https://developers.cloudflare.com/durable-objects/#_top
Cloudflare Docs
Durable Objects provide a powerful API for coordinating multiple clients or users, each with private, transactional and strongly consistent storage attached.
EAh okay, so this is available through the transactional storage api?
HOr well, each DO has a separate KV Store
EThanks, I'll take a proper read through it.
TThis seems like an optimization for an extremely unlikely use case. How many keys do you plan on storing and is it anywhere near risking hash collision?
You could also reduce probably by making a read first, and writing it if it doesn't exist. It won't deterministically guarantee that you aren't overwriting, because it may have been written/propagated to KV since the read, but it wouldn't hurt in reducing chances of collision
If you need stronger unique guarantees, DO/D1 may be better options
You could also reduce probably by making a read first, and writing it if it doesn't exist. It won't deterministically guarantee that you aren't overwriting, because it may have been written/propagated to KV since the read, but it wouldn't hurt in reducing chances of collision
If you need stronger unique guarantees, DO/D1 may be better options
EMy plan is to reuse this authentication and session system whenever I can when making Sveltekit projects so I wanted to make something robust enough to handle a large number of users authenticating themselves frequently. I've considered reading before the writing but as you mentioned it only reduces the chances on top of an extra network call. D1 was the only real solution for me before learning about DO.
EAs for the use cases. I probably may never generate enough magic tokens to increase the odds of a duplication within a period of time as the size of the tokens is 64 chars generated by the crypto module. I think I just wanted a solution to a hypothetical problem.:NotLikeThis:
HMake a separate KV for every project and you should be fine
HIf you really want to avoid collision at all cost, then you can append a unix timestamp to the token
HIf you manage to generate two identical 64 char tokens within a single second you would probably be the luckiest human to have ever existed. Heck, even getting a single collision at all would make you the luckiest person of all time
HYou could also generate a UUID7 which has a granularity of up to 50 nanoseconds 
TYou should probably store your information in D1, then optimize with KV (ie once a user logs in, check hash against db hashed, but then store tokens in kv and use that for auth validation)
AWhy key-value data storage is so expensive comparing to other resources?
KV read price - $0.50/million
Durable objects (that sounds a lot more complex, "permanent" and expensive) - $0.15/million
D1 database - $0.001 / million rows reads
Why everything else, where I can store some data is cheaper? Isn't kv - a cheap, temporary, cache storage?
KV read price - $0.50/million
Durable objects (that sounds a lot more complex, "permanent" and expensive) - $0.15/million
D1 database - $0.001 / million rows reads
Why everything else, where I can store some data is cheaper? Isn't kv - a cheap, temporary, cache storage?
MCloudflare Docs
Workers KV is a data storage that allows you to store and retrieve data globally. With Workers KV, you can build dynamic and performant APIs and websites that support high read volumes with low latency.
TAnd to add on to Matt's response, each key-value pair in KV can handle a much higher throughput than individual rows in D1
AHmm, ok. Is KV the best tool to store and read some cache data? Like I have a complex worker function. During its work, I have to hit several 3rd party API. And I don't want to call them on every worker execution. I want to temporary cache data. On regular server I would use redis or a simple in-memory cache. What about worker? What should I use here? KV?
TYes, KV is the tool for this. there's cache api https://developers.cloudflare.com/workers/runtime-apis/cache/ but that is definitely an optimization and might get evicted from cache
JDefinitely something you can do, I use KV to store Tailwind off the CDN (for funsies), I try weird uses of Cloudflare products in this project all the time just to see if I can and if there is other novel things you can do https://github.com/JacobMGEvans/JacobMGEvans/blob/main/src/index.ts
JAdditionally you can use the Worker Cron to run occasionally and purge anything thats older than a certain age you give them, since you mentioned temporary 
AI think KV is good for storing permission level data on top of D1. Like checking for permissions of a user on each api call before accessing D1 or other db.
TStill receiving the message "Daily request limit exceeded for Cloudflare Workers" for a "1000 put operations" which is in fact of 226 right now!
More than a week has passed, shouldn't we have more information?
More than a week has passed, shouldn't we have more information?
BHello every one ! Have anyone know how to rename the KV Namespace?
BI remember that it could be renamed in the past but now it seems not to work anymore
TThanks for bringing it up again. This is our top priority fix at the moment. A query that is being made to alert on free quotas is misreporting quotas, so we’re fixing that. I will keep this message thread updated. Note that the query resets every day so you may not encounter this all the time
TThat's interesting, how do you check the current age of a KV key? I would like to set a high cacheTtl for a key while also being able to show a 'refresh' button if the current value is cached but also 3 days old for example
TI somehow understand it needs time to fix it, but shouldn't WE have a test period for this kind of things?
JI'd have to look at how I've done it before but my knee jerk (from my phone) reaction without looking is probably timestamp in the Metadata, maybe something like this
TAhh, sure! Thank you! That will do it
MIn case you missed it — here's the details on the latest Workers KV performance improvements that just shipped! https://blog.cloudflare.com/faster-workers-kv/ @Workers KV
The Cloudflare Blog
Today, we’re announcing up to 3x faster KV hot reads, with all KV operations faster by up to 20ms. And we want to pull back the curtain and show you how we did it.
AWow!
Thats a massive gain!
Thats a massive gain!
Dthat's huge! very nice!
DThank you!
TWe're super excited for this ship, and we're going to continue to make KV super fast for your data globally. The details of how we did it are all in the blog, but the graphs really show the impact 
BIn the kv docs /getting-started
I can't get this command to work:
npx wrangler kv key put --binding=<BINDING_NAME> "<KEY>" "<VALUE>"
just trying to follow the kv-tutorial
I used kv_binding_name - trying to follow the docs.
Though the docs say: name it BINDING_NAME - the very next step shows a create command with kv_binding_name
✘ [ERROR] A namespace with binding name "kv_binding_name" was not found in the configured "kv_namespaces".
✘ [ERROR] A namespace with binding name "kv-tutorial-kv_binding_name" was not found in the configured "kv_namespaces".
I can't get this command to work:
npx wrangler kv key put --binding=<BINDING_NAME> "<KEY>" "<VALUE>"
just trying to follow the kv-tutorial
I used kv_binding_name - trying to follow the docs.
Though the docs say: name it BINDING_NAME - the very next step shows a create command with kv_binding_name
✘ [ERROR] A namespace with binding name "kv_binding_name" was not found in the configured "kv_namespaces".
✘ [ERROR] A namespace with binding name "kv-tutorial-kv_binding_name" was not found in the configured "kv_namespaces".
BIt does work with the ID - but, I'm just reporting broken documentation continuity.
Jhelp I am trying to import kv to my javascript worker with
import { KVNameSpace } from '@cloudflare/kv-name-space'
Tit doesn;t work@JamieD132 What is the error you're getting and what do you expect to get?
T
KHi guys! The documentation is a little murky on this one, how do I specify the expiration on the KV PUT REST body? https://developers.cloudflare.com/api/operations/workers-kv-namespace-write-key-value-pair-with-metadata
Interact with Cloudflare's products and services via the Cloudflare API
MOoh yeah they should have an example body there, for sure. I assume it's the same as the
wrangler kv bulk putwas that a suggestion from an AI tool? that's my best guess :D anyway, follow https://developers.cloudflare.com/kv/get-started/#3-bind-your-worker-to-your-kv-namespace and https://developers.cloudflare.com/kv/get-started/#5-access-your-kv-namespace-from-your-worker to use a KV namespace with a worker
TThanks for flagging! let me verify
T@kindaraffy yes, expiration is supported in the REST API, we'll be fix that in docs
You can specify expiration or expirationTtl as a query param
So I can tell the users: https://api.cloudflare.com/client/v4
/accounts/{account_id}/storage/kv/namespaces/{namespace_id}/values/{key_name}?expiration=<secondsSinceEpoch>
or https://api.cloudflare.com/client/v4
/accounts/{account_id}/storage/kv/namespaces/{namespace_id}/values/{key_name}?expirationTtl=<secondsFromNow>
You can specify expiration or expirationTtl as a query param
So I can tell the users: https://api.cloudflare.com/client/v4
/accounts/{account_id}/storage/kv/namespaces/{namespace_id}/values/{key_name}?expiration=<secondsSinceEpoch>
or https://api.cloudflare.com/client/v4
/accounts/{account_id}/storage/kv/namespaces/{namespace_id}/values/{key_name}?expirationTtl=<secondsFromNow>
KThank you.
CHey! Are there documented (or undocumented) rate limits on number of writes to different KV keys from a worker (on the paid plan)? We are seeing 429s when we try to write a few thousand keys within a few seconds.
TKV has 1 write per second per key limit from the binding https://developers.cloudflare.com/kv/platform/limits/ and the APIs have global rate limits https://developers.cloudflare.com/fundamentals/api/reference/limits/#:~:text=The%20global%20rate%20limit%20for,receiving%20a%20HTTP%20429%20response.
CDo the api rate limits apply to calls made from a worker binding?
CWe are writing to different keys, so the 1 per second should not apply
TDM'd
IRelated to the new upcoming cache purging changes, couldn't these also apply to KV?
https://blog.cloudflare.com/instant-purge/
Is it generally possible to purge a specific KV key? I think if a KV value is locally cached, and you update this it could in theory especially with the new purging system 'instantly' purge all regional KV caches right? Think this could bring quite some benefits to keep KV reads latency.
E.g. I need super quick access to a 'configuration' stored in KV, this 'configuration' is updated at most a couple of times a day. If we can keep this in the cache until this value is updated or deleted, it would speed up calls to KV a lot. Currently it's documented that KV updates do not purge KV caches, in this case it would be great if it did!
https://blog.cloudflare.com/instant-purge/
Is it generally possible to purge a specific KV key? I think if a KV value is locally cached, and you update this it could in theory especially with the new purging system 'instantly' purge all regional KV caches right? Think this could bring quite some benefits to keep KV reads latency.
E.g. I need super quick access to a 'configuration' stored in KV, this 'configuration' is updated at most a couple of times a day. If we can keep this in the cache until this value is updated or deleted, it would speed up calls to KV a lot. Currently it's documented that KV updates do not purge KV caches, in this case it would be great if it did!
TThanks for the feedback @ItsWendell, like you mentioned, KV doesn't have cache purges but it's something we're keeping our eyes on