Update to newer express/socketIO connections.

lib/api.js

@@ -1,6 +1,7 @@
 "use strict";
 const express = require('express');        // call express
 const app = express();                 // define our app using express
+const server = require('http').createServer(app);
 const cluster = require('cluster');
 const async = require("async");
 const debug = require("debug")("api");
@@ -12,12 +13,11 @@ const crypto = require('crypto');
 const cors = require('cors');
 const zmq = require('zmq');
 const sock = zmq.socket('sub');
+const io = require('socket.io')(server);
 
 let addressBase58Prefix = cnUtil.address_decode(new Buffer(global.config.pool.address));
 let threadName = "";
 let workerList = [];
-let server;
-let io;
 
 if (cluster.isMaster) {
     threadName = "(Master) ";
@@ -40,6 +40,7 @@ app.use(cors());
 app.use(bodyParser.urlencoded({extended: false}));
 app.use(bodyParser.json());
 
+
 if (cluster.isMaster) {
     let numWorkers = require('os').cpus().length;
     console.log('Master cluster setting up ' + numWorkers + ' workers...');
@@ -60,10 +61,7 @@ if (cluster.isMaster) {
         workerList.push(worker);
     });
 } else {
-    server = app.listen(8001, function () {
-        console.log('Process ' + process.pid + ' is listening to all incoming requests');
-    });
-    io = require('socket.io')(server);
+    server.listen(8001);
     // Init the ZMQ listeners here.
     sock.connect('tcp://127.0.0.1:3000');
     sock.connect('tcp://127.0.0.1:3001');