转载：https://blog.csdn.net/xjj1040249553/article/details/82658889
一、pom.xml配置
-
<dependency>
-
<groupId>org.springframework.boot
</groupId>
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<artifactId>spring-boot-starter-data-redis
</artifactId>
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</dependency>
-
-
<dependency>
-
<groupId>org.springframework.session
</groupId>
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<artifactId>spring-session-data-redis
</artifactId>
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</dependency>
二、application.properties的redis配置
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#redis
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spring.redis.host=
127.0.
0.1
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spring.redis.port=
6379
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spring.redis.password=
123456
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spring.redis.pool.max-idle=
8
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spring.redis.pool.min-idle=
0
-
spring.redis.pool.max-active=
8
-
spring.redis.pool.max-wait=-
1
-
#超时一定要大于0
-
spring.redis.timeout=
3000
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spring.session.store-type=redis
在配置redis时需要确保redis安装正确，并且配置notify-keyspace-events Egx，spring.redis.timeout设置为大于0，我当时这里配置为0时springboot时启不起来。
三、编写登录状态拦截器RedisSessionInterceptor
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//拦截登录失效的请求
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public
class RedisSessionInterceptor implements HandlerInterceptor
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{
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@Autowired
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private StringRedisTemplate redisTemplate;
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@Override
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public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception
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{
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//无论访问的地址是不是正确的，都进行登录验证，登录成功后的访问再进行分发，404的访问自然会进入到错误控制器中
-
HttpSession session = request.getSession();
-
if (session.getAttribute(
"loginUserId") !=
null)
-
{
-
try
-
{
-
//验证当前请求的session是否是已登录的session
-
String loginSessionId = redisTemplate.opsForValue().get(
"loginUser:" + (
long) session.getAttribute(
"loginUserId"));
-
if (loginSessionId !=
null && loginSessionId.equals(session.getId()))
-
{
-
return
true;
-
}
-
}
-
catch (Exception e)
-
{
-
e.printStackTrace();
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}
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}
-
-
response401(response);
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return
false;
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}
-
-
private void response401(HttpServletResponse response)
-
{
-
response.setCharacterEncoding(
"UTF-8");
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response.setContentType(
"application/json; charset=utf-8");
-
-
try
-
{
-
response.getWriter().print(JSON.toJSONString(
new ReturnData(StatusCode.NEED_LOGIN,
"",
"用户未登录！")));
-
}
-
catch (IOException e)
-
{
-
e.printStackTrace();
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}
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}
-
-
@Override
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public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception
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{
-
-
}
-
-
@Override
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public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception
-
{
-
-
}
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}
四、配置拦截器
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@Configuration
-
public
class WebSecurityConfig extends WebMvcConfigurerAdapter
-
{
-
@Bean
-
public RedisSessionInterceptor getSessionInterceptor()
-
{
-
return
new RedisSessionInterceptor();
-
}
-
-
@Override
-
public void addInterceptors(InterceptorRegistry registry)
-
{
-
//所有已api开头的访问都要进入RedisSessionInterceptor拦截器进行登录验证，并排除login接口(全路径)。必须写成链式，分别设置的话会创建多个拦截器。
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//必须写成getSessionInterceptor()，否则SessionInterceptor中的@Autowired会无效
-
registry.addInterceptor(getSessionInterceptor()).addPathPatterns(
"/api/**").excludePathPatterns(
"/api/user/login");
-
super.addInterceptors(registry);
-
}
-
}
五、登录控制器
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@RestController
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@RequestMapping(value = "/api/user")
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public
class LoginController
-
{
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@Autowired
-
private UserService userService;
-
-
@Autowired
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private StringRedisTemplate redisTemplate;
-
-
@RequestMapping("/login")
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public ReturnData login(HttpServletRequest request, String account, String password)
-
{
-
User user = userService.findUserByAccountAndPassword(account, password);
-
if (user !=
null)
-
{
-
HttpSession session = request.getSession();
-
session.setAttribute(
"loginUserId", user.getUserId());
-
redisTemplate.opsForValue().
set(
"loginUser:" + user.getUserId(), session.getId());
-
-
return new ReturnData(StatusCode.REQUEST_SUCCESS, user,
"登录成功！");
-
}
-
else
-
{
-
throw new MyException(StatusCode.ACCOUNT_OR_PASSWORD_ERROR,
"账户名或密码错误！");
-
}
-
}
-
-
@RequestMapping(value = "/getUserInfo")
-
public ReturnData
get(long userId)
-
{
-
User user = userService.findUserByUserId(userId);
-
if (user !=
null)
-
{
-
return new ReturnData(StatusCode.REQUEST_SUCCESS, user,
"查询成功！");
-
}
-
else
-
{
-
throw new MyException(StatusCode.USER_NOT_EXIST,
"用户不存在！");
-
}
-
}
-
}
六、效果
我在浏览器上登录，然后获取用户信息，再在postman上登录相同的账号，浏览器再获取用户信息，就会提示401错误了，浏览器需要重新登录才能获取得到用户信息，同样，postman上登录的账号就失效了。
浏览器：
postman：
七、核心原理详解
分布式session需要解决两个难点：1、正确配置redis让springboot把session托管到redis服务器。2、唯一登录。
1、redis：
redis需要能正确启动到出现如下效果才证明redis正常配置并启动
同时还要保证配置正确
-
@EnableCaching
-
@EnableRedisHttpSession(maxInactiveIntervalInSeconds =
30)
//session过期时间(秒)
-
@Configuration
-
public class RedisSessionConfig
-
{
-
@Bean
-
public static ConfigureRedisAction configureRedisAction()
-
{
-
//让springSession不再执行config命令
-
return
ConfigureRedisAction
.NO_OP;
-
}
-
}
springboot启动后能在redis上查到缓存的session才能说明整个redis+springboot配置成功！
2、唯一登录：
1、用户登录时，在redis中记录该userId对应的sessionId，并将userId保存到session中。
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HttpSession session = request.getSession();
-
session.setAttribute("loginUserId", user.getUserId());
-
redisTemplate.opsForValue().set("loginUser:" + user.getUserId(), session.getId());
2、访问接口时，会在RedisSessionInterceptor拦截器中的preHandle()中捕获，然后根据该请求发起者的session中保存的userId去redis查当前已登录的sessionId，若查到的sessionId与访问者的sessionId相等，那么说明请求合法，放行。否则抛出401异常给全局异常捕获器去返回给客户端401状态。
唯一登录经过我的验证后满足需求，暂时没有出现问题，也希望大家能看看有没有问题，有的话给我点好的建议！