http-client 如何发送json及二进制图片

<?php
use Workerman\Worker;

require_once 'vendor/autoload.php';

$worker = new Worker();
$worker->onWorkerStart = function () {
    $http = new Workerman\Http\Client();
    // 上传文件
    $multipart = new \Workerman\Psr7\MultipartStream([
        [
            'name' => 'file',
            'contents' => fopen(__FILE__, 'r')
        ],
        [
            'name' => 'json',
            'contents' => json_encode(['a'=>1, 'b'=>2])
        ]
    ]);
    $boundary = $multipart->getBoundary();
    $http->request('http://127.0.0.1:8787', [
        'method' => 'POST',
        'version' => '1.1',
        'headers' => ['Connection' => 'keep-alive', 'Content-Type' => "multipart/form-data; boundary=$boundary"],
        'data' => $multipart,
        'success' => function ($response) {
            echo $response->getBody();
        },
        'error' => function ($exception) {
            echo $exception;
        }
    ]);
};

Worker::runAll();

类似这样上传文件