Heartbeat check-ins and other improvements

Added

• Add support for heartbeat check-ins.

  Use the Appsignal.CheckIn.heartbeat method to send a single heartbeat check-in event from your application. This can be used, for example, in a GenServer's callback:

  Elixir

  @impl true
  def handle_cast({:process_job, job}, jobs) do
    Appsignal.CheckIn.heartbeat("job_processor")
    {:noreply, [job | jobs], {:continue, :process_job}}
  end

  Heartbeats are deduplicated and sent asynchronously, without blocking the current thread. Regardless of how often the .heartbeat method is called, at most one heartbeat with the same identifier will be sent every ten seconds.

  Pass continuous: true as the second argument to send heartbeats continuously during the entire lifetime of the current process. This can be used, for example, during a GenServer's initialisation:

  Elixir

  @impl true
  def init(_arg) do
    Appsignal.CheckIn.heartbeat("my_genserver", continuous: true)
    {:ok, nil}
  end

  You can also use Appsignal.CheckIn.Heartbeat as a supervisor's child process, in order for heartbeats to be sent continuously during the lifetime of the supervisor. This can be used, for example, during an Application's start:

  Elixir

  @impl true
  def start(_type, _args) do
    Supervisor.start_link([
      {Appsignal.CheckIn.Heartbeat, "my_application"}
    ], strategy: :one_for_one, name: MyApplication.Supervisor)
  end

Changed

• Send check-ins concurrently. When calling Appsignal.CheckIn.cron, instead of blocking the current process while the check-in events are sent, schedule them to be sent in a separate process.

View the Elixir package v2.13.0 changelog for more information.