Upload file with basic auth by file_get_contents

gistfile1.php

<?php

$boundary = '--------------------------' . microtime(true);

$header = [
    sprintf("Authorization: Basic %s", base64_encode($username . ':' . $password)),
    "Content-Type: multipart/form-data; boundary=" . $boundary,
];

$file_contents = file_get_contents($file);

$content =  "--" . $boundary."\r\n".
    "Content-Disposition: form-data; name=\"" . 'form[fileUpload]' . "\"; filename=\"" . basename($file) . "\"\r\n" .
    "Content-Type: application/x-gzip\r\n\r\n" .
    $file_contents . "\r\n";

$content .= "--".$boundary."\r\n".
    "Content-Disposition: form-data; name=\"form[name]\"\r\n\r\n".
    "$complect\r\n";

$content .= "--".$boundary."\r\n".
    "Content-Disposition: form-data; name=\"form[format]\"\r\n\r\n".
    "json\r\n";

$content .= "--".$boundary."--\r\n";

$context = stream_context_create([
    'http' => [
        'method' => 'POST',
        'header' => implode("\r\n", $header),
        'content' => $content,
    ]
]);

$result = file_get_contents($url, false, $context);

U r welcome