当用户发布电子邮件时，我只想在同一用户发送电子邮件请求之前超过 1 分钟才发送邮件。我怎样才能做到这一点？答案

【问题标题】：when user posts email, I want to send mail only if more than 1 minute passed before same users send email request. how can I do that?当用户发布电子邮件时，我只想在同一用户发送电子邮件请求之前超过 1 分钟才发送邮件。我怎样才能做到这一点？
【发布时间】：2021-11-25 16:40:24
【问题描述】：

@RequestMapping( value = "/resendMail", method = RequestMethod.POST)
public ApiException sendMail(@Valid @RequestBody EmailRequest emailRequest) {
    ApiException response = null;
    User user = userRepository.findByEmail(emailRequest.getEmail());
    if( user!=null) {
        // If 1 minute passed do this.
        userService.sendVerificationEmail(user, user.getEmail());
        response = new ApiException("Link sent to this email,", null, HttpStatus.OK);
    }
}

这是我的服务。如果用户在 60 秒内没有发送请求，我想这样做：

SimpleMailMessage simpleMailMessage =new SimpleMailMessage();
simpleMailMessage.setFrom(from);
simpleMailMessage.setTo(to);
simpleMailMessage.setSubject(subject);
simpleMailMessage.setText(content+"http://localhost:8080/confirm-email?id="+ user.getId());
try {
    mailSender.send(simpleMailMessage);
} catch (MailException mailException) {

}

【问题讨论】：

您是否需要在同一个请求中执行此操作，异步或添加特定队列以供其他应用读取？您可以使用代理模式，并在简单的static var new ConcurrentHashMap<LocalDateTime,ObjectToResendEmail>(); 中管理您的逻辑，或者您可以使用 Spring Boot 中的 @Async 注释来并行化您的流程，或者使用事件驱动的队列、bacth、其他应用程序（ sugeested in a large scalabitity )

标签： java spring spring-boot time spring-data-jpa

【解决方案1】：

您可以简单地将 lastEmailSentDate 存储在 UserEntity 类中作为 LocalDateTime。

还为此创建存储库并实现邮件发送：

UserServiceImpl：

public boolean sendVerificationEmvail(UserEntity user){
    LocalDateTime last = user.getLastEmailSentDate();
    if(Objects.isNull(last) || !last.minusMinutes(1L).before(LocalDateTime.now())){
        return false;
    }

    user.setLastEmailSentDate(LocalDateTime.now());

    //Mail sending logic here

    userRepository.save(user);

    return true;
}

控制器：

@RequestMapping( value = "/resendMail", method = RequestMethod.POST)
public ApiException sendMail(@Valid @RequestBody EmailRequest emailRequest) {
    ApiException response = null;
    User user = userRepository.findByEmail(emailRequest.getEmail());
    if( user!=null) {
        if(userService.sendVerificationEmail(user)){
            response = new ApiException("Link sent to this email,", null, HttpStatus.OK);
        }
    }
}

【讨论】：