feat: implement WebSocket server for real-time sensor data handling and add sensor status update routes

realtime/src/routes/sessions.js

@@ -1,14 +1,59 @@
 const router = require('express').Router();
 const db = require('../store/db');
-const { query } = require('../store/redis');
+const { queryAll, query } = require('../store/redis');
 
-router.get('/pendingtokens', (req, res) => {
+router.get('/', async (req, res) => {
+    try {
+        const keys = await queryAll('sensors');
+        const sessions = {};
+        for (const key of keys) {
+            const name = key.replace('sensors:', '');
+            const info = await query(name, 'sensors');
+            sessions[name] = {
+                name,
+                connectedAt: info.timestamp || null,
+                session: info.session || null,
+                status: info.status || 'unknown',
+            };
+        }
+        res.json(sessions);
+    } catch (err) {
+        console.error('Error fetching sessions', err);
+        res.status(500).json({ error: 'internal server error' });
+    }
+});
+
+router.get('/pending', (req, res) => {
     try {
         const pendingTokens = queryAll('snsr_pending_token');
         res.json(pendingTokens);
     } catch (err) {
         console.error('Error fetching pending tokens', err);
-        res.status(500).json({ error: 'internal server error' });
+        res.status(500).json({ error: `Error fetching pending tokens, ${err}` });
+    }
+});
+
+router.get('/connected', (req, res) => {
+    try {
+        const connectedSensors = queryAll('snsr_connected');
+        res.json(connectedSensors);
+    } catch (err) {
+        console.error('Error fetching connected sensors', err);
+        res.status(500).json({ error: `Error fetching connected sensors, ${err}` });
+    }
+});
+
+router.get('/connected/:id', async (req, res) => {
+    const { id } = req.params;
+    try {
+        const sensor = await query(`snsr_connected:${id}`);
+        if (!sensor) {
+            return res.status(404).json({ error: 'sensor not connected' });
+        }
+        res.json({ id, name: sensor });
+    } catch (err) {
+        console.error('Error fetching sensor connection status', err);
+        res.status(500).json({ error: `Error fetching sensor connection status, ${err}` });
     }
 });