You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: websocket_subprotocol.go
    path of file: ./repos/gqlgen/graphql/handler/transport
    
    the code of the file until where you have to start completion: package transport

import (
	"encoding/json"
	"errors"

	"github.com/gorilla/websocket"
)

const (
	initMessageType messageType = iota
	connectionAckMessageType
	keepAliveMessageType
	connectionErrorMessageType
	connectionCloseMessageType
	startMessageType
	stopMessageType
	dataMessageType
	comp
    
func handleNextReaderError(err error) error {
	// TODO: should we consider all closure scenarios here for the ws connection?
	// for now we only list the error codes from the previous implementation
	if websocket.IsCloseError(err, websocket.CloseNormalClosure, websocket.CloseNoStatusReceived) {
		return errWsConnClosed
	}

	return err
}