Download CSV in Mezzio Framework (Zend/Laminas) - csv

Question

In Mezzion Framework I have the next Handler:
<?php
namespace Bgc\Handler;
use App\Service\GenerateReportToCSV;
use Bgc\Queue\BGCQueueManager;
use Laminas\Diactoros\Response\TextResponse;
use League\Csv\Writer;
use Psr\Http\Message\ServerRequestInterface;
use Psr\Http\Server\RequestHandlerInterface;
class DownloadBgcReportHandler implements RequestHandlerInterface
{
protected $bgcQManager;
protected $reportToCSV;
public function __construct(BGCQueueManager $bgcQManager, $reportToCSV)
{
$this->bgcQManager = $bgcQManager;
$this->reportToCSV = $reportToCSV;
}
public function handle(ServerRequestInterface $request): TextResponse
{
$queryParams = $request->getQueryParams();
$params = [];
if (isset($queryParams['startDate'])) {
$starDate = new \DateTime($queryParams['startDate']);
$params['startDate'] = $starDate->modify('midnight');
}
if (isset($queryParams['startDate'])) {
$endDate = new \DateTime($queryParams['endDate']);
$params['endDate'] = $endDate->modify('tomorrow');
}
$itemsBGC = $this->bgcQManager->getDataToDownload($params);
$time = time();
$fileName = "bgc-report-$time.csv";
$csv = Writer::createFromFileObject(new \SplFileObject());
$csv->insertOne($this->reportToCSV->getHeadingsBGC());
foreach ($itemsBGC as $item) {
$csv->insertOne($item);
}
return new TextResponse($csv->getContent(), 200, [
'Content-Type' => 'text/csv',
'Content-Transfer-Encoding' => 'binary',
'Content-Disposition' => "attachment; filename='$fileName'"
]);
}
}
I have the below error:
Whoops\Exception\ErrorException: Declaration of Bgc\Handler\DownloadBgcReportHandler::handle(Psr\Http\Message\ServerRequestInterface $request): Laminas\Diactoros\Response\TextResponse must be compatible with Psr\Http\Server\RequestHandlerInterface::handle(Psr\Http\Message\ServerRequestInterface $request): Psr\Http\Message\ResponseInterface in file /home/peter/proyectos/revelations-thena-api/src/Bgc/src/Handler/DownloadBgcReportHandler.php on line 20
I don't know, to create a downloable file. The hadbler works fine with Json. I tried to change from ResponseInterface to TextResponse.
How can I download file CSV?
Thank you

Answer 1

The error you received is telling you that your method signature is not compliant to interface's method signature.
RequestHandlerInterface:
interface RequestHandlerInterface
{
public function handle(ServerRequestInterface $request): ResponseInterface;
}
As you see, the signature states that an object of type ResponseInterface is returned.
You modified the signature:
class DownloadBgcReportHandler implements RequestHandlerInterface
{
public function handle(ServerRequestInterface $request): TextResponse;
}
The signature must be the same, but then you can return the TextResponse without problem (since it extends Laminas\Diactoros\Response, which implements Psr\Http\Message\ResponseInterface)
Just change that and it will works :)

Answer 2

You have modified you handle method, so right now you aren't fulfilling the requirements of the RequestHandlerInterface

Answer 3

Replace the return value for the handler with ResponseInterface enforced in the interface: RequestHandlerInterface
so i think you are best helped with:
<?php
namespace Bgc\Handler;
use App\Service\GenerateReportToCSV;
use Bgc\Queue\BGCQueueManager;
use Laminas\Diactoros\Response;
use Laminas\Diactoros\Stream;
use League\Csv\Writer;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;
use Psr\Http\Server\RequestHandlerInterface;
class DownloadBgcReportHandler implements RequestHandlerInterface
{
protected $bgcQManager;
protected $reportToCSV;
public function __construct(BGCQueueManager $bgcQManager, $reportToCSV)
{
$this->bgcQManager = $bgcQManager;
$this->reportToCSV = $reportToCSV;
}
public function handle(ServerRequestInterface $request): ResponseInterface
{
$queryParams = $request->getQueryParams();
$params = [];
if (isset($queryParams['startDate'])) {
$starDate = new \DateTime($queryParams['startDate']);
$params['startDate'] = $starDate->modify('midnight');
}
if (isset($queryParams['startDate'])) {
$endDate = new \DateTime($queryParams['endDate']);
$params['endDate'] = $endDate->modify('tomorrow');
}
$itemsBGC = $this->bgcQManager->getDataToDownload($params);
$time = time();
$fileName = "bgc-report-$time.csv";
// $csv = Writer::createFromFileObject(new \SplFileObject());
// $csv->insertOne($this->reportToCSV->getHeadingsBGC());
$csv = Writer::createFromString($this->reportToCSV->getHeadingsBGC());
foreach ($itemsBGC as $item) {
$csv->insertOne($item);
}
$body = new Stream($csv->getContent());
return new Response($body, 200, [
'Cache-Control' => 'must-revalidate',
'Content-Disposition' => 'attachment; filename=' . $fileName,
'Content-Length' => strval($body->getSize()),
'Content-Type' => 'text/csv',
'Content-Transfer-Encoding' => 'binary',
'Expires' => '0',
'Pragma' => 'public',
]);
}
}
PS: i have commented the 2 lines in which an empty new \SplFileObject() was used, because the required param $filename was empty (and i did not want to make a decision there) and added a line with Writer::createFromString().