Max message size and/or number of messages per ProtocolMessage / REST post

[mattheworiordan]

Currently there is no rules to restrict the number of messages or total message size per ProtocolMessage or REST message post

See https://github.com/ably/ably-java/blob/master/src/io/ably/rest/Channel.java#L64 and https://github.com/ably/ably-java/blob/master/src/io/ably/realtime/Channel.java#L455.

There is a separate issue to provide limit info to the client library, however even before that we should perhaps implement some generic limit defaults that can be overridden in ClientOptions. Therefore we should break up messages so that total message size & request size is enforced by the client.

I expect this may need to apply to ably-js as well although yet to review.

┆Issue is synchronized with this Jira Task by Unito

[mattheworiordan]

FYI, an overly simple implementation is included in the Ably Ruby lib - see https://github.com/ably/ably-ruby/blob/master/lib/ably/realtime/channel.rb#L50-L51. This does not factor in message size or allow defaults to be changed so is not very practical.