4 files changed, 24 insertions(+), 6 deletions(-)

M README.md
M lib/servy.ex
M lib/servy/kickstarter.ex
M mix.exs

@@ 1036,3 1036,15 @@ opts = [strategy: :one_for_one, max_restarts: 5, max_seconds: 10]
 # These children will be supervised with the one_for_one strategy, allowing 5 restarts within 10 seconds before error occurs.
 Supervisor.init(children, opts)
 ```
+
+### Final OTP Application
+
+An `application` is a first class citizen in Elixir.
+See [Application](https://hexdocs.pm/elixir/master/Application.html) for more details.
+
+Application environment configuration can be specified directly in the `mix.exs` file, or by `config/config.exs` files.
+  - The `config` directory files are no longer generated by default
+  - Configuration settings set in `config` directory are restricted to this project, if the project is a dependency of another application then the contents of `config/config.exs` are never loaded.
+
+Within the application callback module, the `start/2` callback is what is invoked when calling `iex -S mix` or `mix run` and `mix run --no-halt`.
+

@@ 1,7 1,9 @@
 defmodule Servy do
-  def hello(name) do
-    "Hello, #{name}!"
+  use Application
+
+  def start(_type, _args) do
+    IO.puts "Starting the application..."
+    # {:ok, sup_id} = Servy.Supervisor.start_link()
+    Servy.Supervisor.start_link()
   end
 end
-
-# IO.puts Servy.hello("Elixir")

@@ 21,7 21,8 @@ defmodule Servy.KickStarter do
 
     # server_pid = spawn(Servy.HttpServer, :start, [4000])
     # Process.link(server_pid)
-    server_pid = spawn_link(Servy.HttpServer, :start, [4000])
+    port = Application.get_env(:servy, :port)
+    server_pid = spawn_link(Servy.HttpServer, :start, [port])
 
     Process.register(server_pid, :http_server)
     server_pid

@@ 4,6 4,7 @@ defmodule Servy.MixProject do
   def project do
     [
       app: :servy,
+      description: "A humble HTTP server",
       version: "0.1.0",
       elixir: "~> 1.11",
       start_permanent: Mix.env() == :prod,


@@ 14,7 15,9 @@ defmodule Servy.MixProject do
   # Run "mix help compile.app" to learn about applications.
   def application do
     [
-      extra_applications: [:logger, :eex]
+      extra_applications: [:logger, :eex],
+      mod: {Servy, []},
+      env: [port: 3000]
     ]
   end