code: function isValidMessage (dataLength, socketWrapper, message) {
    if (message.data && message.data.length >= dataLength && typeof message.data[0] === 'string') {
      return true
    }
  
    socketWrapper.sendError(C.TOPIC.RPC, C.EVENT.INVALID_MESSAGE_DATA, message.raw)
  
    return false
  }
docs: Checks if the incoming message is valid, e.g. if rpcName
  is present for subscribe / unsubscribe messages or if
  rpcName and correlationId is present for rpc calls.
  
  @param   {Number}  dataLength    The expected number of entries in the data array
  @param   {SocketWrapper} socketWrapper
  @param   {Object} message parsed and validated deepstream message
  
  @private
  @returns {Boolean} isValid