Add Jackalope.Session connection_status/0

Jackalope provides connection status to the implementation of Jackalope.Handler when it changes. However, some situations may require the implementation (or another process) to query the current connection status (i.e. the implementation may be a process that crashed and lost state and needs to rebuild it without waiting for Jackalope connection status to change for the needed event)

lib/jackalope.ex

@@ -194,6 +194,12 @@ defmodule Jackalope do
              ]
   defdelegate publish(topic, payload, opts \\ []), to: Jackalope.Session
 
+  @doc """
+  Get the current MQTT connection status
+  """
+  @spec connection_status() :: :offline | :online
+  defdelegate connection_status(), to: Jackalope.Session
+
   # TODO Get rid of this stuff
   defp connection_options(opts) do
     server =

lib/jackalope/session.ex

@@ -43,6 +43,13 @@ defmodule Jackalope.Session do
     GenServer.cast(__MODULE__, {:report_connection_status, status})
   end
 
+  @spec connection_status() :: :online | :offline
+  def connection_status() do
+    GenServer.call(__MODULE__, :connection_status)
+  catch
+    _, _ -> :offline
+  end
+
   ## MQTT-ing
   @doc false
   @spec publish(String.t(), any(), keyword) :: :ok | {:error, :invalid_qos | :invalid_ttl}
@@ -92,6 +99,11 @@ defmodule Jackalope.Session do
     {:ok, initial_state, {:continue, :consume_work_list}}
   end
 
+  @impl GenServer
+  def handle_call(:connection_status, _from, state) do
+    {:reply, state.connection_status, state}
+  end
+
   @impl GenServer
   # Connection status changes
   def handle_cast({:report_connection_status, :up}, state) do