1-2 分布式session（一）

用户登录成功以后服务器会为每一个用户生成一个token，然后将这个token返回给浏览器；同时为了实现分布式还需要将token存入redis缓存中，这样每个服务器都可以通过redis缓存来实现用户身份认证。用户在访问页面时请求中会携带这个token，服务器利用其进行身份验证。相应代码如下：

package com.miaosha.service;
import com.miaosha.dao.MiaosahaUserDao;
import com.miaosha.exception.GlobalException;
import com.miaosha.pojo.MiaoshaUser;
import com.miaosha.redis.MiaoshaUserKey;
import com.miaosha.redis.RedisService;
import com.miaosha.result.CodeMsg;
import com.miaosha.util.MD5Util;
import com.miaosha.util.UUIDUtil;
import com.miaosha.vo.LoginVo;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletResponse;

@Service
public class MiaoshaUserService {

    public static final String COOKI_NAME_TOKEN = "token";

    @Autowired
    MiaosahaUserDao miaosahaUserDao;

    @Autowired
    RedisService redisService;

    public MiaoshaUser getById(long id){
        return miaosahaUserDao.getById(id);
    }

    public boolean login(HttpServletResponse response, LoginVo loginVo){
        if(loginVo == null) {
            throw new GlobalException(CodeMsg.SERVER_ERROR);
        }
        String mobile = loginVo.getMobile();
        String formPass = loginVo.getPassword();

        //判断手机号是否存在
        MiaoshaUser user = getById(Long.parseLong(mobile));
        if(user == null) {
            throw new GlobalException(CodeMsg.MOBILE_NOT_EXIST);
        }

        //验证密码
        String dbPass = user.getPassword();
        String saltDB = user.getSalt();
        String calcPass = MD5Util.formPassToDBPass(formPass, saltDB);
        if(!calcPass.equals(dbPass)) {
            throw new GlobalException(CodeMsg.PASSWORD_ERROR);
        }

        // Token生成
        String token = UUIDUtil.uuid();
        redisService.set(MiaoshaUserKey.token, token, user);
        Cookie cookie = new Cookie(COOKI_NAME_TOKEN, token);
        cookie.setMaxAge(MiaoshaUserKey.token.expireSeconds());
        cookie.setPath("/");
        response.addCookie(cookie);
        return true;
    }

    public MiaoshaUser getByToken(String token) {
        if (StringUtils.isEmpty(token)){
            return null;
        }
        return redisService.get(MiaoshaUserKey.token, token, MiaoshaUser.class);
    }
}

controller代码：

package com.miaosha.controller;
import com.miaosha.pojo.MiaoshaUser;
import com.miaosha.redis.MiaoshaUserKey;
import com.miaosha.redis.RedisService;
import com.miaosha.service.MiaoshaUserService;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.CookieValue;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;

@Controller
@RequestMapping("/goods")
public class GoodsController {

    @Autowired
    MiaoshaUserService userService;

    @Autowired
    RedisService redisService;

    @RequestMapping("/to_list")
    public String toLogin(Model model, @CookieValue(value = MiaoshaUserService.COOKI_NAME_TOKEN, required = false) String cookieToken,
                          @RequestParam(value = MiaoshaUserService.COOKI_NAME_TOKEN, required = false) String paramToken) {
        if (StringUtils.isEmpty(cookieToken) && StringUtils.isEmpty(paramToken)){
            return "login";
        }
        String token = StringUtils.isEmpty(paramToken) ? cookieToken : paramToken;
        MiaoshaUser user = userService.getByToken(token);
        model.addAttribute("user", user);
        return "goods_list";
    }
}