Artifact

File upload and on-the-fly processing for Elixir

Artifact is under active development, join the fun!

Installation

Add artifact to your list of dependencies in mix.exs:

def deps do
  [{:artifact, "~> 0.4"}]
end

Next, add :artifact to your list of applications:

def application do
  [applications: [:artifact]]
end

Since artifact relies on external processes for transformations, it is recommended that you install the goon middleware. To install, download the package for your system and unzip the contents somewhere in your $PATH:

$ sudo tar zxf goon_darwin_amd64.tar.gz -C /usr/local/bin/

By default artifact uses the imagemagick software which is available via your os package manager, homebrew or from http://www.imagemagick.org/.

Setup in 1-2-3

1. Define a module and use Artifact:

   defmodule ExampleUploader do
     use Artifact, otp_app: :my_app
   end
   

2. Add the supervisor to your supervisor tree:

   def start(_type, _args) do
     import Supervisor.Spec, warn: false
   
     children = [
   	 supervisor(ExampleUploader.Supervisor, [])
     ]
   
     opts = [strategy: :one_for_one, name: MyApp.Supervisor]
    Supervisor.start_link(children, opts)
   end
   

3. Update your router to include the generated plug:

   forward "/images", ExampleUploader.Endpoint
   

Configuration

config :my_app, ExampleUploader,
  asset_host: "http://www.example.com/images",
  asset_url: "/:format/:name",
  default: "placeholder.png",
  formats: %{
    thumb: "convert -'[0]' -resize 50x50 -gravity center +repage -strip jpg:-"
  }

config :my_app, ExampleUploader.Storage,
  type: Artifact.Storage.Local,
  storage_dir: Path.expand("../web/static/assets/images", __DIR__)

config :my_app, ExampleUploader.Pool,
  pool_size: 1

Use

iex> {:ok, name} = ExampleUploader.put(data, name: "profile.png")
iex> name
"profile.png"
iex> {:ok, url} = ExampleUploader.URLHelpers.url(name, :thumb)
"http://www.example.com/images/thumb/profile.png"

Phoenix Integration

Using Aritfact with Phoenix? It may be helpful to update your web/web.ex to alias or import the uploader's url helpers:

def view do
  quote do
    use Phoenix.View, root: "web/templates"

    import Phoenix.Controller, only: [get_csrf_token: 0, get_flash: 2, view_module: 1]

    use Phoenix.HTML

    # We'll use an alias with a shorter name
    alias ExampleUploader.URLHelpers, as: Images

    import BevReviews.Router.Helpers
    import BevReviews.ErrorHelpers
    import BevReviews.Gettext
  end
end

Now we can generate URLs in our markup:

<img class="img-responsive img-thumb" src="<%= Images.url(user.avatar, :thumb) %>" alt="">

The value of user.avatar can be both a filename or a subpath from web/static/assets/images/.

License

Artifact source code is released under Apache 2.0 License.

See LICENSE for more information.