Replies: 4 comments 11 replies
-
|
Hi @Koliham :) That being said, while you got the basic schema correct; you have left out the rest of the RPC protocol, which would be my prime suspect for the issues you're experiencing. Primarily not receiving the responses sent back for your RPC (subscribe) call |
Beta Was this translation helpful? Give feedback.
-
|
I've added more tips on how to implement the RPC protocol here for JS: |
Beta Was this translation helpful? Give feedback.
-
|
Hi @orweis and @Koliham Here is some example code. const WebSocket = require("ws");
try {
socketClient = new WebSocket('ws://localhost:3010/pubsub');
socketClient?.on("open", async () => {
await socketClient?.send(
'{"request": {"method": "subscribe", "arguments": {"topics": ["a", "b", "c", "d", "e", "f", "g"]}}}');
socketClient?.on("message", async (data) => {
try {
const request = JSON.parse(data);
const body = JSON.parse(request?.request?.arguments?.data);
const call_id = request?.request?.call_id;
console.log(`request: ${JSON.stringify(request)}`);
console.log(`body: ${JSON.stringify(body)}`);
if (body) {
console.log(JSON.stringify(body));
const topic = body?.topic?.toString() ?? undefined;
console.log(`Webhook Challenged Date: ${JSON.stringify(new Date().toISOString())} | topic: ${topic} | Body: ${JSON.stringify(body)}`);
try {
const notify = {
"response": {
"result": "None",
"result_type": "None",
"call_id": call_id
}
};
console.log(`NOTIFYING ${JSON.stringify(notify)}`);
socketClient?.send(JSON.stringify(notify));
} catch (ex) {
console.log(JSON.stringify(ex));
}
//send heartbeat
//this.socketClient.send("heartbeat");
// }
}
} catch (ex) {
console.log(JSON.stringify(ex));
}
});
});
socketClient?.on("error", (data) => {
console.log(data.toString());
});
socketClient?.on("close", (data) => {
console.log(data.toString());
});
} catch (ex) {
console.log(JSON.stringify(ex));
} |
Beta Was this translation helpful? Give feedback.
-
|
Wonderful contribution @lohanspies . Thank you :) |
Beta Was this translation helpful? Give feedback.
-
|
@lohanspies Is the notify message also needed for publishing? |
Beta Was this translation helpful? Give feedback.
-
|
Hi @bishoyroufael I am not sure but would expect that it is needed to establish the RPC connection. |
Beta Was this translation helpful? Give feedback.
-
|
The "notify" message or more correctly the RPC response, is required for every RPC call - so the caller can know it was received, and stop waiting for a response. |
Beta Was this translation helpful? Give feedback.
-
|
Hi, I'm writing my own frontend client for fastapi_pubsub and fastapi_websocket_rpc in typescript. See the files in this folder: https://github.com/Open-Pectus/Open-Pectus/tree/e68ca4e9bbc0a08563a355365c7da266cb02f069/openpectus/frontend/src/fastapi_websocket I'm writing it as a consultant on an open source project, and we're interested in giving back to the community, but I have no plan to support it once I'm no longer attached to the project. I've written a client for RPC, one for pubsub exposing promises, and one for pubsub exposing it as RxJs Observables (useful in Angular in particular). There's a number of features not implemented, that I might implement later, but I'm not sure I will need them all:
|
Beta Was this translation helpful? Give feedback.
-
|
Hi sorry for the late reply - been a crazy week at Permit.io ;-) Re: connect / disconnect
|
Beta Was this translation helpful? Give feedback.
-
|
Hi,
That's absolutely fine, I expect this to be a slow back-and-forth as we're probably both busy.
Yes, I believe there's been some minor misunderstanding, as I've had no problem with unsubscription on websocket closing. My concern about unsubscribing is all about unsubscribing certain topics (and subscribing to others) as the user navigates the frontend application.
And I'm glad it does. I was scared for a minute I had to add code to the pip-distributed files.
I expect I will do that. At least when we get into moving the JS code into the repo as well.
I'm not sure I can for my specific use cases. Is there some technique of proper granularity that I'm missing here, that could avoid this unsubscribe/subscribe behaviour?
To be honest, one of the reasons I didn't include the get_channel_id rpc method is that it's quite cumbersome when I'm trying to be statically typed. The channel knows about the methods, because it needs to call them. To support the get_channel_id method, the methods object also needs to reference the channel, and we have a cycle. It's not a huge problem, but bothersome when I'm trying to avoid things being potentially undefined or null. |
Beta Was this translation helpful? Give feedback.
-
I see now that your challenge here isn't a complex set of subscriptions, but dynamic subscriptions - so yeah I think updating the this dynamically is unavoidable. An option to consider is to have the app layer on top of the pub/sub manage what events are posted to each user, while each suer subscribes to their own unique topic, and then having the dynamic mapping happen there instead of in the pub/sub layer. That being said I think it's fair to use the pub/sub for this mapping.
How about exporting the base interface for a ChannelId the a 3rd file.
I think it's useful, even if just for debugging - but it's not critical - as I don't think the FE implementation needs to have full feature parity with the Python backend, at least not from day one. |
Beta Was this translation helpful? Give feedback.
-
|
Hi @jhk-mjolner, how is this coming along? I'm interested in using it potentially. |
Beta Was this translation helpful? Give feedback.
-
|
@Graeme22 I'm using it and it's working solidly for me. But if you're interested in using my code, you should be able to simply copy from https://github.com/Open-Pectus/Open-Pectus/tree/main/openpectus/frontend/src/fastapi_websocket and remember to add the Having the files yourself will also allow you to extend it with features you might need, that I haven't implemented. |
Beta Was this translation helpful? Give feedback.
-
I was able to extract the payloads sent between client and server to create a Javascript client with websocket (code below).
But there are 2 issues, which I haven't solved yet:
Click to see stack trace!
Frontend Code
Backend Code
Beta Was this translation helpful? Give feedback.
All reactions