[Elixir] PhoenixでJSONを返すWeb APIを作る ref: http://qiita.com/FL4TLiN3/items/41ca80cdbfca1956ed78

file0.txt

mix phoenix.gen.html Note notes title:string description:text

file4.txt

curl 'http://localhost:4000/api/notes' -v -X GET -H 'Accept: application/json'

note_controller.ex

#（該当箇所のみ抜粋）
def index(conn, _params) do
  notes = Repo.all(Note)
  # render(conn, "index.html", notes: notes)
  render(conn, :index, notes: notes)
end

note_view.ex

defmodule Demo.NoteView do
  use Demo.Web, :view

  def render("index.json", %{notes: notes}) do
    %{data: render_many(notes, Demo.NoteView, "note.json")}
  end

  def render("show.json", %{story: story}) do
    %{data: render_one(note, Demo.NoteView, "note.json")}
  end

  def render("note.json", %{note: note}) do
    %{id: note.id,
      title: note.title,
      description: note.description}
  end
end

router.ex

defmodule Demo.Router do
  use Demo.Web, :router

  pipeline :browser do
    plug :accepts, ["html"]
    plug :fetch_session
    plug :fetch_flash
    plug :protect_from_forgery
    plug :put_secure_browser_headers
  end

  pipeline :api do
    plug :accepts, ["json"]
  end

  scope "/", Smaug do
    pipe_through :browser

    get "/", PageController, :index
    resources "/notes", NoteController
  end

  scope "/api", Smaug do
    pipe_through :api

    resources "/notes", NoteController, only: [:index, :show]
  end
end