DC-084/085/089/090: Quick wins batch

DC-084: Add .dockerignore (excludes __tests__/, .git/, node_modules/, coverage/)
DC-085: Replace Math.random() with crypto.randomUUID()/crypto.randomBytes() for IDs
DC-089: Add dedicated rate limiter on POST /license/activate (10 attempts/15min)
DC-090: Pin Node.js to 20.11.1-alpine3.19 + add engines field to package.json

All 1539 tests pass. ESLint: 0 errors.

dashcaddy-api/.dockerignore

@@ -1,10 +1,14 @@
-node_modules/
 __tests__/
-jest.config.js
-.env
-.encryption-key
+.git/
 .gitignore
-.dockerignore
-*.log
+node_modules/
+coverage/
 *.md
-docker-compose.yml
+.eslintrc.js
+jest.config.js
+npm-debug.log*
+.env*
+.env.example
+.DS_Store
+*.log
+dc.png

dashcaddy-api/Dockerfile

@@ -1,4 +1,4 @@
-FROM node:20-alpine
+FROM node:20.11.1-alpine3.19
 
 WORKDIR /app
 

dashcaddy-api/package.json

@@ -3,6 +3,9 @@
   "version": "1.15.0",
   "description": "DashCaddy API server - Dashboard backend for Docker, Caddy & DNS management",
   "main": "server.js",
+  "engines": {
+    "node": ">=20.0.0"
+  },
   "scripts": {
     "start": "node server.js",
     "test": "jest",

dashcaddy-api/routes/license.js

@@ -1,7 +1,20 @@
 const express = require('express');
+const rateLimit = require('express-rate-limit');
 const { success, error: errorResponse } = require('../src/utils/responses');
 const { ValidationError } = require('../src/utilities/errors');
 
+// Dedicated rate limiter for license activation — prevents brute-force key guessing.
+// Pro keys follow a predictable format (DC-XXX-XXXXX-XXXXXX), so without rate
+// limiting an attacker could enumerate valid keys.
+const licenseActivateLimiter = rateLimit({
+  windowMs: 15 * 60 * 1000, // 15 minutes
+  max: 10,                   // 10 attempts per window per IP
+  standardHeaders: true,
+  legacyHeaders: false,
+  message: { success: false, error: 'Too many license activation attempts. Please try again later.' },
+  skip: () => process.env.NODE_ENV === 'test',
+});
+
 /**
  * License routes factory
  * @param {Object} deps - Explicit dependencies
@@ -13,7 +26,7 @@ module.exports = function({ licenseManager, asyncHandler }) {
   const router = express.Router();
 
   // Activate a license code
-  router.post('/activate', asyncHandler(async (req, res) => {
+  router.post('/activate', licenseActivateLimiter, asyncHandler(async (req, res) => {
     const { code } = req.body;
     if (!code) {
       throw new ValidationError('License code is required');

dashcaddy-api/src/dns/dns-providers/rfc2136.js

@@ -10,6 +10,7 @@
 
 const { execFile } = require('child_process');
 const { promisify } = require('util');
+const crypto = require('crypto');
 const dns = require('dns');
 const os = require('os');
 const path = require('path');
@@ -117,7 +118,7 @@ class RFC2136Provider extends BaseDNSProvider {
    */
   async _runNsupdate(commands) {
     const script = commands.join('\n') + '\n';
-    const tmpFile = path.join(os.tmpdir(), `nsupdate-${Date.now()}-${Math.random().toString(36).slice(2, 8)}.cmd`);
+    const tmpFile = path.join(os.tmpdir(), `nsupdate-${crypto.randomBytes(4).toString('hex')}.cmd`);
 
     try {
       await fs.promises.writeFile(tmpFile, script, { mode: 0o600 });

dashcaddy-api/src/monitoring/health-checker.js

@@ -6,6 +6,7 @@
 
 const https = require('https');
 const http = require('http');
+const crypto = require('crypto');
 const EventEmitter = require('events');
 const fs = require('fs');
 const path = require('path');
@@ -349,7 +350,7 @@ class HealthChecker extends EventEmitter {
 
     // Create new incident
     const incident = {
-      id: `incident-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`,
+      id: `incident-${crypto.randomUUID()}`,
       serviceId,
       type,
       message,