基于JWT的用户token验证

1. 基于session的用户验证

2. 基于token的用户身份验证

3. jwt

jwt代码实现方式

1. 导包

<dependency>
  <groupId>com.auth0</groupId>
  <artifactId>java-jwt</artifactId>
  <version>3.18.2</version>
</dependency>

2. 在登录用户接口返回token（当用户登录时返回token）

登录接口

@PostMapping("/user-tokens")
public JsonResponse<String> login(@RequestBody User user) throws Exception {
    String token = userService.login(user);
    return new JsonResponse<>(token);
}

public String login(User user) throws Exception {
        // 判断用户登录逻辑
        ...
        //如果用户登录成功，返回token,token基于用户id
        String token = TokenUtil.generateToken(user.getId());
        return token;
    }

public class TokenUtil {

    private static final String ISSUER = "签发者";

    // 创建token
    public static String generateToken(Long userId) throws Exception {
        Algorithm algorithm = Algorithm.RSA256(RSAUtil.getPublicKey(),RSAUtil.getPrivateKey());
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(new Date());
        calendar.add(Calendar.SECOND,30);
        return JWT.create().withKeyId(String.valueOf(userId))
                .withIssuer(ISSUER)
                .withExpiresAt(calendar.getTime())
                .sign(algorithm);
    }
  
}

上面的代码会通过用户id生成一个token,前端可以得到token，然后将token报错在浏览器内存里

然后前端只要发送请求，都会带着token

服务端通过token获取用户信息

@GetMapping()
public User getUserInfo(){
    Long userId = userSupport.getCurrentUserId();
    User user = userService.getUserInfo(userId);
    return user;
}

先通过传过来的heander，得到token

public Long getCurrentUserId(){
    ServletRequestAttributes requestAttributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
    String token = requestAttributes.getRequest().getHeader("token");
    Long userId = TokenUtil.verifyToken(token);
    if(userId < 0){
        throw new ConditionException("非法用户");
    }
    return userId;
}

然后验证token，获得用户id

public class TokenUtil {

    private static final String ISSUER = "签发者";

   
    // 验证token
    public static Long verifyToken(String token){
        try {
            Algorithm algorithm = Algorithm.RSA256(RSAUtil.getPublicKey(), RSAUtil.getPrivateKey());
            JWTVerifier verifier = JWT.require(algorithm).build();
            DecodedJWT jwt = verifier.verify(token);
            String userId = jwt.getKeyId();
            return Long.valueOf(userId);
        }catch (TokenExpiredException e){
            throw new ConditionException("555","token过期!");
        }catch (Exception e){
            throw new ConditionException("非法token");
        }
    }
}

最后通过用户id获得用户信息