SpringBoot集成JWT（极简版）

在WebConfig配置类中设置接口统一前缀

import org.springframework.context.annotation.Configuration;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.servlet.config.annotation.PathMatchConfigurer;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
public class WebConfig implements  WebMvcConfigurer {
    @Override
    public void configurePathMatch(PathMatchConfigurer configurer) {
        // 指定controller统一的接口前缀
        configurer.addPathPrefix("/api", clazz -> clazz.isAnnotationPresent(RestController.class));
    }
}

导入JWT依赖

<dependency>
    <groupId>com.auth0</groupId>
    <artifactId>java-jwt</artifactId>
    <version>3.10.3</version>
</dependency>

JWT工具类TokenUtils.java(生成token的工具类)

import cn.hutool.core.date.DateUtil;
import cn.hutool.core.util.StrUtil;
import com.auth0.jwt.JWT;
import com.auth0.jwt.algorithms.Algorithm;
import com.bai.entity.Admin;
import com.bai.service.AdminService;

import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import java.util.Date;

@Component
@Slf4j
public class TokenUtils {

    private static AdminService staticAdminService;

    @Resource
    private AdminService adminService;

    @PostConstruct
    public void setUserService() {
        staticAdminService = adminService;
    }

    /**
     * 生成token
     *
     * @return
     */
    public static String genToken(String adminId, String sign) {
        return JWT.create().withAudience(adminId) // 将 user id 保存到 token 里面,作为载荷
                .withExpiresAt(DateUtil.offsetHour(new Date(), 2)) // 2小时后token过期
                .sign(Algorithm.HMAC256(sign)); // 以 password 作为 token 的密钥
    }

    /**
     * 获取当前登录的用户信息
     *
     * @return user对象
     *  /admin?token=xxxx
     */
    public static Admin getCurrentAdmin() {
        String token = null;
        try {
            HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
            token = request.getHeader("token");
            if (StrUtil.isNotBlank(token)) {
                token = request.getParameter("token");
            }
            if (StrUtil.isBlank(token)) {
                log.error("获取当前登录的token失败， token: {}", token);
                return null;
            }
            String adminId = JWT.decode(token).getAudience().get(0);
            return staticAdminService.getById(Integer.valueOf(adminId));
        } catch (Exception e) {
            log.error("获取当前登录的管理员信息失败, token={}", token,  e);
            return null;
        }
    }
}

拦截器JwtInterceptor.java

import cn.hutool.core.util.StrUtil;
import com.auth0.jwt.JWT;
import com.auth0.jwt.JWTVerifier;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.exceptions.JWTVerificationException;
import com.bai.entity.Admin;
import com.bai.exception.ServiceException;
import com.bai.service.AdminService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

@Component
@Slf4j
public class LoginJWTInterceptor implements HandlerInterceptor {

    private static final String ERROR_CODE_401 = "401";

    @Autowired
    private AdminService adminService;

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) {

        //这里是判断浏览器请求头里的token
        String token = request.getHeader("token");

        if (StrUtil.isBlank(token)) {
            token = request.getParameter("token");
        }

        // 执行认证
        if (StrUtil.isBlank(token)) {
            throw new ServiceException(ERROR_CODE_401, "无token，请重新登录");
        }
        // 获取 token 中的adminId
        String adminId;
        Admin admin;
        try {
            adminId = JWT.decode(token).getAudience().get(0);
            // 根据token中的userid查询数据库
            admin = adminService.getById(Integer.parseInt(adminId));
        } catch (Exception e) {
            String errMsg = "token验证失败，请重新登录";
            log.error(errMsg + ", token=" + token, e);
            throw new ServiceException(ERROR_CODE_401, errMsg);
        }
        if (admin == null) {
            throw new ServiceException(ERROR_CODE_401, "用户不存在，请重新登录");
        }

        try {
            // 用户密码加签验证 token
            JWTVerifier jwtVerifier = JWT.require(Algorithm.HMAC256(admin.getPassword())).build();
            jwtVerifier.verify(token); // 验证token
        } catch (JWTVerificationException e) {
            throw new ServiceException(ERROR_CODE_401, "token验证失败，请重新登录");
        }
        return true;
    }
}

在WebConfig配置类中添加自定义拦截器

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.servlet.config.annotation.CorsRegistry;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.PathMatchConfigurer;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
@Configuration
public class WebConfig implements WebMvcConfigurer {

    @Autowired
    private LoginJWTInterceptor loginJWTInterceptor;

    @Override
    public void configurePathMatch(PathMatchConfigurer configurer) {
        // 指定controller统一的接口前缀
        configurer.addPathPrefix("/api", clazz -> clazz.isAnnotationPresent(RestController.class));
    }

    // 加自定义拦截器JwtInterceptor，设置拦截规则
    //.excludePathPatterns("/api/admin/login");放开登录接口，因为登录的时候还没有token
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(loginJWTInterceptor)  // 添加所有路径需要校验
                .addPathPatterns("/api/**").excludePathPatterns("/api/admin/login", "/api/admin/register");//不需要拦截的接口
    }

}

设置自定义头配置（前端在request拦截器设置自定义头）

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.cors.CorsConfiguration;
import org.springframework.web.cors.UrlBasedCorsConfigurationSource;
import org.springframework.web.filter.CorsFilter;


@Configuration
public class CrosConfiguration {

    @Bean
    public CorsFilter corsFilter() {
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        CorsConfiguration corsConfiguration = new CorsConfiguration();
        corsConfiguration.addAllowedOrigin("*"); // 1 设置访问源地址
        corsConfiguration.addAllowedHeader("*"); // 2 设置访问源请求头
        corsConfiguration.addAllowedMethod("*"); // 3 设置访问源请求方法
        source.registerCorsConfiguration("/**", corsConfiguration); // 4 对接口配置跨域设置
        return new CorsFilter(source);
    }
}