hello all! In all examples I see alarms being scheduled for several seconds in the future. If I want

hello all! In all examples I see alarms being scheduled for several seconds in the future. If I wanted to schedule immediate async work (i.e.

await this.ctx.storage.setAlarm(Date.now());

await this.ctx.storage.setAlarm(Date.now());

) could I run into any issues? Are there any gotchas here? I have been using this and it works, however, I have encountered (what seems to be) race conditions with this async work so I wonder if that immediate alarm has anything to do with this.

WWonderPandaDev Hey I've been trying to get this to work for a while now. I have two different w...

James•1/6/25, 4:35 PM

for local dev, route DO requests to the DO fetch worker instead of the direct binding since multiple DO bindings local doesn't really work

FFernando Barroso hello all! In all examples I see alarms being scheduled for several seconds in t...

James•1/6/25, 4:40 PM

maybe, since the whole DO is single threaded, you could run into scaling issues with that vs using a queue and worker instead, also DO CPU is more expensive than a worker

danjenkins•1/6/25, 11:20 PM

I swear there used to be a way to assign metadata to a websocket in durable objects and then find all the websockets that had that meta data? I can't find any docs on it now?

danjenkins•1/6/25, 11:22 PM

ah just like that found it

JJames for local dev, route DO requests to the DO fetch worker instead of the direct bi...

WonderPandaDev•1/7/25, 3:37 AM

Hey thanks for the tip I'll try this out! Is this documented anywhere? Still trying to ramp up on the expected experience when developing locally. Just to make sure I understand, are you saying I should keep the service binding and use that to forward the Request to the worker running in a separate wrangler dev process and then that can pass the request to the DO?

James•1/7/25, 4:18 AM

I made a proxy obj in front of the binding in my main app. If I’m running local, the proxy sends a fetch to localhost separate wrangler running the DO with the same payload and response signature. If not local, the proxy just calls the binding directly.

The fetch handler on the DO only runs locally, and instantiates the stub directly based on the request body.

Ddanjenkins I swear there used to be a way to assign metadata to a websocket in durable obje...

1984 Ford Laser•1/7/25, 6:56 AM

for anyone looking for this in the future, you do

this.state.acceptWebSocket(socket, topic)

this.state.acceptWebSocket(socket, topic)

, then to find connections by

topic

topic

you would do

this.state.getWebSockets(topic)

this.state.getWebSockets(topic)

11984 Ford Laser for anyone looking for this in the future, you do `this.state.acceptWebSocket(so...

danjenkins•1/7/25, 1:04 PM

my bad, in my haste I forgot to mention how its done!

BBrayden Here's a further example in action to help demonstrate as well: ``` public exec...

Larry•1/7/25, 1:59 PM

Thanks for giving that example. It's perfect for when you have an array of SQL statements you want to execute in a transaction. You can also take advantage of my favorite thing about the DO concurrency model by intermixing queries and code using

this.storage.transactionSync(() => {...})

this.storage.transactionSync(() => {...})

directly. In the callback, you can do a query, process it with code, do another query, etc. Then, every storage operation in that callback will either all-succeed or all-fail.

Vitor S•1/7/25, 3:56 PM

Someone can help me?

Vitor S•1/7/25, 3:56 PM

https://stackoverflow.com/questions/79336461/trying-to-use-websocket-hibernation-api

Stack Overflow

Trying to use Websocket Hibernation Api

I have a Cloudflare Worker that uses Durable Objects and WebSocket. However, the costs of WebSocket are high, so I decided to implement the Websocket Hibernation API (https://developers.cloudflare....

Vitor S•1/7/25, 3:57 PM

I tried to migrate from the standard websocket api to hibernation but I can't.

Vitor S•1/7/25, 3:57 PM

I changed the listeners to webSocketMessage() and webSocketClose(), theoretically that's all I need to change, right?

Ephemeros•1/7/25, 6:24 PM

what's the recommended way to keep a durable object staying up forever? e.g. to listen to the bsky firehose

and restart if it crashes somehow

or, should I use something other than a DO for that?

Ephemeros•1/7/25, 6:26 PM

hmm, maybe with repeated alarms to keep it awake?

Original message was deleted

Ephemeros•1/7/25, 7:26 PM

thanks for confirming!

VVitor S I changed the listeners to webSocketMessage() and webSocketClose(), theoreticall...

1984 Ford Laser•1/7/25, 9:11 PM

how are you accepting the connection? You need to use

this.state.acceptWebSocket(socket)

this.state.acceptWebSocket(socket)

11984 Ford Laser how are you accepting the connection? You need to use `this.state.acceptWebSocke...

Vitor S•1/8/25, 1:04 PM

Im using the acceptWebsocket()

11984 Ford Laser how are you accepting the connection? You need to use `this.state.acceptWebSocke...

Vitor S•1/8/25, 1:05 PM

async fetch(request) {
    const upgradeHeader = request.headers.get("Upgrade");

    if (upgradeHeader === "websocket") {
      const [client, server] = Object.values(new WebSocketPair());

      this.state.acceptWebSocket(server);

      const isFirst = this.sessions.size === 0;

      server.serializeAttachment({ isFirst });

      this.sessions.set(server, { isFirst });

      if (!isFirst) {
        console.log("sessions.size: ", this.sessions.size);

        // Debug
        for (let [ws, data] of this.sessions.entries()) {
          console.log("WS:", ws, "DATA:", data);
        }

        // find the connection with session.isFirst === true
        const [firstWs, firstSession] = [...this.sessions.entries()].find(([_, session]) => session.isFirst) || [];

        console.log("Found firstWs:", firstWs, "firstSession:", firstSession);

        if (firstWs) {
          console.log("Sending sync.")
          firstWs.send(JSON.stringify({ Evento: "sincronizar_fila", Comando: "" }));
        }
      }

      // When connect, send the stored musics 
      const storedMusics = await this.state.storage.get("musicas");
      if (storedMusics) {
        server.send(JSON.stringify({ Evento: "musicas", Comando: storedMusics }));
      }

      return new Response(null, { status: 101, webSocket: client });
    }

    return new Response("The request is not a websocket.", { status: 400 });
  }

async fetch(request) {
    const upgradeHeader = request.headers.get("Upgrade");

    if (upgradeHeader === "websocket") {
      const [client, server] = Object.values(new WebSocketPair());

      this.state.acceptWebSocket(server);

      const isFirst = this.sessions.size === 0;

      server.serializeAttachment({ isFirst });

      this.sessions.set(server, { isFirst });

      if (!isFirst) {
        console.log("sessions.size: ", this.sessions.size);

        // Debug
        for (let [ws, data] of this.sessions.entries()) {
          console.log("WS:", ws, "DATA:", data);
        }

        // find the connection with session.isFirst === true
        const [firstWs, firstSession] = [...this.sessions.entries()].find(([_, session]) => session.isFirst) || [];

        console.log("Found firstWs:", firstWs, "firstSession:", firstSession);

        if (firstWs) {
          console.log("Sending sync.")
          firstWs.send(JSON.stringify({ Evento: "sincronizar_fila", Comando: "" }));
        }
      }

      // When connect, send the stored musics 
      const storedMusics = await this.state.storage.get("musicas");
      if (storedMusics) {
        server.send(JSON.stringify({ Evento: "musicas", Comando: storedMusics }));
      }

      return new Response(null, { status: 101, webSocket: client });
    }

    return new Response("The request is not a websocket.", { status: 400 });
  }

Vitor S•1/8/25, 1:06 PM

I managed to migrate. But now I have problems with webSocketClose().

I need the connection that has isFirst = true to close all the others when it is closed.

Vitor S•1/8/25, 1:07 PM

what i tried:


async webSocketClose(ws) {
    let session = this.sessions.get(ws);

    this.sessions.delete(ws);

    if (session?.isFirst) {
      console.log("The first. Closing all");
      await this.state.storage.delete("musicas");
      for (let [otherWs] of this.sessions.entries()) {
        otherWs.close();
        this.sessions.delete(otherWs);
      }
    }

    ws.close();
  }


async webSocketClose(ws) {
    let session = this.sessions.get(ws);

    this.sessions.delete(ws);

    if (session?.isFirst) {
      console.log("The first. Closing all");
      await this.state.storage.delete("musicas");
      for (let [otherWs] of this.sessions.entries()) {
        otherWs.close();
        this.sessions.delete(otherWs);
      }
    }

    ws.close();
  }

Vitor S•1/8/25, 1:07 PM

but it is not closing the other connections

peachneo•1/9/25, 1:45 AM

is rpc just sugar over the fetch handler? Or does it have material performance differences (eg uses websockets or some different underlying transpoort)

Ppeachneo is rpc just sugar over the fetch handler? Or does it have material performance d...

Max (@rozenmd)•1/9/25, 11:27 AM

rpc is faster, less overhead

Ppeachneo is rpc just sugar over the fetch handler? Or does it have material performance d...

sathoro•1/9/25, 1:26 PM

websockets are HTTP with more overhead

Ssathoro websockets are HTTP with more overhead 👀

Milan•1/9/25, 3:37 PM

WebSockets start as an HTTP upgrade but once the connection is established it's just TCP.

Milan•1/9/25, 3:38 PM

https://datatracker.ietf.org/doc/html/rfc6455#section-1.7

IETF Datatracker

RFC 6455: The WebSocket Protocol

The WebSocket Protocol enables two-way communication between a client running untrusted code in a controlled environment to a remote host that has opted-in to communications from that code. The security model used for this is the origin-based security model commonly used by web browsers. The protocol consists of an opening handshake followed by ...

Ppeachneo is rpc just sugar over the fetch handler? Or does it have material performance d...

Beefp•1/9/25, 6:12 PM

rpc has limit of i think 1mb arguments/response over the wire

BBeefp rpc has limit of i think 1mb arguments/response over the wire

lambrospetrou•1/9/25, 7:15 PM

You can pass and return streams to overcome the 1mb limit. These streams can even be inside an object.

rob•1/9/25, 7:37 PM

if im looking to do a real time chat with rooms is partyserver the bst bet to get going? Is there any starter examples for that

marko.333•1/9/25, 9:11 PM

I'm a little uncertain of the concurrency rules for Durable Objects RPC calls?
If i have a DO("id1").doStuff() and many concurrent clients are connected to same DO instance ("id1"), then (roughly) all callers to doStuff() are serialized when a storage call is in-progress.
But i wanted to confirm that serialized execution is only triggered for storage calls - correct?
For example, what if the doStuff() implementation included some external calls (to another Worker, or external API fetch, ...)?
While await'ing for the external call to complete, will the other concurrent callers of doStuff() be able to continue execution (ie. an external API call will not cause all other concurrent callers to block)?
Thx.

Mmarko.333 I'm a little uncertain of the concurrency rules for Durable Objects RPC calls? ...

lambrospetrou•1/10/25, 9:49 AM

Yes, if you do an async IO call then other requests will run. If you want to fully block concurrency you can use https://developers.cloudflare.com/durable-objects/api/state/#blockconcurrencywhile

mihaaai•1/10/25, 1:58 PM

When using a sqlite-based Durable Objects, is Libsql for DO storage increasing the cursor memory with each read operation? Asking because we're trying to figure out final costs based also on the Duration GB-s constraint.

Rrob if im looking to do a real time chat with rooms is partyserver the bst bet to ge...

harshil1712•1/10/25, 2:28 PM

Hey, I have used PartyServer and love it because it makes it takes away a lot of boilerplate code. Also, I found this example in the repo: https://github.com/threepointone/partyserver/blob/main/fixtures/chat/README.md
Also, FYI, the repo says it is a Work in Progress

GitHub

partyserver/fixtures/chat/README.md at main · threepointone/partyse...

PartyKit, for Workers. Contribute to threepointone/partyserver development by creating an account on GitHub.

Mmihaaai When using a sqlite-based Durable Objects, is Libsql for DO storage increasing t...

lambrospetrou•1/10/25, 3:17 PM

GB/s is not checking how much memory your code uses, since you are charged for the 128MB allocated to your DO. See details in https://developers.cloudflare.com/durable-objects/platform/pricing/
So, regardless if you use 100MB or 10MB while iterating your results, the billing won't change.

5 Duration billing charges for the 128 MB of memory your Durable Object is allocated, regardless of actual usage. If your account creates many instances of a single Durable Object class, Durable Objects may run in the same isolate on the same physical machine and share the 128 MB of memory. These Durable Objects are still billed as if they are allocated a full 128 MB of memory.

Hharshil1712 Hey, I have used PartyServer and love it because it makes it takes away a lot of...

rob•1/10/25, 3:19 PM

yes thsi! i was looking if someone/s set it up before and could asisst a bit

Rraoulduke Hey I have a problem with my connections map for my web socket not maintaining s...

1984 Ford Laser•1/10/25, 8:42 PM

what happens when you do

this.state.getWebSockets()

this.state.getWebSockets()

Hharshil1712 Hey, I have used PartyServer and love it because it makes it takes away a lot of...

ray•1/10/25, 11:45 PM

I've been trying to set up partyserver for my use case and was wondering if you could share a bit of your experience; i have multiple durable objects that handle different logic and I'm not sure how best to run local dev and deploy

ray•1/10/25, 11:48 PM

Should each DO be defined with it's own wrangler.toml and have a root package.json that runs

wrangler dev

wrangler dev

in each folder? Or should i have all the DO bindings defined on a root wrangler.toml? In my case I have a sveltekit app that I'm also deploying on a worker, and was wondering if I should be defining all my DO bindings on my sveltekit wrangler.toml

peachneo•1/11/25, 2:48 AM

How do alarm() retries interact with setAlarm() ?

if alarm() throws thereby queueing a retry - will a subsequent call to setAlarm() "reset" the retry?

Rray Should each DO be defined with it's own wrangler.toml and have a root package.js...

Ephemeros•1/11/25, 11:11 AM

i dunno about partyserver but I have that setup, each DO and worker has its own wrangler and they share dbs etc like this

e.g.

durable-objects/authdo

"dev": "wrangler dev -e local --show-interactive-dev-session false --ip 0.0.0.0 --persist-to ../../.wrangler/state",

durable-objects/chatdo
"dev": "wrangler dev -e local --show-interactive-dev-session false --ip 0.0.0.0 --persist-to ../../.wrangler/state",

apps/worker-app
"dev": "wrangler dev -e local --show-interactive-dev-session false --ip 0.0.0.0 --persist-to ../../.wrangler/state",

EEphemeros i dunno about partyserver but I have that setup, each DO and worker has its own ...

ray•1/12/25, 2:28 AM

Appreciate you sharing this! Really helps me wrap my head around how I should structure things, are you also binding your authDO on your worker-app wrangler file?

Rray Appreciate you sharing this! Really helps me wrap my head around how I should st...

Ephemeros•1/12/25, 7:47 AM

Yep, I have some as service binding some as durable object bindings

Ephemeros•1/12/25, 3:19 PM

Totally, also when you separate them and can deploy only what changes it's a superpower, like zero downtime

Ephemeros•1/12/25, 3:19 PM

Especially if you can have multiple deployments for your workers and DOs and you can swap from one to another with a switch, really zero downtime

Ephemeros•1/12/25, 3:20 PM

And then we are back to.. microservices

Ephemeros•1/12/25, 3:21 PM

I made it kinda overkill with local/dev/staging/prod environments but it just was too easy to set that up lol

Rray I've been trying to set up partyserver for my use case and was wondering if you ...

Beefp•1/12/25, 6:25 PM

We started out with 6 DO classes in a monolith worker. In the beginning it was a lot easier to work with (single deploy, no bindings) but we hit perf issues because our monolith bundle was so large and Cf loads it on every Worker request or every individual DO request. We are currently splitting into multiple Workers which means transfer migrations as we DO storage heavily

Personally I'd love if Cloudflare improved support for smarter loading/importing based on whether the code is executing as a Worker or as a DO, and which DO class specifically. Doesn't seem necessary to load everything at once if the Worker scripts are set up the right way

async fetch(request) { const upgradeHeader = request.headers.get("Upgrade"); if (upgradeHeader === "websocket") { const [client, server] = Object.values(new WebSocketPair()); this.state.acceptWebSocket(server); const isFirst = this.sessions.size === 0; server.serializeAttachment({ isFirst }); this.sessions.set(server, { isFirst }); if (!isFirst) { console.log("sessions.size: ", this.sessions.size); // Debug for (let [ws, data] of this.sessions.entries()) { console.log("WS:", ws, "DATA:", data); } // find the connection with session.isFirst === true const [firstWs, firstSession] = [...this.sessions.entries()].find(([_, session]) => session.isFirst) || []; console.log("Found firstWs:", firstWs, "firstSession:", firstSession); if (firstWs) { console.log("Sending sync.") firstWs.send(JSON.stringify({ Evento: "sincronizar_fila", Comando: "" })); } } // When connect, send the stored musics const storedMusics = await this.state.storage.get("musicas"); if (storedMusics) { server.send(JSON.stringify({ Evento: "musicas", Comando: storedMusics })); } return new Response(null, { status: 101, webSocket: client }); } return new Response("The request is not a websocket.", { status: 400 }); }

async webSocketClose(ws) { let session = this.sessions.get(ws); this.sessions.delete(ws); if (session?.isFirst) { console.log("The first. Closing all"); await this.state.storage.delete("musicas"); for (let [otherWs] of this.sessions.entries()) { otherWs.close(); this.sessions.delete(otherWs); } } ws.close(); }

hello all! In all examples I see alarms being scheduled for several seconds in the future. If I want

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