java微信小程序支付-回调（Jsapi-APIv3）

àì夳堔傛蜴生んèń 2023-10-09 21:14 1阅读 0赞

### 一、接入前准备，按照这个文档准备 ###

准备： [接入前准备-小程序支付 | 微信支付商户平台文档中心][-_ _]

准备好了就可以获得(第二点里需要的参数)：  
参数1 商户号 merchantId:xxxxxx(全是数字)

参数2 商户APIV3密钥 apiV3key：xxxxxxx（32位字母数字大小写串，开发自己准备的）

参数3 商户证书序列号 merchantSerialNumber：xxxxx

[查看方式：微信支付证书序列号在哪里看（v3商户证书序列号在哪里查找）-李飞SEO][v3_-_SEO]

参数4 商户API私钥路径 privateKeyPath：apiclient\_key.pem的文件路径

\---------------------Native (二维码)支付下单，前四个就够了，5是用于Jsapi支付----------------  
参数5 国密的微信支付平台证书路径(X509文件) wechatPayCertificatePath:wechatpay\_xxxx.pem()

这个文件找了好久，最后试用下边这个工具下下来可以用[GitHub - wechatpay-apiv3/CertificateDownloader: Java 微信支付 APIv3 平台证书的命令行下载工具][GitHub - wechatpay-apiv3_CertificateDownloader_ Java _ APIv3]

## 二、支付代码接入 ##

支付-官网文档：[https://pay.weixin.qq.com/wiki/doc/api/wxa/wxa\_api.php?chapter=7\_7][https_pay.weixin.qq.com_wiki_doc_api_wxa_wxa_api.php_chapter_7_7]

微信给apiv3做了个maven包，终于像个样子了，结果我发现里边native支付例子虽然完整，但是第一大点里的1-5个参数完全不知道怎么给，jsapi参数同理，我是的东拼西凑凑齐了。maven包文档

[\-][-]

贴一个jsapi的调用例子，小程序端唤起支付用它就够了，这是在官方的例子基础上补全了：

import com.alibaba.fastjson.JSONObject;
    import com.wechat.pay.java.core.Config;
    import com.wechat.pay.java.core.RSAConfig;
    import com.wechat.pay.java.core.exception.HttpException;
    import com.wechat.pay.java.core.exception.MalformedMessageException;
    import com.wechat.pay.java.core.exception.ServiceException;
    import com.wechat.pay.java.service.payments.jsapi.JsapiServiceExtension;
    import com.wechat.pay.java.service.payments.jsapi.model.CloseOrderRequest;
    import com.wechat.pay.java.service.payments.jsapi.model.Payer;
    import com.wechat.pay.java.service.payments.jsapi.model.PrepayRequest;
    import com.wechat.pay.java.service.payments.jsapi.model.PrepayWithRequestPaymentResponse;
    import com.wechat.pay.java.service.payments.jsapi.model.QueryOrderByIdRequest;
    import com.wechat.pay.java.service.payments.jsapi.model.QueryOrderByOutTradeNoRequest;
    import com.wechat.pay.java.service.payments.model.Transaction;
    import com.wechat.pay.java.service.payments.jsapi.model.Amount;
    import lombok.extern.slf4j.Slf4j;
    
    @Slf4j
    public class JsapiDemoService {
        public static String merchantId = "1xxxx";
    //    public static String privateKeyPath = "";
        public static String merchantSerialNumber = "xxxx";
        public static String wechatPayCertificatePath = "";
    
        public static com.wechat.pay.java.service.payments.jsapi.JsapiServiceExtension service;
    
        public static PrepayWithRequestPaymentResponse createWxJsapOrder(String certificatePath, String keyPath, JsapiReq cliReq) {
            String method = Thread.currentThread().getStackTrace()[1].getMethodName();
    
            // 使用自动更新平台证书的RSA配置
            // 一个商户号只能初始化一个配置，否则会因为重复的下载任务报错
            Config config =
                    new RSAConfig.Builder()
                            .merchantId(merchantId)
                            // 使用 com.wechat.pay.java.core.util 中的函数从本地文件中加载商户私钥，商户私钥会用来生成请求的签名
                            .privateKeyFromPath(keyPath)
                            .merchantSerialNumber(merchantSerialNumber)
                            .wechatPayCertificatesFromPath(certificatePath)
                            .build();
            // 构建service
            JsapiServiceExtension service = new JsapiServiceExtension.Builder().config(config).build();
            // request.setXxx(val)设置所需参数，具体参数可见Request定义
            PrepayRequest request = new PrepayRequest();
    
            Payer payer = new Payer();
            payer.setOpenid(cliReq.getOpenid());
            request.setPayer(payer);
    
            Amount amount = new Amount();
            amount.setTotal(10);//订单总金额，单位为分
            request.setAmount(amount);
    
            request.setAppid("wxddddxxxxxx");
            request.setMchid("1xxxx");
            request.setDescription("ms");
            request.setNotifyUrl("https://xxx.net/callBackr");
            //request.setOutTradeNo("out_trade_no_1");
            request.setOutTradeNo(cliReq.getOutTradeNo());
            // 调用下单方法，得到应答
            try {
                // ... 调用接口
                PrepayWithRequestPaymentResponse response = service.prepayWithRequestPayment(request);
                // 使用微信扫描 code_url 对应的二维码，即可体验Native支付
                System.out.println(JSONObject.toJSON(response));
                return response;
            } catch (HttpException e) { // 发送HTTP请求失败
                // 调用e.getHttpRequest()获取请求打印日志或上报监控，更多方法见HttpException定义
                log.error(method, e);
            } catch (ServiceException e) { // 服务返回状态小于200或大于等于300，例如500
                // 调用e.getResponseBody()获取返回体打印日志或上报监控，更多方法见ServiceException定义
                log.error(method, e);
            } catch (MalformedMessageException e) { // 服务返回成功，返回体类型不合法，或者解析返回体失败
                // 调用e.getMessage()获取信息打印日志或上报监控，更多方法见MalformedMessageException定义
                log.error(method, e);
            } catch (Exception e) { // 服务返回成功，返回体类型不合法，或者解析返回体失败
                // 调用e.getMessage()获取信息打印日志或上报监控，更多方法见MalformedMessageException定义
                log.error(method, e);
            }
            return new PrepayWithRequestPaymentResponse();
        }
    
        /** 关闭订单 */
        public static void closeOrder() {
    
            CloseOrderRequest request = new CloseOrderRequest();
            // 调用request.setXxx(val)设置所需参数，具体参数可见Request定义
            // 调用接口
            service.closeOrder(request);
        }
        /** JSAPI支付下单，并返回JSAPI调起支付数据 */
        public static PrepayWithRequestPaymentResponse prepayWithRequestPayment() {
            PrepayRequest request = new PrepayRequest();
            // 调用request.setXxx(val)设置所需参数，具体参数可见Request定义
            // 调用接口
            return service.prepayWithRequestPayment(request);
        }
        /** 微信支付订单号查询订单 */
        public static Transaction queryOrderById() {
    
            QueryOrderByIdRequest request = new QueryOrderByIdRequest();
            // 调用request.setXxx(val)设置所需参数，具体参数可见Request定义
            // 调用接口
            return service.queryOrderById(request);
        }
        /** 商户订单号查询订单 */
        public static Transaction queryOrderByOutTradeNo() {
    
            QueryOrderByOutTradeNoRequest request = new QueryOrderByOutTradeNoRequest();
            // 调用request.setXxx(val)设置所需参数，具体参数可见Request定义
            // 调用接口
            return service.queryOrderByOutTradeNo(request);
        }
    }

补下JsapiReq 的定义

public class JsapiReq implements Serializable {
        private static final long serialVersionUID = 1L;
        private String openid;
        private String outTradeNo;
    }

另外记一下java/spring/srpingboot里resource文件读取路径的方法

String userDir = System.getProperty("user.dir");
            String certificatePath = userDir + "/src/main/resources/cert/wechatpay_xxx.pem";
            String keyPath = userDir + "/src/main/resources/cert/apiclient_xxxxkey.pem";

## 三、支付回调 ##

支付回调-官网文档：[微信支付-开发者文档][- 1]

代码

@PostMapping(value = "/callBack")
        public Map<String, String> callBack(@RequestBody JSONObject jsonObject) {
            String method = Thread.currentThread().getStackTrace()[1].getMethodName();
    
            try {
                String key = WxNativePayProxy.getWxV3Key();
                String json = jsonObject.toString();
                String associated_data = (String) JSONUtil.getByPath(JSONUtil.parse(json), "resource.associated_data");
                String ciphertext = (String) JSONUtil.getByPath(JSONUtil.parse(json), "resource.ciphertext");
                String nonce = (String) JSONUtil.getByPath(JSONUtil.parse(json), "resource.nonce");
    
                String decryptData = new AesUtil(key.getBytes(StandardCharsets.UTF_8)).decryptToString(associated_data.getBytes(StandardCharsets.UTF_8), nonce.getBytes(StandardCharsets.UTF_8), ciphertext);
                //验签成功
                JSONObject decryptDataObj = JSONObject.parseObject(decryptData, JSONObject.class);            
                //decryptDataObj 为解码后的obj，其内容如下。之后便是验签成功后的业务处理
                //{
                //	"sp_appid": "wx8888888888888888",
                //	"sp_mchid": "1230000109",
                //	"sub_appid": "wxd678efh567hg6999",
                //	"sub_mchid": "1900000109",
                //	"out_trade_no": "1217752501201407033233368018",
                //	"trade_state_desc": "支付成功",
                //	"trade_type": "MICROPAY",
                //	"attach": "自定义数据",
                //	"transaction_id": "1217752501201407033233368018",
                //	"trade_state": "SUCCESS",
                //	"bank_type": "CMC",
                //	"success_time": "2018-06-08T10:34:56+08:00",
                //    ...
                //	"payer": {
                //		"openid": "oUpF8uMuAJO_M2pxb1Q9zNjWeS6o"
                //	},
                //	"scene_info": {
                //		"device_id": "013467007045764"
                //	}
                //}
            }catch (Exception e){
                log.info("{} ,parms{}, 异常:", method, jsonObject.toJSONString(), e);
            }
    
            Map<String, String> res = new HashMap<>();
            res.put("code", "SUCCESS");
            res.put("message", "成功");
            return res;
        }

其中有用到微信解码工具类:AesUtil

import java.io.IOException;
    import java.security.GeneralSecurityException;
    import java.security.InvalidAlgorithmParameterException;
    import java.security.InvalidKeyException;
    import java.security.NoSuchAlgorithmException;
    import java.util.Base64;
    import javax.crypto.Cipher;
    import javax.crypto.NoSuchPaddingException;
    import javax.crypto.spec.GCMParameterSpec;
    import javax.crypto.spec.SecretKeySpec;
    
    public class AesUtil{
    
        static final int KEY_LENGTH_BYTE = 32;
        static final int TAG_LENGTH_BIT = 128;
        private final byte[] aesKey;
    
        public AesUtil(byte[] key) {
            if (key.length != KEY_LENGTH_BYTE) {
                throw new IllegalArgumentException("无效的ApiV3Key，长度必须为32个字节");
            }
            this.aesKey = key;
        }
    
        public String decryptToString(byte[] associatedData, byte[] nonce, String ciphertext)
                throws GeneralSecurityException, IOException {
            try {
                Cipher cipher = Cipher.getInstance("AES/GCM/NoPadding");
    
                SecretKeySpec key = new SecretKeySpec(aesKey, "AES");
                GCMParameterSpec spec = new GCMParameterSpec(TAG_LENGTH_BIT, nonce);
    
                cipher.init(Cipher.DECRYPT_MODE, key, spec);
                cipher.updateAAD(associatedData);
    
                return new String(cipher.doFinal(Base64.getDecoder().decode(ciphertext)), "utf-8");
            } catch (NoSuchAlgorithmException | NoSuchPaddingException e) {
                throw new IllegalStateException(e);
            } catch (InvalidKeyException | InvalidAlgorithmParameterException e) {
                throw new IllegalArgumentException(e);
            }
        }
    }

[-_ _]: https://pay.weixin.qq.com/wiki/doc/apiv3/open/pay/chapter2_8_1.shtml
[v3_-_SEO]: https://blog.websem.cc/7104.html
[GitHub - wechatpay-apiv3_CertificateDownloader_ Java _ APIv3]: https://github.com/wechatpay-apiv3/CertificateDownloader
[https_pay.weixin.qq.com_wiki_doc_api_wxa_wxa_api.php_chapter_7_7]: https://pay.weixin.qq.com/wiki/doc/api/wxa/wxa_api.php?chapter=7_7
[-]: https://github.com/wechatpay-apiv3/wechatpay-java
[- 1]: https://pay.weixin.qq.com/wiki/doc/apiv3_partner/apis/chapter4_1_5.shtml