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Partner – Moderne – NPI EA (cat=Spring Boot)
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Course – LSS – NPI (cat=Spring Security)
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If you're working on a Spring Security (and especially an OAuth) implementation, definitely have a look at the Learn Spring Security course:

>> LEARN SPRING SECURITY

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.

The code backing this article is available on GitHub. Once you're logged in as a Baeldung Pro Member, start learning and coding on the project.
Next »
Registration with Spring Security – Password Encoding
« Previous
Registration – Activate a New Account by Email
Baeldung Pro – NPI EA (cat = Baeldung)
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eBook – HTTP Client – NPI EA (cat=HTTP Client-Side)
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eBook – Java Concurrency – NPI EA (cat=Java Concurrency)
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eBook – Java Streams – NPI EA (cat=Java Streams)
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Since its introduction in Java 8, the Stream API has become a staple of Java development. The basic operations like iterating, filtering, mapping sequences of elements are deceptively simple to use.

But these can also be overused and fall into some common pitfalls.

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eBook – Persistence – NPI EA (cat=Persistence)
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eBook Jackson – NPI EA – 3 (cat = Jackson)