kaptcha-spring-boot-starter

Kaptcha for spring boot autoconfigure.

1. Maven

<dependency>
    <groupId>com.youkol.support.kaptcha</groupId>
    <artifactId>kaptcha-spring-boot-starter</artifactId>
    <version>LATEST_VERSION</version>
</dependency>

2. Config spring-boot application.yml

# Support zero-configuration mode, it will running by the default value.
# For Example:
youkol:
  web:
    kaptcha:
      enabled: true
      servlet:
        enabled: true
        url-mapping: /kaptcha
        size-param: size
        font-size-param: fontSize
      cache:
        # cache.type = session or redis.
        type: session
        token-name: YOUKOL-KAPTCHA-TOKEN
        timeout: 300000
      config:
        kaptcha:
          #
          # Note: To avoid syntax errors in yaml files,
          #       when border property is "no", don't set value of border color and border thickness.
          #       when border property is "yes", You must omit the border property setting and
          #       set value of border color and border thickness directly.
          #
          #       Take a look at the following example:
          #           1) Hide border
          border: "no"
          #           2) Show border
          # border:
          #   color: "105,179,90"
          #   thickness: 1
          producer:
            impl: com.google.code.kaptcha.impl.DefaultKaptcha
          textproducer:
            # simple math text creator, for example `7+8=?`
            # impl: com.youkol.support.kaptcha.text.impl.SimpleMathTextCreator
            impl: com.google.code.kaptcha.text.impl.DefaultTextCreator
            char:
              string: abcde2345678gfynmnpwx
              length: 5
              space: 2
            font:
              names: \u5fae\u8f6f\u96c5\u9ed1,Arial,\u5b8b\u4f53,\u6977\u4f53
              size: 40
              color: BLUE
          noise:
            impl: com.google.code.kaptcha.impl.NoNoise
            color: BLACK
          obscurificator:
            impl: com.google.code.kaptcha.impl.WaterRipple
          word:
            impl: com.youkol.support.kaptcha.text.impl.SimpleWordRenderer
          background:
            impl: com.google.code.kaptcha.impl.DefaultBackground
            clear:
              from: LIGHT_GRAY
              to: WHITE
          image:
            width: 200
            height: 50

3. Send Request Url

GET http(s)://{host}:{port}/{contextPath}/{urlMapping}
For example:

response image

Request: GET http://localhost:8080/kaptcha
Response: kaptcha image (image/jpeg)

response json

Request: GET http://localhost:8080/kaptcha?format=base64
Response:

  {   
    "code": "200",    
    "message": "OK",    
    "data": {    
      "uuid": "f7e7001f042a47eaa73dcdafe01a7b9d",    
      "image": "data:image/jpeg;base64,/9j/4AA...RRRQB//9k="   
    }
  }

4. validate image code

sample code:

// For example:
@Autowired
private KaptchaCacheResolver kaptchaCacheResolver;

public Object login(HttpServletRequest request) {
    // some things.
    // valid Kaptcha
    String code = request.getParameter("code");
    boolean bValid = kaptchaCacheResolver.validKaptcha(request, code);
    // other things.
}

Note: when use redis mode, you must put token-name and token-value in request header.

token-name: youkol.web.kaptcha.cache.token-name
token-value: the uuid of response (The uuid also can get from response header)

About Kaptcha