Move application callback (#764)

lib/hex.ex

@@ -1,8 +1,6 @@
 defmodule Hex do
   @moduledoc false
 
-  use Application
-
   def start() do
     {:ok, _} = Application.ensure_all_started(:hex)
   end
@@ -14,35 +12,15 @@ defmodule Hex do
     end
   end
 
-  def start(_, _) do
-    dev_setup()
-
-    Mix.SCM.append(Hex.SCM)
-    Mix.RemoteConverger.register(Hex.RemoteConverger)
-
-    Hex.Version.start()
-    start_httpc()
-
-    opts = [strategy: :one_for_one, name: Hex.Supervisor]
-    Supervisor.start_link(children(), opts)
+  # For compatability during development
+  def start(start_type, start_args) do
+    Hex.Application.start(start_type, start_args)
   end
 
   def version(), do: unquote(Mix.Project.config()[:version])
   def elixir_version(), do: unquote(System.version())
   def otp_version(), do: unquote(Hex.Utils.otp_version())
 
-  defp start_httpc do
-    :inets.start(:httpc, profile: :hex)
-
-    opts = [
-      max_sessions: 8,
-      max_keep_alive_length: 4,
-      keep_alive_timeout: 120_000
-    ]
-
-    :httpc.set_options(opts, :hex)
-  end
-
   if Version.compare(System.version(), "1.2.0") == :lt do
     def debug?(), do: false
   else
@@ -130,38 +108,6 @@ defmodule Hex do
     end
   end
 
-  if Mix.env() == :test do
-    defp children do
-      import Supervisor.Spec
-
-      [
-        worker(Hex.State, []),
-        worker(Hex.Server, []),
-        worker(Hex.Parallel, [:hex_fetcher])
-      ]
-    end
-  else
-    defp children do
-      import Supervisor.Spec
-
-      [
-        worker(Hex.State, []),
-        worker(Hex.Server, []),
-        worker(Hex.Parallel, [:hex_fetcher]),
-        worker(Hex.Registry.Server, []),
-        worker(Hex.UpdateChecker, [])
-      ]
-    end
-  end
-
-  if Mix.env() in [:dev, :test] do
-    defp dev_setup do
-      :erlang.system_flag(:backtrace_depth, 20)
-    end
-  else
-    defp dev_setup, do: :ok
-  end
-
   def create_tar!(_metadata, [], _output),
     do:
       Mix.raise(

lib/hex/application.ex

@@ -0,0 +1,76 @@
+defmodule Hex.Application do
+  @moduledoc false
+
+  use Application
+
+  def start(_, _) do
+    dev_setup()
+
+    Mix.SCM.append(Hex.SCM)
+    Mix.RemoteConverger.register(Hex.RemoteConverger)
+
+    Hex.Version.start()
+    start_httpc()
+
+    opts = [strategy: :one_for_one, name: Hex.Supervisor]
+    Supervisor.start_link(children(), opts)
+  end
+
+  if Mix.env() in [:dev, :test] do
+    defp dev_setup do
+      :erlang.system_flag(:backtrace_depth, 20)
+    end
+  else
+    defp dev_setup, do: :ok
+  end
+
+  defp start_httpc() do
+    :inets.start(:httpc, profile: :hex)
+
+    opts = [
+      max_sessions: 8,
+      max_keep_alive_length: 4,
+      keep_alive_timeout: 120_000
+    ]
+
+    :httpc.set_options(opts, :hex)
+  end
+
+  defmacrop worker(module) do
+    if Version.compare(System.version(), "1.5.0") == :lt do
+      import Supervisor.Spec
+      quote do: worker(unquote(module), [[]])
+    else
+      quote do: unquote(module)
+    end
+  end
+
+  defmacrop worker(module, args) do
+    if Version.compare(System.version(), "1.5.0") == :lt do
+      import Supervisor.Spec
+      quote do: worker(unquote(module), [unquote(args)])
+    else
+      quote do: {unquote(module), unquote(args)}
+    end
+  end
+
+  if Mix.env() == :test do
+    defp children do
+      [
+        worker(Hex.State),
+        worker(Hex.Server),
+        worker(Hex.Parallel, [:hex_fetcher])
+      ]
+    end
+  else
+    defp children do
+      [
+        worker(Hex.State),
+        worker(Hex.Server),
+        worker(Hex.Parallel, [:hex_fetcher]),
+        worker(Hex.Registry.Server),
+        worker(Hex.UpdateChecker)
+      ]
+    end
+  end
+end

lib/hex/parallel.ex

@@ -7,7 +7,7 @@ defmodule Hex.Parallel do
   use GenServer
   require Logger
 
-  def start_link(name) do
+  def start_link([name]) do
     GenServer.start_link(__MODULE__, [], name: name)
   end
 

lib/hex/server.ex

@@ -5,7 +5,7 @@ defmodule Hex.Server do
 
   @name __MODULE__
 
-  def start_link(opts \\ []) do
+  def start_link(opts) do
     opts = Keyword.put_new(opts, :name, @name)
     GenServer.start_link(__MODULE__, [], opts)
   end

lib/hex/state.ex

@@ -99,11 +99,18 @@ defmodule Hex.State do
     }
   }
 
-  def start_link() do
+  def start_link([]) do
     global_config = Hex.Config.read()
     Agent.start_link(__MODULE__, :init, [global_config], name: @name)
   end
 
+  def child_spec(arg) do
+    %{
+      id: __MODULE__,
+      start: {__MODULE__, :start_link, [arg]}
+    }
+  end
+
   def stop() do
     Agent.stop(@name)
   end

mix.exs

@@ -22,7 +22,7 @@ defmodule Hex.MixProject do
   def application do
     [
       applications: applications(Mix.env()),
-      mod: {Hex, []}
+      mod: {Hex.Application, []}
     ]
   end