code: func (c *Context) IsWebsocket() bool {
  	if strings.Contains(strings.ToLower(c.requestHeader("Connection")), "upgrade") &&
  		strings.ToLower(c.requestHeader("Upgrade")) == "websocket" {
  		return true
  	}
  	return false
  }
docs: // IsWebsocket returns true if the request headers indicate that a websocket
  // handshake is being initiated by the client.