Integrating EasyWeChat SDK for Secure OAuth in PHP Applications

Introduction

EasyWeChat is an open‑source, unofficial SDK for the WeChat platform. It can be installed via Composer in any PHP project.

Environment Requirements

PHP >= 7.4

cURL extension

OpenSSL extension

SimpleXML extension

fileinfo extension

Installation

composer require overtrue/wechat:~5.0 -vvv

OAuth 2.0 Overview

OAuth 2.0 is an open standard for delegated authorization.

OAuth Flow Steps

User opens client and requests authorization.

User grants permission.

Client exchanges the grant for an access token.

Authorization server validates and issues the token.

Client uses the token to request resources.

Resource server validates the token and returns the resources.

Configuration File

Create config/wechat.php with the following array:

<?php
declare(strict_types=1);
return [
    'debug'   => true,
    'app_id'  => 'wxdxxxxxxxxx',
    'secret'  => 'c5xxxxxxxxxx',
    'token'   => '',
    'aes_key' => '',
    'log' => [
        'level'      => 'debug',
        'permission' => 0777,
        'file'       => runtime_path() . '/logs/easywechat.log',
    ],
    'oauth' => [
        'scopes'   => ['snsapi_userinfo'],
        'callback' => 'http://www.example.com/gateway/oauth/wechat-callback',
    ],
];

Singleton Wrapper

Define a singleton class WechatOfficialAccount.php to obtain the EasyWeChat OfficialAccount application instance:

<?php
declare(strict_types=1);
namespace wechat;

use EasyWeChat\\OfficialAccount\\Application;

class WechatOfficialAccount
{
    /** @var Application|null */
    protected static ?Application $instance = null;

    private function __construct() {}

    public static function getInstance(): ?Application
    {
        if (self::$instance === null) {
            self::$instance = \EasyWeChat\\Factory::officialAccount(config('wechat'));
        }
        return self::$instance;
    }

    private function __clone()
    {
        trigger_error('Clone is not allowed', E_USER_ERROR);
    }

    private function __wakeup() {}
}

Authorization Initiation

public function wechatOauth(): Response
{
    $redirectUrl = \wechat\\WechatOfficialAccount::getInstance()->oauth->redirect();
    return redirect($redirectUrl);
}

Authorization Callback

public function wechatCallback(Request $request): Response
{
    $user = WechatOfficialAccount::getInstance()
        ->oauth->userFromCode($request->get('code'));

    $oauthRes = OauthUserModel::where('uuid', $uuid)->findOrEmpty();

    if ($oauthRes->isEmpty()) {
        $oauthRes = OauthUserModel::create([
            'openid'        => $user->getId(),
            'username'      => $user->getName(),
            'nickname'      => $user->getNickname(),
            'avatar'        => $user->getAvatar(),
            'login_ip'      => $request->getRealIp(),
            'account_amount'=> 0,
            'account_score' => 1000,
            'form'          => 1,
        ]);
    } else {
        $updateTime = time();
        OauthUserModel::update([
            'id'          => $oauthRes['id'],
            'update_time' => $updateTime,
            'login_ip'    => $request->getRealIp(),
        ]);
        $oauthRes['update_time'] = $updateTime;
    }

    return redirect('http://www.example.com/test/wechat?openid=' . $oauthRes['openid']);
}

Reference

Official EasyWeChat OAuth documentation:

https://easywechat.com/5.x/official-account/oauth.html