AWS Lambda PHP Integration

Patterns for deploying PHP and Symfony applications on AWS Lambda using the Bref framework.

Overview

Two approaches available:

• Bref Framework - Standard PHP on Lambda with Symfony support, built-in routing, cold start < 2s
• Raw PHP - Minimal overhead, maximum control, cold start < 500ms

Both support API Gateway integration with production-ready configurations.

When to Use

• Creating new Lambda functions in PHP
• Migrating existing Symfony applications to Lambda
• Optimizing cold start performance
• Configuring API Gateway or SQS/SNS event triggers
• Setting up deployment pipelines for PHP Lambda

Instructions

1. Choose Your Approach

2. Project Structure

Symfony with Bref Structure

my-symfony-lambda/
├── composer.json
├── serverless.yml
├── public/
│   └── index.php         # Lambda entry point
├── src/
│   └── Kernel.php        # Symfony Kernel
├── config/
│   ├── bundles.php
│   ├── routes.yaml
│   └── services.yaml
└── templates/

Raw PHP Structure

my-lambda-function/
├── public/
│   └── index.php         # Handler entry point
├── composer.json
├── serverless.yml
└── src/
    └── Services/

3. Implementation

Symfony with Bref:

// public/index.php
use Bref\Symfony\Bref;
use App\Kernel;
use Symfony\Component\HttpFoundation\Request;

require __DIR__.'/../vendor/autoload.php';

$kernel = new Kernel($_SERVER['APP_ENV'] ?? 'dev', $_SERVER['APP_DEBUG'] ?? true);
$kernel->boot();

$bref = new Bref($kernel);
return $bref->run($event, $context);

Raw PHP Handler:

// public/index.php
use function Bref\Lambda\main;

main(function ($event) {
    $path = $event['path'] ?? '/';
    $method = $event['httpMethod'] ?? 'GET';

    return [
        'statusCode' => 200,
        'body' => json_encode(['message' => 'Hello from PHP Lambda!'])
    ];
});

4. Cold Start Optimization

1. Lazy loading - Defer heavy services until needed
2. Disable unused Symfony features - Turn off validation, annotations
3. Optimize composer autoload - Use classmap for production
4. Use Bref optimized runtime - Leverage PHP 8.x optimizations

5. Connection Management

// Cache AWS clients at function level
use Aws\DynamoDb\DynamoDbClient;

class DatabaseService
{
    private static ?DynamoDbClient $client = null;

    public static function getClient(): DynamoDbClient
    {
        if (self::$client === null) {
            self::$client = new DynamoDbClient([
                'region' => getenv('AWS_REGION'),
                'version' => 'latest'
            ]);
        }
        return self::$client;
    }
}

Best Practices

Memory and Timeout

• Memory: Start with 512MB for Symfony, 256MB for raw PHP
• Timeout: Symfony 10-30s for cold start buffer, Raw PHP 3-10s typically sufficient

Dependencies

{
    "require": {
        "php": "^8.2",
        "bref/bref": "^2.0",
        "symfony/framework-bundle": "^6.0"
    },
    "config": {
        "optimize-autoloader": true,
        "preferred-install": "dist"
    }
}

Error Handling

try {
    $result = processRequest($event);
    return [
        'statusCode' => 200,
        'body' => json_encode($result)
    ];
} catch (ValidationException $e) {
    return [
        'statusCode' => 400,
        'body' => json_encode(['error' => $e->getMessage()])
    ];
} catch (Exception $e) {
    error_log($e->getMessage());
    return [
        'statusCode' => 500,
        'body' => json_encode(['error' => 'Internal error'])
    ];
}

Logging

error_log(json_encode([
    'level' => 'info',
    'message' => 'Request processed',
    'request_id' => $context->getAwsRequestId(),
    'path' => $event['path'] ?? '/'
]));

Deployment

Serverless Configuration

# serverless.yml
service: symfony-lambda-api

provider:
  name: aws
  runtime: php-82
  memorySize: 512
  timeout: 20

package:
  individually: true
  exclude:
    - '**/node_modules/**'
    - '**/.git/**'

functions:
  api:
    handler: public/index.php
    events:
      - http:
          path: /{proxy+}