Schedule a function in spring boot with #Scheduled annotation - spring

Question

I would like to execute the following method at the date and time speified on my Angular form
-Here is the input:
<input required [(ngModel)]="emailNotification.sendingDate" class="form-control" type="datetime-local" name="sendingDate" id="time">
The sending emails method(from the controller)
#PostMapping(value="/getdetails")
public #ResponseBody void sendMail(#RequestBody EmailNotification details) throws Exception {
try {
JavaMailSenderImpl jms = (JavaMailSenderImpl) sender;
MimeMessage message = jms.createMimeMessage();
MimeMessageHelper helper = new MimeMessageHelper(message, MimeMessageHelper.MULTIPART_MODE_MIXED_RELATED, StandardCharsets.UTF_8.name());
helper.setFrom("smsender4#gmail.com");
List<String> recipients = fileRepo.findWantedEmails(details.getDaysNum());
String[] to = recipients.stream().toArray(String[]::new);
helper.setTo(to);
helper.setText(details.getMessage(),true);
helper.setSubject("Test Mail");
details.setRecipients(to);
sender.send(message);
enr.save(new EmailNotification(details.getId(), "Test mail", details.getMessage(), details.getDaysNum(), details.getRecipients(), details.getSendingDate()));
} catch (MessagingException e) {
throw new RuntimeException("fail to send emails: " + e.getMessage());
}
EmailNotification.class
public class EmailNotification {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private long id;
private String subject;
private String message;
private int daysNum;
private String[] recipients;
/*
* #Temporal(TemporalType.TIMESTAMP)
*/
//"yyyy-MM-dd'T'HH:mm:ss.SSSX"
#Column(name = "sending_date")
#Basic(fetch = FetchType.EAGER)
private LocalDateTime sendingDate;
public EmailNotification(long id, String subject,String message, int daysNum, String[] recipients, LocalDateTime sendingDate) {
super();
this.sendingDate = sendingDate;
this.daysNum = daysNum;
this.id = id;
this.message = message;
this.subject = subject;
}
I don't know how to proceed, Iùll be so gratefull if someone helped

Answer 1

Now I think I understand what you are trying to achieve, so check if this works for you.
Let's say you want to send an email when in the given table (I will name it PAYMENT), there's 5 days left for the deadline. Let's say this table has an equivalent entity class named Payment, you could do something like this:
Asumming the Payment entity has it's own CrudRepository extention, which you are using to access the dabatase, you would make a query to find the payments close to the deadline. This of course will depend on how you are accessing your database. The next example query probably won't work (because as far as I know, JPA doesn't support DATEDIFF), but will work as base for what you are trying to achieve
#Repository
public interface PaymentRepository extends CrudRepository<Payment, Integer> {
/* You need to find every payment that's 5 days from the deadline */
#Query("SELECT p FROM PAYMENT p WHERE DATEDIFF(day, CURRENT_TIMESTAMP, p.deadline) <= 5")
public List<PaymentRepository> findPaymentsCloseToDeadline();
}
Make a scheduled task class that sends the email for every payment close to the deadline. Instead of passing parameters to the method, use the database access you already have to fill your email. You should not depend of information received by the front (like Angular), because it's easily manipulable. Use the information you know, the information stored in the database. In this example the tasks starts a 10:00 hours:
#Configuration
#EnableScheduling
public class EmailScheduler {
#Autowired
private PaymentRepository paymentRepository;
#Scheduled(cron = "0 0 10 * * ?")
public void sendEmails() {
JavaMailSenderImpl jms = (JavaMailSenderImpl) sender;
MimeMessage message = jms.createMimeMessage();
MimeMessageHelper helper = new MimeMessageHelper(message, MimeMessageHelper.MULTIPART_MODE_MIXED_RELATED, StandardCharsets.UTF_8.name());
// Here you are accessing the payments close to the deadline
List<Payment> payments = paymentRepository.findPaymentsCloseToDeadline();
/* Send an email for each payment. Use the database info you already have to fill the information */
for (Payment payment : payments) {
try {
helper.setFrom("smsender4#gmail.com");
// Fill the recipients with the info you need
String[] recipients = {payment.getUserEmail(), "other#email.com"};
helper.setTo(recipients);
String msg = "Here would go the message";
helper.setText(msg, true);
helper.setSubject("Test Mail");
sender.send(message);
// You would still need to calculate the ID and the days if you require them
enr.save(new EmailNotification(id, "Test mail", msg, days,
recipients, "today's date in LocalDate"));
} catch (MessagingException e) {
throw new RuntimeException("fail to send emails: " + e.getMessage());
}
}
}
}
This is only a guideline because there's still some things I don't know about your code, but I hope it's clear enough so it helps you. Good luck.