* Introduce a connection coder responsible for encoding Cable messages
as WebSocket messages, defaulting to `ActiveSupport::JSON` and duck-
typing to any object responding to `#encode` and `#decode`.
* Consolidate encoding responsibility to the connection. No longer
explicitly JSON-encode from channels or other sources. Pass Cable
messages as Hashes to `#transmit` and rely on it to encode.
* Introduce stream encoders responsible for decoding pubsub messages.
Preserve the currently raw encoding, but make it easy to use JSON.
Same duck type as the connection encoder.
* Revert recent data normalization/quoting (#23649) which treated
`identifier` and `data` values as nested JSON objects rather than as
opaque JSON-encoded strings. That dealt us an awkward hand where we'd
decode JSON strings… or not, but always encode as JSON. Embedding
JSON object values directly is preferably, no extra JSON encoding,
but that should be a purposeful protocol version change rather than
ambiguously, inadvertently supporting multiple message formats.
Similar to the channel streaming side, these values must be strings for
ActionCable to behave as expected. The conversion will allow users to
send string-convertible values and get the expected behavior.
This PR checks all active Action Cable documentation for typos and other
fixes. It aims to make sure that when Rails 5 is released, that the
Action Cable docs are up to snuff with the other documentation included
with Rails.
[ci skip]
* Properly indent code sample in ActionCable::Channel::Streams
* Add a doc comment for #stop_all_streams
* Reformat + add <tt> blocks around code references in ActionCable::Base docs
* Clarify and a little better grammar on ActionCable::RemoteConnections
* Correct indentation and clean up ActionCable::Server::Broadcasting code sample
