Arc.Ecto.Paperclip is a library based on Arc.Ecto with a goal of supporting traditional rails paperclip model columns. This is useful when you want to run an elixir application and rails application against the same database schema or if you are planning on migrating to elixir eventually.
Add the latest stable release to your mix.exs
file:
defp deps do
[
{:arc_ecto_paperclip, "~> 0.1.0"}
]
end
Then run mix deps.get
in your shell to fetch the dependencies.
Add a second using macro use Arc.Ecto.Paperclip.Definition
to the top of your Arc definitions.
defmodule MyApp.Avatar do
use Arc.Definition
use Arc.Ecto.Paperclip.Definition
# ...
end
Arc paperclip like attachments should be stored in a set of columns like so.
create table :users do
add :avatar_file_name, :string
add :avatar_file_size, :integer
add :avatar_content_type, :string
add :avatar_updated_at, :datetime
end
Add a using statement use Arc.Ecto.Schema
to the top of your ecto schema, and specify the type of the column in your schema as MyApp.Avatar.Type
.
Attachments can subsequently be passed to Arc's storage though a Changeset cast_paperclip/3
function, following the syntax of cast/3
Notice the attachment macro that generates the appropriate fields for the schema given attachment name.
defmodule MyApp.User do
use MyApp.Web, :model
use Arc.Ecto.Paperclip.Schema
schema "users" do
field :name, :string
attachment :avatar, MyApp.Avatar.Type
end
@doc """
Creates a changeset based on the `data` and `params`.
If no params are provided, an invalid changeset is returned
with no validation performed.
"""
def changeset(user, params \\ :invalid) do
user
|> cast(params, [:name])
|> cast_paperclip(params, [:avatar])
|> validate_required([:name, :avatar_file_name])
end
end
Also notice that when validating required, you should use the actual avatar_file_name
field instead of the attachment field name.
@doc """
Given params of:
%{
"id" => 1,
"user" => %{
"avatar" => %Plug.Upload{
content_type: "image/png",
filename: "selfie.png",
path: "/var/folders/q0/dg42x390000gp/T//plug-1434/multipart-765369-5"}
}
}
"""
def update(conn, %{"id" => id, "user" => user_params}) do
user = Repo.get(User, id)
changeset = User.changeset(user, user_params)
if changeset.valid? do
Repo.update(changeset)
conn
|> put_flash(:info, "User updated successfully.")
|> redirect(to: user_path(conn, :index))
else
render conn, "edit.html", user: user, changeset: changeset
end
end
Both public and signed urls will include the timestamp for cache busting, and are retrieved the exact same way as using Arc directly.
user = Repo.get(User, 1)
# To receive a single rendition:
MyApp.Avatar.url({user.avatar, user}, :thumb)
#=> "https://bucket.s3.amazonaws.com/uploads/avatars/1/thumb.png?v=63601457477"
# To receive all renditions:
MyApp.Avatar.urls({user.avatar, user})
#=> %{original: "https://.../original.png?v=1234", thumb: "https://.../thumb.png?v=1234"}
# To receive a signed url:
MyApp.Avatar.url({user.avatar, user}, signed: true)
MyApp.Avatar.url({user.avatar, user}, :thumb, signed: true)
Copyright 2019 Greg Pardo
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.