Unable to send large attachment: LargeFileUploadTask and headers

Unable to upload large attachment. In the file Microsoft\Kiota\Abstractions\RequestHeaders, the array_keys function is used, which casts a string to a number. PHP 8.4 on x64 does this.

In the getAll method, it is cast and then an error is returned: Since guzzlehttp/psr7 2.11: Passing int to GuzzleHttp\Psr7\Request::__construct() is deprecated; guzzlehttp/psr7 3.0 requires string|string[].

Instead of array_keys, you must use foreach.

A method with array_keys that casts string to int.

public function getAll(): array
{
    $result = [];
    foreach ($this->headers as $key => $value) {
        $result[$key] = array_keys($value);
    }
    return $result;
}

A method with foreach that works.

public function getAll(): array
{
    $result = [];
    foreach ($this->headers as $key => $value) {
        foreach ($value as $k => $v) {
            $result[$key][] = strval($k);
        }
        //$result[$key] = array_keys($value);
    }
    return $result;
}

After this change, sending large attachments works.

Start in Microsoft\Kiota\Abstractions\RequestHeaders and inspect the getAll method, especially its array_keys handling of header values. Reproduce or verify the large attachment upload path with PHP 8.4 and confirm that getAll returns string header keys and large attachments can be sent without the Guzzle request deprecation.