cosmostat has working drive health dashboard

files/vizz/docker/web/node_server/server.js

@@ -0,0 +1,153 @@
+// server.js
+const http   = require('http');
+const express = require('express');
+const { createClient } = require('redis');
+const { Server } = require('socket.io');
+const fetch  = require('node-fetch');   // npm i node-fetch@2
+const fs     = require('fs');
+const yaml   = require('js-yaml');      // npm i js-yaml
+const path   = require('path');
+
+const app    = express();
+const server = http.createServer(app);
+const io     = new Server(server);
+
+/* --------------------------------------------------------------------- */
+/* ---------- 1. Load the YAML configuration file ---------------------- */
+/* --------------------------------------------------------------------- */
+let config = {};
+try {
+  const filePath = '/app/cosmostat_settings.yaml';
+  const file     = fs.readFileSync(filePath, 'utf8');
+  config = yaml.load(file);
+} catch (e) {
+  console.error('Failed to load config.yaml:', e);
+  process.exit(1);
+}
+const API_PORT   = config.custom_api_port   || 5000;   // fallback to 5000
+const API_HOST   = config.api_bind_ip   || '192.168.37.1'; // fallback IP
+const API_BASE   = `http://${API_HOST}:${API_PORT}`;
+console.log('API URL:', API_BASE);
+
+/* --------------------------------------------------------------------- */
+/* ---------- 2. Socket.io -------------------------------------------- */
+/* --------------------------------------------------------------------- */
+io.on('connection', async socket => {
+  console.log('client connected:', socket.id);
+
+  /* -------------  send cached client_summary  ------------- */
+  if (clientSummaryCache.last) {
+    socket.emit('client_summary', clientSummaryCache.last);
+    console.log('sent cached client_summary to', socket.id);
+  }
+
+  /* ----------------------------------------------------------------- */
+  /* Call the external API every time a client connects                */
+  /* ----------------------------------------------------------------- */
+  try {
+    const resp = await fetch(`${API_BASE}/start_timer`, { method: 'GET' });
+    const data = await resp.json();
+    console.log('API responded to connect:', data);
+  } catch (err) {
+    console.error('Failed to hit start_timer endpoint:', err);
+  }
+
+  /* ----------------------------------------------------------------- */
+  /* Listen for tableRendered event from the client                    */
+  /* ----------------------------------------------------------------- */
+  socket.on('tableRendered', async () => {
+    console.log('Client reported table rendered - starting timer');
+    try {
+      const resp = await fetch(`${API_BASE}/start_timer`, { method: 'GET' });
+      const text = await resp.text();
+      console.log('Timer endpoint responded:', text);
+    } catch (err) {
+      console.error('Failed to hit start_timer:', err);
+    }
+  });
+});
+
+/* --------------------------------------------------------------------- */
+/* ---------- 3. Serve static files ----------------------------------- */
+/* --------------------------------------------------------------------- */
+app.use(express.static('public'));
+
+/* --------------------------------------------------------------------- */
+/* ---------- 4. Redis subscriber ------------------------------------- */
+/* --------------------------------------------------------------------- */
+const redisClient = createClient({
+  url:      'redis://192.168.37.1:6379',
+  socket: { keepAlive: 60000, // 60 s TCP keep-alive
+            reconnectStrategy: attempts => Math.min(attempts * 100, 3000) } // back-off
+});
+redisClient.on('error', err => console.error('Redis error', err));
+
+/* --- local cache for client_summary -------------------------------- */
+const clientSummaryCache = {};   // { last: <payload> }
+
+/* --------------------------------------------------------------------- */
+(async () => {
+  await redisClient.connect();
+  const sub = redisClient.duplicate();
+  await sub.connect();
+
+  /* --------------------------------------------------------------------- */
+  /* Helper that re-subscribes to a channel (and re-sends the handler)     */
+  /* --------------------------------------------------------------------- */
+  async function safeSubscribe(channel, handler) {
+    try {
+      await sub.subscribe(channel, handler);
+      console.log(`Subscribed to ${channel}`);
+    } catch (e) {
+      console.error(`Failed to subscribe to ${channel}`, e);
+    }
+  }
+
+  /* --------------------------------------------------------------------- */
+  /* Subscribe to all required channels                                   */
+  /* --------------------------------------------------------------------- */
+  await safeSubscribe('host_metrics',   (msg) => forward('host_metrics',   msg));
+  await safeSubscribe('client_summary', (msg) => forward('client_summary', msg));
+
+  /* --------------------------------------------------------------------- */
+  /* Forward messages to Socket.io                                         */
+  /* --------------------------------------------------------------------- */
+  function forward(channel, message) {
+    try {
+      const payload = JSON.parse(message);
+
+      /* -----  update cache on client_summary  ----- */
+      if (channel === 'client_summary') {
+        clientSummaryCache.last = payload;
+      }
+
+      io.emit(channel, payload);
+    } catch (e) {
+      console.error(`Failed to parse message from ${channel}`, e);
+    }
+  }
+
+  /* --------------------------------------------------------------------- */
+  /* Re-subscribe automatically when the Redis connection reconnects     */
+  /* --------------------------------------------------------------------- */
+  sub.on('reconnecting', () => console.log('Redis reconnecting…'));
+  sub.on('ready', async () => {
+    console.log('Redis ready - re-subscribing to all channels');
+    await safeSubscribe('host_metrics',   (msg) => forward('host_metrics',   msg));
+    await safeSubscribe('client_summary', (msg) => forward('client_summary', msg));
+  });
+
+  /* Optional: if the connection ends for any reason, close the process */
+  sub.on('end', () => {
+    console.error('Redis connection closed - exiting');
+    process.exit(1);
+  });
+})();
+
+/* --------------------------------------------------------------------- */
+/* ---------- 5. Start the HTTP server --------------------------------- */
+/* --------------------------------------------------------------------- */
+const PORT = process.env.PORT || 3000;
+server.listen(PORT, () => {
+  console.log(`Server listening on http://localhost:${PORT}`);
+});