Actioncable.Channel.broadcast

You're seeing just the function broadcast, go back to Actioncable.Channel module for more information.
Link to this function

broadcast(channel, message)

Examples

iex> Actioncable.Channel("room_1", %{"action"=>"write", "args" => "hello"})

iex> Actioncable.Channel("room_1", %{"action"=>"write"})

Broadcast message to all subscriber from given channel.