Initial commit - Resource Monitor with Ubuntu installer

server/monitorService.js

@@ -0,0 +1,116 @@
+const axios = require('axios');
+const db = require('./database');
+
+class MonitorService {
+  async checkResource(resource) {
+    const startTime = Date.now();
+    let result = {
+      resource_id: resource.id,
+      status: 'down',
+      response_time: null,
+      status_code: null,
+      error_message: null,
+    };
+
+    try {
+      const response = await axios.get(resource.url, {
+        timeout: resource.timeout,
+        validateStatus: () => true, // Don't throw on any status
+      });
+
+      const responseTime = Date.now() - startTime;
+      const isUp = response.status >= 200 && response.status < 400;
+
+      result = {
+        ...result,
+        status: isUp ? 'up' : 'down',
+        response_time: responseTime,
+        status_code: response.status,
+        error_message: isUp ? null : `HTTP ${response.status}`,
+      };
+    } catch (error) {
+      result.error_message = error.message;
+      result.response_time = Date.now() - startTime;
+    }
+
+    return result;
+  }
+
+  saveCheck(check) {
+    const stmt = db.prepare(`
+      INSERT INTO checks (resource_id, status, response_time, status_code, error_message)
+      VALUES (?, ?, ?, ?, ?)
+    `);
+    stmt.run(
+      check.resource_id,
+      check.status,
+      check.response_time,
+      check.status_code,
+      check.error_message
+    );
+  }
+
+  getLastCheck(resourceId) {
+    return db.prepare(`
+      SELECT * FROM checks 
+      WHERE resource_id = ? 
+      ORDER BY checked_at DESC 
+      LIMIT 1
+    `).get(resourceId);
+  }
+
+  handleIncident(resourceId, isDown) {
+    const activeIncident = db.prepare(`
+      SELECT * FROM incidents 
+      WHERE resource_id = ? AND resolved_at IS NULL
+    `).get(resourceId);
+
+    if (isDown && !activeIncident) {
+      // Start new incident
+      db.prepare(`
+        INSERT INTO incidents (resource_id) VALUES (?)
+      `).run(resourceId);
+      return { type: 'started', incident: true };
+    } else if (!isDown && activeIncident) {
+      // Resolve incident
+      db.prepare(`
+        UPDATE incidents 
+        SET resolved_at = CURRENT_TIMESTAMP 
+        WHERE id = ?
+      `).run(activeIncident.id);
+      return { type: 'resolved', incident: activeIncident };
+    }
+
+    return { type: 'none' };
+  }
+
+  getResourceStats(resourceId, hours = 24) {
+    const checks = db.prepare(`
+      SELECT * FROM checks 
+      WHERE resource_id = ? 
+      AND checked_at >= datetime('now', '-' || ? || ' hours')
+      ORDER BY checked_at ASC
+    `).all(resourceId, hours);
+
+    const upChecks = checks.filter(c => c.status === 'up');
+    const totalChecks = checks.length;
+    const uptime = totalChecks > 0 ? (upChecks.length / totalChecks) * 100 : 0;
+
+    const responseTimes = checks
+      .filter(c => c.response_time !== null)
+      .map(c => c.response_time);
+
+    const avgResponseTime = responseTimes.length > 0
+      ? responseTimes.reduce((a, b) => a + b, 0) / responseTimes.length
+      : 0;
+
+    return {
+      uptime: uptime.toFixed(2),
+      avgResponseTime: avgResponseTime.toFixed(0),
+      totalChecks,
+      checks: checks.slice(-50), // Last 50 checks
+    };
+  }
+}
+
+module.exports = new MonitorService();