Unify URL resolution, add health checker sync, and make modules optional

- Add url-resolver.js with single resolveServiceUrl() used by all 5 consumers
  (probes, health routes, health checker auto-config)
- Health checker now does full sync (add/update/remove) instead of add-only,
  and re-syncs automatically after every services.json mutation
- docker-maintenance and log-digest are now optional imports with try/catch,
  preventing container crashes when these files are absent
- Add null guards in routes/logs.js for graceful 503 responses

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

dashcaddy-api/routes/context.js

@@ -111,10 +111,12 @@ const ctx = {
   logError: null,
   safeErrorMessage: null,
   buildDomain: null,
+  buildServiceUrl: null,
   getServiceById: null,
   readConfig: null,
   saveConfig: null,
   addServiceToConfig: null,
+  resyncHealthChecker: null,
   validateURL: null,
 
   // Middleware

dashcaddy-api/routes/health.js

@@ -6,6 +6,7 @@ const { TIMEOUTS } = require('../constants');
 const { exists } = require('../fs-helpers');
 const { paginate, parsePaginationParams } = require('../pagination');
 const platformPaths = require('../platform-paths');
+const { resolveServiceUrl } = require('../url-resolver');
 
 module.exports = function(ctx) {
   const router = express.Router();
@@ -36,18 +37,7 @@ module.exports = function(ctx) {
         let checkType = 'http';
 
         // Determine URL to check
-        if (service.isExternal && service.externalUrl) {
+        url = resolveServiceUrl(serviceId, service, ctx.siteConfig, ctx.buildServiceUrl);
-          url = service.externalUrl;
-        } else if (service.containerId || service.containerName) {
-          // Local container - check via localhost and port
-          const port = service.port || 80;
-          url = `http://localhost:${port}`;
-        } else if (service.url) {
-          url = service.url.startsWith('http') ? service.url : `https://${service.url}`;
-        } else if (service.id) {
-          // Try common URL pattern
-          url = `https://${ctx.buildDomain(service.id)}`;
-        }
 
         if (!url) {
           health[serviceId] = { status: 'unknown', reason: 'No URL configured' };
@@ -157,14 +147,7 @@ module.exports = function(ctx) {
     }
 
     // Determine URL
-    let url = null;
+    const url = resolveServiceUrl(serviceId, service, ctx.siteConfig, ctx.buildServiceUrl);
-    if (service.isExternal && service.externalUrl) {
-      url = service.externalUrl;
-    } else if (service.url) {
-      url = service.url.startsWith('http') ? service.url : `https://${service.url}`;
-    } else {
-      url = `https://${ctx.buildDomain(serviceId)}`;
-    }
 
     // Check health
     const controller = new AbortController();

dashcaddy-api/routes/logs.js

@@ -140,6 +140,7 @@ module.exports = function(ctx) {
 
   // Get latest daily digest
   router.get('/logs/digest/latest', ctx.asyncHandler(async (req, res) => {
+    if (!ctx.logDigest) return ctx.errorResponse(res, 503, 'Log digest not available');
     const digest = await ctx.logDigest.getLatestDigest();
     if (!digest) {
       return res.json({ success: true, digest: null, message: 'No digest available yet. First digest is generated at midnight.' });
@@ -149,18 +150,21 @@ module.exports = function(ctx) {
 
   // Get live digest data (today's accumulated stats)
   router.get('/logs/digest/live', ctx.asyncHandler(async (req, res) => {
+    if (!ctx.logDigest) return ctx.errorResponse(res, 503, 'Log digest not available');
     const live = ctx.logDigest.getLiveData();
     res.json({ success: true, ...live });
   }, 'logs-digest-live'));
 
   // List available digest dates
   router.get('/logs/digest/history', ctx.asyncHandler(async (req, res) => {
+    if (!ctx.logDigest) return ctx.errorResponse(res, 503, 'Log digest not available');
     const dates = await ctx.logDigest.listDigests();
     res.json({ success: true, dates });
   }, 'logs-digest-history'));
 
   // Generate digest on demand (for today or a specific date)
   router.post('/logs/digest/generate', ctx.asyncHandler(async (req, res) => {
+    if (!ctx.logDigest) return ctx.errorResponse(res, 503, 'Log digest not available');
     const date = req.body.date || new Date().toISOString().slice(0, 10);
     const digest = await ctx.logDigest.generateDailyDigest(date);
     res.json({ success: true, digest });
@@ -168,6 +172,7 @@ module.exports = function(ctx) {
 
   // Get digest for a specific date (JSON)
   router.get('/logs/digest/:date', ctx.asyncHandler(async (req, res) => {
+    if (!ctx.logDigest) return ctx.errorResponse(res, 503, 'Log digest not available');
     const { date } = req.params;
     if (!/^\d{4}-\d{2}-\d{2}$/.test(date)) {
       return ctx.errorResponse(res, 400, 'Invalid date format. Use YYYY-MM-DD.');
@@ -186,6 +191,7 @@ module.exports = function(ctx) {
 
   // Get Docker disk usage snapshot
   router.get('/logs/docker-disk', ctx.asyncHandler(async (req, res) => {
+    if (!ctx.dockerMaintenance) return ctx.errorResponse(res, 503, 'Docker maintenance not available');
     const diskUsage = await ctx.dockerMaintenance.getDiskUsage();
     const status = ctx.dockerMaintenance.getStatus();
     res.json({ success: true, diskUsage, maintenance: status });
@@ -193,6 +199,7 @@ module.exports = function(ctx) {
 
   // Trigger Docker maintenance manually
   router.post('/logs/docker-maintenance', ctx.asyncHandler(async (req, res) => {
+    if (!ctx.dockerMaintenance) return ctx.errorResponse(res, 503, 'Docker maintenance not available');
     const result = await ctx.dockerMaintenance.runMaintenance();
     res.json({ success: true, result });
   }, 'logs-docker-maintenance'));

dashcaddy-api/routes/services.js

@@ -8,6 +8,7 @@ const { APP, REGEX, TIMEOUTS } = require('../constants');
 const { validateServiceConfig, isValidPort } = require('../input-validator');
 const { exists } = require('../fs-helpers');
 const { paginate, parsePaginationParams } = require('../pagination');
+const { resolveServiceUrl } = require('../url-resolver');
 
 module.exports = function(ctx) {
   const router = express.Router();
@@ -33,10 +34,7 @@ module.exports = function(ctx) {
   }
 
   function resolveProbeUrl(id, service) {
-    if (id === 'internet') return 'https://www.google.com';
+    return resolveServiceUrl(id, service, ctx.siteConfig, ctx.buildServiceUrl);
-    if (service?.isExternal && service.externalUrl) return service.externalUrl;
-    if (service?.url) return service.url.startsWith('http') ? service.url : `https://${service.url}`;
-    return ctx.buildServiceUrl(id);
   }
 
   function requestStatusCode(url, method) {
@@ -308,6 +306,7 @@ module.exports = function(ctx) {
         return services;
       });
 
+      ctx.resyncHealthChecker?.().catch(() => {});
       res.json({ success: true, message: `Service "${name}" added to dashboard` });
     } catch (error) {
       ctx.log.error('deploy', 'Error adding service', { error: error.message });
@@ -339,6 +338,7 @@ module.exports = function(ctx) {
     }
 
     await ctx.servicesStateManager.write(services);
+    ctx.resyncHealthChecker?.().catch(() => {});
 
     res.json({
       success: true,
@@ -367,6 +367,7 @@ module.exports = function(ctx) {
       return ctx.errorResponse(res, 404, `Service "${id}" not found`);
     }
 
+    ctx.resyncHealthChecker?.().catch(() => {});
     res.json({ success: true, message: `Service "${id}" removed from dashboard` });
   }, 'services-delete'));
 
@@ -454,6 +455,7 @@ module.exports = function(ctx) {
       });
     }
 
+    ctx.resyncHealthChecker?.().catch(() => {});
     res.json({
       success: true,
       message: `Service updated: ${oldSubdomain} -> ${newSubdomain}`,

dashcaddy-api/server.js

@@ -17,6 +17,7 @@ const credentialManager = require('./credential-manager');
 const { CACHE_CONFIGS, createCache } = require('./cache-config');
 const { AppError } = require('./errors');
 const { validateConfig } = require('./config-schema');
+const { resolveServiceUrl } = require('./url-resolver');
 const {
   APP, APP_PORTS, ARR_SERVICES, TIMEOUTS, RETRIES,
   SESSION_TTL, RATE_LIMITS, CADDY, PLEX, LIMITS,
@@ -50,8 +51,10 @@ const backupManager = require('./backup-manager');
 const healthChecker = require('./health-checker');
 const updateManager = require('./update-manager');
 const selfUpdater = require('./self-updater');
-const dockerMaintenance = require('./docker-maintenance');
+let dockerMaintenance;
-const logDigest = require('./log-digest');
+try { dockerMaintenance = require('./docker-maintenance'); } catch (_) { console.warn('[WARN] docker-maintenance module not found, skipped'); }
+let logDigest;
+try { logDigest = require('./log-digest'); } catch (_) { console.warn('[WARN] log-digest module not found, skipped'); }
 const StateManager = require('./state-manager');
 const auditLogger = require('./audit-logger');
 const portLockManager = require('./port-lock-manager');
@@ -1173,6 +1176,7 @@ Object.assign(ctx, {
   loadDnsCredentials: () => {},
   SERVICES_FILE, CONFIG_FILE, TOTP_CONFIG_FILE, TAILSCALE_CONFIG_FILE,
   NOTIFICATIONS_FILE, ERROR_LOG_FILE,
+  resyncHealthChecker: () => syncHealthCheckerServices({ log, SERVICES_FILE, servicesStateManager, healthChecker, buildServiceUrl, siteConfig, APP }),
 });
 
 // Build versioned API router — all route modules attach here
@@ -1225,29 +1229,15 @@ app.get('/probe/:id', asyncHandler(async (req, res) => {
   const id = req.params.id;
 
   try {
-    let url;
+    // Look up service in services.json
-
-    if (id === 'internet') {
-      // Internet connectivity check
-      url = 'https://www.google.com';
-    } else {
-      // Look up service in services.json for custom URLs
     let service = null;
-      if (await exists(SERVICES_FILE)) {
+    if (id !== 'internet' && await exists(SERVICES_FILE)) {
       const data = await servicesStateManager.read();
       const services = Array.isArray(data) ? data : data.services || [];
       service = services.find(s => s.id === id);
     }
 
-      if (service?.isExternal && service?.externalUrl) {
+    const url = resolveServiceUrl(id, service, siteConfig, buildServiceUrl);
-        url = service.externalUrl;
-      } else if (service?.url) {
-        url = service.url.startsWith('http') ? service.url : `https://${service.url}`;
-      } else {
-        // Build URL from configured routing mode (subdomain or subdirectory)
-        url = buildServiceUrl(id);
-      }
-    }
 
     const parsed = new URL(url);
     const isHttps = parsed.protocol === 'https:';
@@ -1734,6 +1724,8 @@ async function addServiceToConfig(service) {
       return services;
     });
     log.info('deploy', 'Service added to config', { serviceId: service.id });
+    // Sync health checker with updated services list
+    ctx.resyncHealthChecker?.().catch(() => {});
   } catch (error) {
     log.error('deploy', 'Failed to add service to config', { serviceId: service.id, error: error.message });
     throw error;
@@ -1852,7 +1844,7 @@ const server = app.listen(PORT, '0.0.0.0', () => {
   (async () => {
     try {
       // Auto-configure health checker from services.json
-      await syncHealthCheckerServices({ log, SERVICES_FILE, servicesStateManager, healthChecker, buildDomain, APP });
+      await syncHealthCheckerServices({ log, SERVICES_FILE, servicesStateManager, healthChecker, buildServiceUrl, siteConfig, APP });
       healthChecker.start();
       log.info('server', 'Health checker started');
     } catch (error) {
@@ -1887,6 +1879,7 @@ const server = app.listen(PORT, '0.0.0.0', () => {
     log.error('server', 'Self-updater failed to start', { error: error.message });
   }
   
+  if (dockerMaintenance) {
     try {
       dockerMaintenance.start();
       log.info('server', 'Docker maintenance started');
@@ -1906,7 +1899,9 @@ const server = app.listen(PORT, '0.0.0.0', () => {
     } catch (error) {
       log.error('server', 'Docker maintenance failed to start', { error: error.message });
     }
+  }
 
+  if (logDigest) {
     try {
       logDigest.start(platformPaths.digestDir);
       log.info('server', 'Log digest started', { digestDir: platformPaths.digestDir });
@@ -1919,6 +1914,7 @@ const server = app.listen(PORT, '0.0.0.0', () => {
     } catch (error) {
       log.error('server', 'Log digest failed to start', { error: error.message });
     }
+  }
 
   // Tailscale API sync (if OAuth configured)
   if (tailscaleConfig.oauthConfigured) {
@@ -1935,8 +1931,8 @@ function shutdown(signal) {
   log.info('shutdown', `${signal} received, draining connections...`);
   resourceMonitor.stop();
   backupManager.stop();
-  dockerMaintenance.stop();
+  if (dockerMaintenance) dockerMaintenance.stop();
-  logDigest.stop();
+  if (logDigest) logDigest.stop();
   healthChecker.stop();
   updateManager.stop();
   selfUpdater.stop();

dashcaddy-api/startup-validator.js

@@ -10,6 +10,7 @@ const path = require('path');
 const http = require('http');
 const https = require('https');
 const { exists, isAccessible } = require('./fs-helpers');
+const { resolveServiceUrl } = require('./url-resolver');
 
 /**
  * Validate startup configuration and environment.
@@ -146,17 +147,19 @@ async function validateStartupConfig({ log, CADDYFILE_PATH, SERVICES_FILE, CONFI
 }
 
 /**
- * Auto-configure health checker from services.json + top-card services.
+ * Full-sync health checker from services.json + top-card services.
+ * Adds missing, updates changed URLs, removes deleted services.
  *
  * @param {Object} deps
  * @param {Function} deps.log - structured logger
  * @param {string} deps.SERVICES_FILE
  * @param {Object} deps.servicesStateManager - StateManager instance
  * @param {Object} deps.healthChecker - health checker module
- * @param {Function} deps.buildDomain - builds domain from subdomain
+ * @param {Function} deps.buildServiceUrl - canonical URL builder
+ * @param {Object} deps.siteConfig - site config (dnsServers, etc.)
  * @param {Object} deps.APP - app constants (USER_AGENTS)
  */
-async function syncHealthCheckerServices({ log, SERVICES_FILE, servicesStateManager, healthChecker, buildDomain, APP }) {
+async function syncHealthCheckerServices({ log, SERVICES_FILE, servicesStateManager, healthChecker, buildServiceUrl, siteConfig, APP }) {
   try {
     const topCardServices = [
       { id: 'dns1', name: 'DNS1' },
@@ -164,6 +167,11 @@ async function syncHealthCheckerServices({ log, SERVICES_FILE, servicesStateMana
       { id: 'internet', name: 'Internet' },
     ];
 
+    // Add dns3 if it exists in dnsServers config
+    if (siteConfig?.dnsServers?.dns3) {
+      topCardServices.push({ id: 'dns3', name: 'DNS3' });
+    }
+
     let appServices = [];
     if (await exists(SERVICES_FILE)) {
       const data = await servicesStateManager.read();
@@ -171,22 +179,18 @@ async function syncHealthCheckerServices({ log, SERVICES_FILE, servicesStateMana
     }
 
     const allServices = [...topCardServices, ...appServices];
-    const configuredIds = new Set(Object.keys(healthChecker.config.services || {}));
+    const desiredIds = new Set();
-    let added = 0;
+    let added = 0, updated = 0, removed = 0;
 
     for (const svc of allServices) {
       const id = svc.id || svc.name?.toLowerCase();
-      if (!id || configuredIds.has(id)) continue;
+      if (!id) continue;
+      desiredIds.add(id);
 
-      let url;
+      const url = resolveServiceUrl(id, svc, siteConfig, buildServiceUrl);
-      if (id === 'internet') {
+      const existing = healthChecker.config.services?.[id];
-        url = 'https://www.google.com';
-      } else if (svc.isExternal && svc.externalUrl) {
-        url = svc.externalUrl;
-      } else {
-        url = `https://${buildDomain(id)}`;
-      }
 
+      if (!existing) {
         healthChecker.configureService(id, {
           name: svc.name || id,
           url,
@@ -196,13 +200,26 @@ async function syncHealthCheckerServices({ log, SERVICES_FILE, servicesStateMana
           headers: { 'User-Agent': APP.USER_AGENTS.HEALTH },
         });
         added++;
+      } else if (existing.url !== url) {
+        healthChecker.configureService(id, { ...existing, url });
+        updated++;
+      }
     }
 
-    if (added > 0) {
+    // Remove services no longer in the desired set
-      log.info('health', 'Auto-configured services from services.json', { count: added });
+    const configuredIds = Object.keys(healthChecker.config.services || {});
+    for (const id of configuredIds) {
+      if (!desiredIds.has(id)) {
+        healthChecker.removeService(id);
+        removed++;
+      }
+    }
+
+    if (added > 0 || updated > 0 || removed > 0) {
+      log.info('health', 'Health checker synced', { added, updated, removed });
     }
   } catch (error) {
-    log.error('health', 'Error syncing services', { error: error.message });
+    log.error('health', 'Error syncing health checker', { error: error.message });
   }
 }
 

dashcaddy-api/url-resolver.js

@@ -0,0 +1,32 @@
+/**
+ * Unified URL Resolver
+ * Single source of truth for resolving service URLs across all systems
+ * (probes, health checks, health checker auto-config, SSO).
+ */
+
+/**
+ * Resolve the canonical URL for a service.
+ *
+ * Priority:
+ *   1. internet → https://www.google.com
+ *   2. isExternal + externalUrl → use as-is
+ *   3. service.url → prepend https:// if no protocol
+ *   4. dnsServers config → http://{ip}:{port}
+ *   5. fallback → buildServiceUrl(id)
+ *
+ * @param {string} id - service identifier
+ * @param {Object|null} service - service object from services.json (may be null for top-card services)
+ * @param {Object|null} siteConfig - site config containing dnsServers etc.
+ * @param {Function} buildServiceUrl - fallback URL builder (subdomain or subdirectory mode)
+ * @returns {string} resolved URL
+ */
+function resolveServiceUrl(id, service, siteConfig, buildServiceUrl) {
+  if (id === 'internet') return 'https://www.google.com';
+  if (service?.isExternal && service.externalUrl) return service.externalUrl;
+  if (service?.url) return service.url.startsWith('http') ? service.url : `https://${service.url}`;
+  const dnsServer = siteConfig?.dnsServers?.[id];
+  if (dnsServer) return `http://${dnsServer.ip}:${dnsServer.port || 5380}`;
+  return buildServiceUrl(id);
+}
+
+module.exports = { resolveServiceUrl };