fix(deploy): explain SSH exit 255 and handle non-map compose services

- Add a hint to failed command messages when the exit code is 255,
  which explains that the SSH connection to the server closed before
  the command finished.
- Return no services from applicationParser and serviceParser when the
  compose `services` key is empty or is not a map, so parsing does not
  fail.
- Move Server::getIp() out of the sshEndpointInUse() docblock, where it
  was misplaced and broke the class.
- Add tests for the SSH hint, for services keys that are not maps, and
  for saved compose variable values that must survive a redeploy
  (#6995).

app/Models/Server.php

@@ -2055,10 +2055,6 @@ $siteAddress {
         return normalizeIpAddress(preg_replace('/[^0-9a-zA-Z.:%-]/', '', (string) $value));
     }
 
-    public function getIp(): Attribute
-    {
-        return Attribute::make(
-            get: function () {
     /**
      * Whether a server of any team already uses this SSH endpoint. The port is part of the endpoint,
      * so servers behind one NAT address with different forwarded SSH ports are different servers.
@@ -2072,6 +2068,10 @@ $siteAddress {
             ->exists();
     }
 
+    public function getIp(): Attribute
+    {
+        return Attribute::make(
+            get: function () {
                 if (isDev()) {
                     return '127.0.0.1';
                 }

app/Traits/ExecuteRemoteCommand.php

@@ -254,7 +254,19 @@ trait ExecuteRemoteCommand
 
         $error = $this->redact_sensitive_info($error);
 
-        return "Command execution failed (exit code {$exitCode}): {$commandText}\nError: {$error}".$this->dockerNetworkGatewayHint($error);
+        return "Command execution failed (exit code {$exitCode}): {$commandText}\nError: {$error}".$this->dockerNetworkGatewayHint($error).$this->sshConnectionLostHint($exitCode);
+    }
+
+    /**
+     * SSH exits with 255 when the connection closes, so the output of the remote command stops without an error.
+     */
+    private function sshConnectionLostHint(int $exitCode): string
+    {
+        if ($exitCode !== 255) {
+            return '';
+        }
+
+        return "\nExit code 255 usually means that the SSH connection to the server closed before the command finished. Check the network between Coolify and the server, and the sshd logs and memory usage of the server, then deploy again.";
     }
 
     /**

bootstrap/helpers/parsers.php

@@ -1161,7 +1161,10 @@ function applicationParser(Application $resource, int $pull_request_id = 0, ?int
     } catch (Exception) {
         return collect([]);
     }
-    $services = data_get($yaml, 'services', collect([]));
+    $services = data_get($yaml, 'services', []);
+    if (! is_array($services)) {
+        return collect([]);
+    }
     $topLevel = collect([
         'volumes' => collect(data_get($yaml, 'volumes', [])),
         'networks' => collect(data_get($yaml, 'networks', [])),
@@ -2431,7 +2434,10 @@ function serviceParser(Service $resource): Collection
     } catch (Exception) {
         return collect([]);
     }
-    $services = data_get($yaml, 'services', collect([]));
+    $services = data_get($yaml, 'services', []);
+    if (! is_array($services)) {
+        return collect([]);
+    }
 
     // Clean up corrupted environment variables from previous parser bugs
     // (keys starting with $ or ending with } should not exist as env var names)

tests/Feature/ApplicationDeploymentComposeParseTest.php

@@ -89,6 +89,8 @@ it('stops the deployment when the Compose file gives no services, instead of wri
             ->implode(''),
     'invalid YAML' => "services:\n  web:\n    image: [nginx\n",
     'an empty services section' => "services: {}\n",
+    'a services key with no value' => "services:\n",
+    'a services key that is not a map' => "services: web\n",
 ]);
 
 it('deploys a Compose file that reuses YAML anchors more than 128 times', function () {

tests/Feature/ComposeVariableEditsSurviveRedeployTest.php

@@ -0,0 +1,120 @@
+<?php
+
+use App\Models\Application;
+use App\Models\Environment;
+use App\Models\Project;
+use App\Models\Server;
+use App\Models\Service;
+use App\Models\StandaloneDocker;
+use App\Models\Team;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Symfony\Component\Yaml\Yaml;
+
+uses(RefreshDatabase::class);
+
+/**
+ * Regression coverage for https://github.com/coollabsio/coolify/issues/6995:
+ * each deployment parses the compose file again, and that parse must not reset the values
+ * that the user saved, or write stale values into the compose file.
+ */
+function composeWithEditableVariables(string $hardcoded): string
+{
+    return <<<YAML
+services:
+  app:
+    image: busybox:latest
+    environment:
+      - SIMPLE=\${SIMPLE}
+      - WITH_DEFAULT=\${WITH_DEFAULT:-from-compose}
+      - REQUIRED=\${REQUIRED:?}
+      - HARDCODED={$hardcoded}
+YAML;
+}
+
+/**
+ * @return array{team: Team, server: Server, destination: StandaloneDocker, environment: Environment}
+ */
+function composeVariableEditsContext(): array
+{
+    $team = Team::factory()->create();
+    $server = Server::factory()->create(['team_id' => $team->id]);
+
+    return [
+        'team' => $team,
+        'server' => $server,
+        'destination' => StandaloneDocker::query()->where('server_id', $server->id)->firstOrFail(),
+        'environment' => Environment::factory()->create(['project_id' => Project::factory()->create(['team_id' => $team->id])->id]),
+    ];
+}
+
+function saveComposeVariable(Application|Service $resource, string $key, string $value): void
+{
+    $resource->environment_variables()->where('key', $key)->firstOrFail()->update(['value' => $value]);
+}
+
+test('a service keeps saved variable values and uses the edited compose file when it is parsed again', function () {
+    $context = composeVariableEditsContext();
+    $service = Service::factory()->create([
+        'server_id' => $context['server']->id,
+        'environment_id' => $context['environment']->id,
+        'destination_id' => $context['destination']->id,
+        'destination_type' => $context['destination']->getMorphClass(),
+        'docker_compose_raw' => composeWithEditableVariables('v1'),
+    ]);
+
+    $service->parse();
+    saveComposeVariable($service, 'SIMPLE', 'user-simple');
+    saveComposeVariable($service, 'WITH_DEFAULT', 'user-default');
+    saveComposeVariable($service, 'REQUIRED', 'user-required');
+
+    $service->refresh();
+    $service->docker_compose_raw = composeWithEditableVariables('v2');
+    $service->save();
+    $service->parse();
+
+    $environment = data_get(Yaml::parse($service->fresh()->docker_compose), 'services.app.environment');
+
+    expect($service->environment_variables()->pluck('value', 'key')->only(['SIMPLE', 'WITH_DEFAULT', 'REQUIRED'])->all())
+        ->toEqual(['SIMPLE' => 'user-simple', 'WITH_DEFAULT' => 'user-default', 'REQUIRED' => 'user-required'])
+        // The compose file keeps the references, so Docker Compose reads the saved values from .env.
+        ->and($environment)->toMatchArray([
+            'SIMPLE' => '${SIMPLE}',
+            'WITH_DEFAULT' => '${WITH_DEFAULT:-from-compose}',
+            'REQUIRED' => '${REQUIRED:?}',
+            'HARDCODED' => 'v2',
+        ]);
+});
+
+test('a compose application keeps saved variable values and writes no stale values when it is parsed again', function () {
+    $context = composeVariableEditsContext();
+    $application = Application::factory()->create([
+        'environment_id' => $context['environment']->id,
+        'destination_id' => $context['destination']->id,
+        'destination_type' => $context['destination']->getMorphClass(),
+        'build_pack' => 'dockercompose',
+        'docker_compose_raw' => composeWithEditableVariables('v1'),
+    ]);
+
+    applicationParser($application);
+    saveComposeVariable($application, 'SIMPLE', 'first');
+    saveComposeVariable($application, 'WITH_DEFAULT', 'first-default');
+    saveComposeVariable($application, 'REQUIRED', 'first-required');
+    applicationParser($application->fresh());
+
+    saveComposeVariable($application, 'SIMPLE', 'second');
+    saveComposeVariable($application, 'WITH_DEFAULT', 'second-default');
+    saveComposeVariable($application, 'REQUIRED', 'second-required');
+    $application->refresh();
+    $application->docker_compose_raw = composeWithEditableVariables('v2');
+    $application->save();
+    $parsedCompose = applicationParser($application->fresh());
+
+    expect($application->environment_variables()->where('is_preview', false)->pluck('value', 'key')->only(['SIMPLE', 'WITH_DEFAULT', 'REQUIRED'])->all())
+        ->toEqual(['SIMPLE' => 'second', 'WITH_DEFAULT' => 'second-default', 'REQUIRED' => 'second-required'])
+        ->and(data_get($parsedCompose, 'services.app.environment'))->toMatchArray([
+            'SIMPLE' => '${SIMPLE}',
+            'WITH_DEFAULT' => '${WITH_DEFAULT:-from-compose}',
+            'REQUIRED' => '${REQUIRED:?}',
+            'HARDCODED' => 'v2',
+        ]);
+});

tests/Feature/DeploymentSensitiveCommandFailureTest.php

@@ -283,6 +283,33 @@ it('does not add the Docker network hint to other failures', function () {
     expect($exception->getMessage())->not->toContain('systemctl restart docker');
 });
 
+it('reports the exit code and explains a lost SSH connection when a command ends with exit code 255', function () {
+    [$job] = makeSensitiveCommandFailureJob();
+
+    Process::fake(['*' => Process::result(errorOutput: '#26 exporting layers', exitCode: 255)]);
+
+    $exception = captureDeploymentException(fn () => $job->execute_remote_command([
+        'command' => 'docker buildx build .',
+    ]));
+
+    expect($exception->getCode())->toBe(255)
+        ->and($exception->getMessage())
+        ->toContain('exit code 255')
+        ->toContain('SSH connection to the server closed');
+});
+
+it('does not add the SSH connection hint to failures of the remote command', function () {
+    [$job] = makeSensitiveCommandFailureJob();
+
+    Process::fake(['*' => Process::result(errorOutput: 'build failed', exitCode: 1)]);
+
+    $exception = captureDeploymentException(fn () => $job->execute_remote_command([
+        'command' => 'docker buildx build .',
+    ]));
+
+    expect($exception->getMessage())->not->toContain('SSH connection');
+});
+
 it('redacts locked values from the error output of failed commands', function () {
     [$job] = makeSensitiveCommandFailureJob([
         ['key' => 'LOCKED_SECRET', 'value' => SENSITIVE_FAILURE_SECRET, 'is_shown_once' => true],

tests/Feature/ServiceParserServicesSectionTest.php

@@ -0,0 +1,34 @@
+<?php
+
+use App\Models\Environment;
+use App\Models\Project;
+use App\Models\Server;
+use App\Models\Service;
+use App\Models\StandaloneDocker;
+use App\Models\Team;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Support\Facades\Bus;
+
+uses(RefreshDatabase::class);
+
+it('returns no services when the services key of a service stack is not a map', function (string $compose) {
+    Bus::fake();
+    $team = Team::factory()->create();
+    $server = Server::factory()->create(['team_id' => $team->id]);
+    $destination = StandaloneDocker::where('server_id', $server->id)->firstOrFail();
+    $project = Project::factory()->create(['team_id' => $team->id]);
+    $environment = Environment::factory()->create(['project_id' => $project->id]);
+
+    $service = Service::factory()->create([
+        'docker_compose_raw' => $compose,
+        'environment_id' => $environment->id,
+        'server_id' => $server->id,
+        'destination_id' => $destination->id,
+        'destination_type' => $destination->getMorphClass(),
+    ]);
+
+    expect(serviceParser($service))->toBeEmpty();
+})->with([
+    'no value' => "services:\n",
+    'a string' => "services: web\n",
+]);