This message was deleted.
# questionss
Slackbot
11/28/2023, 8:11 AMThis message was deleted.
k
kofhearts
11/29/2023, 4:59 AMthank you mattias. ill give it a try.
kofhearts
11/30/2023, 4:59 AM@mattias_reichel thank you mattias. Today i checked the logs and there werent optimistic locking failure. can you please help me understand how this prevented the optimistic locking failure. how does putting
Copy code
PageHitCounter.findOrCreateByPageIdentifier(pageIdentifier)m
mattias_reichel
11/30/2023, 6:02 AMIf you're not performing both the read and update operations within the same transaction, there's a risk that another thread could modify the database row between the moment you read the value and when you attempt to update it.
k
kofhearts
11/30/2023, 7:41 AM@mattias_reichel thank you very much! ill wait one more day. if there is no error in the log tomorrow ill accept the answer. thanks for the help!
kofhearts
12/01/2023, 4:56 AM@mattias_reichel hi mattias thanks for the response but looks like this approach didnt work. today i saw couple of optimistic locking failure exceptions in the logs. the exceptions are of the same nature as posted in the original post. https://stackoverflow.com/questions/77561762/how-to-create-a-thread-safe-hit-counter-in-grails could you suggest another approach? Thanks!
m
mattias_reichel
12/01/2023, 11:12 AM@kofhearts I have updated the answer 👍.
k
kofhearts
12/03/2023, 5:46 AMthanks mattias. what do you think of this approach?
i have moved the hit counter update logic to hitcounterservice.
Copy code
@Transactional
class HitCounterService {
def synchronized visit(pageIdentifier) {
def hitCounter = null
hitCounter = PageHitCounter.findOrCreateByPageIdentifier(pageIdentifier)
hitCounter.hits = hitCounter.hits + 1
hitCounter.save()
return hitCounter?.hits
}
}def verifyRegistration(Long id){if(springSecurityService.isLoggedIn()){redirect(controller: "user", action: "index")return}[id: id, hits: hitCounterService.visit("${controllerName}/${actionName}/${id}")]}kofhearts
12/03/2023, 5:47 AMwould making the visit method in the service synchronized do the trick?
m
mattias_reichel
12/03/2023, 4:32 PMYes, that should work. But then you are synchronizing updates to all page identifier even though you only need to prevent updates to the same page identifier (database row) by different threads. That is why I used the a map to store different objects to synchronize on. Maybe that is a premature optimization on my part.
k
kofhearts
12/07/2023, 7:07 AM@mattias_reichel thank you very much!
👍 1