SpringBoot集成JWT实现token验证（注解过滤）

使用注解统一拦截的方式！ 能简的都简了！

JWT的主要应用场景

单点登录，安全性比较高，签名的密钥是项目自己定的，别人就很难解密！可以确保发送者发送的信息是没有经过伪造的。

说说在前端的使用叭，前端在登录成功后把token存起来(cookie/Storage)统一管理，在请求后端接口时把token带上就ok

SpringBoot和JWT的集成

1、引入JWT依赖

<dependency>
      <groupId>com.auth0</groupId>
      <artifactId>java-jwt</artifactId>
      <version>3.4.0</version>
</dependency>

2、自定义两个注解

2.1 用于跳过验证的PassToken的注解(如登录接口)

@Target({ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface PassToken {
    boolean required() default true;
}

2.2 需登录并验证token的注解UserLoginToken

@Target({ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface UserLoginToken {
    boolean required() default true;
}

3、 定义一个Entity

@Data
public class User {
    String Id;
    String username;
    String password;
}

4 、Token的生成方法

@Configuration
@ComponentScan(basePackages="com.xxx.xxx")
public class TokenCreate {
    public String getToken(User user) {
        String token="";
        token= JWT.create().withAudience(user.getUserPhone())
                .sign(Algorithm.HMAC256(user.getPassword()));
        return token;
    }
}

5 、获取请求头Token并验证Token

public class AuthenticationInterceptor implements HandlerInterceptor {
    @Autowired
    UserService userService;
    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object object) throws Exception {
        String token = httpServletRequest.getHeader("token");// 从 http 请求头中取出 token
        // 如果不是映射到方法直接通过
        if(!(object instanceof HandlerMethod)){
            return true;
        }
        HandlerMethod handlerMethod=(HandlerMethod)object;
        Method method=handlerMethod.getMethod();
        //检查是否有passtoken注释，有则跳过认证
        if (method.isAnnotationPresent(PassToken.class)) {
            PassToken passToken = method.getAnnotation(PassToken.class);
            if (passToken.required()) {
                return true;
            }
        }
        //检查有没有需要用户权限的注解
        if (method.isAnnotationPresent(UserLoginToken.class)) {
            UserLoginToken userLoginToken = method.getAnnotation(UserLoginToken.class);
            if (userLoginToken.required()) {
                // 执行认证
                if (token == null) {
                    throw new RuntimeException("无token，请重新登录");
                }
                // 获取 token 中的 user id
                String userId;
                try {
                    userId = JWT.decode(token).getAudience().get(0);
                } catch (JWTDecodeException j) {
                    throw new RuntimeException("401");
                }
                User user = userService.findUserById(userId);
                if (user == null) {
                    throw new RuntimeException("账号不存在，请重新登录");
                }
                // 验证 token
                JWTVerifier jwtVerifier = JWT.require(Algorithm.HMAC256(user.getPassword())).build();
                try {
                    jwtVerifier.verify(token);
                } catch (JWTVerificationException e) {
                    throw new RuntimeException("401");
                }
                return true;
            }
        }
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest httpServletRequest, 
                                  HttpServletResponse httpServletResponse, 
                            Object o, ModelAndView modelAndView) throws Exception {

    }
    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest, 
                                          HttpServletResponse httpServletResponse, 
                                          Object o, Exception e) throws Exception {
    }

5.1 配置

@Configuration
public class InterceptorConfig implements WebMvcConfigurer {
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(authenticationInterceptor())
                .addPathPatterns("/**");   
    }
    @Bean
    public AuthenticationInterceptor authenticationInterceptor() {
        return new AuthenticationInterceptor();
    }
}

6 、登录接口

@RestController
@RequestMapping("api")
public class UserApi {
    @Autowired
    UserService userService;
    @Autowired
    TokenService tokenCreate;
    //登录 
    @PassToken  //免token验证注解
    @PostMapping("/login")
    public Object login(@RequestBody User user){
        JSONObject jsonObject=new JSONObject();
        User userForBase=userService.findByUsername(user);
        if(userForBase==null){
            jsonObject.put("message","登录失败,账号不存在");
            return jsonObject;
        }else {
            if (!userForBase.getPassword().equals(user.getPassword())){
                jsonObject.put("message","登录失败,账号信息错误！");
                return jsonObject;
            }else {
            	//登录成功 创建token并返回
                jsonObject.put("token", tokenCreate.getToken(userForBase));
                jsonObject.put("user", userForBase);
                return jsonObject;
            }
        }
    }
    @UserLoginToken // 拦截获取header的token进行检验
    @GetMapping("/getMessage")
    public String getMessage(){
        return "棒！已通过验证！";
    }
}

OK 收工