Bref

README.md

Clone https://github.com/mnapoli/bref-symfony-demo

Install aws sam CLI. Update the aws CLI console to the latest version too (I had to ditch the homebrew version and install via pip to get it).

Add the files found in this gist.

Run sam local start-api to test locally.

Create a S3 bucket, set it in the Makefile and run make deploy to deploy (sam validate can help finding errors in the config file).

bootstrap

#!/opt/bin/php -c/opt/php.ini
<?php

use Symfony\Component\Debug\Debug;
use Symfony\Component\Process\Process;

echo 'Cold start' . PHP_EOL;

error_reporting(E_ALL);

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

Debug::enable();

while (true) {
    $process = new Process(['/opt/bin/php', 'index.php']);
    $process->setTimeout(null);
    $process->run();
}

index.php

<?php
declare(strict_types=1);

use App\Kernel;
use Aws\CloudWatch\CloudWatchClient;
use Bref\Bridge\Psr7\RequestFactory;
use Bref\Bridge\Symfony\SymfonyAdapter;
use Bref\Http\LambdaResponse;
use Symfony\Component\Debug\Debug;

ini_set('display_errors', '1');
error_reporting(E_ALL);

$lambdaRuntimeApi = getenv('AWS_LAMBDA_RUNTIME_API');

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

Debug::enable();

$kernel = new Kernel('prod', false);
$kernel->boot();
$symfonyAdapter = new SymfonyAdapter($kernel);

// This seems to be a blocking call
[$event, $invocationId] = waitForEvent($lambdaRuntimeApi);
if ($event === null) {
    exit(0);
}

// Child process
$request = RequestFactory::fromLambdaEvent($event);
$response = $symfonyAdapter->handle($request);
$lambdaResponse = LambdaResponse::fromPsr7Response($response);

success($lambdaRuntimeApi, $invocationId, $lambdaResponse);

exit(0);

function waitForEvent(string $lambdaRuntimeApi): ?array
{
    $ch = curl_init("http://$lambdaRuntimeApi/2018-06-01/runtime/invocation/next");

    curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
    curl_setopt($ch, CURLOPT_FAILONERROR, true);

    $invocationId = '';

    curl_setopt($ch, CURLOPT_HEADERFUNCTION, function ($ch, $header) use (&$invocationId) {
        if (! preg_match('/:\s*/', $header)) {
            return strlen($header);
        }

        [$name, $value] = preg_split('/:\s*/', $header, 2);

        if (strtolower($name) == 'lambda-runtime-aws-request-id') {
            $invocationId = trim($value);
        }

        return strlen($header);
    });

    $body = '';

    curl_setopt($ch, CURLOPT_WRITEFUNCTION, function ($ch, $chunk) use (&$body) {
        $body .= $chunk;

        return strlen($chunk);
    });

    curl_exec($ch);

    if (curl_error($ch)) {
        die('Failed to fetch next Lambda invocation: ' . curl_error($ch) . "\n");
    }

    if ($invocationId == '') {
        die('Failed to determine Lambda invocation ID');
    }

    curl_close($ch);

    if (! $body) {
        die("Empty Lambda invocation response\n");
    }

    $event = json_decode($body, true);

    if (! array_key_exists('requestContext', $event)) {
        fail($lambdaRuntimeApi, $invocationId, 'Event is not an API Gateway request');
        return null;
    }

    return [$event, $invocationId];
}

function success(string $lambdaRuntimeApi, string $invocationId, LambdaResponse $response)
{
    $ch = curl_init("http://$lambdaRuntimeApi/2018-06-01/runtime/invocation/$invocationId/response");

    $response_json = $response->toJson();

    curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'POST');
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_POSTFIELDS, $response_json);
    curl_setopt($ch, CURLOPT_HTTPHEADER, [
        'Content-Type: application/json',
        'Content-Length: ' . strlen($response_json),
    ]);

    curl_exec($ch);
    curl_close($ch);
}

function fail($lambdaRuntimeApi, $invocationId, $errorMessage)
{
    $ch = curl_init("http://$lambdaRuntimeApi/2018-06-01/runtime/invocation/$invocationId/response");

    $response = [];

    $response['statusCode'] = 500;
    $response['body'] = $errorMessage;

    $response_json = json_encode($response);

    curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'POST');
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_POSTFIELDS, $response_json);
    curl_setopt($ch, CURLOPT_HTTPHEADER, [
        'Content-Type: application/json',
        'Content-Length: ' . strlen($response_json),
    ]);

    curl_exec($ch);
    curl_close($ch);
}

Makefile

deploy: optimize package upload
optimize:
	APP_ENV=prod php bin/console cache:clear --no-debug --no-warmup
	APP_ENV=prod php bin/console cache:warmup
package:
	sam package \
        --template-file template.yaml \
        --output-template-file .cloudformation.yaml \
        --s3-bucket <CREATE A BUCKET MANUALLY AND PUT THE BUCKET NAME HERE>
upload:
	sam deploy \
        --template-file .cloudformation.yaml \
        --stack-name bref-symfony-demo \
        --capabilities CAPABILITY_IAM \
        --region us-east-1

template.yaml

AWSTemplateFormatVersion: '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Description: 'Bref Symfony demo'

# More info about Globals: https://github.com/awslabs/serverless-application-model/blob/master/docs/globals.rst
Globals:
    Function:
        Timeout: 10
        MemorySize: 1024

Resources:
    DemoFunction:
        # See https://github.com/awslabs/serverless-application-model/blob/master/versions/2016-10-31.md#awsserverlessfunction
        Type: AWS::Serverless::Function
        Properties:
            FunctionName: 'bref-symfony-demo'
            Description: 'Bref Symfony demo'
            CodeUri: .
            Handler: bref.php
            Runtime: provided
            Layers:
                - 'arn:aws:lambda:us-east-1:416566615250:layer:php-72:4'
            Environment:
                Variables:
                    APP_ENV: prod
                    APP_DEBUG: '0'
                    # This should not be committed but this is just a demo here, DO NOT DO THAT
                    APP_SECRET: '67d829bf61dc5f87a34fd814e2c9f629'
            Events:
                # See https://github.com/awslabs/serverless-application-model/blob/master/versions/2016-10-31.md#api
                HttpRoot:
                    Type: Api
                    Properties:
                        Path: /
                        Method: ANY
                HttpSubPaths:
                    Type: Api
                    Properties:
                        Path: /{proxy+}
                        Method: ANY

Outputs:
    DemoApi:
        Description: "API Gateway endpoint URL for Prod stage"
        Value: !Sub "https://${ServerlessRestApi}.execute-api.${AWS::Region}.amazonaws.com/Prod/"
    DemoFunction:
        Description: "Demo Lambda Function ARN"
        Value: !GetAtt DemoFunction.Arn

i'm getting a 500 response and Error: Runtime failed to start: fork/exec /var/task/bootstrap: permission denied Runtime.ExitError in my Cloudwatch logs, any idea where to start looking to debug?

maybe it's related to the error i get when i do sam local start-api and go to localhost:3000:

An error occurred (InvalidParameterValueException) when calling the GetLayerVersion operation: Invalid Layer name: arn:aws:lambda:us-east-1:416566615250:layer:php-72

I'm also now getting User root is not authorized to perform: lambda:GetLayerVersion on resource: arn:aws:lambda:us-east-1:416566615250:layer:php-72:4 (Service: AWSLambdaInternal; Status Code: 403; Error Code: AccessDeniedException; when I try to create a new stack - in that case I think I might need to create my own layer. Does this mean we'll have to create a PHP layer during deployment rather than sharing a 'supported' one?

just following up - after building my own PHP layer & updating template.yaml with my PHP ARN, I managed to replicate the permission denied error locally. chmod +x bootstrap solved it. I can now deploy a working example 👍