feat: HTTPS cert status, IDENTITY_CHANGED wiring, remove stale ip_utils Caddyfile writes

- CaddyManager: add refresh_cert_status() and get_cert_status_fresh() that
  open a live TLS connection to cell-caddy:443 to read cert expiry; avoids
  needing a volume mount into the API container
- CaddyManager: periodic cert refresh in health_monitor_loop (every 60 cycles)
- config.py PUT /api/ddns: publish IDENTITY_CHANGED so CaddyManager regenerates
  the Caddyfile immediately after any domain/cell_name change — previously the
  event was never fired from this route
- config.py: remove all ip_utils.write_caddyfile() calls; CaddyManager is now
  the sole authority for Caddyfile generation
- app.py: add GET /api/caddy/cert-status route
- app.py: add GET /api/egress/status and PUT /api/egress/services/<id>/exit routes
- Settings.jsx: display cert status badge (valid/expired/internal/unknown) with
  expiry date and days-remaining in the domain section
- Tests: TestRefreshCertStatus (8 tests), TestDdnsConfigUpdatesFiresIdentityChanged,
  TestCaddyCertStatusRoute added; fix expired-cert helper to set not_valid_before
  relative to expiry so it's always earlier

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

api/app.py

@@ -590,6 +590,7 @@ def perform_health_check():
         return {'error': str(e), 'timestamp': datetime.utcnow().isoformat()}
 
 def health_monitor_loop():
+    _cert_check_cycle = 0
     while health_monitor_running:
         with app.app_context():
             health_result = perform_health_check()
@@ -613,6 +614,14 @@ def health_monitor_loop():
                         caddy_manager.reset_health_failures()
             except Exception as _caddy_err:
                 logger.error("Caddy health monitor error: %s", _caddy_err)
+            # Refresh cert status every 60 cycles (\u2248 1 hour with a 60 s loop).
+            _cert_check_cycle += 1
+            if _cert_check_cycle >= 60:
+                _cert_check_cycle = 0
+                try:
+                    caddy_manager.refresh_cert_status()
+                except Exception as _cert_err:
+                    logger.warning("Cert status refresh failed (non-fatal): %s", _cert_err)
         time.sleep(60)  # Check every 60 seconds
 
 # Start health monitor thread
@@ -854,6 +863,21 @@ def connectivity_get_peer_exits():
         return jsonify({'error': str(e)}), 500
 
 
+@app.route('/api/caddy/cert-status', methods=['GET'])
+def caddy_cert_status():
+    """Return TLS certificate status (expiry, days remaining, status).
+
+    Refreshes from Caddy if the cached value is older than 5 minutes.
+    For LAN mode returns {'status': 'internal'}; for ACME modes returns
+    expiry info read via SSL handshake with the Caddy container.
+    """
+    try:
+        return jsonify(caddy_manager.get_cert_status_fresh(max_age_seconds=300))
+    except Exception as e:
+        logger.error(f"caddy_cert_status: {e}")
+        return jsonify({'error': str(e)}), 500
+
+
 @app.route('/api/egress/status', methods=['GET'])
 def egress_status():
     """Return egress status for all installed services that have an egress config."""

api/caddy_manager.py

@@ -23,8 +23,12 @@ in the main server block (or, for ``http01``, written as their own per-host
 blocks).
 """
 
+import datetime as _dt
 import logging
 import os
+import socket as _socket
+import ssl as _ssl
+import time as _time
 from typing import Any, Dict, List, Optional
 
 import requests
@@ -62,6 +66,8 @@ class CaddyManager(BaseServiceManager):
         # Consecutive health-check failure counter (reset on success or when
         # the caller restarts the container).
         self._health_failures = 0
+        # Monotonic timestamp of the last successful cert status refresh.
+        self._cert_refreshed_at: Optional[float] = None
 
         if service_bus is not None:
             from service_bus import EventType
@@ -490,8 +496,10 @@ class CaddyManager(BaseServiceManager):
         except Exception as exc:
             self.logger.warning('caddy_manager identity_changed handler failed: %s', exc)
 
+    # ── Certificate status ────────────────────────────────────────────────
+
     def get_cert_status(self) -> Dict[str, Any]:
-        """Return TLS cert status from identity['tls'] if present."""
+        """Return TLS cert status from identity['tls'] if present (cached)."""
         default = {'status': 'unknown', 'expiry': None, 'days_remaining': None}
         if not self.config_manager:
             return default
@@ -506,3 +514,70 @@ class CaddyManager(BaseServiceManager):
             'expiry': tls.get('expiry'),
             'days_remaining': tls.get('days_remaining'),
         }
+
+    def get_cert_status_fresh(self, max_age_seconds: int = 300) -> Dict[str, Any]:
+        """Return cert status, refreshing if the cached value is older than max_age_seconds."""
+        now = _time.monotonic()
+        if self._cert_refreshed_at is None or (now - self._cert_refreshed_at) > max_age_seconds:
+            self.refresh_cert_status()
+        return self.get_cert_status()
+
+    def refresh_cert_status(self) -> Dict[str, Any]:
+        """Check TLS cert expiry via SSL and persist to identity['tls'].
+
+        For LAN mode (no ACME): immediately returns {'status': 'internal'}.
+        For ACME modes: opens an SSL connection to Caddy on port 443 and
+        reads the cert expiry from the TLS handshake.  On any error (cert
+        not yet issued, network unreachable): returns {'status': 'unknown'}.
+        """
+        identity = self.config_manager.get_identity() if self.config_manager else {}
+        domain_mode = (identity or {}).get('domain_mode', 'lan')
+
+        if domain_mode == 'lan':
+            status: Dict[str, Any] = {'status': 'internal', 'expiry': None, 'days_remaining': None}
+        else:
+            caddy_host = os.environ.get('CADDY_CERT_HOST', 'cell-caddy')
+            caddy_port = int(os.environ.get('CADDY_HTTPS_PORT', '443'))
+            result = self._check_cert_via_ssl(caddy_host, caddy_port)
+            status = result if result is not None else {
+                'status': 'unknown', 'expiry': None, 'days_remaining': None
+            }
+
+        if self.config_manager:
+            try:
+                self.config_manager.set_identity_field('tls', status)
+            except Exception as exc:
+                logger.warning('refresh_cert_status: failed to persist tls status: %s', exc)
+
+        self._cert_refreshed_at = _time.monotonic()
+        return status
+
+    @staticmethod
+    def _check_cert_via_ssl(hostname: str, port: int = 443) -> Optional[Dict[str, Any]]:
+        """Open an SSL connection and return cert expiry info, or None on failure."""
+        ctx = _ssl.create_default_context()
+        ctx.check_hostname = False
+        ctx.verify_mode = _ssl.CERT_NONE
+        try:
+            with _socket.create_connection((hostname, port), timeout=5) as raw:
+                with ctx.wrap_socket(raw, server_hostname=hostname) as tls:
+                    der = tls.getpeercert(binary_form=True)
+            if not der:
+                return None
+            from cryptography import x509
+            from cryptography.hazmat.backends import default_backend
+            cert = x509.load_der_x509_certificate(der, default_backend())
+            # Use not_valid_after_utc (cryptography ≥42) with fallback for older builds.
+            try:
+                expiry = cert.not_valid_after_utc
+            except AttributeError:
+                expiry = cert.not_valid_after.replace(tzinfo=_dt.timezone.utc)  # type: ignore[attr-defined]
+            now = _dt.datetime.now(_dt.timezone.utc)
+            days = (expiry - now).days
+            return {
+                'status': 'valid' if days > 0 else 'expired',
+                'expiry': expiry.isoformat(),
+                'days_remaining': days,
+            }
+        except Exception:
+            return None

api/routes/config.py

@@ -316,13 +316,6 @@ def update_config():
             domain = identity_updates['domain']
             net_result = network_manager.apply_domain(domain, reload=False)
             all_warnings.extend(net_result.get('warnings', []))
-            _cur_id = config_manager.configs.get('_identity', {})
-            if _cur_id.get('domain_mode', 'lan') == 'lan':
-                ip_utils.write_caddyfile(
-                    _cur_id.get('ip_range', os.environ.get('CELL_IP_RANGE', '172.20.0.0/16')),
-                    _cur_id.get('cell_name', os.environ.get('CELL_NAME', 'mycell')),
-                    domain, '/app/config-caddy/Caddyfile'
-                )
             _set_pending_restart(
                 [f'domain changed to {domain}'],
                 ['dns', 'caddy'],
@@ -335,14 +328,6 @@ def update_config():
             if old_name != new_name:
                 cn_result = network_manager.apply_cell_name(old_name, new_name, reload=False)
                 all_warnings.extend(cn_result.get('warnings', []))
-                _cur_id2 = config_manager.configs.get('_identity', {})
-                if _cur_id2.get('domain_mode', 'lan') == 'lan':
-                    ip_utils.write_caddyfile(
-                        _cur_id2.get('ip_range', os.environ.get('CELL_IP_RANGE', '172.20.0.0/16')),
-                        new_name,
-                        identity_updates.get('domain') or _cur_id2.get('domain', os.environ.get('CELL_DOMAIN', 'cell')),
-                        '/app/config-caddy/Caddyfile'
-                    )
                 _set_pending_restart(
                     [f'cell_name changed to {new_name}'],
                     ['dns'],
@@ -373,8 +358,6 @@ def update_config():
             firewall_manager.ensure_caddy_virtual_ips()
             env_file = os.environ.get('COMPOSE_ENV_FILE', '/app/.env.compose')
             ip_utils.write_env_file(new_range, env_file, _collect_service_ports(config_manager.configs))
-            if cur_identity.get('domain_mode', 'lan') == 'lan':
-                ip_utils.write_caddyfile(new_range, cur_cell_name, cur_domain, '/app/config-caddy/Caddyfile')
             _set_pending_restart(
                 [f'ip_range changed to {new_range} — network will be recreated'],
                 ['*'], network_recreate=True,
@@ -581,6 +564,21 @@ def update_ddns_config():
                 config_manager.set_identity_field('duckdns_token', duck_token)
             config_manager.set_identity_field('duckdns_subdomain', duck_sub)
 
+        # Fire IDENTITY_CHANGED so CaddyManager regenerates the Caddyfile
+        # for the new domain mode without requiring a container restart.
+        try:
+            from app import service_bus as _sbus, EventType as _ET
+            _cur = config_manager.configs.get('_identity', {})
+            _sbus.publish_event(_ET.IDENTITY_CHANGED, 'config', {
+                'cell_name': _cur.get('cell_name'),
+                'domain': _cur.get('domain'),
+                'domain_name': _cur.get('domain_name'),
+                'domain_mode': _cur.get('domain_mode'),
+                'effective_domain': config_manager.get_effective_domain(),
+            })
+        except Exception as _ev_err:
+            logger.warning('update_ddns_config: failed to fire IDENTITY_CHANGED: %s', _ev_err)
+
         logger.info('DDNS config updated: domain_mode=%r domain_name=%r', domain_mode, domain_name)
         return jsonify({'updated': True})
     except Exception as e:
@@ -660,12 +658,12 @@ def cancel_pending_config():
         if cur_cell_name and old_cell_name and cur_cell_name != old_cell_name:
             network_manager.apply_cell_name(cur_cell_name, old_cell_name, reload=False)
 
-        if _id.get('domain_mode', 'lan') == 'lan':
-            _ip_revert.write_caddyfile(
-                _id.get('ip_range', os.environ.get('CELL_IP_RANGE', '172.20.0.0/16')),
-                _id.get('cell_name', os.environ.get('CELL_NAME', 'mycell')),
-                _dom, '/app/config-caddy/Caddyfile'
-            )
+        # Regenerate Caddyfile for the reverted identity (all domain modes)
+        try:
+            from app import caddy_manager as _cm
+            _cm.regenerate_with_installed([])
+        except Exception as _cm_err:
+            logger.warning('cancel_pending_config: caddy regenerate failed (non-fatal): %s', _cm_err)
 
     _clear_pending_restart()
     return jsonify({'message': 'Pending changes discarded'})