本文内容较多，包括微信接入、获取微信用户信息、微信支付、JSSDK配置参数获取等部分。如果读者对微信开发没有一个主观上的认识，那么建议读者先研读微信公众平台开发者文档，然后再阅读本文，效果更佳！另外本文的分章节版本可以在八宝粥的博客找到。

20160712-Update：微信开发的完整例子已经整理在Github，欢迎查看： yii2-wechat-demo。

接入微信

Yii2后台配置

1.在app/config/params.php中配置token参数

return [
    //微信接入
    'wechat' =>[
        'token' => 'your token',
    ],
];

2.在app/config/main.php中配置路由

因为接口模块使用的RESTful API，所以需要定义路由规则。

'urlManager' => [
    'enablePrettyUrl' => true,
    'enableStrictParsing' => true,
    'showScriptName' => false,
    'rules' => [
        [
            'class' => 'yii\rest\UrlRule',
            'controller' => 'wechat',
            'extraPatterns' => [
                'GET valid' => 'valid',
            ],
        ],
    ],
],

3.在app/controllers中新建WechatController

<?php

namespace api\controllers;

use Yii;
use yii\rest\ActiveController;

class WechatController extends ActiveController
{

    public $modelClass = '';

    public function actionValid()
    {
        $echoStr = $_GET["echostr"];
        $signature = $_GET["signature"];
        $timestamp = $_GET["timestamp"];
        $nonce = $_GET["nonce"];
        //valid signature , option
        if($this->checkSignature($signature,$timestamp,$nonce)){
            echo $echoStr;
        }
    }

    private function checkSignature($signature,$timestamp,$nonce)
    {
        // you must define TOKEN by yourself
        $token = Yii::$app->params['wechat']['token'];
        if (!$token) {
            echo 'TOKEN is not defined!';
        } else {
            $tmpArr = array($token, $timestamp, $nonce);
            // use SORT_STRING rule
            sort($tmpArr, SORT_STRING);
            $tmpStr = implode( $tmpArr );
            $tmpStr = sha1( $tmpStr );

            if( $tmpStr == $signature ){
                return true;
            }else{
                return false;
            }
        }
    }

}

微信公众号后台配置

在微信公众号后台配置URL和Token，然后提交验证即可。

URL:http://app.demo.com/wechats/valid
Token:your token

获取用户信息

用户表设计

CREATE TABLE `wechat_user` (
  `id` int(11) NOT NULL,
  `openid` varchar(255) COLLATE utf8_unicode_ci NOT NULL,
  `nickname` varchar(50) COLLATE utf8_unicode_ci NOT NULL COMMENT '微信昵称',
  `sex` tinyint(4) NOT NULL COMMENT '性别',
  `headimgurl` varchar(255) COLLATE utf8_unicode_ci NOT NULL COMMENT '头像',
  `country` varchar(50) COLLATE utf8_unicode_ci NOT NULL COMMENT '国家',
  `province` varchar(50) COLLATE utf8_unicode_ci NOT NULL COMMENT '省份',
  `city` varchar(50) COLLATE utf8_unicode_ci NOT NULL COMMENT '城市',
  `access_token` varchar(255) COLLATE utf8_unicode_ci NOT NULL,
  `refresh_token` varchar(255) COLLATE utf8_unicode_ci NOT NULL,
  `created_at` timestamp NULL DEFAULT CURRENT_TIMESTAMP
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;

ALTER TABLE `wechat_user`
  ADD PRIMARY KEY (`id`);

获取用户信息的相关接口

1.用户授权接口：获取access_token、openid等；获取并保存用户资料到数据库

public function actionAccesstoken()
{
    $code = $_GET["code"];
    $state = $_GET["state"];
    $appid = Yii::$app->params['wechat']['appid'];
    $appsecret = Yii::$app->params['wechat']['appsecret'];
    $request_url = 'https://api.weixin.qq.com/sns/oauth2/access_token?appid='.$appid.'&secret='.$appsecret.'&code='.$code.'&grant_type=authorization_code';

    //初始化一个curl会话
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $request_url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    $result = curl_exec($ch);
    curl_close($ch);
    $result = $this->response($result);

    //获取token和openid成功，数据解析
    $access_token = $result['access_token'];
    $refresh_token = $result['refresh_token'];
    $openid = $result['openid'];

    //请求微信接口，获取用户信息
    $userInfo = $this->getUserInfo($access_token,$openid);
    $user_check = WechatUser::find()->where(['openid'=>$openid])->one();
    if ($user_check) {
        //更新用户资料
    } else {
        //保存用户资料
    }

    //前端网页的重定向
    if ($openid) {
        return $this->redirect($state.$openid);
    } else {
        return $this->redirect($state);
    }
}

2.从微信获取用户资料

public function getUserInfo($access_token,$openid)
{
    $request_url = 'https://api.weixin.qq.com/sns/userinfo?access_token='.$access_token.'&openid='.$openid.'&lang=zh_CN';
    //初始化一个curl会话
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $request_url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    $result = curl_exec($ch);
    curl_close($ch);
    $result = $this->response($result);
    return $result;
}

3.获取用户资料接口

public function actionUserinfo()
{
    if(isset($_REQUEST["openid"])){
        $openid = $_REQUEST["openid"];
        $user = WechatUser::find()->where(['openid'=>$openid])->one();
        if ($user) {
            $result['error'] = 0;
            $result['msg'] = '获取成功';
            $result['user'] = $user;
        } else {
            $result['error'] = 1;
            $result['msg'] = '没有该用户';
        }
    } else {
        $result['error'] = 1;
        $result['msg'] = 'openid为空';
    }
    return $result;
}

微信支付

1.微信支付接口：打包支付数据

public function actionPay(){
    if(isset($_REQUEST["uid"])&&isset($_REQUEST["oid"])&&isset($_REQUEST["totalFee"])){
        //uid、oid、totalFee
        $uid = $_REQUEST["uid"];
        $oid = $_REQUEST["oid"];
        $totalFee = $_REQUEST["totalFee"];
        $timestamp = time();

        //微信支付参数
        $appid = Yii::$app->params['wechat']['appid'];
        $mchid = Yii::$app->params['wechat']['mchid'];
        $key = Yii::$app->params['wechat']['key'];
        $notifyUrl = Yii::$app->params['wechat']['notifyUrl'];

        //支付打包
        $wx_pay = new WechatPay($mchid, $appid, $key);
        $package = $wx_pay->createJsBizPackage($uid, $totalFee, $oid, $notifyUrl, $timestamp);
        $result['error'] = 0;
        $result['msg'] = '支付打包成功';
        $result['package'] = $package;
        return $result;
    }else{
        $result['error'] = 1;
        $result['msg'] = '请求参数错误';
    }
    return $result;
}

2.接收微信发送的异步支付结果通知

public function actionNotify(){
    $postStr = $GLOBALS["HTTP_RAW_POST_DATA"];
    $postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA);
    //
    if ($postObj === false) {
        die('parse xml error');
    }
    if ($postObj->return_code != 'SUCCESS') {
        die($postObj->return_msg);
    }
    if ($postObj->result_code != 'SUCCESS') {
        die($postObj->err_code);
    }

    //微信支付参数
    $appid = Yii::$app->params['wechat']['appid'];
    $mchid = Yii::$app->params['wechat']['mchid'];
    $key = Yii::$app->params['wechat']['key'];
    $wx_pay = new WechatPay($mchid, $appid, $key);

    //验证签名
    $arr = (array)$postObj;
    unset($arr['sign']);
    if ($wx_pay->getSign($arr, $key) != $postObj->sign) {
        die("签名错误");
    }

    //支付处理正确-判断是否已处理过支付状态
    $orders = Order::find()->where(['uid'=>$postObj->openid, 'oid'=>$postObj->out_trade_no, 'status' => 0])->all();

    if(count($orders) > 0){
        //更新订单状态
        foreach ($orders as $order) {
            //更新订单
            $order['status'] = 1;
            $order->update();
        }
        return '<xml><return_code><![CDATA[SUCCESS]]></return_code><return_msg><![CDATA[OK]]></return_msg></xml>';
    } else {
        //订单状态已更新，直接返回
        return '<xml><return_code><![CDATA[SUCCESS]]></return_code><return_msg><![CDATA[OK]]></return_msg></xml>';
    }
}

3.微信支付类 WechatPay.php

<?php

namespace api\sdk;

use Yii;

class WechatPay
{
    protected $mchid;
    protected $appid;
    protected $key;

    public function __construct($mchid, $appid, $key){
        $this->mchid = $mchid;
        $this->appid = $appid;
        $this->key = $key;
    }

    public function createJsBizPackage($openid, $totalFee, $outTradeNo, $orderName, $notifyUrl, $timestamp){
        $config = array(
            'mch_id' => $this->mchid,
            'appid' => $this->appid,
            'key' => $this->key,
        );
        $unified = array(
            'appid' => $config['appid'],
            'attach' => '支付',
            'body' => $orderName,
            'mch_id' => $config['mch_id'],
            'nonce_str' => self::createNonceStr(),
            'notify_url' => $notifyUrl,
            'openid' => $openid,
            'out_trade_no' => $outTradeNo,
            'spbill_create_ip' => '127.0.0.1',
            'total_fee' => intval($totalFee * 100),
            'trade_type' => 'JSAPI',
        );
        $unified['sign'] = self::getSign($unified, $config['key']);
        $responseXml = self::curlPost('https://api.mch.weixin.qq.com/pay/unifiedorder', self::arrayToXml($unified));
        $unifiedOrder = simplexml_load_string($responseXml, 'SimpleXMLElement', LIBXML_NOCDATA);
        if ($unifiedOrder === false) {
            die('parse xml error');
        }
        if ($unifiedOrder->return_code != 'SUCCESS') {
            die($unifiedOrder->return_msg);
        }
        if ($unifiedOrder->result_code != 'SUCCESS') {
            die($unifiedOrder->err_code);
        }
        $arr = array(
            "appId" => $config['appid'],
            "timeStamp" => $timestamp,
            "nonceStr" => self::createNonceStr(),
            "package" => "prepay_id=" . $unifiedOrder->prepay_id,
            "signType" => 'MD5',
        );
        $arr['paySign'] = self::getSign($arr, $config['key']);
        return $arr;
    }

    public static function curlGet($url = '', $options = array()){
        $ch = curl_init($url);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_TIMEOUT, 30);
        if (!empty($options)) {
            curl_setopt_array($ch, $options);
        }
        //https请求 不验证证书和host
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
        $data = curl_exec($ch);
        curl_close($ch);
        return $data;
    }


    public static function curlPost($url = '', $postData = '', $options = array()){
        if (is_array($postData)) {
            $postData = http_build_query($postData);
        }
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $postData);
        curl_setopt($ch, CURLOPT_TIMEOUT, 30); //设置cURL允许执行的最长秒数
        if (!empty($options)) {
            curl_setopt_array($ch, $options);
        }
        //https请求 不验证证书和host
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
        $data = curl_exec($ch);
        curl_close($ch);
        return $data;
    }

    public static function createNonceStr($length = 16){
        $chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
        $str = '';
        for ($i = 0; $i<$length; $i++){
            $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
        }
        return $str;
    }

    public static function arrayToXml($arr){
        $xml = "<xml>";
        foreach ($arr as $key => $val){
            if (is_numeric($val)) {
                $xml .= "<" . $key . ">" . $val . "</" . $key . ">";
            } else {
                $xml .= "<" . $key . "><![CDATA[" . $val . "]]></" . $key . ">";
            }
        }
        $xml .= "</xml>";
        return $xml;
    }

    public static function getSign($params, $key){
        ksort($params, SORT_STRING);
        $unSignParaString = self::formatQueryParaMap($params, false);
        $signStr = strtoupper(md5($unSignParaString . "&key=" . $key));
        return $signStr;
    }

    protected static function formatQueryParaMap($paraMap, $urlEncode = false){
        $buff = "";
        ksort($paraMap);
        foreach ($paraMap as $k => $v){
            if (null != $v && "null" != $v) {
                if ($urlEncode) {
                    $v = urlencode($v);
                }
                $buff .= $k . "=" . $v . "&";
            }
        }
        $reqPar = '';
        if (strlen($buff)>0) {
            $reqPar = substr($buff, 0, strlen($buff) - 1);
        }
        return $reqPar;
    }

}

获取JS-SDK的config参数

根据微信公众平台开发者文档：

所有需要使用JS-SDK的页面必须先注入配置信息，否则将无法调用（同一个url仅需调用一次，对于变化url的SPA的web app可在每次url变化时进行调用,目前Android微信客户端不支持pushState的H5新特性，所以使用pushState来实现web app的页面会导致签名失败，此问题会在Android6.2中修复）。

即：

wx.config({
    debug: true, // 开启调试模式,调用的所有api的返回值会在客户端alert出来，若要查看传入的参数，可以在pc端打开，参数信息会通过log打出，仅在pc端时才会打印。
    appId: '', // 必填，公众号的唯一标识
    timestamp: , // 必填，生成签名的时间戳
    nonceStr: '', // 必填，生成签名的随机串
    signature: '',// 必填，签名，见附录1
    jsApiList: [] // 必填，需要使用的JS接口列表，所有JS接口列表见附录2
});

1.微信支付类 WechatPay.php

<?php

namespace api\sdk;

use Yii;

class WechatPay
{

    public function getSignPackage($url) {
        $jsapiTicket = self::getJsApiTicket();

        $timestamp = time();
        $nonceStr = self::createNonceStr();

        // 这里参数的顺序要按照 key 值 ASCII 码升序排序
        $string = "jsapi_ticket=".$jsapiTicket."&noncestr=".$nonceStr."&timestamp=".$timestamp."&url=".$url;

        $signature = sha1($string);

        $signPackage = array(
            "appId"     => $this->appid,
            "nonceStr"  => $nonceStr,
            "timestamp" => $timestamp,
            "url"       => $url,
            "signature" => $signature,
            "rawString" => $string
        );
        return $signPackage;
    }

    public static function getJsApiTicket() {
        //使用Redis缓存 jsapi_ticket
        $redis = Yii::$app->redis;
        $redis_ticket = $redis->get('wechat:jsapi_ticket');
        if ($redis_ticket) {
            $ticket = $redis_ticket;
        } else {
            $accessToken = self::getAccessToken();
            $url = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?type=jsapi&access_token=".$accessToken;
            $res = json_decode(self::curlGet($url));
            $ticket = $res->ticket;
            if ($ticket) {
                $redis->set('wechat:jsapi_ticket', $ticket);
                $redis->expire('wechat:jsapi_ticket', 7000);
            }
        }
        return $ticket;
    }

    public static function getAccessToken() {
        //使用Redis缓存 access_token
        $redis = Yii::$app->redis;
        $redis_token = $redis->get('wechat:access_token');
        if ($redis_token) {
            $access_token = $redis_token;
        } else {
            $appid = Yii::$app->params['wechat']['appid'];
            $appsecret = Yii::$app->params['wechat']['appsecret'];
            $url = "https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=".$appid."&secret=".$appsecret;
            $res = json_decode(self::curlGet($url));
            $access_token = $res->access_token;
            if ($access_token) {
                $redis->set('wechat:access_token', $access_token);
                $redis->expire('wechat:access_token', 7000);
            }
        }
        return $access_token;
    }

    public static function curlGet($url = '', $options = array()){
        $ch = curl_init($url);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_TIMEOUT, 30);
        if (!empty($options)) {
            curl_setopt_array($ch, $options);
        }
        //https请求 不验证证书和host
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
        $data = curl_exec($ch);
        curl_close($ch);
        return $data;
    }

    public static function curlPost($url = '', $postData = '', $options = array()){
        if (is_array($postData)) {
            $postData = http_build_query($postData);
        }
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $postData);
        curl_setopt($ch, CURLOPT_TIMEOUT, 30); //设置cURL允许执行的最长秒数
        if (!empty($options)) {
            curl_setopt_array($ch, $options);
        }
        //https请求 不验证证书和host
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
        $data = curl_exec($ch);
        curl_close($ch);
        return $data;
    }

    public static function createNonceStr($length = 16){
        $chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
        $str = '';
        for ($i = 0; $i<$length; $i++){
            $str .= substr($chars, mt_rand(0, strlen($chars) - 1), 1);
        }
        return $str;
    }

}

2.获取config参数接口

public function actionConfig(){
    if (isset($_REQUEST['url'])) {
        $url = $_REQUEST['url'];
        //微信支付参数
        $appid = Yii::$app->params['wechat']['appid'];
        $mchid = Yii::$app->params['wechat']['mchid'];
        $key = Yii::$app->params['wechat']['key'];
        $wx_pay = new WechatPay($mchid, $appid, $key);
        $package = $wx_pay->getSignPackage($url);
        $result['error'] = 0;
        $result['msg'] = '获取成功';
        $result['config'] = $package;
    } else {
        $result['error'] = 1;
        $result['msg'] = '参数错误';
    }
    return $result;
}