Longrunning Laravel Package

Getting Started

Minimal Steps

1. Install the Package:

   composer require google/longrunning
   

   Ensure ext-grpc is installed for gRPC support (recommended for high-throughput scenarios).

2. Set Up Authentication: Use a service account key file (JSON) and configure credentials via the Google\Auth\Credentials class or environment variables:

   use Google\Auth\Credentials\ServiceAccountCredentials;
   use Google\LongRunning\LongRunningClient;
   
   $credentials = ServiceAccountCredentials::fromStream(__DIR__.'/path/to/service-account.json');
   $client = new LongRunningClient(['credentials' => $credentials]);
   

3. First Use Case: Poll an Operation Trigger a GCP operation (e.g., via google/cloud-compute or another GCP SDK) and poll its status:

   $operationName = 'projects/my-project/regions/us-central1/operations/op-123456789';
   $operation = $client->getOperation($operationName);
   
   // Poll until completion with exponential backoff
   $result = $client->pollUntilDone($operation);
   

4. Check Documentation:

   • Google LongRunning API Reference
   • Google Cloud PHP Authentication Guide

Implementation Patterns

Core Workflows

1. Triggering and Polling Operations

• Pattern: Use a GCP SDK (e.g., google/cloud-compute) to start an operation, then poll its status with LongRunningClient.
• Example:

  // Start an operation (e.g., via Compute Engine SDK)
  $instance = $computeClient->instances->insert('my-project', 'my-zone', $config);
  $operationName = $instance->getName();
  
  // Poll the operation
  $operation = $client->getOperation($operationName);
  $result = $client->pollUntilDone($operation);
  

2. Cancelling Operations

• Pattern: Cancel long-running operations programmatically (e.g., user-triggered cancellation in Laravel).
• Example:

  $operationName = 'projects/my-project/regions/us-central1/operations/op-123456789';
  $client->cancelOperation($operationName);
  

3. Listing Operations

• Pattern: List operations for a project/region to monitor batch jobs or debug failures.
• Example:

  $filter = 'region=us-central1';
  $operations = $client->listOperations('projects/my-project', ['filter' => $filter]);
  foreach ($operations as $operation) {
      if ($operation->getStatus() === 'FAILED') {
          // Handle failure (e.g., log, notify user)
      }
  }
  

4. Exponential Backoff Polling

• Pattern: Configure retry settings to optimize API calls and reduce costs.
• Example:

  $client = new LongRunningClient([
      'credentials' => $credentials,
      'retrySettings' => [
          'maxAttempts' => 10,
          'initialBackoff' => 1.0, // seconds
          'maxBackoff' => 60.0,   // seconds
          'backoffFactor' => 2.0,
      ],
  ]);
  

5. Integrating with Laravel Jobs

• Pattern: Use LongRunningClient in Laravel background jobs to poll GCP operations.
• Example:

  use Google\LongRunning\LongRunningClient;
  use Illuminate\Bus\Queueable;
  use Illuminate\Contracts\Queue\ShouldQueue;
  
  class PollGcpOperation implements ShouldQueue
  {
      use Queueable;
  
      protected $operationName;
  
      public function __construct(string $operationName)
      {
          $this->operationName = $operationName;
      }
  
      public function handle(LongRunningClient $client)
      {
          $operation = $client->getOperation($this->operationName);
          $result = $client->pollUntilDone($operation);
          // Process $result (e.g., save to DB, notify user)
      }
  }
  

Integration Tips

1. Dependency Injection

Bind LongRunningClient in Laravel’s service container for easy access:

// config/app.php
'providers' => [
    // ...
    App\Providers\GoogleLongRunningServiceProvider::class,
];

// App\Providers\GoogleLongRunningServiceProvider.php
public function register()
{
    $this->app->singleton(LongRunningClient::class, function ($app) {
        $credentials = ServiceAccountCredentials::fromStream(storage_path('app/gcp-credentials.json'));
        return new LongRunningClient(['credentials' => $credentials]);
    });
}

2. Error Handling

• Catch Google\ApiCore\ApiException for API errors (e.g., invalid operation names, permission denied).
• Use Google\ApiCore\Operation\Operation methods like getError() to inspect failures:

  try {
      $result = $client->pollUntilDone($operation);
  } catch (ApiException $e) {
      $error = $operation->getError();
      logger()->error("GCP Operation Failed: {$error['message']}");
  }
  

3. gRPC vs. REST

• Use gRPC for high-throughput scenarios (e.g., batch operations, >50 concurrent polls). Ensure ext-grpc is installed and configure the client:

  $client = new LongRunningClient([
      'credentials' => $credentials,
      'grpcOptions' => [
          'ssl_target_name_override' => 'your-service-account-id',
      ],
  ]);
  

• Use REST for simplicity or environments where gRPC isn’t feasible.

4. Logging and Debugging

• Enable debug logging to inspect API calls:

  $client = new LongRunningClient([
      'credentials' => $credentials,
      'logger' => new \Monolog\Logger('gcp', [
          new \Monolog\Handler\StreamHandler(storage_path('logs/gcp.log'), \Monolog\Logger::DEBUG),
      ]),
  ]);
  

• Refer to the Debugging Guide for advanced debugging.

5. Partial Success Handling

• Use the partial_success flag in listOperations to handle batch jobs where some resources succeed and others fail:

  $operations = $client->listOperations('projects/my-project', [
      'filter' => 'region=us-central1',
      'partial_success' => true,
  ]);
  

Gotchas and Tips

Pitfalls

1. Authentication Issues

• Gotcha: Incorrect service account permissions or missing IAM roles (e.g., roles/longrunning.operations.getter).
• Fix: Ensure the service account has the required roles for the GCP service (e.g., roles/compute.admin for Compute Engine).
• Tip: Use Google\Auth\Credentials::fromStream() with a JSON key file and validate scopes:

  $credentials = ServiceAccountCredentials::fromStream($keyFilePath)
      ->withQuotaProject('your-project-id')
      ->withScopes([Google_Service_ComputeEngine::CLOUD_PLATFORM]);
  

2. Operation Name Format

• Gotcha: Invalid operation name format (e.g., missing projects/ or regions/).
• Fix: Use the correct format:

  projects/{PROJECT_ID}/regions/{REGION}/operations/{OPERATION_ID}
  

• Tip: Extract operation names from GCP SDK responses (e.g., $instance->getName() in Compute Engine).

3. Polling Timeouts

• Gotcha: Operations stuck in PENDING or RUNNING due to misconfigured polling.
• Fix: Use pollUntilDone() with custom retry settings or implement a watchdog timeout:

  $startTime = time();
  while (true) {
      $operation = $client->getOperation($operationName);
      if ($operation->getDone()) {
          break;
      }
      if (time() - $startTime > 3600) { // 1-hour timeout
          throw new \RuntimeException("Operation timed out");
      }
      sleep(5);
  }
  

4. gRPC Configuration

• Gotcha: gRPC failures due to missing ssl_target_name_override or incorrect channel settings.
• Fix: Configure gRPC options explicitly:

  $client = new LongRunningClient([
      'credentials' => $credentials,
      'grpcOptions' => [
          'ssl_target_name_override' => 'your-service-account-id@your-project-id.iam.gserviceaccount.com