43. Active Storage Setup

1rails active_storage:install
2rails db:migrate

1# config/storage.yml
2local:
3  service: Disk
4  root: <%= Rails.root.join("storage") %>

1# config/storage.yml
2amazon:
3  service: S3
4  access_key_id: <%= ENV['AWS_ACCESS_KEY_ID'] %>
5  secret_access_key: <%= ENV['AWS_SECRET_ACCESS_KEY'] %>
6  region: us-east-1
7  bucket: your-bucket-name

1# Gemfile
2gem 'aws-sdk-s3', require: false

1google:
2  service: GCS
3  project: your-project
4  credentials: <%= Rails.root.join("path/to/keyfile.json") %>
5  bucket: your-bucket-name

1# config/environments/development.rb
2config.active_storage.service = :local
3
4# config/environments/production.rb
5config.active_storage.service = :amazon

1class User < ApplicationRecord
2  has_one_attached :avatar
3end

1class Article < ApplicationRecord
2  has_many_attached :images
3end

1<%= form_with model: @user do |f| %>
2  <%= f.label :avatar %>
3  <%= f.file_field :avatar %>
4  <%= f.submit %>
5<% end %>
6
7<!-- Multiple files -->
8<%= form_with model: @article do |f| %>
9  <%= f.label :images %>
10  <%= f.file_field :images, multiple: true %>
11  <%= f.submit %>
12<% end %>

1class UsersController < ApplicationController
2  def create
3    @user = User.new(user_params)
4    if @user.save
5      redirect_to @user
6    else
7      render :new
8    end
9  end
10  
11  def update
12    @user = User.find(params[:id])
13    @user.update(user_params)
14  end
15  
16  private
17  
18  def user_params
19    params.require(:user).permit(:name, :email, :avatar, images: [])
20  end
21end

1# Attach from file path
2user.avatar.attach(io: File.open('/path/to/file.jpg'), filename: 'avatar.jpg')
3
4# Attach from URL
5require 'open-uri'
6user.avatar.attach(io: URI.open('https://example.com/image.jpg'), filename: 'avatar.jpg')
7
8# Attach from uploaded file
9user.avatar.attach(params[:avatar])
10
11# Multiple files
12article.images.attach(params[:images])

1<% if @user.avatar.attached? %>
2  <%= image_tag @user.avatar %>
3  
4  <!-- With size -->
5  <%= image_tag @user.avatar, size: "100x100" %>
6  
7  <!-- Get URL -->
8  <%= url_for(@user.avatar) %>
9  
10  <!-- Rails URL helper -->
11  <%= rails_blob_path(@user.avatar, only_path: true) %>
12<% end %>

1<%= link_to "Download", rails_blob_path(@document.file, disposition: "attachment") %>
2
3<!-- Or inline -->
4<%= link_to "View", rails_blob_path(@document.file, disposition: "inline") %>

1<% @article.images.each do |image| %>
2  <%= image_tag image, class: "gallery-image" %>
3<% end %>

1# Check if attached
2user.avatar.attached?
3
4# Check how many
5article.images.count
6
7# Get blob metadata
8user.avatar.blob.filename
9user.avatar.blob.content_type
10user.avatar.blob.byte_size
11user.avatar.blob.created_at

1# Remove single attachment
2user.avatar.purge       # Synchronously
3user.avatar.purge_later # Background job
4
5# Remove from collection
6article.images.find(blob_id).purge

1<%= form_with model: @user do |f| %>
2  <% if @user.avatar.attached? %>
3    <%= image_tag @user.avatar, size: "100x100" %>
4    <%= f.check_box :remove_avatar, {}, true, false %>
5    <%= f.label :remove_avatar, "Remove avatar" %>
6  <% end %>
7  
8  <%= f.file_field :avatar %>
9  <%= f.submit %>
10<% end %>

1# Controller
2def update
3  @user = User.find(params[:id])
4  @user.avatar.purge if params[:user][:remove_avatar] == "true"
5  @user.update(user_params)
6end

1// app/javascript/application.js
2import * as ActiveStorage from "@rails/activestorage"
3ActiveStorage.start()

1<%= form_with model: @article, local: true do |f| %>
2  <%= f.file_field :images, multiple: true, direct_upload: true %>
3  <%= f.submit %>
4<% end %>

1class User < ApplicationRecord
2  has_one_attached :avatar
3  
4  after_commit :process_avatar, on: [:create, :update]
5  
6  private
7  
8  def process_avatar
9    if avatar.attached?
10      # Do something after avatar is uploaded
11    end
12  end
13end