parseMessage (common.ts) throws and caches error on each socket message

[FreeRiderBysik]

I'm using graphql-ws with uWebSockets and @urql.

I discovered tons of errors like Message is expected to be an object, but got string, then launching debugger
(Stack is: onmessage->parseMessage->validateMessage).
So, my socket messages are strings, it working correct. Now parseMessage looks like:

try {
    return validateMessage(data);
  } catch {
    if (typeof data !== 'string') {
      throw new Error('Only strings are parsable messages');
    }
    const message = JSON.parse(data, reviver);
    return validateMessage(message);
  }

So it will throw Error and then catch it every time it got string. It is antipattern (exception as flow control) and it can effect performance.
I suppose it will be simpler and work better with something like this:

const message = (typeof data === 'string') ? JSON.parse(data, reviver) : data;
return validateMessage(message);  

[btravel]

Hi,

Looks really strange, especially if consider that stringify is forced on the server side:

https://github.com/enisdenjo/graphql-ws/blob/master/src/server.ts#L691

https://github.com/enisdenjo/graphql-ws/blob/master/src/common.ts#L455

[enisdenjo]

@FreeRiderBysik you're absolutely right, the parsing was too convoluted. I pushed a fix following you suggestion and have released it with v5.10.2.

Thanks for investigating and making a suggestion! Would appreciate it if you could try again and report any other discrepancies.