@vercel/kv Inconsistent increment behavior in Server Action about storage

[luismeyer]

I forked your repo and tried without the revalidation time and a revalidatePath call inside the form action. It seems to work now (or are you expecting different results?). Note that when you refresh the page you might see old numbers because the ISR is revalidating the full router cache in the background. I guess that could be avoided with dynamic=force-dynamic but than you loose the benefit of a fast cached response.

Commit: luismeyer/rappelscanner@1c30b1c
Preview: https://rappelscanner-git-feat-kv-luimey.vercel.app/?vercelToolbarCode=QCiZmInmjrleAx6

[thomaslenaour]

hey @thomaslenaour, could you give some more context on from where you are calling the server action?

I just tried this based on the kv-redis-starter-example and it works just fine: https://kv-redis-starter-lime-rho.vercel.app. I did not set revalidate=60 to opt into ISR though.

Hey @luismeyer, thanks for your response. In fact, here's the implementation I'm working on for a mini project: https://github.com/thomaslenaour/rappelscanner/blob/56402b2571c133f1aa89b708943c12da6ff344e3/app/_actions/product.ts#L52. Indeed, I've already tried playing with the Vercel example and the counter, and it works perfectly.

I feel like I've implemented it correctly, based on the example you mentioned, but I think I might be missing something because I can't get it to work in my project.

The Server Action is called upon form submission, as soon as you click on a "Search" submit button.

• Preview link: https://rappelscanner-git-feat-kv-thomaslenaour.vercel.app
• Repository link on the feat/kv branch: https://github.com/thomaslenaour/rappelscanner/tree/feat/kv

[luismeyer]

hey @thomaslenaour,
could you give some more context on from where you are calling the server action?

I just tried this based on the kv-redis-starter-example and it works just fine: https://kv-redis-starter-lime-rho.vercel.app. I did not set revalidate=60 to opt into ISR though.

[thomaslenaour]

Incredible! It seems to be working now. I was convinced that I had already tried it with revalidatePath, but it still wasn't working.

Now, it works fine locally (with dockerized Redis) and also works in the Preview environment.

Thank you for your time and for your assistance @luismeyer!

That being said, in an attempt to understand things a bit better: why didn't the change of value occur in my initial code? Apparently, we just added revalidatePath and removed the revalidation time. But that shouldn't have an impact on the incrementation of the scans value, right?

[luismeyer]

Glad I could help :)

I think beforehand you were running into the data cache. @vercel/kv is doing fetch requests to the upstash API and as stated in the the docs all fetch requests are cached by default. revalidatePath is purging the data cache and therefor when you call the action again the increment really happens.

I didn't try it but I think you could even keep the revalidate=60 in you page segment config.