phoenix_notes.md

From the Command Line

Action	Command
Start a New Project	mix phx.new project_name
Create DB	mix ecto.create
Start App	mix phx.server
Run App in Interactive Elixir (IEx)	iex -S mix phx.server
Show Routes	mix phx.routes

File Structure

• lib/project_name_web
  • Main application files.
  • Directories for controllers, templates, and views live here.
  • router.ex also lives here.
• assets
  • Static assets
  • Compiled to priv/static
• Questions
  • What goes in lib/app_name?
  • How is it different from what goes in lib/app_name_web?

Core Files

Router

• lib/project_name_web/router.ex
• verb "path", SomeController, :some_action
• resources "/some_resource", SomeResourceController, only: [:index, :show]
• Can also use except.

Controllers

• Controller syntax:

defmodule AppNameWeb.SomeController do
  use AppNameWeb, :controller

  def index(conn, _params) do
    render conn, "index.html"
  end
end

• Leading _ on params required to avoid compiler warnings if we aren't using params in the controller action.
• index.html.eex is a template in the templates directory (lib/app_name_web/templates/some assuming this is an action living in SomeController).

Views

• Render templates.
• Presentation layer for raw data from the controller.
• SomeView goes with SomeController
• Syntax in lib/app_name_web/views/some_view.ex

defmodule AppName.SomeView do
  use AppName, :view
end

Templates

• .eex (Embedded Elixir)
• lib/app_name_web/templates/some_name/index.html.eex syntax:
• Path helpers: <a href="<%= page_path(@conn, :index) %>">To the Welcome Page!</a>
  • page_path(@conn, :show, 14)
  • page_path(@conn, :new)
  • page_path(@conn, :create)
  • page_path(@conn, :edit, 17)
  • page_path(@conn, :update, 17)
  • page_path(@conn, :delete, 24)
  • page_path(@conn, :show, 14, admin: true, some_other_opt: "some value")

<div class="jumbotron">
  <h2>Hello World, from Phoenix!</h2>
</div>

• Template wrapper lives in lib/app_name_web/templates/layout/app.html.eex. Renders a partial with something like <%= render @view_module, @view_template, assigns %>

Ecto

• Installation:
• Add to mix.exs:

defp deps do
  [{:ecto, "~> 2.0"},
   {:postgrex, "~> 0.11"}]
end

• mix deps.get

Stuff for Later

• lib/hello/application.ex starts the Elixir application.
• lib/hello/repo.ex: Ecto repo for interacting with the database.