Setup config storage on boot, closes #349

lib/broadway/config_storage.ex

@@ -2,12 +2,14 @@ defmodule Broadway.ConfigStorage do
   @moduledoc false
 
   @doc """
-  Optional setup for the configuration storage
+  Optional setup for the configuration storage.
+
+  Invoked when Broadway boots.
   """
   @callback setup() :: :ok
 
   @doc """
-  Lists all broadway names in the config storage
+  Lists all broadway names in the config storage.
   """
   @callback list() :: [term()]
 
@@ -17,12 +19,12 @@ defmodule Broadway.ConfigStorage do
   @callback put(server :: term(), value :: %Broadway.Topology{}) :: term()
 
   @doc """
-  Retrieves a configuration from the underlying storage
+  Retrieves a configuration from the underlying storage.
   """
   @callback get(server :: term()) :: term()
 
   @doc """
-  Deletes a configuration from the underlying storage
+  Deletes a configuration from the underlying storage.
   """
   @callback delete(server :: term()) :: boolean()
 

lib/broadway/config_storage/ets.ex

@@ -10,10 +10,7 @@ defmodule Broadway.ConfigStorage.ETS do
 
   @impl true
   def setup do
-    if :undefined == :ets.whereis(@table) do
-      :ets.new(@table, [:named_table, :public, :set, {:read_concurrency, true}])
-    end
-
+    :ets.new(@table, [:named_table, :public, :set, {:read_concurrency, true}])
     :ok
   end
 

lib/broadway/topology.ex

@@ -47,13 +47,8 @@ defmodule Broadway.Topology do
   @impl true
   def init({module, opts}) do
     Process.flag(:trap_exit, true)
-
     config_storage = ConfigStorage.get_module()
 
-    if Code.ensure_loaded?(config_storage) and function_exported?(config_storage, :setup, 0) do
-      config_storage.setup()
-    end
-
     # We want to invoke this as early as possible otherwise the
     # stacktrace gets deeper and deeper in case of errors.
     {child_specs, opts} = prepare_for_start(module, opts)

mix.exs

@@ -22,7 +22,8 @@ defmodule Broadway.MixProject do
   def application do
     [
       extra_applications: [:logger],
-      env: [config_storage: :persistent_term]
+      env: [config_storage: :persistent_term],
+      mod: {Broadway.Application, []}
     ]
   end