Export CSV low memory fingerprint using iterator - HTTP Streamed Response & CLI

export-csv-stdout.php

<?php 

function csvToStdOut(array $headers, iterable $rows, string $delimiter = ','): void
{
    $resource = fopen('php://output', 'wb');

    fputcsv($resource, $headers, $delimiter);
    foreach ($rows as $row) {
        fputcsv($resource, $row, $delimiter);
    }

    fclose($resource);
}

$generator = function() {
    foreach($names as $name) {
        yield [
            $name,
        ];
    }
}

csvToStdOut(['name'], $generator());

export-csv-streamed-http.php

<?php

use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpFoundation\ResponseHeaderBag;
use Symfony\Component\HttpFoundation\StreamedResponse;

function createStreamedResponseCSV(string $filename, array $headers, iterable $rows, string $delimiter = ','): Response
{
    $response = new StreamedResponse(function () use ($headers, $generator) {
        $resource = fopen('php://output', 'wb');
        fputcsv($resource, $headers, $delimiter);
        foreach ($rows as $row) {
            fputcsv($resource, $row, $delimiter);
        }

        fclose($resource);
    });

    $disposition = $response->headers->makeDisposition(
        ResponseHeaderBag::DISPOSITION_INLINE,
        $filename
    );

    $response->headers->set('Content-Disposition', $disposition);
    $response->headers->set('Content-Encoding', 'none');
    $response->headers->set('Content-Type', 'text/csv; charset=UTF-8');

    return $response;
}

$generator = function() {
    foreach($names as $name) {
        yield [
            $name,
        ];
    }
}

$response = createStreamedResponseCSV('export.csv', ['name'], $generator());