vue+springboot realizes login verification code

<dependency>
     <groupId>com.github.penggle</groupId>
     <artifactId>kaptcha</artifactId>
     <version>2.3.2</version>
</dependency>

package com.brilliance.module.system.controller.util;
 
import com.google.code.kaptcha.impl.DefaultKaptcha;
import com.google.code.kaptcha.util.Config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
 
import java.util.Properties;
 
@Configuration
public class KaptchaConfig {
    @Bean
    public DefaultKaptcha getDefaultKaptcha() {
        DefaultKaptcha defaultKaptcha = new DefaultKaptcha();
        Properties properties = new Properties();
        // Image width properties.setProperty("kaptcha.image.width", "180");
        // Image height properties.setProperty("kaptcha.image.height", "50");
        // Picture border properties.setProperty("kaptcha.border", "yes");
        // Border color properties.setProperty("kaptcha.border.color", "105,179,90");
        // Font color properties.setProperty("kaptcha.textproducer.font.color", "blue");
        // font size properties.setProperty("kaptcha.textproducer.font.size", "40");
        //session key
        properties.setProperty("kaptcha.session.key", "code");
        // Verification code length properties.setProperty("kaptcha.textproducer.char.length", "4");
        // font properties.setProperty("kaptcha.textproducer.font.names", "Songti, Kaiti, Microsoft YaHei");
        Config config = new Config(properties);
        defaultKaptcha.setConfig(config);
        return defaultKaptcha;
    }
}

@RestController
@RequestMapping("/api/user")
@Api(tags = "System User Management")
public class SysUserController extends AbstractController {
 @Autowired
 private SysUserService sysUserService;
 @Autowired
 private DefaultKaptcha defaultKaptcha;
 
 @Autowired
 RedisTemplate redisTemplate;
 
 @GetMapping("/createImageCode")
 public void createImageCode(HttpServletRequest request, HttpServletResponse response) throws IOException {
  response.setHeader("Cache-Control", "no-store, no-cache");
  response.setContentType("image/jpeg");
  // Generate text verification code String text = defaultKaptcha.createText();
  // Generate image verification code BufferedImage image = defaultKaptcha.createImage(text);
  // Here we use redis to cache the value of the verification code and set the expiration time to 60 seconds redisTemplate.opsForValue().set("imageCode",text,60, TimeUnit.SECONDS);
  ServletOutputStream out = response.getOutputStream();
  ImageIO.write(image, "jpg", out);
  out.flush();
  out.close();
 }

@PostMapping("/compareCode")
public RESULT compareCode(@RequestBody String verificationCode) {
    if(!redisTemplate.hasKey("imageCode")) {
  return RESULT.error(500,"Verification code has expired");
 }
 String code = redisTemplate.opsForValue().get("imageCode").toString();
 if(StringUtils.equals(verificationCode,code)) {
  return RESULT.ok();
 } else {
  return RESULT.error(500,"Incorrect verification code input");
 }
}