4d_admin_backend/app/Http/Controllers/Admin/Wechat/WechatController.php

<?php

namespace App\Http\Controllers\Admin\Wechat;

use App\Http\Controllers\Controller;
use App\Http\Requests\Admin\PageRequest;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Log;
use Overtrue\LaravelWeChat\EasyWeChat;

class WechatController extends Controller
{

    public function serve(Request $request)
    {
        Log::info('request arrived.'); # 注意：Log 为 Laravel 组件，所以它记的日志去 Laravel 日志看，而不是 EasyWeChat 日志

//        $wechat = EasyWeChat::officialAccount();

        $wechat = app('easywechat.official_account.default');
        $wechat->server->setMessageHandler(function($message){
            return "欢迎关注 overtrue！";
        });

        Log::info('return response.');

        return $wechat->server->serve();
    }
}