Security6.2 中的SpEL 表达式应用（权限注解使用）-编程知识

Security6.2 中的SpEL 表达式应用（权限注解使用）

最近学习若依框架，里面的权限注解涉及到了SpEL表达式 @PreAuthorize("@ss.hasPermi('system:user:list')")，若依项目中用的是自己写的方法进行权限处理，也可以只用security 来实现权限逻辑代码，下面写如何用security 实现。

security中 @PreAuthorize("hasPermission(Object target, Object permission)") 的hasPermission方法，是通过PermissionEvaluator实现，默认继承类是DenyAllPermissionEvaluator，所有方法返回false，所以注解后的结果只有拒绝权限；所以继承PermissionEvaluator重写hasPermission即可。

逻辑如下：

1、securityConfig文件上加入注解@EnableMethodSecurity，且引入自定义评估器：CustomPermissionEvaluator

2、编写CustomPermissionEvaluator文件

注：security 6.2.1 中 EnableGlobalMethodSecurity 已弃用，改使用 EnableMethodSecurity 且prePostEnabled为ture,只需添加注解@EnableMethodSecurity 即可

package com.example.securityDemo.config;import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.access.expression.method.DefaultMethodSecurityExpressionHandler;
import org.springframework.security.access.expression.method.MethodSecurityExpressionHandler;
import org.springframework.security.config.annotation.method.configuration.EnableMethodSecurity;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.core.userdetails.User;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.security.core.userdetails.UserDetailsService;
import org.springframework.security.provisioning.InMemoryUserDetailsManager;
import org.springframework.security.web.SecurityFilterChain;/*** @description: security配置类* @author: mml* @create: 2024/01/26*/
@Configuration
@EnableWebSecurity
@EnableMethodSecurity
public class SecurityConfig {// 引入自定义评估器@Beanstatic MethodSecurityExpressionHandler methodSecurityExpressionHandler(CustomPermissionEvaluator permissionEvaluator) {DefaultMethodSecurityExpressionHandler handler = new DefaultMethodSecurityExpressionHandler();handler.setPermissionEvaluator(permissionEvaluator);return handler;}@BeanUserDetailsService userDetailsService(){UserDetails user = User.withDefaultPasswordEncoder().username("mml").password("123").roles("USER").authorities("system:user:update","system:user:list").build();return new InMemoryUserDetailsManager(user);}/*** 是Spring Security 过滤器链，Spring Security 中的所有功能都是通过这个链来提供的* @date 2024/1/26*/@BeanSecurityFilterChain securityFilterChain(HttpSecurity httpSecurity) throws Exception {// 拦截所有请求，但是不经过任何过滤器
//        return new DefaultSecurityFilterChain(new AntPathRequestMatcher("/**"));httpSecurity.authorizeHttpRequests(p -> p.anyRequest().authenticated()).csrf(c -> c.disable()).formLogin((form) -> form.loginPage("/login").permitAll());return httpSecurity.build();}}

自定义评估器代码

import org.springframework.security.access.PermissionEvaluator;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.stereotype.Component;
import org.springframework.util.AntPathMatcher;import java.io.Serializable;
import java.util.Collection;/*** @description: 自定义权限评估器* @author: mml* @create: 2024/02/17*/
@Component
public class CustomPermissionEvaluator implements PermissionEvaluator {AntPathMatcher antPathMatcher = new AntPathMatcher();@Overridepublic boolean hasPermission(Authentication authentication, Object targetDomainObject, Object permission) {// 获取当前用户的角色Collection<? extends GrantedAuthority> authorities = authentication.getAuthorities();for (GrantedAuthority authority : authorities) {// 权限判断if (antPathMatcher.match(authority.getAuthority(), (String) permission)){// 说明有权限return true;}}return false;}@Overridepublic boolean hasPermission(Authentication authentication, Serializable targetId, String targetType, Object permission) {return false;}
}

接口层：

@RestController
public class UserController {@RequestMapping("/list")@PreAuthorize("hasPermission('/list','system:user:list')")public String list() {return "get list ";}@RequestMapping("/add")@PreAuthorize("hasPermission('/add','system:user:add')")public String add() {return "post add ";}
}

可以使用postman测试

测试结果如下：

list-有权限