如何在spring security中编写自定义筛选器？

Question

我希望每个请求都能收到一些信息，因此我认为与其为每个请求提供一个函数并分别从请求中获取这些信息，不如使用一个过滤器<所以每一个请求都会通过这个过滤器，我就能得到我想要的
问题是：如何编写自定义筛选器
假设它不像任何预定义的Spring Security过滤器，它是全新的。

Answer 1

只是把这个放在组合中；在超文本传输协议元素中使用自定义过滤器怎么样：

<security:http auto-config="false" ...>
  ...
  <security:custom-filter position="FORM_LOGIN_FILTER" ref="MyCustomFilter" />
</security:http>

Answer 2

您可以使用标准Java过滤器。只需将其放置在web中的身份验证过滤器之后。xml（这意味着它将在过滤器链的后面，并在安全过滤器链之后调用）。

public class CustomFilter implements Filter{

    @Override
    public void destroy() {
        // Do nothing
    }

    @Override
    public void doFilter(ServletRequest req, ServletResponse res,
            FilterChain chain) throws IOException, ServletException {

            HttpServletRequest request = (HttpServletRequest) req;

            Authentication authentication = SecurityContextHolder.getContext().getAuthentication();

            Set<String> roles = AuthorityUtils.authorityListToSet(authentication.getAuthorities());
            if (roles.contains("ROLE_USER")) {
                request.getSession().setAttribute("myVale", "myvalue");
            }

            chain.doFilter(req, res);

    }

    @Override
    public void init(FilterConfig arg0) throws ServletException {
        // Do nothing
    }

}

web.xml片段：

<!-- The Spring Security Filter Chain -->
<filter>
    <filter-name>springSecurityFilterChain</filter-name>
    <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>

<filter-mapping>
    <filter-name>springSecurityFilterChain</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

<!-- Your filter definition -->
<filter>
    <filter-name>customFilter</filter-name>
    <filter-class>com.yourcompany.test.CustomFilter</filter-class>
</filter>
<filter-mapping>
    <filter-name>customFilter</filter-name>
    <url-pattern>/VacationsManager.jsp</url-pattern>
</filter-mapping>

此外，您还可以添加成功登录后将调用的处理程序（您需要扩展SavedRequestAwareAuthenticationSuccessHandler）。看看这里怎么做。我认为这是一个更好的主意

更新：
或者您可以将此筛选器放在安全筛选器的末尾，如下所示：

<security:filter-chain-map>
    <sec:filter-chain pattern="/**"
            filters="
        ConcurrentSessionFilterAdmin, 
        securityContextPersistenceFilter, 
        logoutFilterAdmin, 
        usernamePasswordAuthenticationFilterAdmin, 
        basicAuthenticationFilterAdmin, 
        requestCacheAwareFilter, 
        securityContextHolderAwareRequestFilter, 
        anonymousAuthenticationFilter, 
        sessionManagementFilterAdmin, 
        exceptionTranslationFilter, 
        filterSecurityInterceptorAdmin,
        MonitoringFilter"/> <!-- Your Filter at the End -->
</security:filter-chain-map>

要使用过滤器，您可以使用以下选项：

public class MonitoringFilter extends GenericFilterBean{
@Override
public void doFilter(ServletRequest request, ServletResponse response,
        FilterChain chain) throws IOException, ServletException {
    //Implement this Function to have your filter working
}