简介

JSAPI支付是指商户通过调用微信支付提供的JSAPI接口，在支付场景中调起微信支付模块完成收款。

应用场景

JSAPI支付适用于线下场所、公众号场景和PC网站场景。

商户已有H5商城网站，用户通过消息或扫描二维码在微信内打开网页时，可以调用微信支付完成下单购买的流程。具体操作流程如下：

1.商户下发图文消息或者通过自定义菜单吸引用户点击进入商户网页
2.进入商户网页，用户选择购买，完成选购流程。
3.调起微信支付控件，用户开始输入支付密码
4.密码验证通过，支付成功。商户后台得到支付成功的通知
5.返回商户页面，显示购买成功。该页面由商户自定义
6.微信支付公众号下发支付凭证

接入前准备

直接跳转微信支付商户平台 https://pay.weixin.qq.com/wiki/doc/apiv3/open/pay/chapter2_1.shtml

生成密钥文件：

配置文件：

wx:
  appId: appId
  keyPath: apiclient_key.pem
  certPath: apiclient_cert.pem
  certP12Path: 暂不用
  platformCertPath: platform_cert.pem
  mchId: mchId
  apiKey3: 暂不用
  apiKey: apiKey
  domain: https://hous.exchang.cn
  serialNo: 序列号

pom文件：

<dependency>
     <groupId>com.github.wechatpay-apiv3</groupId>
     <artifactId>wechatpay-java</artifactId>
     <version>0.2.2</version>
 </dependency>

代码：

配置类：

//获取yml中微信配置
@Data
@ConfigurationProperties(prefix = "wx")
public class WechatProperties {

    private String appId;

    private String keyPath;

    private String certPath;

    private String platformCertPath;

    private String mchId;

    private String apiKey;

    private String domain;

    private String serialNo;
}
//配置类
@Configuration
@EnableConfigurationProperties(WechatProperties.class)
public class WechatJsapiConfig {


    private final WechatProperties wechatProperties;

    public WechatJsapiConfig(WechatProperties wechatProperties) {
        this.wechatProperties = wechatProperties;
    }

    @Bean
    public RSAConfig rsaConfig() throws IOException {
        ClassPathResource keyResource = new ClassPathResource(wechatProperties.getKeyPath());
        String apiClientKey = keyResource.getFile().getPath();
        ClassPathResource certResource = new ClassPathResource(wechatProperties.getPlatformCertPath());
        String platformCertResourceKey = certResource.getFile().getPath();
        /*String apiClientKey = wechatProperties.getKeyPath();
//        ClassPathResource certResource = new ClassPathResource(wechatProperties.getPlatformCertPath());
        String platformCertResourceKey = wechatProperties.getPlatformCertPath();*/
        return new RSAConfig.Builder()
                .merchantId(wechatProperties.getMchId())
                .privateKeyFromPath(apiClientKey)
                .merchantSerialNumber(wechatProperties.getSerialNo())
                //平台证书
                .wechatPayCertificatesFromPath(platformCertResourceKey)
                .build();
    }

    @Bean
    public JsapiServiceExtension jsapiService() throws IOException {
        return new JsapiServiceExtension.Builder()
                .config(this.rsaConfig())
                .build();
    }

    @Bean
    public NotificationParser notificationParser() throws IOException{
        ClassPathResource certResource = new ClassPathResource(wechatProperties.getPlatformCertPath());
        String platformCertResourceKey = certResource.getFile().getPath();
        //String platformCertResourceKey = wechatProperties.getPlatformCertPath();
        NotificationConfig config = new RSANotificationConfig.Builder()
                .apiV3Key(wechatProperties.getApiKey())
                .certificatesFromPath(platformCertResourceKey)
                .build();
        // 初始化 NotificationParser
        return new NotificationParser(config);

    }

    @Bean(name = "payRefundService")
    public RefundService refundService() throws IOException {
        return new RefundService.Builder().config(this.rsaConfig()).build();
    }

}

创建支付单：

@Slf4j
@Service
@EnableConfigurationProperties(WechatProperties.class)
public class WechatJsapiPayServiceImpl implements BasePayService {

    @Resource
    private WechatProperties wechatProperties;

    @Resource
    private JsapiServiceExtension jsapiService;

    @Value("${spring.application.name}")
    private String serviceName;

    @Resource
    private MemberDao memberDao;

    @Resource
    private RedisCache redisCache;

    @Resource
    private ShopDao shopDao;


    @Override
    public R<?> paymentOrder(List<Order> orderList) {
        BigDecimal total = orderList.stream().map(Order::getPayAmount).reduce(BigDecimal.ZERO, BigDecimal::add);
        Order order = orderList.get(0);
        Long mId = order.getMId();
        Member member = memberDao.queryById(mId);
        Integer payTotal = total.multiply(BigDecimal.valueOf(100)).intValue();
        PrepayRequest prepayRequest = new PrepayRequest();
        prepayRequest.setAppid(wechatProperties.getAppId());
        prepayRequest.setMchid(wechatProperties.getMchId());
        prepayRequest.setDescription("供应链下单");
        prepayRequest.setOutTradeNo(order.getBatchSn());
        prepayRequest.setNotifyUrl(wechatProperties.getDomain() + "/callback/wechat/pay");
        prepayRequest.setAttach("1");
        prepayRequest.setTimeExpire(this.getTimeExpire());
        Amount amount = new Amount();
        amount.setTotal(payTotal);
        Payer payer = new Payer();
        payer.setOpenid(member.getOpenId());
        prepayRequest.setAmount(amount);
        prepayRequest.setPayer(payer);
        log.info("创建预支付单入参：【{}】", JSONObject.toJSONString(prepayRequest));
        try {
            PrepayWithRequestPaymentResponse response = jsapiService.prepayWithRequestPayment(prepayRequest);
            log.info("创建预支付单并生成二维码成功，出参：【{}】", JSONObject.toJSONString(response));
            //未支付监听
            redisCache.setCacheObject(RedisConstants.ORDER_PAY_RESULT.concat(order.getBatchSn()),
                    JSONObject.toJSONString(response), 10, TimeUnit.MINUTES);
            redisCache.setCacheObject(RedisConstants.ORDER_NOT_PAY_LISTENER.concat(order.getBatchSn()),
                    NumberUtils.INTEGER_ZERO, 10, TimeUnit.MINUTES);
            //发送未支付消息
            redisCache.setCacheObject(RedisConstants.ORDER_MSG_LISTENER.concat(order.getBatchSn()),
                    NumberUtils.INTEGER_ZERO, 2, TimeUnit.MINUTES);
            return R.ok(response);
        } catch (HttpException e) { // 发送HTTP请求失败
            log.error("发送HTTP请求失败:{}", e.getHttpRequest());
            return R.fail("发送HTTP请求失败");
        } catch (ServiceException e) { // 服务返回状态小于200或大于等于300，例如500
            log.error("微信支付返回状态异常，{}", e.getResponseBody());
            return R.fail("微信支付返回状态异常");
        } 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
            log.error("返回类型不合法:{}", e.getMessage());
            return R.fail("返回类型不合法");
        }
    }

    @Override
    public void closeOrder(String outTradeNo) {
        CloseOrderRequest closeOrderRequest = new CloseOrderRequest();
        closeOrderRequest.setMchid(wechatProperties.getMchId());
        closeOrderRequest.setOutTradeNo(outTradeNo);
        jsapiService.closeOrder(closeOrderRequest);
        log.info("订单关闭成功，入参：【{}】", JSONObject.toJSONString(closeOrderRequest));
    }

    @Override
    public Optional<Transaction> getOrderInfo(String outTradeNo) {
        QueryOrderByOutTradeNoRequest request = new QueryOrderByOutTradeNoRequest();
        request.setOutTradeNo(outTradeNo);
        request.setMchid(wechatProperties.getMchId());
        Transaction transaction = jsapiService.queryOrderByOutTradeNo(request);
        if (Objects.isNull(transaction)) {
            return Optional.empty();
        }
        return Optional.of(transaction);
    }
    
    private String getTimeExpire(){
        //过期时间  RFC 3339格式
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssXXX");
        //支付订单过期时间
        return sdf.format(new Date(System.currentTimeMillis() + 1000 * 60 * 5));
    }

}

创建退款单：

@Slf4j
@Service
@EnableConfigurationProperties(WechatProperties.class)
public class WechatRefundServiceImpl implements BaseRefundService {

    @Resource
    private RefundService refundService;

    @Resource
    private WechatProperties wechatProperties;

    @Value("${spring.application.name:scm-ofc-system}")
    private String serviceName;

    @Resource
    private OrderDao orderDao;

    @Resource
    private OrderItemDao orderItemDao;

    @Resource
    private ShopDao shopDao;

    @Override
    public R<?> refundOrder(OrderRefund orderRefund) {
        try {
            BigDecimal refundAmount = orderRefund.getRefundAmount();
            Long orderId = orderRefund.getOrderId();
            Order order = orderDao.queryById(orderId);
            //退款金额
            long refundTotal = refundAmount.multiply(BigDecimal.valueOf(100)).longValue();
            //原支付金额
            String batchSn = order.getBatchSn();
            OrderDTO params = new OrderDTO();
            params.setBatchSn(batchSn);
            List<Order> orders = orderDao.selectOrderList(params);
            BigDecimal officialReceipts = orders.stream().map(Order::getPayAmount).reduce(BigDecimal.ZERO, BigDecimal::add);
            long payTotal = officialReceipts.multiply(BigDecimal.valueOf(100)).longValue();
            //创建微信退款单
            CreateRequest createRequest = new CreateRequest();
            AmountReq amountReq = new AmountReq();
            amountReq.setCurrency("CNY");
            amountReq.setTotal(payTotal);
            amountReq.setRefund(refundTotal);
            createRequest.setOutTradeNo(batchSn);
            createRequest.setAmount(amountReq);
            createRequest.setOutRefundNo(orderRefund.getRefundSn());
            createRequest.setNotifyUrl(wechatProperties.getDomain() + "/" + serviceName +  "/callback/wechat/refund");
            log.info("退款单入参：{}", JSONObject.toJSONString(createRequest));
            Refund refund = refundService.create(createRequest);
            log.info("创建退款单成功：{}", JSONObject.toJSONString(refund));
            if (Objects.isNull(refund)) {
                log.error("退款异常，参数：{}", JSONObject.toJSONString(createRequest));
                return R.fail(500, "退款异常，请求微信返回值为null：参数" + JSONObject.toJSONString(createRequest));
            }
            if (Objects.equals(refund.getStatus(), Status.SUCCESS)) {
                return R.ok(refund);
            }
        } catch (Exception e) {
            log.error("退款异常：{}", e.getMessage());
            return R.fail(500, "退款异常，请求微信报错" + e.getMessage());
        }
        return R.ok();
    }
  }

支付与退款回调

@Slf4j
@Service
public class CallbackServiceImpl implements CallbackService {

    @Resource
    private NotificationParser notificationParser;

    @Resource
    private RedisCache redisCache;

    @Resource
    private OrderService orderService;

    @Resource
    private BillDao billDao;

    @Resource
    private ShopAccountDao shopAccountDao;

    @Resource
    private OrderScmService orderScmService;

    @Resource
    private OrderRefundDao orderRefundDao;

    @Resource
    private ShopSkuService shopSkuService;

    @Resource
    private OrderItemDao orderItemDao;

    @Resource
    private MessageService messageService;


    @Override
    @Transactional(rollbackFor = Exception.class)
    public void wechatPayCallback(HttpServletRequest request, HttpServletResponse response) {
        try {
            log.info("=========================微信native支付回调通知============================");
            Transaction transaction = this.verifyAndDecrypt(request, Transaction.class);
            log.info("验证签名成功：{}", JSONObject.toJSONString(transaction));
            Transaction.TradeStateEnum tradeState = transaction.getTradeState();
            if (!Objects.equals(tradeState, Transaction.TradeStateEnum.SUCCESS)) {
                return;
            }
            String outTradeNo = transaction.getOutTradeNo();
            
            log.info("支付回调执行成功，待支付->待发货");
        } catch (Exception e) {
            log.error("支付回调异常：{}", e.getMessage());
        }
    }

    @Override
    public void wechatRefundCallback(HttpServletRequest request, HttpServletResponse response) {
        log.info("=========================微信native退款回调通知============================");
        RefundNotification refundNotification = this.verifyAndDecrypt(request, RefundNotification.class);
        Status refundStatus = refundNotification.getRefundStatus();
        if (!Objects.equals(refundStatus, Status.SUCCESS)) {
            return;
        }
        //执行退款业务
    }
    
    /**
     * 获取供应链订单id
     * @param data
     * @param orderList
     * @return
     */
    private Map<Long, String> getOrderIdMap(OrderByThirdIdVO data,List<Order> orderList){
        List<OrderSkuDetailVO> skus = data.getSkus();
        Map<String, String> skuOrderIdMap = skus.stream()
                .collect(Collectors.toMap(OrderSkuDetailVO::getSku, OrderSkuDetailVO::getOrderId));
        List<OrderItem> orderItems = orderList.stream().map(Order::getOrderItem).collect(Collectors.toList());
        return orderItems.stream().map(item -> {
            String originId = item.getOriginId();
            String orderId = skuOrderIdMap.get(originId);
            return new DefaultKeyValue<>(item.getOrderId(), orderId);
        }).collect(Collectors.toMap(DefaultKeyValue::getKey, DefaultKeyValue::getValue));
    }


    /**
     * 验证并解密报文
     *
     * @param request
     */
    private <T> T verifyAndDecrypt(HttpServletRequest request, Class<T> clazz) {
        String timestamp = request.getHeader("Wechatpay-Timestamp");
        String nonce = request.getHeader("Wechatpay-Nonce");
        String serialNo = request.getHeader("Wechatpay-Serial");
        String signature = request.getHeader("Wechatpay-Signature");
        String signType = request.getHeader("Wechatpay-Signature-Type");
        String body = this.getBody(request);
        log.info("\n请求头信息:\n" +
                        "Wechatpay-Timestamp：{},\n" +
                        "Wechatpay-Nonce：{},\n" +
                        "Wechatpay-Serial：{},\n" +
                        "Wechatpay-Signature：{},\n" +
                        "Wechatpay-Signature-Type：{},\n" +
                        "body: {}",
                timestamp, nonce, serialNo, signature, signType, body);
        RequestParam requestParam = new RequestParam.Builder()
                .serialNumber(serialNo)
                .nonce(nonce)
                .signature(signature)
                .timestamp(timestamp)
                .signType(signType)
                .body(body)
                .build();
        return notificationParser.parse(requestParam, clazz);
    }

    /**
     * 获取请求体内容
     *
     * @param request
     * @return
     */
    private String getBody(HttpServletRequest request) {
        BufferedReader reader;
        String body = "";
        try {
            reader = request.getReader();
            String line;
            StringBuilder inputString = new StringBuilder();
            while ((line = reader.readLine()) != null) {
                inputString.append(line);
            }
            body = inputString.toString();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return body;
    }

}

以上就是微信jsapi支付的对接，仅供参考