spv btc fees fallback

main.js

@@ -464,8 +464,6 @@ app.on('quit', (event) => {
 	}
 });
 
-app.commandLine.appendSwitch('ignore-certificate-errors'); // dirty hack
-
 function formatBytes(bytes, decimals) {
   if (bytes === 0) {
     return '0 Bytes';

routes/shepherd.js

@@ -103,6 +103,7 @@ shepherd = require('./shepherd/electrum/createtx-multi.js')(shepherd);
 shepherd = require('./shepherd/electrum/interest.js')(shepherd);
 shepherd = require('./shepherd/electrum/listunspent.js')(shepherd);
 shepherd = require('./shepherd/electrum/estimate.js')(shepherd);
+shepherd = require('./shepherd/electrum/btcFees.js')(shepherd);
 
 // dex
 shepherd = require('./shepherd/dex/coind.js')(shepherd);

routes/shepherd/electrum/btcFees.js

@@ -0,0 +1,115 @@
+const request = require('request');
+const Promise = require('bluebird');
+
+let btcFeeBlocks = [];
+
+for (let i = 0; i < 25; i++) {
+  btcFeeBlocks.push(i);
+}
+
+const checkTimestamp = (dateToCheck) => {
+  const currentEpochTime = new Date(Date.now()) / 1000;
+  const secondsElapsed = Number(currentEpochTime) - Number(dateToCheck);
+
+  return Math.floor(secondsElapsed);
+}
+
+const getRandomIntInclusive = (min, max) => {
+  min = Math.ceil(min);
+  max = Math.floor(max);
+
+  return Math.floor(Math.random() * (max - min + 1)) + min; // the maximum is inclusive and the minimum is inclusive
+}
+
+let btcFees = {
+  recommended: {},
+  all: {},
+  electrum: {},
+  lastUpdated: null,
+};
+
+const BTC_FEES_MIN_ELAPSED_TIME = 120;
+
+module.exports = (shepherd) => {
+  shepherd.get('/electrum/btcfees', (req, res, next) => {
+    if (shepherd.checkToken(req.query.token)) {
+      if (checkTimestamp(btcFees.lastUpdated) > BTC_FEES_MIN_ELAPSED_TIME) {
+        const _randomServer = shepherd.electrumServers.btc.serverList[getRandomIntInclusive(0, shepherd.electrumServers.btc.serverList.length - 1)].split(':');
+        const ecl = new shepherd.electrumJSCore(_randomServer[1], _randomServer[0], 'tcp');
+        let _btcFeeEstimates = [];
+
+        console.log(`btc fees server ${_randomServer.join(':')}`);
+
+        ecl.connect();
+        Promise.all(btcFeeBlocks.map((coin, index) => {
+          return new Promise((resolve, reject) => {
+            ecl.blockchainEstimatefee(index + 1)
+            .then((json) => {
+              resolve(true);
+
+              if (json > 0) {
+                _btcFeeEstimates.push(Math.floor((json / 1024) * 100000000));
+              }
+            });
+          });
+        }))
+        .then(result => {
+          ecl.close();
+
+          if (result &&
+              result.length) {
+            btcFees.electrum = _btcFeeEstimates;
+          } else {
+            btcFees.electrum = 'error';
+          }
+
+          let options = {
+            url: `https://bitcoinfees.earn.com/api/v1/fees/recommended`,
+            method: 'GET',
+          };
+
+          // send back body on both success and error
+          // this bit replicates iguana core's behaviour
+          request(options, (error, response, body) => {
+            if (response &&
+                response.statusCode &&
+                response.statusCode === 200) {
+              try {
+                const _parsedBody = JSON.parse(body);
+                btcFees.lastUpdated = Math.floor(Date.now() / 1000);
+                btcFees.recommended = _parsedBody;
+              } catch (e) {
+                shepherd.log('unable to retrieve BTC fees / recommended', true);
+              }
+            } else {
+              shepherd.log('unable to retrieve BTC fees / recommended', true);
+            }
+
+            res.end(JSON.stringify({
+              msg: 'success',
+              result: btcFees,
+            }));
+          });
+        });
+      } else {
+        console.log(`btcfees, use cache`);
+
+        const successObj = {
+          msg: 'success',
+          result: btcFees,
+        };
+
+        res.end(JSON.stringify(successObj));
+      }
+    } else {
+      const errorObj = {
+        msg: 'error',
+        result: 'unauthorized access',
+      };
+
+      res.end(JSON.stringify(errorObj));
+    }
+  });
+
+  return shepherd;
+};