OAuth 2.0 Aggregated Login

<?php
require 'vendor/autoload.php';

$um = new UM($appid, $appkey, $callback, $apiurl);

// 1. 生成登录跳转 URL
$state = bin2hex(random_bytes(16));
$loginUrl = $um->login('wx', $state);
header("Location: $loginUrl");

// 2. 回调获取用户信息
$user = $um->callback($_GET['code']);
// => ["openid"=>"oX...", "nickname"=>"张三", "avatar"=>"..."]

// 3. 二次查询
$info = $um->query('wx', $social_uid);