,8 @@ function plugins (settings, deviceId) {
       const cryptoConfig = configManager.scoped(cryptoCode, deviceId, settings.config)
       const rateRec = tickers[i]
 
+      if (!rateRec) return
+
       const cashInCommission = BN(1).add(BN(cryptoConfig.cashInCommission).div(100))
 
       const cashOutCommission = _.isNil(cryptoConfig.cashOutCommission)

lib/ticker.js

@@ -1,6 +1,9 @@
 const mem = require('mem')
 const configManager = require('./config-manager')
 const ph = require('./plugin-helper')
+const logger = require('./logger')
+
+const lastRate = {}
 
 const FETCH_INTERVAL = 10000
 function getRates (settings, fiatCode, cryptoCode) {
@@ -12,11 +15,21 @@ function getRates (settings, fiatCode, cryptoCode) {
     const account = settings.accounts[plugin]
     const ticker = ph.load(ph.TICKER, plugin)
 
+    const market = [cryptoCode, fiatCode].join('-')
+
     return ticker.ticker(account, fiatCode, cryptoCode)
     .then(r => ({
       rates: r.rates,
       timestamp: Date.now()
     }))
+    .then(r => {
+      lastRate[market] = r
+      return r
+    })
+    .catch(err => {
+      logger.error(err)
+      return lastRate[market]
+    })
   })
 }