最近在用SpringBoot2.0和redis搞分布式session,涉及到从response中取出session的token值,这个方法每次都要在controller中传入HttpServletResponse对象,以及硬传入token的值,显得比较繁琐,于是想能不能通过Spring直接解析出request中附带的token值,然后直接在controller中传入pojo对象,即将解析的代码提取出来,于是找到了相应的方法.
首先新建一个类实现WebMvcConfigurationSupport,在SpringBoot2.0或Spring5以下的版本也可以实现WebMvcConfigurerAdapter(新版本已废弃)
@Configuration
public class WebConfig extends WebMvcConfigurationSupport {
@Autowired
private UserArgumentResolver resolver;
@Override
protected void addArgumentResolvers(List<HandlerMethodArgumentResolver> argumentResolvers) {
argumentResolvers.add(resolver);
super.addArgumentResolvers(argumentResolvers);
}
}
由于我们要写一个自定义的参数解析器,自然就重写他的addArgumentResolvers方法,看这个方法的参数是一个List集合里面的元素是HandlerMethodArgumentResolver,自然我们就要自己写一个,这是个接口.
package cn.paul.spike.config;
import cn.paul.spike.domain.User;
import cn.paul.spike.service.UserService;
import com.alibaba.druid.util.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.MethodParameter;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.method.support.ModelAndViewContainer;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import static cn.paul.spike.service.UserService.COOKIE_NAME_TOKEN;
/**
* @author Paul
* @version 0.1
* @date 2018/3/15 0015
*/
@Component
public class UserArgumentResolver implements HandlerMethodArgumentResolver {
@Autowired
private UserService userService;
@Override
public boolean supportsParameter(MethodParameter parameter) {
Class<?> aClass = parameter.getParameterType();
return aClass == User.class;
}
@Override
public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer, NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception {
HttpServletRequest request = webRequest.getNativeRequest(HttpServletRequest.class);
HttpServletResponse response = webRequest.getNativeResponse(HttpServletResponse.class);
String paramToken = request.getParameter(COOKIE_NAME_TOKEN);
String cookieToken = getCookieValue(request, COOKIE_NAME_TOKEN);
if (StringUtils.isEmpty(cookieToken) && StringUtils.isEmpty(paramToken)) {
return null;
}
String token = StringUtils.isEmpty(paramToken) ? cookieToken : paramToken;
User user = userService.getByToken(response, token);
return user;
}
private String getCookieValue(HttpServletRequest request, String cookieNameToken) {
Cookie[] cookies = request.getCookies();
for (Cookie cookie : cookies) {
if (cookie.getName().equals(cookieNameToken)) {
return cookie.getValue();
}
}
return null;
}
}