这里有一个关于它如何工作的例子。使用这个来调整你的代码：

use Symfony\Component\Mime\Part\TextPart;
use Symfony\Component\Mime\Multipart\MultipartStream;
use Symfony\Component\Mime\Multipart\FormDataPart;

private function request(string $url, string $method, array $options = [], string $token): ResponseInterface
{
    $endpoint        = $_ENV['FILE_ENDPOINT'];
    $multipartStream = new MultipartStream();

    foreach ($options as $name => $value) {
        $multipartStream->addPart(new TextPart($value, 'form-data', ['name' => $name]));
    }

    $fileContents = 'Contenu du fichier'; // Remplacez cela par le contenu réel du fichier
    $formData = new FormDataPart($fileContents);
    $formData->headers->set('Content-Disposition', 'form-data; name="file"; filename="filename.txt"');
    $multipartStream->addPart($formData);

    $headers = [
        'Authorization' => "Bearer $token",
    ];

    return $this->httpClient->request(
        $method,
        $endpoint . $url,
        [
            'headers' => $headers,
            'body' => $multipartStream->toIterable(),
        ]
    );
}

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