1. Overview

In this tutorial – we’re continuing the ongoing Registration with Spring Security series with a look at resending the verification link to the user in case it expires before they have a chance to activate their account.

2. Resend the Verification Link

First, let’s see we what happens when the user requests another verification link, in case the previous one expired.

First – we’ll reset the existing token with a new expireDate. The, we’ll send the user a new email, with the new link/token:

@GetMapping("/user/resendRegistrationToken")
public GenericResponse resendRegistrationToken(
 HttpServletRequest request, @RequestParam("token") String existingToken) {
 VerificationToken newToken = userService.generateNewVerificationToken(existingToken);
 
 User user = userService.getUser(newToken.getToken());
 String appUrl = 
 "http://" + request.getServerName() + 
 ":" + request.getServerPort() + 
 request.getContextPath();
 SimpleMailMessage email = 
 constructResendVerificationTokenEmail(appUrl, request.getLocale(), newToken, user);
 mailSender.send(email);

 return new GenericResponse(
 messages.getMessage("message.resendToken", null, request.getLocale()));
}

And the utility for actually building the email message the user gets – constructResendVerificationTokenEmail():

private SimpleMailMessage constructResendVerificationTokenEmail
 (String contextPath, Locale locale, VerificationToken newToken, User user) {
 String confirmationUrl = 
 contextPath + "/regitrationConfirm.html?token=" + newToken.getToken();
 String message = messages.getMessage("message.resendToken", null, locale);
 SimpleMailMessage email = new SimpleMailMessage();
 email.setSubject("Resend Registration Token");
 email.setText(message + " rn" + confirmationUrl);
 email.setFrom(env.getProperty("support.email"));
 email.setTo(user.getEmail());
 return email;
}

We also need to modify the existing registration functionality – by adding some new information on the model about the expiration of the token:

@GetMapping("/registrationConfirm")
public String confirmRegistration(
 Locale locale, Model model, @RequestParam("token") String token) {
 VerificationToken verificationToken = userService.getVerificationToken(token);
 if (verificationToken == null) {
 String message = messages.getMessage("auth.message.invalidToken", null, locale);
 model.addAttribute("message", message);
 return "redirect:/badUser.html?lang=" + locale.getLanguage();
 }

 User user = verificationToken.getUser();
 Calendar cal = Calendar.getInstance();
 if ((verificationToken.getExpiryDate().getTime() - cal.getTime().getTime()) <= 0) {
 model.addAttribute("message", messages.getMessage("auth.message.expired", null, locale));
 model.addAttribute("expired", true);
 model.addAttribute("token", token);
 return "redirect:/badUser.html?lang=" + locale.getLanguage();
 }

 user.setEnabled(true);
 userService.saveRegisteredUser(user);
 model.addAttribute("message", messages.getMessage("message.accountVerified", null, locale));
 return "redirect:/login.html?lang=" + locale.getLanguage();
}

3. Exception Handler

The previous functionality is, under certain conditions – throwing exceptions; these exceptions need to be handled, and we’re going to do that with a custom exception handler:

@ControllerAdvice
public class RestResponseEntityExceptionHandler extends ResponseEntityExceptionHandler {

 @Autowired
 private MessageSource messages;

 @ExceptionHandler({ UserNotFoundException.class })
 public ResponseEntity<Object> handleUserNotFound(RuntimeException ex, WebRequest request) {
 logger.error("404 Status Code", ex);
 GenericResponse bodyOfResponse = new GenericResponse(
 messages.getMessage("message.userNotFound", null, request.getLocale()), "UserNotFound");
 
 return handleExceptionInternal(
 ex, bodyOfResponse, new HttpHeaders(), HttpStatus.NOT_FOUND, request);
 }

 @ExceptionHandler({ MailAuthenticationException.class })
 public ResponseEntity<Object> handleMail(RuntimeException ex, WebRequest request) {
 logger.error("500 Status Code", ex);
 GenericResponse bodyOfResponse = new GenericResponse(
 messages.getMessage(
 "message.email.config.error", null, request.getLocale()), "MailError");
 
 return handleExceptionInternal(
 ex, bodyOfResponse, new HttpHeaders(), HttpStatus.NOT_FOUND, request);
 }

 @ExceptionHandler({ Exception.class })
 public ResponseEntity<Object> handleInternal(RuntimeException ex, WebRequest request) {
 logger.error("500 Status Code", ex);
 GenericResponse bodyOfResponse = new GenericResponse(
 messages.getMessage(
 "message.error", null, request.getLocale()), "InternalError");
 
 return handleExceptionInternal(
 ex, bodyOfResponse, new HttpHeaders(), HttpStatus.NOT_FOUND, request);
 }
}

Note that:

• we used @ControllerAdvice annotation to handle exceptions across the whole application
• we used a simple object GenericResponse to send the response:

public class GenericResponse {
 private String message;
 private String error;

 public GenericResponse(String message) {
 super();
 this.message = message;
 }

 public GenericResponse(String message, String error) {
 super();
 this.message = message;
 this.error = error;
 }
}

4. Modify badUser.html

We’ll now modify badUser.html by enabling the user to get a new VerificationToken only if their token expired:

<html>
<head>
<title th:text="#{label.badUser.title}">bad user</title>
</head>
<body>
<h1 th:text="${param.message[0]}">error</h1>
<br>
<a th:href="@{/user/registration}" th:text="#{label.form.loginSignUp}">
 signup</a>

<div th:if="${param.expired[0]}">
<h1 th:text="#{label.form.resendRegistrationToken}">resend</h1>
<button onclick="resendToken()" 
 th:text="#{label.form.resendRegistrationToken}">resend</button>
 
<script src="jquery.min.js"></script>
<script type="text/javascript">

var serverContext = [[@{/}]];

function resendToken(){
 $.get(serverContext + "user/resendRegistrationToken?token=" + token, 
 function(data){
 window.location.href = 
 serverContext +"login.html?message=" + data.message;
 })
 .fail(function(data) {
 if(data.responseJSON.error.indexOf("MailError") > -1) {
 window.location.href = serverContext + "emailError.html";
 }
 else {
 window.location.href = 
 serverContext + "login.html?message=" + data.responseJSON.message;
 }
 });
}
</script>
</div>
</body>
</html>

Notice that we’ve used some very basic javascript and JQuery here to handle the response of “/user/resendRegistrationToken” and redirect the user based on it.

5. Conclusion

In this quick article we allowed the user to request a new verification link to activate their account, in case the old one expired.