java后端图片验证码实现

图片验证码

引入hutook工具依赖

xml 复制代码

    <dependencies>
        <dependency>
            <groupId>cn.hutool</groupId>
            <artifactId>hutool-all</artifactId>
            <version>5.5.2</version>
        </dependency>
    </dependencies>

VO实体类

java 复制代码

@Data
@Schema(description = "验证码响应结果实体类")
public class ValidateCodeVo {

    @Schema(description = "验证码key")
    private String codeKey ;        // 验证码的key

    @Schema(description = "验证码value")
    private String codeValue ;      // 图片验证码对应的字符串数据

}

底层实现

在Service层使用hutool生成图片验证码，并在controller层调用进行了

java 复制代码

@Service
public class ValidateCodeServiceImpl implements ValidateCodeService {

    @Autowired
    private RedisTemplate<String,String> redisTemplate;

    //生成图片验证码
    @Override
    public ValidateCodeVo generateValidateCode() {
        //1 通过工具 hutool 生成图片验证码
        //150：宽度，48：高度，4：验证码值数量，2：验证码划痕数量，干扰程度
        CircleCaptcha circleCaptcha = CaptchaUtil.createCircleCaptcha(150, 48, 4, 2);
        String codeValue = circleCaptcha.getCode();//4位验证码值
        String imageBase64 = circleCaptcha.getImageBase64();//返回图片验证码，对图片进行了base64编码
        //2 把验证码存储到redis里，设置redis的key：uuid   redis的value：验证码值
        //设置过期时间
        String key = UUID.randomUUID().toString().replaceAll("-", "");
        redisTemplate.opsForValue().set("user:validate"+key,codeValue,
                                        5, TimeUnit.MINUTES);//过期时间5，单位分钟
        //返回ValidateCodeVo对象
        ValidateCodeVo validateCodeVo = new ValidateCodeVo();
        validateCodeVo.setCodeKey(key);//redis中存储数据的key
        validateCodeVo.setCodeValue("data:image/png;base64," + imageBase64);//是要把图片设置进去，格式固定，这个数据会在页面上直接通过图片的形式显示出来
        return validateCodeVo;
    }
}

DTO实体类

java 复制代码

@Data
@Schema(description = "用户登录请求参数")
public class LoginDto {

    @Schema(description = "用户名")
    private String userName ;

    @Schema(description = "密码")
    private String password ;

    @Schema(description = "提交验证码")
    private String captcha ;

    @Schema(description = "验证码key")
    private String codeKey ;

}

验证码校验

验证码校验应该在用户登录的接口实现，和用户名密码的代码放一块

java 复制代码

@Service
public class SysUserServiceImpl implements SysUserService {

    @Autowired
    private SysUserMapper sysUserMapper ;
    @Autowired
    private RedisTemplate<String,String> redisTemplate;

    @Override
    public LoginVo login(LoginDto loginDto) {
        //1 获取输入的验证码和存储到redis的key名称
        String captcha = loginDto.getCaptcha();
        String key = loginDto.getCodeKey();
        //2 根据获取到的redis里面的key，查询redis里面存储的验证码
        String redisCode = redisTemplate.opsForValue().get("user:validate" + key);
        //3 比较输入的验证码和redis存储的验证码是否一致
        if(StrUtil.isEmpty(captcha) || !StrUtil.equalsIgnoreCase(redisCode,captcha)){
            //4 如果不一致，提示用户校验失败
            throw new GuiguException(ResultCodeEnum.VALIDATECODE_ERROR);
        }
        //5 如果一致，删除redis里面的验证码
        redisTemplate.delete("user:validate" + key);

        QueryWrapper<SysUser> queryWrapper = new QueryWrapper<>();
        queryWrapper.eq("username",loginDto.getUserName());
        SysUser sysUser = sysUserMapper.selectOne(queryWrapper);
        if(sysUser==null){
//            throw new RuntimeException("用户名不存在！");
            throw new GuiguException(ResultCodeEnum.LOGIN_ERROR);
        }
        String input_password = DigestUtils.md5DigestAsHex(loginDto.getPassword().getBytes());
        if(!sysUser.getPassword().equals(input_password)){
//            throw new RuntimeException("密码不正确！");
            throw new GuiguException(ResultCodeEnum.LOGIN_ERROR);
        }
        String token = UUID.randomUUID().toString().replaceAll("-", "");
        redisTemplate.opsForValue().set("user:login"+token, JSON.toJSONString(sysUser),7, TimeUnit.DAYS);
        LoginVo loginVo = new LoginVo();
        loginVo.setToken(token);
        return loginVo;
    }
}