Consider handling specific exception in the Client.connect

[e5l]

Consider handling specific exception in the Client.connect:

    override suspend fun connect(transport: Transport) {
        // ...
        } catch (error: Throwable) {
            close()
            throw error
        }
    }

[Skrilltrax]

Hi @e5l, I was taking a look at the issue and figured out that there are a lot of exceptions that could get thrown here (especially because the request() method in the try block does json parsing and more). I think one better approach could be that we catch a generic Throwable that we are doing now but instead of throwing an Error, we can instead throw an IllegalStateException with the a message like Error connecting to transport and pass the original error throwable along with it. What do you think about this approach?

    override suspend fun connect(transport: Transport) {
        super.connect(transport)

        try {
            /* ... */
        } catch (error: Throwable) {
            close()
            if (error !is CancellationException) {
                throw IllegalStateException("Error connecting to transport", error)
            } else {
                throw error
            }
        }
    }

[e5l]

Hey, @Skrilltrax, thanks for the investigation. I would also include the transport information in the message (and some unit tests as well). In general, it should be better than what we have right now :)