I have been trying to send notifications to my customers once. I'm using kubernetes and I create multiple spring boot applications because I have 2 replicas. This is all fine but when the scheduler runs, each one of them can send notifications. I have looked a little bit at quartz but the config seems to be a little complicated. Is there an easy way to do so?
@Scheduled(fixedDelayString = "300000")
public void sendFlowerNotification() {
//Code
}
You can also use dlock to execute a scheduled task only once over multiple nodes. You can simply do something like below.
@Scheduled(fixedDelayString = "300000")
@TryLock(name = "flowerNotification", owner = POD_NAME, lockFor = THREE_MINUTES)
public void sendFlowerNotifications() {
List<Notification> notifications = notificationService.getNotifications();
for(Notification notification: notifications){
sendNotification(notification);
}
}
You can send the POD_NAME to spring as an environment variable. dlock would automatically handle it.
env:
- name: POD_NAME
valueFrom:
fieldRef:
fieldPath: metadata.name
See the article about using it.