draft: refactor project so it sits on top of a standalone app

zero.Web.UI/node_modules/webpack-dev-server/lib/servers/WebsocketServer.js

@@ -0,0 +1,70 @@
+'use strict';
+
+/* eslint-disable
+  class-methods-use-this
+*/
+const ws = require('ws');
+const BaseServer = require('./BaseServer');
+
+module.exports = class WebsocketServer extends BaseServer {
+  constructor(server) {
+    super(server);
+    this.wsServer = new ws.Server({
+      noServer: true,
+      path: this.server.sockPath,
+    });
+
+    this.server.listeningApp.on('upgrade', (req, sock, head) => {
+      if (!this.wsServer.shouldHandle(req)) {
+        return;
+      }
+
+      this.wsServer.handleUpgrade(req, sock, head, (connection) => {
+        this.wsServer.emit('connection', connection, req);
+      });
+    });
+
+    this.wsServer.on('error', (err) => {
+      this.server.log.error(err.message);
+    });
+
+    const noop = () => {};
+
+    setInterval(() => {
+      this.wsServer.clients.forEach((ws) => {
+        if (ws.isAlive === false) return ws.terminate();
+
+        ws.isAlive = false;
+        ws.ping(noop);
+      });
+    }, this.server.heartbeatInterval);
+  }
+
+  send(connection, message) {
+    // prevent cases where the server is trying to send data while connection is closing
+    if (connection.readyState !== 1) {
+      return;
+    }
+
+    connection.send(message);
+  }
+
+  close(connection) {
+    connection.close();
+  }
+
+  // f should be passed the resulting connection and the connection headers
+  onConnection(f) {
+    this.wsServer.on('connection', (connection, req) => {
+      connection.isAlive = true;
+      connection.on('pong', () => {
+        connection.isAlive = true;
+      });
+      f(connection, req.headers);
+    });
+  }
+
+  onConnectionClose(connection, f) {
+    connection.on('close', f);
+  }
+};