Xlsx Writer problem with Vapor

[brunomcpena]

This is:

- [X] a bug report
- [ ] a feature request
- [ ] **not** a usage question (ask them on https://stackoverflow.com/questions/tagged/phpspreadsheet or https://gitter.im/PHPOffice/PhpSpreadsheet)

What is the expected behavior?

Download the spreadsheet.

What is the current behavior?

Vapor returns "Internal server error".
It works locally.

AWS Log:
Fatal error: Uncaught Exception: Error encoding runtime JSON response: Malformed UTF-8 characters, possibly incorrectly encoded in /var/task/vendor/laravel/vapor-core/src/Runtime/NotifiesLambda.php:49

Stack trace:
#0 /var/task/vendor/laravel/vapor-core/src/Runtime/NotifiesLambda.php(19): Laravel\Vapor\Runtime\LambdaRuntime->lambdaRequest('http://127.0.0....', Array)
#1 /var/task/vendor/laravel/vapor-core/src/Runtime/LambdaRuntime.php(53): Laravel\Vapor\Runtime\LambdaRuntime->notifyLambdaOfResponse('9701efbf-d000-4...', Array)
#2 /var/task/fpmRuntime.php(88): Laravel\Vapor\Runtime\LambdaRuntime->nextInvocation(Object(Closure))
#3 /var/task/runtime.php(36): require('/var/task/fpmRu...')
#4 /opt/bootstrap.php(6): require('/var/task/runti...')

What are the steps to reproduce?

$writer = new \PhpOffice\PhpSpreadsheet\Writer\Xlsx($spreadsheet);
header('Content-Type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet');
header('Content-Disposition: attachment; filename="filename.xlsx"');
$writer->save('php://output');

What features do you think are causing the issue

• Reader
• Writer
• Styles
• Data Validations
• Formula Calculations
• Charts
• AutoFilter
• Form Elements

Does an issue affect all spreadsheet file formats? If not, which formats are affected?

Xlsx (I tried with Csv and it worked)

Which versions of PhpSpreadsheet and PHP are affected?

I'm using PHP 7.4.30, Laravel Framework 8.83.23 and PhpSpreadsheet 1.24.1

[MarkBaker]

So why do you think this is a problem with PhpSpreadsheet? And not a problem with Vapor (whatever Vapor is)? Your stack trace shows nothing of PhpSpreadsheet?