y-websocket | Websocket Connector for Yjs

(1) Try using the arrow function for the onmessage event:

from: this.connection.onmessage = function (event) {...}

to: this.connection.onmessage = (event) => {...}

or: this.connection.addEventListener("message", (event) => {...});

This way the this.aqiDataList will be available on your component. Inside the event callback.

This should also solve the problem (2) since your array is not being updated on the first place.

This is happening because you are including sectionID in the dependency list of the useEffect within EditorContainer. Because sectionID doesn't change on initial load, this useEffect never fires. I've created a minimal example of this here: https://codesandbox.io/s/focused-babbage-ilx4j?file=/src/App.js

I recommend changing useEffect to useMemo because it runs at least once on initial render of EditorContainer. And you still get the performance benefit because it shouldn't rerun unless sectionID changes.

It seems like you're setting 1 lambda to handle 2 trigger sources, one is IoT service, the other is API Gateway Websocket. Since you use 1 lambda, you have to handle cases when the request is came from sources:

1. While event.requestContext is available when the request is triggered from API Gateway, it is not available when the request is triggered from IoT service (check the IoT event object here https://docs.aws.amazon.com/lambda/latest/dg/services-iotevents.html). So the error you faced (which is Cannot read property 'domainName' of undefined") is about that. You should turn off the lambda trigger from IoT service or handle the request when it comes from IoT Service.
2. I'm not sure about the forbidden error but it is more like you sent unstructured message to API gateway WS, it should be connection.send(JSON.stringify({ action: "sendmessage", data: "hello world" })); instead of connection.send("hello world");

Edited based on post update:

I know ws is there because if I console it it returns a big object with a bunch of functions

Lambda function is not really a server, it is an instance Node environment (that's why it is called FUNCTION), Lambda function doesn't work as the way you think normal Nodejs app does, its container (node environment) usually is halted (or freeze) whenever its job is done so you cannot keep its container alive like a normal server. That's the reason while you can console log the Websocket object, you cannot keep it alive, the NodeJS container was already halted whenever you return/response.

Since you cannot use the Websocket object to open WS connection in Lambda, Amazon offers a way to do that via API Gateway. The way we work with API Gateway Websocket is different than the normal server does too, it would be something like:

• User -> request to API Gateway to connect to websocket -> call Lambda 1 (onconnect function)
• User -> request to API Gateway to send message over Websocket -> call Lambda 2 (sendmessage function)
• User -> request to API Gateway to close connection -> call Lambda 3 (ondisconnect function)

3 settings above is configured in API Gateway (https://docs.aws.amazon.com/apigateway/latest/developerguide/apigateway-websocket-api-integrations.html), logic of 3 functions onconnect, sendmessage, ondisconnect can be handled in 1 lambda or 3 lambda functions depending on the way we design, I check your 3 lambda functions and it looks okay.

I see that you want to use IoT but I'm not sure why. You should test your Websocket API first without anything related to IoT. It would be better if you can tell what you want to achieve here since IoT works more like a publish/subscribe/messaging channel and I don't think it's necessary to use it here.

Updating fastify and fastify-websocket the problem disappeared. What a shame!

I came up with this solution by creating a new cloud instance and installing everything from scratch.

Just npm update.

Thank you all for your support

In case of catching CancelledError, you need to be very careful.

Prior to Python 3.8, it was easy to unintentionally suppress this error with code like this:

Ok I found it out. On WebSocketClose Event in this object there is a method getSession() available.

An important point to note when using WebSocket APIs and trying to return a response from your integration back to the client, as mentioned in this doc:

For a route that is configured to use AWS_PROXY or LAMBDA_PROXY integration, communication is one-way, and API Gateway will not pass the backend response through to the route response automatically. For example, in the case of LAMBDA_PROXY integration, the body that the Lambda function returns will not be returned to the client. If you want the client to receive integration responses, you must define a route response to make two-way communication possible.

So, if you are using a proxy integration, then you cannot return a response back to the client. You would have to use the AWS.ApiGatewayManagementApi.postToConnection method to communicate any data.

Alternatively, if you are using a non-proxy integration, then you can set up a route response for your integration.

Setting the websocket route as below resolved the issue.