Cloudflare Developers•2mo ago

Stream it back via WebSockets

11984 Ford Laser Stream it back via WebSockets

Larry•11/6/25, 12:34 AM

Would need something like that. I'm sure someone has already built that or will soon.

mau•11/6/25, 2:50 AM

Request/Question:

I was wondering if there’s a way to perform a cross join between data stored in different Durable Object tables — similar to how PostgreSQL uses foreign data wrappers (FDWs). It would be game changer.

Mmau Request/Question: I was wondering if there’s a way to perform a cross join betw...

Larry•11/6/25, 3:41 AM

That would be a neat trick, but I've never heard of anything like that, and I probably would have if it existed.

LLarry Would need something like that. I'm sure someone has already built that or will ...

ALECKS•11/6/25, 4:13 AM

It's built in, you can open a ws to anything insider your sandbox
https://developers.cloudflare.com/sandbox/guides/websocket-connections/

AALECKS It's built in, you can open a ws to anything insider your sandbox https://devel...

Larry•11/6/25, 4:19 AM

It's good to know that the WebSocket part is already built in. Do you know anyone who is using it as a remote AI coding platform? I'd love to hear more about the setup.

ALECKS•11/6/25, 4:21 AM

No I just recently found out about this myself. Looks like a killer offering tho... docker container, with DO-like ergonomics

ALECKS•11/6/25, 4:29 AM

Does anyone happen to know, if you call a DurableObject via RPC, does that implicitly also wake up its associated Worker?

To ask differently. Do I get billed more if I do:
CallerA -> WorkerB.rpc() -> DO-B.rpc()
vs
CallerA -> DO-B.rpc()

AALECKS Does anyone happen to know, if you call a DurableObject via RPC, does that impli...

Larry•11/6/25, 5:08 AM

What is CallerA? Is it client-side (browser or app)? Workers RPC is between Workers, DOs, and RpcTargets. If you want all the way to the client, you need something like Cap'n Web or Lumenize RPC. If you are just using Workers RPC, the called DO is accessed directly without the involvement of the Worker in the module where that DO is defined.

Kunal Verma•11/6/25, 7:31 AM

how can I view storage.kv/_cf_KV items for remote durable objects?

scruffy•11/6/25, 10:35 AM

Hihi! If I spin up a Durable Object to store session data via the KV API and give the data an expiry via TTL, will the Durable Object still exist after the data's expired? If so, is there any residual wrapper that might incur storage costs?

Sscruffy Hihi! If I spin up a Durable Object to store session data via the KV API and giv...

Larry•11/6/25, 12:19 PM

Workers KV has expiration dates but the KV inside a DO does not. You'd have to implement that yourself, or use Workers KV.

KKunal Verma how can I view storage.kv/_cf_KV items for remote durable objects?

Larry•11/6/25, 12:30 PM

You can add a method on the remote DO that returns it and then call that method remotely using Workers RPC. So,

this.env.REMOTE_DO.getByName('remote-instance-name').get_cf_KV()

this.env.REMOTE_DO.getByName('remote-instance-name').get_cf_KV()

. If you are going to call the remote DO more times, I recommend that you two-step it and put the the remote DO stub in a variable. So:

const remoteStub = this.env.REMOTE_DO.getByName('remote-instance-name');
const remote_cf_KV = remoteStub.get_cf_KV();

const remoteStub = this.env.REMOTE_DO.getByName('remote-instance-name');
const remote_cf_KV = remoteStub.get_cf_KV();

if you are using id's instead of instance names its:

const remoteId = this.env.REMOTE_DO.getIdFromString('23abc...');  // 64 byte opaque hex
const remoteStub = this.env.REMOTE_DO.get(remoteId);
const remote_cf_KV = remoteStub.get_cf_KV();

const remoteId = this.env.REMOTE_DO.getIdFromString('23abc...');  // 64 byte opaque hex
const remoteStub = this.env.REMOTE_DO.get(remoteId);
const remote_cf_KV = remoteStub.get_cf_KV();

The only tricky part most of the time is knowing the id or name of the remote DO.

LLarry Workers KV has expiration dates but the KV inside a DO does not. You'd have to i...

scruffy•11/6/25, 12:56 PM

thanks for the info. in terms of how to implement in DO, is this only doable via alarms or are there other alternatives?

Bboop If you generate and query by name, you have to supply the jurisdiction. If you u...

1534980751438970153470891543•11/6/25, 6:04 PM

that wouldve saved me a lot of work lol....

1534980751438970153470891543•11/6/25, 6:06 PM

at least it looks consistent... i added jurisdiction even when using the DO IDs

WWallslide When I'm running a worker locally, how can I clear out my local durable objects

Hard@Work•11/6/25, 11:55 PM

You can nuke the

.wrangler

.wrangler

directory, or find the specific DO namespace folder and delete it

Tuna•11/7/25, 7:00 AM

HI everyone,

is it possible to mix a durableObject to have Sqllite and also key value?
i have some structured data that i want to save and avoid recalculating, the issue that if i use tabular structure its take for ever to save to sqlite, and if i use a json its failing cause this json is too big.
what is the best practice here?

Ffaraday sql durable objects have synced kv storage

Larry•11/7/25, 12:03 PM

As of 2025-09-12 compatiblity date you can do

const x = this.ctx.storage.kv.get(”x”);  // no await

const x = this.ctx.storage.kv.get(”x”);  // no await

HHard@Work Not natively, though you should be able to dump the SQL manually

Jaiganesh•11/7/25, 1:25 PM

Hi, I was also wondering the same thing...
I am not a developer but an infra guy ... could you please let me know how to dump SQLlite manually?

JJaiganesh Hi, I was also wondering the same thing... I am not a developer but an infra guy...

Larry•11/7/25, 3:27 PM

Export ~~for backup~~ is a real hole in Cloudflare's offering at this time. I keep saying, "You have read replicas working. Please, just disconnect one and stick the .sqlite file in R2." The response I keep getting is that idea is just one option that's part of a larger discussion. What I haven't heard is that I'm wrong and it's not as easy as I think, but I do wonder if that's true.

LLarry Export ~~for backup~~ is a real hole in Cloudflare's offering at this time. I ke...

lambrospetrou•11/7/25, 3:37 PM

What I haven't heard is that I'm wrong and it's not as easy as I think, but I do wonder if that's true.

I said this multiple times

Right now, you cannot just go and "disconnect one and stick the .sqlite file in R2". It can be done, and that's our plan in some form, but it's not a 2 hour thing our next intern can do.

And to add more colour, it's not that it takes 8 months to do this, it's just that other priorities postponed this work.

Llambrospetrou > What I haven't heard is that I'm wrong and it's not as easy as I think, but I ...

lambrospetrou•11/7/25, 3:40 PM

Exporting, backups, migration to some other database system, are all on the roadmap. You can argue they should be higher priority than what is delivered, which is fair, but we can say that for all the other 100 features users are asking for.

Llambrospetrou Exporting, backups, migration to some other database system, are all on the road...

Larry•11/7/25, 3:58 PM

When I've been in product manager roles in the past, whenever some annoying person (like I am right now) tells me something should be easy, my reply is, "Not as easy as you think, but if you tell me which of these 10 other things that are near the top of the backlog you would like this to take priority over, we will put it in that spot. Think about it overnight and we'll adjust when you come back in the morning." They usually look at the list and tell me that they think the priorities are pretty close to right as-is. I'm sure that's the case now also.

Burrito•11/7/25, 4:22 PM

Not just for backup, real data is also useful for debugging. It's not always simple to manually reproduce a complex database locally.

jjjrmy•11/7/25, 4:35 PM

with a Durable Object - is it possible to get the name you used

idFromName

idFromName

from within the DO?

jjjrmy•11/7/25, 4:36 PM

in my log I'm seeing:

ctx: DurableObjectState { ...,
  id: DurableObjectId { name: undefined }
}

ctx: DurableObjectState { ...,
  id: DurableObjectId { name: undefined }
}

Jjjjrmy with a Durable Object - is it possible to get the name you used `idFromName` fro...

Larry•11/7/25, 4:43 PM

It is not unless you pass it in somehow. Many people have an init() method that they call at the right moment(s) that sticks it in storage. I put the name in a header that my fetch handler plucks out of the header and populates. That only works for me because I never create new instances via Workers RPC. My instances are always created with an HTTP call (either a real fetch/Request or the WebSocket upgrade request).

jjjrmy•11/7/25, 4:53 PM

I'm basically using all RPC calls I think

jjjrmy•11/7/25, 4:53 PM

so why does it have the

{ name : undefined }

{ name : undefined }

jjjrmy•11/7/25, 4:53 PM

like not that I set it as undefined, what's even the point of it being there

Jjjjrmy like not that I set it as undefined, what's even the point of it being there

lambrospetrou•11/7/25, 4:55 PM

The type is for

DurableObjectId

DurableObjectId

, which is used both on the caller side of the RPC and inside the DO. In the caller side the

.name

.name

will be populated correctly. The fact it's not populated inside the DO is a long-term known bug.

Llambrospetrou The type is for `DurableObjectId`, which is used both on the caller side of the ...

jjjrmy•11/7/25, 4:59 PM

so is there a case when it should show?

Jjjjrmy so is there a case when it should show?

lambrospetrou•11/7/25, 5:00 PM

Inside the DO, it will never show right now, until the bug is fixed internally.

jjjrmy•11/7/25, 5:00 PM

basically for example I have 2 DOs, each with some data in KV.
I can call

firstDO.index()

firstDO.index()

and

secondDO.index()

secondDO.index()

to get the list of the items. but I want to include the name of the DO in the list. Ideally it could be done within the

index()

index()

function and not after.

Jjjjrmy basically for example I have 2 DOs, each with some data in KV. I can call `first...

lambrospetrou•11/7/25, 5:03 PM

As Larry said, at the moment the workaround is to store the name inside the DO storage during the DO initialization phase if you have one, otherwise in any of the followup calls, or you pass it all the time as argument. What you do and how depends on your use-case. Cumbersome, but unfortunately these are the options to have it in there.

jjjrmy•11/7/25, 5:05 PM

so anyone trying to fix this well known long-term bug?

jjjrmy•11/7/25, 5:06 PM

basically my point is if you have to pass it in to the DO - I might as well just include the data outside of the DO since that's where it's coming from anyways.

Jjjjrmy so anyone trying to fix this well known long-term bug?

lambrospetrou•11/7/25, 5:11 PM

You can track this bug in https://github.com/cloudflare/workerd/issues/2240

Llambrospetrou The type is for `DurableObjectId`, which is used both on the caller side of the ...

João Castro•11/7/25, 5:32 PM

Since it is never populated inside the DO (and I suppose this won't be fixed short-term), I think it would be better and cause less confusion to have different type definitions for each place, where the one in the DO instance wouldn't have the

.name

.name

property

Need_Not•11/7/25, 6:02 PM

Trying to move a KV DO to SQLite and I know I'll have to delete it and create a new one. But how do you do that? what does the migration look like? Do I have to completely remove the binding from wrangler, build then readd it?

Need_Not•11/7/25, 6:04 PM

do i simply do this?

        {
          "tag": "v3",
          "deleted_classes": [
            "UserCreditsObject"
          ],
          "new_sqlite_classes": [
            "UserCreditsObject"
          ]
        }

        {
          "tag": "v3",
          "deleted_classes": [
            "UserCreditsObject"
          ],
          "new_sqlite_classes": [
            "UserCreditsObject"
          ]
        }

ldenoue•11/7/25, 6:39 PM

Just got issues with SQLite today in my DO where I stored user tables. "Error: Exceeded allowed rows written in Durable Objects free tier". Which is really strange since I'm only storing a few rows (8 users!) and 100 rows in a table called "transcripts".

jjjrmy•11/7/25, 6:51 PM

So they just call

setIdentifier

setIdentifier

every time they "get" an Actor instance (which is a Durable Object) and refer to

this.identifier

this.identifier

rather than try to parse the name out of the id. It's very little code and works the same in dev and production.

Jjjjrmy So they just call `setIdentifier` every time they "get" an Actor instance (which...

lambrospetrou•11/7/25, 6:55 PM

Personally, I suggest against this for what's worth. Doing explicitly as it suits your use-case, either once at the beginning/creation, or in every request.

Jjjjrmy So they just call `setIdentifier` every time they "get" an Actor instance (which...

Larry•11/7/25, 8:00 PM

I'm basically using all RPC calls I think

I hear people say this and I always wonder how users enter the system? It's got to be HTTP or WebSockets, no?