implement socks5 proxy measurement

helpers.js

@@ -1,8 +1,24 @@
+const sortProxyServers = (proxyList) => {
+    return proxyList.sort((proxyServer1, proxyServer2) => {
+        if (proxyServer1 && proxyServer1.timeToFetch && proxyServer2 && proxyServer2.timeToFetch) {
+            return proxyServer1.timeToFetch > proxyServer2.timeToFetch ? 1 : -1;
+        }
+    });
+}
+
+const selectBestProxies = (proxyList) => {
+    return proxyList;
+}
+
+const cleanProxyServers = (proxyList) => {
+    return proxyList.filter(proxyServer => proxyServer && proxyServer.timeToFetch);
+}
+
 const convertProxyListToString = (proxyList) => {
     if (Array.isArray(proxyList)){
         let result = '';
         proxyList.forEach(proxyServer => {
-            result += `[${proxyServer.timeToFetch}]` + proxyServer.address + '\r\n';
+            result += `${proxyServer.address}\r\n`;
         });
         return result;
     }
@@ -11,4 +27,15 @@ const convertProxyListToString = (proxyList) => {
     return '';
 }
 
-exports.convertProxyListToString = convertProxyListToString;
+const timeoutPromise = (timeout) => {
+    return new Promise((resolve, reject) => {
+        setTimeout(() => { reject('Timeout') }, timeout);
+    });
+}
+
+
+exports.sortProxyServers = sortProxyServers;
+exports.selectBestProxies = selectBestProxies;
+exports.cleanProxyServers = cleanProxyServers;
+exports.convertProxyListToString = convertProxyListToString;
+exports.timeoutPromise = timeoutPromise;