Turns Ramal's telemetry into PubSub messages, so that open inspectors update as branches change.

Add it to the host's supervision tree after the PubSub and Ramal.Supervisor:

children = [
  {Phoenix.PubSub, name: MyApp.PubSub},
  {Ramal.Supervisor, storage: Ramal.Storage.Postgres, repo: MyApp.Repo},
  {RamalLive.Broadcaster, pubsub: MyApp.PubSub}
]

It attaches telemetry handlers for the branch lifecycle events, [:ramal, :write, :capture] and the end of [:ramal, :merge], and detaches them when it stops. A handler broadcasts {:ramal_live, branch_id, event} on the topic of the branch's domain and nothing else, so no row data travels through the PubSub. Telemetry is node-local, and so are branches (a branch lives on one node), which is why the broadcaster belongs in the tree of every node that runs Ramal.Supervisor.

The inspector works without it, but only shows what was there when the page loaded or after an action made from the page, and says so.

Options

• :pubsub - the host's Phoenix.PubSub name. Required, and the same one given to ramal_inspector/2.

Example

{:ok, _pid} = RamalLive.Broadcaster.start_link(pubsub: MyApp.PubSub)
RamalLive.Broadcaster.attached?(MyApp.PubSub)
#=> true