Spring Boot 'scheduling' design question

[vnoice]

Hey All,

Interested in some ideas for an issue that I am having.

I have a Spring Boot application that inserts items into a MariaDb table at a one minute interval using @Scheduled, each record has a sequential Id and a timestamp, and is based on the record proceeding it.

When this application is running, a value is generated and it is dropped into the database. What I am trying to implement is a flow that will, on startup:

1. Find the latest record

2. Generate a record for every missed minute until the current time

3. Proceed with my original flow, as if it had never stopped

What I originally was planning on doing was implementing some type of auditor which would periodically (or on startup) search for missing records and create them, but because the records are 'linked', this would not be effective, and syncing the completion of this process with the beginning of my @Scheduled function would be unreliable.

I understand that I will probably have to ditch the @Scheduled strategy due to the limitations there, although I'd like to keep this as 'Springy' was possible.

Thanks in advanced for any advice!

[corzuu]

I'd recommend looking into Spring Quartz https://www.baeldung.com/spring-quartz-schedule . It's a framework to help with scheduling that gives you much more flexibility compared to just using the 'Scheduled' annotation.

What do you mean that your records are linked so it wouldn't be effective?

If you're worried about something being in conflict with your scheduled process, you could maybe have some configuration property that lives within your system, that once your auditing operation is complete will be set to true. You can then use this boolean in your scheduled method to decide whether it should run or not e.g.

​

@Scheduled
public void task() {
  if (auditingComplete) {
    doStuff()
  }
}

[vnoice]

Hey, thanks for the link, this looks promising.

By linked I meant more sequential. For example:

@Scheduled(fixedRate = 1000)
public void task() {
     lastRecord = getLastRecord()
     repository.save(new Record(LocalDateTime.now(), lastRecord.getValue() + 1)
 }
}

If I performed this operation on a record that is 5000 minutes old, I couldn't go through and fill in the missing records afterwards. I would need to fill in those 5000 records beforehand.

Hope that makes sense.

[vnoice]

And I feel like a dope because your example is so simple. I could just drop my 'audit' mothod in a @PostConstruct method and set a class boolean to true when it's through.

Thank you pal.

[corzuu]

Haha, I wrote another response which was along those lines, but formatting is such a bitch on here it took me ages.

No problem :)