前言

最近发现一个有趣的 Java 验证码库，能够生成各种行为验证码：滑块、旋转、点选验证码。

github: https://github.com/tianaiyouqing/tianai-captcha

pom 依赖：

<!-- springboot -->
<dependency>
    <groupId>cloud.tianai.captcha</groupId>
    <artifactId>tianai-captcha-springboot-starter</artifactId>
    <version>1.3.3</version>
</dependency>

<!-- 非springboot -->
<dependency>
    <groupId>cloud.tianai.captcha</groupId>
    <artifactId>tianai-captcha</artifactId>
    <version>1.3.3</version>
</dependency>

注：以下代码大部分来自官方demo: https://gitee.com/tianai/tianai-captcha-demo

一、后端springboot

1.1 yml 配置

captcha:
  # 如果项目中使用到了redis，滑块验证码会自动把验证码数据存到redis中， 这里配置redis的key的前缀,默认是captcha:slider
  prefix: captcha
  # 验证码过期时间，默认是2分钟,单位毫秒， 可以根据自身业务进行调整
  expire:
    # 默认缓存时间 2分钟
    default: 10000
    # 针对 点选验证码 过期时间设置为 2分钟， 因为点选验证码验证比较慢，把过期时间调整大一些
    WORD_IMAGE_CLICK: 20000
  # 使用加载系统自带的资源， 默认是 false
  init-default-resource: false
  cache:
    # 缓存控制， 默认为false不开启
    enabled: true
    # 验证码会提前缓存一些生成好的验证数据， 默认是20
    cacheSize: 20
    # 缓存拉取失败后等待时间 默认是 5秒钟
    wait-time: 5000
    # 缓存检查间隔 默认是2秒钟
    period: 2000
    secondary:
      # 二次验证， 默认false 不开启
      enabled: false
      # 二次验证过期时间， 默认 2分钟
      expire: 120000
      # 二次验证缓存key前缀，默认是 captcha:secondary
      keyPrefix: "captcha:secondary"

1.2 跨域配置

跨域问题

@Configuration
public class CorsConfig {
    @Bean
    public WebMvcConfigurer corsConfigurer() {
        return new WebMvcConfigurer() {
            // 重写父类提供的跨域请求处理的接口
            @Override
            public void addCorsMappings(CorsRegistry registry) {
                // 添加映射路径
                registry.addMapping("/**")
                        .allowedOrigins("*")                         // 放行哪些域名，可以多个
                        .allowCredentials(true)                             // 是否发送Cookie信息
                        .allowedMethods("GET", "HEAD", "POST", "PUT", "DELETE", "OPTIONS", "PATCH") // 放行哪些请求方式
                        .allowedHeaders("*")                                // 放行哪些原始域(头部信息)
                        .exposedHeaders("Header1", "Header2")               // 暴露哪些头部信息（因为跨域访问默认不能获取全部头部信息）
                        .maxAge(3600);                                      // 预请求的结果有效期，默认1800分钟,3600是一小时
            }
        };
    }
}

1.3 资源配置

@Component
public class MyResourceStore extends DefaultResourceStore {

    public MyResourceStore() {

        // 滑块验证码 模板 (系统内置)
        Map<String, Resource> template1 = new HashMap<>(4);
        template1.put(SliderCaptchaConstant.TEMPLATE_ACTIVE_IMAGE_NAME, new Resource(ClassPathResourceProvider.NAME, DEFAULT_SLIDER_IMAGE_TEMPLATE_PATH.concat("/1/active.png")));
        template1.put(SliderCaptchaConstant.TEMPLATE_FIXED_IMAGE_NAME, new Resource(ClassPathResourceProvider.NAME, DEFAULT_SLIDER_IMAGE_TEMPLATE_PATH.concat("/1/fixed.png")));
        template1.put(SliderCaptchaConstant.TEMPLATE_MATRIX_IMAGE_NAME, new Resource(ClassPathResourceProvider.NAME, DEFAULT_SLIDER_IMAGE_TEMPLATE_PATH.concat("/1/matrix.png")));
        Map<String, Resource> template2 = new HashMap<>(4);
        template2.put(SliderCaptchaConstant.TEMPLATE_ACTIVE_IMAGE_NAME, new Resource(ClassPathResourceProvider.NAME, DEFAULT_SLIDER_IMAGE_TEMPLATE_PATH.concat("/2/active.png")));
        template2.put(SliderCaptchaConstant.TEMPLATE_FIXED_IMAGE_NAME, new Resource(ClassPathResourceProvider.NAME, DEFAULT_SLIDER_IMAGE_TEMPLATE_PATH.concat("/2/fixed.png")));
        template2.put(SliderCaptchaConstant.TEMPLATE_MATRIX_IMAGE_NAME, new Resource(ClassPathResourceProvider.NAME, DEFAULT_SLIDER_IMAGE_TEMPLATE_PATH.concat("/2/matrix.png")));
        // 旋转验证码 模板 (系统内置)
        Map<String, Resource> template3 = new HashMap<>(4);
        template3.put(SliderCaptchaConstant.TEMPLATE_ACTIVE_IMAGE_NAME, new Resource(ClassPathResourceProvider.NAME, StandardSliderImageCaptchaGenerator.DEFAULT_SLIDER_IMAGE_TEMPLATE_PATH.concat("/3/active.png")));
        template3.put(SliderCaptchaConstant.TEMPLATE_FIXED_IMAGE_NAME, new Resource(ClassPathResourceProvider.NAME, StandardSliderImageCaptchaGenerator.DEFAULT_SLIDER_IMAGE_TEMPLATE_PATH.concat("/3/fixed.png")));
        template3.put(SliderCaptchaConstant.TEMPLATE_MATRIX_IMAGE_NAME, new Resource(ClassPathResourceProvider.NAME, StandardSliderImageCaptchaGenerator.DEFAULT_SLIDER_IMAGE_TEMPLATE_PATH.concat("/3/matrix.png")));

        // 1. 添加一些模板
        addTemplate(CaptchaTypeConstant.SLIDER, template1);
        addTemplate(CaptchaTypeConstant.SLIDER, template2);
        addTemplate(CaptchaTypeConstant.ROTATE, template3);

        // 2. 添加自定义背景图片
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/a.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/b.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/c.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/d.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/e.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/g.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/h.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/i.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/j.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/01.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/02.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/03.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/04.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/05.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/06.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/07.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/08.jpg"));
        addResource(CaptchaTypeConstant.SLIDER, new Resource("classpath", "bgimages/09.jpg"));

        addResource(CaptchaTypeConstant.ROTATE, new Resource("classpath", "bgimages/10.jpg"));
        addResource(CaptchaTypeConstant.ROTATE, new Resource("classpath", "bgimages/48.jpg"));

        addResource(CaptchaTypeConstant.CONCAT, new Resource("classpath", "bgimages/10.jpg"));
        addResource(CaptchaTypeConstant.CONCAT, new Resource("classpath", "bgimages/48.jpg"));

        addResource(CaptchaTypeConstant.WORD_IMAGE_CLICK, new Resource("classpath", "bgimages/02.jpg"));
        addResource(CaptchaTypeConstant.WORD_IMAGE_CLICK, new Resource("classpath", "bgimages/03.jpg"));
        addResource(CaptchaTypeConstant.WORD_IMAGE_CLICK, new Resource("classpath", "bgimages/06.jpg"));
        addResource(CaptchaTypeConstant.WORD_IMAGE_CLICK, new Resource("classpath", "bgimages/08.jpg"));
    }
}

1.4 Controller

@RestController
@RequestMapping("/")
public class CaptchaDemoController {

    @Autowired
    private ImageCaptchaApplication application;

    @GetMapping("/index")
    public ResponseEntity index(String type) {
            CaptchaResponse<ImageCaptchaVO> res = application.generateCaptcha(type);
            return ResponseEntity.ok(res);
    }

    @PostMapping ("/check")
    public ResponseEntity check(@RequestBody CaptchaRequest<Map> request) {
        boolean match = application.matching(request.getId(), request.getCaptchaTrack());
        return ResponseEntity.ok(match);
    }
}

二、前端jquery

2.1 通用代码

• 通用js 代码

  通用js这块代码滑动验证码通用，最主要的就是提供记录用户滑动轨迹的三个函数，分别为down,move和up

  var currentCaptchaConfig;
  /** 是否打印日志 */
  var isPrintLog = false;
  
  function clearPreventDefault(event) {
      if (event.preventDefault) {
          event.preventDefault();
      }
  }
  
  function clearAllPreventDefault($div) {
      $div.each(function (index, el) {
          el.addEventListener('touchmove', clearPreventDefault, false);
      });
  }
  
  function reductionAllPreventDefault($div) {
      $div.each(function (index, el) {
          el.removeEventListener('touchmove', clearPreventDefault);
      });
  }
  
  function printLog(...params) {
      if (isPrintLog) {
          console.log(JSON.stringify(params));
      }
  }
  
  function initConfig(bgImageWidth, bgImageHeight, sliderImageWidth, sliderImageHeight, end) {
      currentCaptchaConfig = {
          startTime: new Date(),
          trackArr: [],
          movePercent: 0,
          bgImageWidth,
          bgImageHeight,
          sliderImageWidth,
          sliderImageHeight,
          end
      }
      printLog("init", currentCaptchaConfig);
      return currentCaptchaConfig;
  }
  
  function down(event) {
      let targetTouches = event.originalEvent ? event.originalEvent.targetTouches : event.targetTouches;
      let startX = event.pageX;
      let startY = event.pageY;
      if (startX === undefined) {
          startX = Math.round(targetTouches[0].pageX);
          startY = Math.round(targetTouches[0].pageY);
      }
      currentCaptchaConfig.startX = startX;
      currentCaptchaConfig.startY = startY;
  
      const pageX = currentCaptchaConfig.startX;
      const pageY = currentCaptchaConfig.startY;
      const startTime = currentCaptchaConfig.startTime;
      const trackArr = currentCaptchaConfig.trackArr;
      trackArr.push({
          x: pageX - startX,
          y: pageY - startY,
          type: "down",
          t: (new Date().getTime() - startTime.getTime())
      });
      printLog("start", startX, startY)
      // pc
      window.addEventListener("mousemove", move);
      window.addEventListener("mouseup", up);
      // 手机端
      window.addEventListener("touchmove", move, false);
      window.addEventListener("touchend", up, false);
      doDown(currentCaptchaConfig);
  }
  
  function move(event) {
      if (event instanceof TouchEvent) {
          event = event.touches[0];
      }
      let pageX = Math.round(event.pageX);
      let pageY = Math.round(event.pageY);
      const startX = currentCaptchaConfig.startX;
      const startY = currentCaptchaConfig.startY;
      const startTime = currentCaptchaConfig.startTime;
      const end = currentCaptchaConfig.end;
      const bgImageWidth = currentCaptchaConfig.bgImageWidth;
      const trackArr = currentCaptchaConfig.trackArr;
      let moveX = pageX - startX;
      const track = {
          x: pageX - startX,
          y: pageY - startY,
          type: "move",
          t: (new Date().getTime() - startTime.getTime())
      };
      trackArr.push(track);
      if (moveX < 0) {
          moveX = 0;
      } else if (moveX > end) {
          moveX = end;
      }
      currentCaptchaConfig.moveX = moveX;
      currentCaptchaConfig.movePercent = moveX / bgImageWidth;
      doMove(currentCaptchaConfig);
      printLog("move", track)
  }
  
  function up(event) {
      window.removeEventListener("mousemove", move);
      window.removeEventListener("mouseup", up);
      window.removeEventListener("touchmove", move);
      window.removeEventListener("touchend", up);
      if (event instanceof TouchEvent) {
          event = event.changedTouches[0];
      }
      currentCaptchaConfig.stopTime = new Date();
      let pageX = Math.round(event.pageX);
      let pageY = Math.round(event.pageY);
      const startX = currentCaptchaConfig.startX;
      const startY = currentCaptchaConfig.startY;
      const startTime = currentCaptchaConfig.startTime;
      const trackArr = currentCaptchaConfig.trackArr;
  
      const track = {
          x: pageX - startX,
          y: pageY - startY,
          type: "up",
          t: (new Date().getTime() - startTime.getTime())
      }
  
      trackArr.push(track);
      printLog("up", track)
      valid(currentCaptchaConfig);
  }
  

• 通用css 样式

  common.css 通用样式

  .slider {
      background-color: #fff;
      width: 278px;
      height: 285px;
      z-index: 999;
      box-sizing: border-box;
      padding: 9px;
      border-radius: 6px;
      box-shadow: 0 0 11px 0 #999999;
  }
  
  .slider .content {
      width: 100%;
      height: 159px;
      position: relative;
  }
  
  .bg-img-div {
      width: 100%;
      height: 100%;
      position: absolute;
      transform: translate(0px, 0px);
  }
  
  .slider-img-div {
      height: 100%;
      position: absolute;
      transform: translate(0px, 0px);
  }
  
  .bg-img-div img {
      width: 100%;
  }
  
  .slider-img-div img {
      height: 100%;
  }
  
  .slider .slider-move {
      height: 60px;
      width: 100%;
      margin: 11px 0;
      position: relative;
  }
  
  .slider .bottom {
      height: 19px;
      width: 100%;
  }
  
  .refresh-btn, .close-btn, .slider-move-track, .slider-move-btn {
      background: url(https://static.geetest.com/static/ant/sprite.1.2.4.png) no-repeat;
  }
  
  .refresh-btn, .close-btn {
      display: inline-block;
  }
  
  .slider-move .slider-move-track {
      line-height: 38px;
      font-size: 14px;
      text-align: center;
      white-space: nowrap;
      color: #88949d;
      -moz-user-select: none;
      -webkit-user-select: none;
      user-select: none;
  }
  
  .slider {
      user-select: none;
  }
  
  .slider-move .slider-move-btn {
      transform: translate(0px, 0px);
      background-position: -5px 11.79625%;
      position: absolute;
      top: -12px;
      left: 0;
      width: 66px;
      height: 66px;
  }
  
  .slider-move-btn:hover, .close-btn:hover, .refresh-btn:hover {
      cursor: pointer
  }
  
  .bottom .close-btn {
      width: 20px;
      height: 20px;
      background-position: 0 44.86874%;
  }
  
  .bottom .refresh-btn {
      width: 20px;
      height: 20px;
      background-position: 0 81.38425%;
  }
  

2.2 滑动验证码

• html

  <!DOCTYPE html>
  <html lang="en">
  <head>
      <meta charset="UTF-8">
      <meta http-equiv="X-UA-Compatible" content="IE=edge">
      <meta name="viewport" content="width=device-width, initial-scale=1.0">
      <title>滑动验证码</title>
      <link rel="stylesheet" type="text/css" href="common.css">
  </head>
  
  <body>
  <div class="slider">
      <div class="content">
          <div class="bg-img-div">
              <img id="bg-img" src="" alt/>
          </div>
          <div class="slider-img-div" id="slider-img-div">
              <img id="slider-img" src="" alt/>
          </div>
      </div>
      <div class="slider-move">
          <div class="slider-move-track">
              拖动滑块完成拼图
          </div>
          <div class="slider-move-btn" id="slider-move-btn"></div>
      </div>
      <div class="bottom">
          <div class="close-btn" id="slider-close-btn"></div>
          <div class="refresh-btn" id="slider-refresh-btn"></div>
      </div>
  </div>
  <script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
  <script src="index.js"></script>
  <script type="text/javascript" src="slider.js"></script>
  </body>
  </html>
  

• slider.js

  let currentCaptchaId = null;
  $(function () {
      clearAllPreventDefault($(".slider"));
      refreshCaptcha();
  })
  
  $("#slider-move-btn").mousedown(down);
  $("#slider-move-btn").on("touchstart", down);
  
  $("#slider-close-btn").click(() => {
  });
  
  $("#slider-refresh-btn").click(() => {
      refreshCaptcha();
  });
  
  function valid(captchaConfig) {
  
      let data = {
          'id' : currentCaptchaId,
          'captchaTrack': {
              bgImageWidth: captchaConfig.bgImageWidth,
              bgImageHeight: captchaConfig.bgImageHeight,
              sliderImageWidth: captchaConfig.sliderImageWidth,
              sliderImageHeight: captchaConfig.sliderImageHeight,
              startSlidingTime: captchaConfig.startTime,
              endSlidingTime: captchaConfig.stopTime,
              trackList: captchaConfig.trackArr
          }
      }
     
      $.ajax({
          type:"POST",
          url:"http://localhost:8080/check",
          contentType: "application/json", 
          dataType:"json",
          data:JSON.stringify(data),
          success:function (res) {
              if (res) {
                  alert("验证成功!!!");
              }
              refreshCaptcha();
          }
      })
  }
  
  function refreshCaptcha() {
      $.get("http://localhost:8080/index?type=SLIDER", function (data) {
          reset();
          currentCaptchaId = data.id;
          const bgImg = $("#bg-img");
          const sliderImg = $("#slider-img");
          bgImg.attr("src", data.captcha.backgroundImage);
          sliderImg.attr("src", data.captcha.sliderImage);
          initConfig(bgImg.width(), bgImg.height(), sliderImg.width(), sliderImg.height(), 206);
      })
  }
  
  function doDown() {
      $("#slider-move-btn").css("background-position", "-5px 31.0092%")
  }
  
  function doMove(currentCaptchaConfig) {
      const moveX = currentCaptchaConfig.moveX;
      $("#slider-move-btn").css("transform", "translate(" + moveX + "px, 0px)")
      $("#slider-img-div").css("transform", "translate(" + moveX + "px, 0px)")
  }
  function reset() {
      $("#slider-move-btn").css("background-position", "-5px 11.79625%")
      $("#slider-move-btn").css("transform", "translate(0px, 0px)")
      $("#slider-img-div").css("transform", "translate(0px, 0px)")
      currentCaptchaId = null;
  }
  

• 最终结果

  

2.3 旋转验证码

• html

  <!DOCTYPE html>
  <html lang="en">
  
  <head>
      <meta charset="UTF-8">
      <meta http-equiv="X-UA-Compatible" content="IE=edge">
      <meta name="viewport" content="width=device-width, initial-scale=1.0">
      <title>旋转验证码</title>
      <link rel="stylesheet" type="text/css" href="common.css">
      <style>
          .after {
              color: #88949d;
          }
  
          .rotate-img-div {
              height: 100%;
              position: absolute;
              transform: rotate(0deg);
              margin-left: 50px;
          }
  
          .rotate-img-div img {
              height: 100%;
          }
      </style>
  </head>
  
  <body>
  <div class="slider rotate">
      <div class="content">
          <div class="bg-img-div">
              <img id="rotate-bg-img" src="" alt/>
          </div>
          <div class="rotate-img-div">
              <img id="rotate-image" src="" alt/>
          </div>
      </div>
      <div class="slider-move">
          <div class="slider-move-track">
              拖动滑块旋转正确位置
          </div>
          <div class="slider-move-btn" id="rotate-move-btn"></div>
      </div>
      <div class="bottom">
          <div class="close-btn" id="rotate-close-btn"></div>
          <div class="refresh-btn" id="rotate-refresh-btn"></div>
      </div>
  </div>
  <script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
  <script src="index.js"></script>
  <script src="rotate.js"></script>
  </body>
  </html>
  

• rotate.js

  $(function () {
      refreshCaptcha();
      clearAllPreventDefault($(".slider"))
  })
  
  //  旋转
  let currentCaptchaId = null;
  function refreshCaptcha() {
      $.get("http://localhost:8080/index?type=ROTATE", function (data) {
          reset();
          currentCaptchaId = data.id;
          const bgImg = $("#rotate-bg-img");
          const sliderImg = $("#rotate-image");
          bgImg.attr("src", data.captcha.backgroundImage);
          sliderImg.attr("src", data.captcha.sliderImage);
          initConfig(206, bgImg.height(), sliderImg.width(), sliderImg.height(), 206);
      })
  }
  
  $("#rotate-move-btn").mousedown(down);
  $("#rotate-move-btn").on("touchstart", down);
  
  function doDown() {
      $("#slider-move-btn").css("background-position", "-5px 31.0092%")
  }
  
  
  function doMove(currentCaptchaConfig) {
      const moveX = currentCaptchaConfig.moveX;
      $("#rotate-move-btn").css("transform", "translate(" + moveX + "px, 0px)")
      $(".rotate-img-div").css("transform", "rotate(" + (moveX / (currentCaptchaConfig.end / 360)) + "deg)")
  }
  
  function valid(captchaConfig) {
  
      let data = {
          bgImageWidth: captchaConfig.bgImageWidth,
          bgImageHeight: captchaConfig.bgImageHeight,
          sliderImageWidth: captchaConfig.sliderImageWidth,
          sliderImageHeight: captchaConfig.sliderImageHeight,
          startSlidingTime: captchaConfig.startTime,
          endSlidingTime: captchaConfig.stopTime, // 官方demo 这里有个语法错误
          trackList: captchaConfig.trackArr
      };
      
      let sendData = {
          'id' : currentCaptchaId,
          'captchaTrack': data
      }
      $.ajax({
          type:"POST",
          url:"http://localhost:8080/check",
          contentType: "application/json", 
          dataType:"json",
          data:JSON.stringify(sendData),
          success:function (res) {
              if (res) {
                  alert("验证成功!!!");
              }
              refreshCaptcha();
          }
      })
  }
  
  $("#slider-close-btn").click(() => {
  });
  
  $("#rotate-refresh-btn").click(() => {
      refreshCaptcha();
  });
  
  function reset() {
      $("#rotate-move-btn").css("background-position", "-5px 11.79625%")
      $("#rotate-move-btn").css("transform", "translate(0px, 0px)")
      $(".rotate-img-div").css("transform", "rotate(0deg)")
      currentCaptchaId = null;
  }
  

• 最终结果

  

2.4 滑动还原验证码

• html

  <!DOCTYPE html>
  <html lang="en">
  
  <head>
      <meta charset="UTF-8">
      <meta http-equiv="X-UA-Compatible" content="IE=edge">
      <meta name="viewport" content="width=device-width, initial-scale=1.0">
      <title>滑动还原验证码</title>
      <link rel="stylesheet" type="text/css" href="common.css">
      <style>
          .bg-img-div {
              width: 100%;
              height: 100%;
              position: absolute;
              transform: translate(0px, 0px);
              background-size: 100% 159px;
              background-image: none;
              background-position: 0 0;
              z-index: 0;
  
          }
  
          .slider-img-div {
              height: 100%;
              width: 100%;
              background-size: 100% 159px;
              position: absolute;
              transform: translate(0px, 0px);
              /*border-bottom: 1px solid blue;*/
              z-index: 1;
          }
      </style>
  </head>
  
  <body>
  <div class="slider">
      <div class="content">
          <div class="slider-img-div" id="slider-img-div">
              <img id="slider-img" src="" alt/>
          </div>
          <div class="bg-img-div">
          </div>
      </div>
      <div class="slider-move">
          <div class="slider-move-track">
              拖动滑块完成拼图
          </div>
          <div class="slider-move-btn" id="slider-move-btn"></div>
      </div>
      <div class="bottom">
          <div class="close-btn" id="slider-close-btn"></div>
          <div class="refresh-btn" id="slider-refresh-btn"></div>
      </div>
  </div>
  <script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
  <script src="index.js"></script>
  <script src="concat.js"></script>
  </body>
  </html>
  
  

• js

  var currentCaptchaId;
  $(function () {
      refreshCaptcha();
      clearAllPreventDefault($(".slider"));
  })
  
  $("#slider-move-btn").mousedown(down);
  $("#slider-move-btn").on("touchstart", down);
  
  function doDown() {
      $("#slider-move-btn").css("background-position", "-5px 31.0092%")
  }
  
  function doMove(config) {
      const moveX = config.moveX;
      $("#slider-move-btn").css("transform", "translate(" + moveX + "px, 0px)")
      $("#slider-img-div").css("background-position-x", moveX + "px");
  }
  
  $("#slider-close-btn").click(() => {
  });
  
  $("#slider-refresh-btn").click(() => {
      refreshCaptcha();
  });
  
  function valid(captchaConfig) {
  
      let data = {
          'id' : currentCaptchaId,
          'captchaTrack': {
              bgImageWidth: captchaConfig.bgImageWidth,
              bgImageHeight: captchaConfig.bgImageHeight,
              sliderImageWidth: captchaConfig.sliderImageWidth,
              sliderImageHeight: captchaConfig.sliderImageHeight,
              startSlidingTime: captchaConfig.startTime,
              endSlidingTime: captchaConfig.stopTime,
              trackList: captchaConfig.trackArr
          }
      }
     
      $.ajax({
          type:"POST",
          url:"http://localhost:8080/check",
          contentType: "application/json", 
          dataType:"json",
          data:JSON.stringify(data),
          success:function (res) {
              if (res) {
                  alert("验证成功!!!");
              }
              refreshCaptcha();
          }
      })
  }
  
  function refreshCaptcha() {
      $.get("http://localhost:8080/index?type=CONCAT", function (data) {
          reset();
          currentCaptchaId = data.id;
          const bgImg = $(".bg-img-div");
          const sliderImg = $(".slider-img-div");
  
          bgImg.css("background-image", "url(" + data.captcha.backgroundImage + ")");
          sliderImg.css("background-image", "url(" + data.captcha.backgroundImage + ")");
          sliderImg.css("background-position", "0px 0px");
          var backgroundImageHeight = data.captcha.backgroundImageHeight;
          var height = ((backgroundImageHeight - data.captcha.data) / backgroundImageHeight) * 159;
          $(".slider-img-div").css("height", height);
  
          initConfig(bgImg.width(), bgImg.height(), sliderImg.width(), sliderImg.height(), 206);
      })
  }
  
  function reset() {
      $("#slider-move-btn").css("background-position", "-5px 11.79625%")
      $("#slider-move-btn").css("transform", "translate(0px, 0px)")
      $("#slider-img-div").css("transform", "translate(0px, 0px)")
      currentCaptchaId = null;
  }
  

• 最终结果

2.5 文字点选验证码

• html

  <!DOCTYPE html>
  <html lang="en">
  <head>
      <meta charset="UTF-8">
      <meta http-equiv="X-UA-Compatible" content="IE=edge">
      <meta name="viewport" content="width=device-width, initial-scale=1.0">
      <title>文字点选验证码</title>
      <link rel="stylesheet" type="text/css" href="common.css">
      <style>
          .tip-img {
              width: 130px;
              position: absolute;
              right: 5px;
          }
  
          .slider-move-span {
              font-size: 18px;
              display: inline-block;
              height: 40px;
              line-height: 40px;
          }
  
          .click-span {
              position: absolute;
              left: 0;
              top: 0;
              border-radius: 50px;
              background-color: #409eff;
              width: 20px;
              height: 20px;
              text-align: center;
              line-height: 20px;
              color: #fff;
              border: 2px solid #fff;
          }
  
          .submit-btn {
              height: 40px;
              width: 120px;
              line-height: 40px;
              text-align: center;
              background-color: #409eff;
              color: #fff;
              font-size: 15px;
              box-sizing: border-box;
              border: 1px solid #409eff;
              float: right;
              border-radius: 5px;
          }
      </style>
  </head>
  
  <body>
  <div class="slider">
      <div class="slider-move">
          <span class="slider-move-span">请依次点击:</span><img src="" class="tip-img">
      </div>
      <div class="content">
          <div class="bg-img-div">
              <img id="bg-img" src="" alt/>
          </div>
          <div class="bg-click-div">
          </div>
      </div>
      <div class="bottom">
          <div class="close-btn" id="slider-close-btn"></div>
          <div class="refresh-btn" id="slider-refresh-btn"></div>
      </div>
  </div>
  <script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
  <script src="word-click.js"></script>
  </body>
  </html>
  

• js

  let start = 0;
  let startY = 0;
  let currentCaptchaId = null;
  let movePercent = 0;
  const bgImgWidth = $(".bg-img-div").width();
  let end = 206;
  let startSlidingTime;
  let entSlidingTime;
  const trackArr = [];
  let clickCount = 0;
  $(function () {
      refreshCaptcha();
  })
  $(".content").click(function (event) {
      console.log(event);
      clickCount++;
      if (clickCount === 1) {
          startSlidingTime = new Date();
          // move 轨迹
          window.addEventListener("mousemove", move);
      }
      trackArr.push({
          x: event.offsetX,
          y: event.offsetY,
          type: "click",
          t: (new Date().getTime() - startSlidingTime.getTime())
      });
      const left = event.offsetX - 10;
      const top = event.offsetY - 10;
      $(".bg-click-div").append("<span class='click-span' style='left:" + left + "px;top: " + top + "px'>" + clickCount + "</span>")
      if (clickCount === 4) {
          // 校验
          entSlidingTime = new Date();
          window.removeEventListener("mousemove", move);
          valid();
      }
  });
  
  function move(event) {
      if (event instanceof TouchEvent) {
          event = event.touches[0];
      }
      console.log("x:", event.offsetX, "y:", event.offsetY, "time:" ,new Date().getTime() - startSlidingTime.getTime());
      trackArr.push({x: event.offsetX, y:event.offsetY, t: (new Date().getTime() - startSlidingTime.getTime()), type: "move"});
  }
  
  
  $("#slider-close-btn").click(() => {
  });
  
  $("#slider-refresh-btn").click(() => {
      refreshCaptcha();
  });
  
  function valid() {
     
      let data = {
          'id': currentCaptchaId,
          'captchaTrack': {
              bgImageWidth: $(".bg-img-div").width(),
              bgImageHeight: $(".content").height(),
              sliderImageWidth: -1,
              sliderImageHeight: -1,
              startSlidingTime: startSlidingTime,
              entSlidingTime: entSlidingTime,
              trackList: trackArr
          }
      };
      
      $.ajax({
          type:"POST",
          url:"http://localhost:8080/check",
          contentType: "application/json", 
          dataType:"json",
          data:JSON.stringify(data),
          success:function (res) {
              if (res) {
                  alert("验证成功!!!");
              }
              refreshCaptcha();
          }
      })
  }
  
  function refreshCaptcha() {
      $.get("http://localhost:8080/index?type=WORD_IMAGE_CLICK", function (data) {
          reset();
          currentCaptchaId = data.id;
          $("#bg-img").attr("src", data.captcha.backgroundImage);
          $("#slider-img").attr("src", data.captcha.sliderImage);
          $(".tip-img").attr("src", data.captcha.sliderImage);
      })
  }
  
  function reset() {
      $("#slider-move-btn").css("background-position", "-5px 11.79625%")
      $("#slider-move-btn").css("transform", "translate(0px, 0px)")
      $("#slider-img-div").css("transform", "translate(0px, 0px)")
      start = 0;
      startSlidingTime = null;
      entSlidingTime = null;
      trackArr.length = 0;
      $(".bg-click-div span").remove();
      clickCount = 0;
      movePercent = 0;
      currentCaptchaId = null;
      startY = 0;
      window.removeEventListener("mousemove", move);
  }
  

• 最终结果

  

三、源码探秘和总结

3.1 前端代码

前端代码部分主要是传递用户鼠标数据给后端，可以根据滑动和点选分为两种

• 滑动

  滑动数据主要逻辑部分就在通用js代码中，主要就是三个函数，用户鼠标按下，移动，抬起三种操作的监听函数

• 点选

  点选和滑动不一样，需要记录点击4个汉字的坐标，然后传递给后端

3.2 后端代码

下面会对上述验证码后端生成，校验和存储进行源码探秘

• 滑块验证码

  滑块验证码的图片生成部分可以见：StandardSliderImageCaptchaGenerator.doGenerateCaptchaImage方法，随机从模板获取背景图片，再用滑块的图片，选择随机x,y坐标覆盖掉

  // 获取随机的 x 和 y 轴
  int randomX = ThreadLocalRandom.current().nextInt(fixedTemplate.getWidth() + 5, targetBackground.getWidth() - fixedTemplate.getWidth() - 10);
  int randomY = ThreadLocalRandom.current().nextInt(targetBackground.getHeight() - fixedTemplate.getHeight());
  
  CaptchaImageUtils.overlayImage(targetBackground, fixedTemplate, randomX, randomY);
  if (obfuscate) {
      // 加入混淆滑块
      int obfuscateX = randomObfuscateX(randomX, fixedTemplate.getWidth(), targetBackground.getWidth());
      CaptchaImageUtils.overlayImage(targetBackground, fixedTemplate, obfuscateX, randomY);
  }
  BufferedImage cutImage = CaptchaImageUtils.cutImage(cutBackground, fixedTemplate, randomX, randomY);
  CaptchaImageUtils.overlayImage(cutImage, activeTemplate, 0, 0);
  CaptchaImageUtils.overlayImage(matrixTemplate, cutImage, 0, randomY);
  return wrapSliderCaptchaInfo(randomX, randomY, targetBackground, matrixTemplate, param);
  

• 旋转验证码

  生成部分可以见：StandardRotateImageCaptchaGenerator.doGenerateCaptchaImage 方法，选择居中部分抠出旋转随机角度

  // 算出居中的x和y
  int x = targetBackground.getWidth() / 2 - fixedTemplate.getWidth() / 2;
  int y = targetBackground.getHeight() / 2 - fixedTemplate.getHeight() / 2;
  CaptchaImageUtils.overlayImage(targetBackground, fixedTemplate, x, y);
  // 抠图部分
  BufferedImage cutImage = CaptchaImageUtils.cutImage(cutBackground, fixedTemplate, x, y);
  CaptchaImageUtils.overlayImage(cutImage, activeTemplate, 0, 0);
  // 随机旋转抠图部分
  // 随机x， 转换为角度
  int randomX = ThreadLocalRandom.current().nextInt(fixedTemplate.getWidth() + 10, targetBackground.getWidth() - 10);
  double degree = 360d - randomX / ((targetBackground.getWidth()) / 360d);
  CaptchaImageUtils.centerOverlayAndRotateImage(matrixTemplate, cutImage, degree);
  return wrapRotateCaptchaInfo(degree, randomX, targetBackground, matrixTemplate, param);
  

• 滑块还原验证码

  生成部分可以见：StandardConcatImageCaptchaGenerator.doGenerateCaptchaImage 方法, 选择1/4-3/4高度随机值作为y坐标，这是切割部分，将图片切断成两部分，上面是可滑动的。1/8-4/5宽度随机值作为x坐标，这是x轴分隔点

  Resource resourceImage = imageCaptchaResourceManager.randomGetResource(param.getType());
  InputStream resourceInputStream = imageCaptchaResourceManager.getResourceInputStream(resourceImage);
  inputStreams.add(resourceInputStream);
  BufferedImage bgImage = wrapFile2BufferedImage(resourceInputStream);
  int spacingY = bgImage.getHeight() / 4;
  int randomY = ThreadLocalRandom.current().nextInt(spacingY, bgImage.getHeight() - spacingY);
  BufferedImage[] bgImageSplit = splitImage(randomY, true, bgImage);
  int spacingX = bgImage.getWidth() / 8;
  int randomX = ThreadLocalRandom.current().nextInt(spacingX, bgImage.getWidth() - bgImage.getWidth() / 5);
  BufferedImage[] bgImageTopSplit = splitImage(randomX, false, bgImageSplit[0]);
  
  BufferedImage sliderImage = concatImage(true,
                                          bgImageTopSplit[0].getWidth()
                                          + bgImageTopSplit[1].getWidth(), bgImageTopSplit[0].getHeight(), bgImageTopSplit[1], bgImageTopSplit[0]);
  bgImage = concatImage(false, bgImageSplit[1].getWidth(), sliderImage.getHeight() + bgImageSplit[1].getHeight(),
                        sliderImage, bgImageSplit[1]);
  return wrapConcatCaptchaInfo(randomX, randomY, bgImage, param);
  

• 文字点选验证码

  通用生成部分可以见：AbstractClickImageCaptchaGenerator.doGenerateCaptchaImage 方法, 具体文字生成部分可以见StandardRandomWordClickImageCaptchaGenerator.genTipImage。

  生成的文字个数由变量 checkClickCount=4控制，已在代码中写死，后面是否可以做成配置？

  List<ClickImageCheckDefinition> clickImageCheckDefinitionList = new ArrayList<>(interferenceCount);
  int allImages = interferenceCount + checkClickCount;
  int avg = bgImage.getWidth() / allImages;
  List<String> imgTips = randomGetClickImgTips(allImages);
  if (allImages < imgTips.size()) {
      throw new IllegalStateException("随机生成点击图片小于请求数量， 请求生成数量=" + allImages + ",实际生成数量=" + imgTips.size());
  }
  for (int i = 0; i < allImages; i++) {
      // 随机获取点击图片
      ImgWrapper imgWrapper = getClickImg(imgTips.get(i));
      BufferedImage image = imgWrapper.getImage();
      int clickImgWidth = image.getWidth();
      int clickImgHeight = image.getHeight();
      // 随机x
      int randomX;
      if (i == 0) {
          randomX = 1;
      } else {
          randomX = avg * i;
      }
      // 随机y
      int randomY = ThreadLocalRandom.current().nextInt(10, bgImage.getHeight() - clickImgHeight);
      // 通过随机x和y 进行覆盖图片
      CaptchaImageUtils.overlayImage(bgImage, imgWrapper.getImage(), randomX, randomY);
      ClickImageCheckDefinition clickImageCheckDefinition = new ClickImageCheckDefinition();
      clickImageCheckDefinition.setTip(imgWrapper.getTip());
      clickImageCheckDefinition.setX(randomX + clickImgWidth / 2);
      clickImageCheckDefinition.setY(randomY + clickImgHeight / 2);
      clickImageCheckDefinition.setWidth(clickImgWidth);
      clickImageCheckDefinition.setHeight(clickImgHeight);
      clickImageCheckDefinitionList.add(clickImageCheckDefinition);
  }
  List<ClickImageCheckDefinition> checkClickImageCheckDefinitionList = getCheckClickImageCheckDefinitionList(clickImageCheckDefinitionList,checkClickCount);
  return wrapClickImageCaptchaInfo(param, bgImage, checkClickImageCheckDefinitionList);
  
  

• 校验验证码

  校验部分可以根据滑动还是点选分为两种

  • 滑块

    源码主要实现部分位于SimpleImageCaptchaValidator.doValidSliderCaptcha方法，目前只校验最后一个轨迹是否到达缺口处，没有对所有轨迹进行行为校验

    public boolean doValidSliderCaptcha(ImageCaptchaTrack imageCaptchaTrack,
                                        Map<String, Object> sliderCaptchaValidData,
                                        Float tolerant,
                                        String type) {
        Float oriPercentage = getFloatParam(PERCENTAGE_KEY, sliderCaptchaValidData);
        if (oriPercentage == null) {
            // 没读取到百分比
            return false;
        }
        List<ImageCaptchaTrack.Track> trackList = imageCaptchaTrack.getTrackList();
        // 取最后一个滑动轨迹
        ImageCaptchaTrack.Track lastTrack = trackList.get(trackList.size() - 1);
        // 计算百分比
        float calcPercentage = calcPercentage(lastTrack.getX(), imageCaptchaTrack.getBgImageWidth());
        // 校验百分比
        return checkPercentage(calcPercentage, oriPercentage, tolerant);
    }
    

  • 点选

    源码实现部分位于SimpleImageCaptchaValidator.doValidClickCaptcha方法，可以看到按照顺序对点选轨迹依次进行XY坐标进行百分比校验，默认有2%的容错

    public boolean doValidClickCaptcha(ImageCaptchaTrack imageCaptchaTrack,
                                       Map<String, Object> sliderCaptchaValidData,
                                       Float tolerant,
                                       String type) {
        String validStr = getStringParam(PERCENTAGE_KEY, sliderCaptchaValidData, null);
        if (ObjectUtils.isEmpty(validStr)) {
            return false;
        }
        String[] splitArr = validStr.split(";");
        List<ImageCaptchaTrack.Track> trackList = imageCaptchaTrack.getTrackList();
        if (trackList.size() < splitArr.length) {
            return false;
        }
        // 取出点击事件的轨迹数据
        List<ImageCaptchaTrack.Track> clickTrackList = trackList
            .stream()
            .filter(t -> TrackTypeConstant.CLICK.equalsIgnoreCase(t.getType()))
            .collect(Collectors.toList());
        if (clickTrackList.size() != splitArr.length) {
            return false;
        }
        for (int i = 0; i < splitArr.length; i++) {
            ImageCaptchaTrack.Track track = clickTrackList.get(i);
            String posStr = splitArr[i];
            String[] posArr = posStr.split(",");
            float xPercentage = Float.parseFloat(posArr[0]);
            float yPercentage = Float.parseFloat(posArr[1]);
    
            float calcXPercentage = calcPercentage(track.getX(), imageCaptchaTrack.getBgImageWidth());
            float calcYPercentage = calcPercentage(track.getY(), imageCaptchaTrack.getBgImageHeight());
    
            if (!checkPercentage(calcXPercentage, xPercentage, tolerant)
                || !checkPercentage(calcYPercentage, yPercentage, tolerant)) {
                return false;
            }
        }
        return true;
    }
    

• 存储部分

  验证码存储部分主要接口为 CacheStore，如果项目中引入了redis ，那么会使用redis来存储，否则会使用本地存储

  @Configuration(proxyBeanMethods = false)
  @ConditionalOnClass(StringRedisTemplate.class)
  @Import({RedisAutoConfiguration.class})
  @AutoConfigureAfter({RedisAutoConfiguration.class})
  public static class RedisCacheStoreConfiguration {
  
      @Bean
      @ConditionalOnBean(StringRedisTemplate.class)
      @ConditionalOnMissingBean(CacheStore.class)
      public CacheStore redis(StringRedisTemplate redisTemplate) {
          return new RedisCacheStore(redisTemplate);
      }
  }
  
  @Configuration(proxyBeanMethods = false)
  @AutoConfigureAfter({RedisCacheStoreConfiguration.class})
  @Import({RedisCacheStoreConfiguration.class})
  public static class LocalCacheStoreConfiguration {
  
      @Bean
      @ConditionalOnMissingBean(CacheStore.class)
      public CacheStore local() {
          return new LocalCacheStore();
      }
  }
  

3.3 总结

• 目前这个库只提供4种行为验证码，不过在后端源码验证码类型CaptchaTypeConstant 中发现了图片点选的常量，后续版本应该会加上图片点选的验证码，这种很常见，使用梯子访问谷歌时经常会碰到这种，要用户选择红绿灯、摩托车等等。
• 最后，感谢作者将如此棒的库开源，已 starred

参考

1. https://gitee.com/tianai/tianai-captcha-demo