Package io.meeds.commons.digest.service

Class DigestOccurrenceProcessor

java.lang.Object

io.meeds.commons.digest.service.DigestOccurrenceProcessor

@Component
public class DigestOccurrenceProcessor
extends Object

One occurrence of one frequency for one user, as a single transaction: the claim of the occurrence (the guarded move of the watermark), the reading of the waiting items, the building of the email, its row in the mail queue and the deletion of the covered items commit together, or roll back together. A crash in the middle leaves the watermark where it was, and the user is simply served again at the next run: an item is late, never lost, and never sent twice.

Constructor Summary

Constructors

Constructor	Description
DigestOccurrenceProcessor(DigestSettingStorage settingStorage, DigestScheduleStorage scheduleStorage, DigestMailBuilder mailBuilder, DigestMailQueueStorage mailQueueStorage)

Method Summary

Modifier and Type	Method	Description
boolean	serve(DigestUserEntity user, io.meeds.commons.digest.model.DigestFrequency frequency, Instant now)	Serves one occurrence.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

DigestOccurrenceProcessor

public DigestOccurrenceProcessor(DigestSettingStorage settingStorage,
 DigestScheduleStorage scheduleStorage,
 DigestMailBuilder mailBuilder,
 DigestMailQueueStorage mailQueueStorage)

Method Details

serve

@Transactional(rollbackFor=java.lang.Exception.class)
public boolean serve(DigestUserEntity user,
 io.meeds.commons.digest.model.DigestFrequency frequency,
 Instant now)

Serves one occurrence. Any exception rolls the whole occurrence back, claim included, and reaches the caller.

Parameters:

user - the work list row, as read when the candidates were selected

frequency - the frequency due

now - the new watermark, the moment of the run

Returns:

true when this worker got the occurrence (whether or not an email went out), false when another worker took it first