initial commit

manager-service/app.js

@@ -0,0 +1,164 @@
+const express = require('express');
+const { createProxyMiddleware } = require('http-proxy-middleware');
+const { WebSocketServer } = require('ws');
+const axios = require('axios');
+const { env } = require('process');
+
+const DATABASE_SERVICE_URL = env.DATABASE_SERVICE_URL;
+const FRONTEND_SERVICE_URL = env.FRONTEND_SERVICE_URL;
+const UPLOADER_SERVICE_URL = env.UPLOADER_SERVICE_URL;
+
+
+
+class Machine {
+  constructor(username, address) {
+    this.username = username;
+    this.address = address;
+    this.cache = null;
+    this.lastPingTime = null;
+  }
+
+  async ping() {
+    try {
+      const response = await axios.get(`http://${this.address}:5000/`);
+      this.cache = response.data;
+      this.lastPingTime = Date.now();
+    } catch (error) {
+      console.error(`Failed to ping machine ${this.username}: ${error.message}`);
+    }
+  }
+
+  getCachedResponse() {
+    return this.cache;
+  }
+}
+
+// Application setup
+const app = express();
+app.use(express.json());
+
+const machines = new Map();
+
+// Load machines from database on startup
+(async () => {
+  try {
+    const { data } = await axios.get('http://database-service/machines'); // Replace with our database endpoint
+    data.forEach(({ username, machineAddress }) => {
+      const machine = new Machine(username, machineAddress);
+      machines.set(username, machine);
+      machine.ping(); // Initial ping to populate cache
+    });
+    console.log('Loaded machines from database.');
+  } catch (error) {
+    console.error('Failed to load machines from database:', error.message);
+  }
+})();
+
+// Register a new user and their machine
+app.post('/register', async (req, res) => {
+  const { username, machineAddress } = req.body;
+
+  if (!username || !machineAddress) {
+    return res.status(400).json({ error: 'Username and machineAddress are required' });
+  }
+
+  const machine = new Machine(username, machineAddress);
+  throw new Error('need to register machine in database');
+  // register machine in db asap and await success
+  machines.set(username, machine);
+  await machine.ping();
+  res.json({ message: `User ${username} registered with address ${machineAddress}` });
+});
+
+// HTTP proxy for dynamic routing
+app.use('/:username/:path/*', async (req, res, next) => { //ensure this will work with all paths
+  //update to use gateway signature or jwt
+  const username = req.params.username;
+  const machine = machines.get(username);
+
+  if (!machine) {
+    return res.status(404).json({ error: 'User not found' });
+  }
+
+  const targetPort = req.params.path === ('upload' || 'file' || 'reserved') ? 8080 : 5000; // 3 paths that hit sync agent, rest hit bsnake
+  const proxy = createProxyMiddleware({
+    target: `http://${machine.address}:${targetPort}`,
+    changeOrigin: true,
+    pathRewrite: { [`^/${username}`]: '' }, // remove username from path before forwarding
+    ws: true,
+    onProxyReq: () => {
+      console.log(`Proxying request to ${machine.address}:${targetPort}`);
+    },
+  });
+
+  proxy(req, res, next);
+});
+
+// External route proxying, update to use wildcards for mapping to other microservices
+const externalRoutes = {
+  'login': 'frontend_service_url',
+  'signup': 'database_service_url',
+  'signin': 'database_service_url',
+  'upload': 'uploader_service_url',
+};
+
+Object.entries(externalRoutes).forEach(([route, target]) => {
+  app.use(`/${route}`, createProxyMiddleware({
+    target: target,
+    changeOrigin: true,
+    pathRewrite: { [`^/${route}`]: '' }, // see if path needs to be rewritten
+  }));
+});
+
+// WebSocket server for forwarding connections
+const wss = new WebSocketServer({ noServer: true });
+
+wss.on('connection', (ws, req) => {
+  const username = req.url.split('/')[1];
+  const machine = machines.get(username);
+
+  if (!machine) {
+    ws.close();
+    console.error(`WebSocket connection failed: User ${username} not found`);
+    return;
+  }
+
+  const target = `ws://${machine.address}:8080`;
+  const proxySocket = new WebSocket(target);
+
+  proxySocket.on('open', () => {
+    console.log(`Connected to WebSocket for user ${username}`);
+  });
+
+  proxySocket.on('message', (data) => {
+    ws.send(data);
+  });
+
+  proxySocket.on('close', () => {
+    ws.close();
+  });
+
+  proxySocket.on('error', (error) => {
+    console.error(`WebSocket error: ${error}`);
+    ws.close();
+  });
+
+  ws.on('message', (data) => {
+    proxySocket.send(data);
+  });
+
+  ws.on('close', () => {
+    proxySocket.close();
+  });
+});
+
+// Integrate WebSocket server with the HTTP server
+const server = app.listen(3000, () => {
+  console.log('Reverse proxy server running on http://localhost:3000');
+});
+
+server.on('upgrade', (req, socket, head) => {
+  wss.handleUpgrade(req, socket, head, (ws) => {
+    wss.emit('connection', ws, req);
+  });
+});