Running the Phoenix Mix Task

Phoenix has gone through a few iterations of general architecture and project structures, but as of version 1.3, they've stuck on a design that is incredibly elegant and easy to use. Instead of the sometimes clumsy system they previously had, where you had your models, your controllers, your views, and your templates and nothing in between, you can now design things around controllers, views, templates, contexts, and schemas. Before we start diving into what those differences are and why they’re so important, let's talk about the general project structure of a Phoenix application.

The first major thing is that Phoenix applications are considered first-class Elixir projects, so as such follow the same major rules. Generally, Elixir projects should have a test directory and a lib directory. Your test directory is where any new tests you write and any tests you run will live out of lib, on the other hand, is where the actual code for any actual work should go. Let's explore how these directories will get filled out by creating a small sample throwaway Phoenix application.

To create a new Phoenix application, we'll start off by running the mix task phx.new:

$ mix phx.new sampler
* creating sampler/config/config.exs
* creating sampler/config/dev.exs
* creating sampler/config/prod.exs
* creating sampler/config/prod.secret.exs
* creating sampler/config/test.exs
* creating sampler/lib/sampler/application.ex
* creating sampler/lib/sampler.ex
* creating sampler/lib/sampler_web/channels/user_socket.ex
* creating sampler/lib/sampler_web/views/error_helpers.ex
* creating sampler/lib/sampler_web/views/error_view.ex
* creating sampler/lib/sampler_web/endpoint.ex
* creating sampler/lib/sampler_web/router.ex
* creating sampler/lib/sampler_web.ex
* creating sampler/mix.exs
* creating sampler/README.md
* creating sampler/test/support/channel_case.ex
* creating sampler/test/support/conn_case.ex
* creating sampler/test/test_helper.exs
* creating sampler/test/sampler_web/views/error_view_test.exs
* creating sampler/lib/sampler_web/gettext.ex
* creating sampler/priv/gettext/en/LC_MESSAGES/errors.po
* creating sampler/priv/gettext/errors.pot
* creating sampler/lib/sampler/repo.ex
* creating sampler/priv/repo/seeds.exs
* creating sampler/test/support/data_case.ex
* creating sampler/lib/sampler_web/controllers/page_controller.ex
* creating sampler/lib/sampler_web/templates/layout/app.html.eex
* creating sampler/lib/sampler_web/templates/page/index.html.eex
* creating sampler/lib/sampler_web/views/layout_view.ex
* creating sampler/lib/sampler_web/views/page_view.ex
* creating sampler/test/sampler_web/controllers/page_controller_test.exs
* creating sampler/test/sampler_web/views/layout_view_test.exs
* creating sampler/test/sampler_web/views/page_view_test.exs
* creating sampler/.gitignore

* creating sampler/assets/brunch-config.js
* creating sampler/assets/css/app.css
* creating sampler/assets/css/phoenix.css
* creating sampler/assets/js/app.js
* creating sampler/assets/js/socket.js
* creating sampler/assets/package.json
* creating sampler/assets/static/robots.txt
* creating sampler/assets/static/images/phoenix.png
* creating sampler/assets/static/favicon.ico

Fetch and install dependencies? [Yn]

We'll now be asked if we want to fetch and install dependencies. If we say yes, a few things will happen:

1. First off, all of the standard Elixir dependencies that exist for all Phoenix applications will be downloaded from hex and compiled.
2. Next, all of the Node/JavaScript dependencies that Phoenix applications depend on (assuming you did not use the --no-brunch flag when you created your new Phoenix application) will be downloaded from npm and compiled.
3. Assets will be built and set up appropriately via Brunch.

If we say yes, we should see something akin to the following output:

* running mix deps.get
* running mix deps.compile
* running cd assets npm instal node node_modules/brunch/bin/brunch build

We are all set! Go into your application by running:

   $ cd sampler

Then configure your database in config/dev.exs and run:

   $ mix ecto.create

Start your Phoenix app with:

   $ mix phx.server

You can also run your app inside IEx (Interactive Elixir) as:

   $ iex -S mix phx.server

When everything is done, we can enter our new project directory, create our database, and start up our Phoenix server!

$ cd sampler && mix ecto.create
Compiling 13 files (.ex)
Generated sampler app
The database for Sampler.Repo has been created