```
data
A Primitive or Structured value that contains additional information about the error.
This may be omitted.
The value of this member is defined by the Server (e.g. detailed error information, nested errors etc.).
```
server:
- always has read & write timeouts
- ping handler never blocks the reader (see A)
- sends regular pings to check up on a client
A:
at some point server write buffer can become full, so in order not to
block reads from a client (see
https://github.com/gorilla/websocket/issues/97), server may skip some
pongs. As a result, client may disconnect. But you either have to do
that or block the reader. There is no third way.
client:
- optional read & write timeouts
- optional ping/pong to measure latency
