def deps do [ {:bow, "~> 0.1.0"}, # for AWS S3 support {:ex_aws, "~> 2.0"}, {:ex_aws_s3, "~> 2.0"}, # for Bow.Exec {:erlexec, "~> 1.7.0"} ] end

defmodule MyUploader do use Bow.Uploader # specify storage directory def store_dir(_file) do "uploads" end end

defmodule AttachmentUploader do use Bow.Uploader # define what versions to generate for given file def versions(_file) do [:original, :thumb] end # keep the origianal file name def filename(file, :original), do: file.name # prepend "thumb_" for thumbnail def filename(file, :thumb), do: "thumb_\#{file.name}" # do nothing with original file def transform(file, :original), do: transform_original(file) # generate image thumbnail def transform(source, target, :thumb) do Bow.Exec.exec source, target, "convert ${input} -strip -gravity Center -resize 250x175^ -extent 250x175 ${output}" end # specify storage directory def store_dir(file) do "attachments/\#{file.scope.id}" end # specify storage options def store_options(_file) do %{acl: :private} end end

# Add `use Bow.Ecto` to the uploader defmodule MyApp.UserAvatarUploader do use Bow.Uploader use Bow.Ecto # <---- HERE # file.scope will be the user struct def store_dir(file) do "users/#{file.scope.id}/avatar" end end # add avatar field to users table defmodule MyApp.Repo.Migrations.AddAvatarToUsers do use Ecto.Migration def change do alter table(:users) do add :avatar, :string end end end # use `MyApp.UserAvatarUploader.Type` as field type defmodule MyApp.User do schema "users" do field :email, :string field :avatar, MyApp.UserAvatarUploader.Type # <-- HERE end def changeset(model \\ %__MODULE__{}, params) do model |> cast(params, [:email, :avatar]) # uncomment to add support for remote_avatar_url params # |> Bow.Ecto.cast_uploads(params, [:avatar]) |> Bow.Ecto.validate() # optional validation using uploader rules end end # create user and save files changeset = User.changeset(%User{}, params) with {:ok, user} <- Repo.insert(changeset), {:ok, user, _} <- Bow.Ecto.store(user) do {:ok, user} end

file = MyUploader.new("path/to/file.png") Bow.url(file) # => url of original file Bow.url(file, :thumb) # => url of thumb version

user = Repo.get(User, 1) Bow.Ecto.url(user, :avatar) # url of avatar original Bow.Ecto.url(user, :avatar, :thumb) # url of avatar thumb Bow.Ecto.url(user, :photo, :thumb, signed: true) # you can pass storage-specific options

defmodule TimestampUploader do use Bow.Uploader use Bow.Ecto def cast(file) do # replace "myfile.png" with "avatar_12343456.png" ts = DateTime.utc_now |> DateTime.to_unix Bow.set(file, :rootname, "avatar_#{ts}") end def store_dir(_file), do: "timestamp" end

defmodule AvatarUploader do # ... def validate(%{ext: ext}) when ext in ~w(.jpg .png), do: :ok def validate(_), do: {:error, :extension_not_allowed} # ... end

# config/test.exs config :bow, storage: Bow.Storage.Local, storage_prefix: "tmp/bow/"