Fix: Traefik proxy startup issues - handle null versions and filter predefined networks

Fixes two critical issues preventing Traefik proxy startup:

1. TypeError when restarting proxy: Handle null return from get_traefik_versions()
   - Add null check before dispatching CheckTraefikVersionForServerJob
   - Log warning when version data is unavailable
   - Prevents: "Argument #2 must be of type array, null given"

2. Docker network error: Filter out predefined Docker networks
   - Add isDockerPredefinedNetwork() helper to centralize network filtering
   - Apply filtering in collectDockerNetworksByServer() before operations
   - Apply filtering in generateDefaultProxyConfiguration()
   - Prevents: "operation is not permitted on predefined default network"

Also: Move $cachedVersionsFile assignment after null check in Proxy.php

Tests: Added 7 new unit tests for network filtering function
All existing tests pass with no regressions

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

app/Livewire/Server/Navbar.php

@@ -10,6 +10,7 @@ use App\Jobs\CheckTraefikVersionForServerJob;
 use App\Models\Server;
 use App\Services\ProxyDashboardCacheService;
 use Illuminate\Foundation\Auth\Access\AuthorizesRequests;
+use Illuminate\Support\Facades\Log;
 use Livewire\Component;
 
 class Navbar extends Component
@@ -72,7 +73,15 @@ class Navbar extends Component
 
             // Check Traefik version after restart to provide immediate feedback
             if ($this->server->proxyType() === ProxyTypes::TRAEFIK->value) {
-                CheckTraefikVersionForServerJob::dispatch($this->server, get_traefik_versions());
+                $traefikVersions = get_traefik_versions();
+                if ($traefikVersions !== null) {
+                    CheckTraefikVersionForServerJob::dispatch($this->server, $traefikVersions);
+                } else {
+                    Log::warning('Traefik version check skipped: versions.json data unavailable', [
+                        'server_id' => $this->server->id,
+                        'server_name' => $this->server->name,
+                    ]);
+                }
             }
         } catch (\Throwable $e) {
             return handleError($e, $this);

app/Livewire/Server/Proxy.php

@@ -79,12 +79,11 @@ class Proxy extends Component
 
         // Load from global cached helper (Redis + filesystem)
         $versionsData = get_versions_data();
-        $this->cachedVersionsFile = $versionsData;
-
         if (! $versionsData) {
             return null;
         }
 
+        $this->cachedVersionsFile = $versionsData;
         $traefikVersions = data_get($versionsData, 'traefik');
 
         return is_array($traefikVersions) ? $traefikVersions : null;

bootstrap/helpers/proxy.php

@@ -6,6 +6,20 @@ use App\Models\Application;
 use App\Models\Server;
 use Symfony\Component\Yaml\Yaml;
 
+/**
+ * Check if a network name is a Docker predefined system network.
+ * These networks cannot be created, modified, or managed by docker network commands.
+ *
+ * @param  string  $network  Network name to check
+ * @return bool True if it's a predefined network that should be skipped
+ */
+function isDockerPredefinedNetwork(string $network): bool
+{
+    // Only filter 'default' and 'host' to match existing codebase patterns
+    // See: bootstrap/helpers/parsers.php:891, bootstrap/helpers/shared.php:689,748
+    return in_array($network, ['default', 'host'], true);
+}
+
 function collectProxyDockerNetworksByServer(Server $server)
 {
     if (! $server->isFunctional()) {
@@ -66,8 +80,12 @@ function collectDockerNetworksByServer(Server $server)
         $networks->push($network);
         $allNetworks->push($network);
     }
-    $networks = collect($networks)->flatten()->unique();
-    $allNetworks = $allNetworks->flatten()->unique();
+    $networks = collect($networks)->flatten()->unique()->filter(function ($network) {
+        return ! isDockerPredefinedNetwork($network);
+    });
+    $allNetworks = $allNetworks->flatten()->unique()->filter(function ($network) {
+        return ! isDockerPredefinedNetwork($network);
+    });
     if ($server->isSwarm()) {
         if ($networks->count() === 0) {
             $networks = collect(['coolify-overlay']);
@@ -219,8 +237,8 @@ function generateDefaultProxyConfiguration(Server $server, array $custom_command
     $array_of_networks = collect([]);
     $filtered_networks = collect([]);
     $networks->map(function ($network) use ($array_of_networks, $filtered_networks) {
-        if ($network === 'host') {
-            return; // network-scoped alias is supported only for containers in user defined networks
+        if (isDockerPredefinedNetwork($network)) {
+            return; // Predefined networks cannot be used in network configuration
         }
 
         $array_of_networks[$network] = [

tests/Unit/ProxyHelperTest.php

@@ -153,3 +153,39 @@ it('compares branches for minor upgrades', function () {
 
     expect($result)->toBeTrue();
 });
+
+it('identifies default as predefined network', function () {
+    expect(isDockerPredefinedNetwork('default'))->toBeTrue();
+});
+
+it('identifies host as predefined network', function () {
+    expect(isDockerPredefinedNetwork('host'))->toBeTrue();
+});
+
+it('identifies coolify as not predefined network', function () {
+    expect(isDockerPredefinedNetwork('coolify'))->toBeFalse();
+});
+
+it('identifies coolify-overlay as not predefined network', function () {
+    expect(isDockerPredefinedNetwork('coolify-overlay'))->toBeFalse();
+});
+
+it('identifies custom networks as not predefined', function () {
+    $customNetworks = ['my-network', 'app-network', 'custom-123'];
+
+    foreach ($customNetworks as $network) {
+        expect(isDockerPredefinedNetwork($network))->toBeFalse();
+    }
+});
+
+it('identifies bridge as not predefined (per codebase pattern)', function () {
+    // 'bridge' is technically a Docker predefined network, but existing codebase
+    // only filters 'default' and 'host', so we maintain consistency
+    expect(isDockerPredefinedNetwork('bridge'))->toBeFalse();
+});
+
+it('identifies none as not predefined (per codebase pattern)', function () {
+    // 'none' is technically a Docker predefined network, but existing codebase
+    // only filters 'default' and 'host', so we maintain consistency
+    expect(isDockerPredefinedNetwork('none'))->toBeFalse();
+});