SpringBoot基于切面来拦截@PathVariable参数及抛出异常全局处理方法

SpringBoot基于切面来拦截@PathVariable参数及抛出异常全局处理方法

微信小程序的接口验证防止非法请求，登录的时候获取openId生成一个七天有效期token存入redis中。

后续每次请求都需要把token作为参数传给后台接口进行验证，为了方便使用@PathVariable 直接将参数做为路径传过来 不用每一次都添加param参数也方便前端接口的请求。

例如：

@ApiOperation(value = "小程序登录")
@PostMapping("/login")
public AntdResponse login(@RequestParam String username, @RequestParam String password, @RequestParam String openId) throws Exception {
    String st = wxTokenService.passport(username, password);
    //省略。。。。。
    String wxToken = IdUtil.simpleUUID();
    data.put("wxToken", wxToken);
    wxTokenService.saveWxTokenToRedis(wxToken, openId);
    return new AntdResponse().success("登录成功，登录有效期七天").data(data);
}

@ApiOperation(value = "预约订单")
@PostMapping("/{wxToken}/addOrder")
public AntdResponse addOrder(@PathVariable String wxToken, @RequestBody ProductOrderDto productOrderDto){
    String openId = wxTokenService.getOpenIdByWxToken(wxToken);
    orderService.addOrder(openId, productOrderDto);
    return new AntdResponse().success("预约订单成功");
}

为了方便统一验证，基于切面来实现数据的验证。

package cn.pconline.antd.smallshop.interceptor;

import cn.pconline.antd.common.exception.WxTokenException;
import cn.pconline.antd.smallshop.service.IWxTokenService;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.servlet.HandlerMapping;

import javax.servlet.http.HttpServletRequest;
import java.util.Map;

/**
 * @Description 微信小程序登录拦截
 * @Author jie.zhao
 * @Date 2020/10/26 18:08
 */
@Component
@Aspect
public class WxMiniInterceptor {

    @Autowired
    private IWxTokenService wxTokenService;
    
    //这里需要把登录的请求控制器排除出去
    @Pointcut("within (cn.pconline.antd.smallshop.wxmini..*) && !within(cn.pconline.antd.smallshop.wxmini.WxMiniLoginController)")
    public void pointCut() {
    }

    @Around("pointCut()")
    public Object trackInfo(ProceedingJoinPoint joinPoint) throws Throwable {
        ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
        HttpServletRequest request = attributes.getRequest();
        Map pathVariables = (Map) request.getAttribute(HandlerMapping.URI_TEMPLATE_VARIABLES_ATTRIBUTE);
        String wxToken = (String) pathVariables.get("wxToken");
        if (wxToken == null) {
            throw new WxTokenException("微信小程序令牌参数缺失！");
        }
        String openId = wxTokenService.getOpenIdByWxToken(wxToken);
        if (openId == null || "".equals(openId)) {
            throw new WxTokenException("登录失效,请重新登录！");
        }
        return joinPoint.proceed();
    }
}

全局异常处理

@RestControllerAdvice
@Order(value = Ordered.HIGHEST_PRECEDENCE)
public class GlobalExceptionHandler {
    @ExceptionHandler(value = WxTokenException.class)
    @ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
    public AntdResponse handleWxTokenException(WxTokenException e) {
        log.error("微信Token拦截异常信息：", e);
        return new AntdResponse().message(e.getMessage()).code(Code.C500.getCode().toString()).status(ResponseStat.ERROR.getText());
    }
}

package cn.pconline.antd.common.exception;

/**
 * 微信授权token异常
 */
public class WxTokenException extends RuntimeException  {

    private static final long serialVersionUID = -3608667856397125671L;

    public WxTokenException(String message) {
        super(message);
    }
}

这里需要注意的是 WxTokenException 要继承RuntimeException而不是Exception，否则的话会报UndeclaredThrowableException。

java.lang.reflect.UndeclaredThrowableException
    at com.insigmaunited.lightai.controller.UserController$$EnhancerBySpringCGLIB$$e4eb8ece.profile(<generated>)

异常原因:
我们的异常处理类，实际是 动态代理的一个实现。
如果一个异常是检查型异常并且没有在动态代理的接口处声明，那么它将会被包装成UndeclaredThrowableException.
而我们定义的自定义异常，被定义成了检查型异常，导致被包装成了UndeclaredThrowableException
java.lang.reflect.UndeclaredThrowableException的解决