fix: build markets requests and caching

lib/exchange.js

@@ -50,19 +50,26 @@ function active (settings, cryptoCode) {
 }
 
 function getMarkets () {
-  const filterExchanges = _.filter(it => it.class === 'exchange')
+  const filterExchanges = _.filter(it => it.class === 'exchange' && !it.dev && it.code !== 'no-exchange')
   const availableExchanges = _.map(it => it.code, filterExchanges(accounts.ACCOUNT_LIST))
 
-  return _.reduce(
-    (acc, value) =>
-    Promise.all([acc, ccxt.getMarkets(value, ALL_CRYPTOS)])
-      .then(([a, markets]) => Promise.resolve({
-        ...a,
-        [value]: markets
-      })),
-    Promise.resolve({}),
-    availableExchanges
-  )
+  const fetchMarketForExchange = exchange =>
+    ccxt.getMarkets(exchange, ALL_CRYPTOS)
+      .then(markets => ({ exchange, markets }))
+      .catch(error => ({
+        exchange,
+        markets: [],
+        error: error.message
+      }))
+
+  const transformToObject = _.reduce((acc, { exchange, markets }) => ({
+    ...acc,
+    [exchange]: markets
+  }), {})
+
+  const promises = _.map(fetchMarketForExchange, availableExchanges)
+  return Promise.all(promises)
+    .then(transformToObject)
 }
 
 module.exports = {