Integration reCaptcha with Spring MVC

When I was explaining about reCaptcha on my previous entry, I made reference to my little-store example app, which basically has a bunch of frameworks (the idea is implement those technologies that I want to learn or just practice).

What I did is really simple, the first step was adding my new dependency to my POM <dependency> <groupId>net.tanesha.recaptcha4j</groupId> <artifactId>recaptcha4j</artifactId> <version>0.0.7</version> </dependency>
Then add to my webApplicationContext.xml my new reCaptcha bean <!-- Creates reCaptcha Instance --> <bean id="reCaptcha" class="net.tanesha.recaptcha.ReCaptchaImpl"> <property name="privateKey" value="${recaptcha.private.key}" /> <property name="publicKey" value="${recaptcha.public.key}" /> <property name="includeNoscript" value="false" /> </bean>
You must get the keys from the official website by adding your site. On my case I put the keys in a properties file, and then by using spring I loaded that file
<context:property-placeholder location="classpath:my-application.properties"/>

Next in my Controller I used my ReCaptcha bean, like this @Controller @RequestMapping("/checkOut/*") public class CheckOutController extends BaseCustomController { ... @Autowired private ReCaptcha reCaptcha; @RequestMapping(value="addPaymentInformation.do", method=RequestMethod.POST) public String addPaymentInfo(HttpServletRequest request, ModelMap modelMap, @ModelAttribute("CreditCardDTO") CreditCardDTO paramCreditCardDTO, Object skipUpdateCreditCard){ ... //Displays reCatcha modelMap.put("reCaptcha", reCaptcha.createRecaptchaHtml(request.getParameter("error"), null)); return "checkout/confirm_order"; }
As you could see, this code populates a variable (reCaptcha) which I'm going to display on my JSP using JSTL:

${requestScope.reCaptcha}

Inside of a HTML FORM

Finally, this is how I validated the confirmation text (you must be expecting these 2 params: recaptcha_challenge_field and recaptcha_response_field)
@RequestMapping(value="submitOrderAndPayment.do", method=RequestMethod.POST) public String submitOrderWithPayment(HttpServletRequest request, ModelMap modelMap, @RequestParam("idCreditCard") final Integer idCreditCard, @RequestParam("recaptcha_challenge_field") final String reCaptchaChallenge, @RequestParam("recaptcha_response_field") final String reCaptchaResponse){ ... //Handles reCaptcha ReCaptchaResponse response = reCaptcha.checkAnswer(request.getRemoteAddr(), reCaptchaChallenge, reCaptchaResponse); if(!response.isValid()){ log.warn("reCaptcha Answer msg= "+response.getErrorMessage()); modelMap.put("reCaptchaError",response.getErrorMessage()); return addPaymentInfo(request, modelMap, creditCardDTO, Boolean.TRUE); } ... //It was correct, then proceed //Show confirmation page, it shows order number return "checkout/order_completed"; }
The only problem I faced was related to my flow (which screen should I display), but besides that the implementation is really straight forward, simple!