Websocket connection (subscription) is not working

[kvelaro]

Hi, my problem is:
I simply cannot connect to websocket server from graphiql interface
It just writes failed
If I write from console (dev tools) something like
const socket = new WebSocket("wss://...:8080/app/my-app") it connects
If I activate and use websocket client tester (chrome extension) it also works
If I debug websocket server I see server is sending appropriate headers with json content
If I see error log from graphiql I see request headers but I cant see response headers, its empty
Tried to disable all extensions - without success
Killed several days researching
Any help, please

[acao]

@kvelaro are you using the createGraphiQLFetcher() implementation with the expected configuration?

You need to make sure you are using the applicable transport - are you using graphql-ws or the legacy spec?

[kvelaro]

Hi, thank you for reply
We are using this package and at first it was throwing error. When I added to websocket server to the config (just a uri string like wss://....:8080/app/my-app) error has dissapeared and new error as above appeared
Tried to understand package and it seems that jss are located under //unpkg.com/graphiql/graphiql.min.js
To be clearer I have no idea whats the logic there (legacy or graphql-ws). How to point/understand what am I using by default, how to change config ?

[acao]

@kvelaro are you providing the subscription-endpoint option?

[kvelaro]

yeah, of course
I write something like wss://....:8080
In browser I just see dummy message Connection to wss://...:8080 failed

And also I want to point that debugged websocket server (reverb) - it returns appropriate headers, as same as I request through chrome-extension://gobngblklhkgmjhbpbdlkglbhhlafjnh/index.html

With above mentioned extension I connect successfully