Add 'activestorage/' from commit '3f4a7218a4a4923a0e7ce1b2eb0d2888ce30da58'

git-subtree-dir: activestorage
git-subtree-mainline: 0d58e7e478e79c2d6b2a39a4444d2a17a903b2a6
git-subtree-split: 3f4a7218a4a4923a0e7ce1b2eb0d2888ce30da58

65 files changed, 1424 insertions, 0 deletions

diff --git a/activestorage/test/controllers/direct_uploads_controller_test.rb b/activestorage/test/controllers/direct_uploads_controller_test.rb
new file mode 100644
index 0000000000..7185bf2737
--- /dev/null
+++ b/activestorage/test/controllers/direct_uploads_controller_test.rb
@@ -0,0 +1,121 @@
+require "test_helper"
+require "database/setup"
+
+if SERVICE_CONFIGURATIONS[:s3]
+  class ActiveStorage::S3DirectUploadsControllerTest < ActionDispatch::IntegrationTest
+    setup do
+      @old_service = ActiveStorage::Blob.service
+      ActiveStorage::Blob.service = ActiveStorage::Service.configure(:s3, SERVICE_CONFIGURATIONS)
+    end
+
+    teardown do
+      ActiveStorage::Blob.service = @old_service
+    end
+
+    test "creating new direct upload" do
+      checksum = Digest::MD5.base64digest("Hello")
+
+      post rails_direct_uploads_url, params: { blob: {
+        filename: "hello.txt", byte_size: 6, checksum: checksum, content_type: "text/plain" } }
+
+      response.parsed_body.tap do |details|
+        assert_equal ActiveStorage::Blob.find(details["id"]), ActiveStorage::Blob.find_signed(details["signed_id"])
+        assert_equal "hello.txt", details["filename"]
+        assert_equal 6, details["byte_size"]
+        assert_equal checksum, details["checksum"]
+        assert_equal "text/plain", details["content_type"]
+        assert_match /#{SERVICE_CONFIGURATIONS[:s3][:bucket]}\.s3.(\S+)?amazonaws\.com/, details["direct_upload"]["url"]
+        assert_equal({ "Content-Type" => "text/plain", "Content-MD5" => checksum }, details["direct_upload"]["headers"])
+      end
+    end
+  end
+else
+  puts "Skipping S3 Direct Upload tests because no S3 configuration was supplied"
+end
+
+if SERVICE_CONFIGURATIONS[:gcs]
+  class ActiveStorage::GCSDirectUploadsControllerTest < ActionDispatch::IntegrationTest
+    setup do
+      @config = SERVICE_CONFIGURATIONS[:gcs]
+
+      @old_service = ActiveStorage::Blob.service
+      ActiveStorage::Blob.service = ActiveStorage::Service.configure(:gcs, SERVICE_CONFIGURATIONS)
+    end
+
+    teardown do
+      ActiveStorage::Blob.service = @old_service
+    end
+
+    test "creating new direct upload" do
+      checksum = Digest::MD5.base64digest("Hello")
+
+      post rails_direct_uploads_url, params: { blob: {
+        filename: "hello.txt", byte_size: 6, checksum: checksum, content_type: "text/plain" } }
+
+      @response.parsed_body.tap do |details|
+        assert_equal ActiveStorage::Blob.find(details["id"]), ActiveStorage::Blob.find_signed(details["signed_id"])
+        assert_equal "hello.txt", details["filename"]
+        assert_equal 6, details["byte_size"]
+        assert_equal checksum, details["checksum"]
+        assert_equal "text/plain", details["content_type"]
+        assert_match %r{storage\.googleapis\.com/#{@config[:bucket]}}, details["direct_upload"]["url"]
+        assert_equal({ "Content-Type" => "text/plain", "Content-MD5" => checksum }, details["direct_upload"]["headers"])
+      end
+    end
+  end
+else
+  puts "Skipping GCS Direct Upload tests because no GCS configuration was supplied"
+end
+
+if SERVICE_CONFIGURATIONS[:azure]
+  class ActiveStorage::AzureDirectUploadsControllerTest < ActionDispatch::IntegrationTest
+    setup do
+      @config = SERVICE_CONFIGURATIONS[:azure]
+
+      @old_service = ActiveStorage::Blob.service
+      ActiveStorage::Blob.service = ActiveStorage::Service.configure(:azure, SERVICE_CONFIGURATIONS)
+    end
+
+    teardown do
+      ActiveStorage::Blob.service = @old_service
+    end
+
+    test "creating new direct upload" do
+      checksum = Digest::MD5.base64digest("Hello")
+
+      post rails_direct_uploads_url, params: { blob: {
+        filename: "hello.txt", byte_size: 6, checksum: checksum, content_type: "text/plain" } }
+
+      @response.parsed_body.tap do |details|
+        assert_equal ActiveStorage::Blob.find(details["id"]), ActiveStorage::Blob.find_signed(details["signed_id"])
+        assert_equal "hello.txt", details["filename"]
+        assert_equal 6, details["byte_size"]
+        assert_equal checksum, details["checksum"]
+        assert_equal "text/plain", details["content_type"]
+        assert_match %r{#{@config[:storage_account_name]}\.blob\.core\.windows\.net/#{@config[:container]}}, details["direct_upload"]["url"]
+        assert_equal({ "Content-Type" => "text/plain", "Content-MD5" => checksum, "x-ms-blob-type" => "BlockBlob" }, details["direct_upload"]["headers"])
+      end
+    end
+  end
+else
+  puts "Skipping Azure Direct Upload tests because no Azure configuration was supplied"
+end
+
+class ActiveStorage::DiskDirectUploadsControllerTest < ActionDispatch::IntegrationTest
+  test "creating new direct upload" do
+    checksum = Digest::MD5.base64digest("Hello")
+
+    post rails_direct_uploads_url, params: { blob: {
+      filename: "hello.txt", byte_size: 6, checksum: checksum, content_type: "text/plain" } }
+
+    @response.parsed_body.tap do |details|
+      assert_equal ActiveStorage::Blob.find(details["id"]), ActiveStorage::Blob.find_signed(details["signed_id"])
+      assert_equal "hello.txt", details["filename"]
+      assert_equal 6, details["byte_size"]
+      assert_equal checksum, details["checksum"]
+      assert_equal "text/plain", details["content_type"]
+      assert_match /rails\/active_storage\/disk/, details["direct_upload"]["url"]
+      assert_equal({ "Content-Type" => "text/plain" }, details["direct_upload"]["headers"])
+    end
+  end
+end
diff --git a/activestorage/test/controllers/disk_controller_test.rb b/activestorage/test/controllers/disk_controller_test.rb
new file mode 100644
index 0000000000..df7954d6b4
--- /dev/null
+++ b/activestorage/test/controllers/disk_controller_test.rb
@@ -0,0 +1,57 @@
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::DiskControllerTest < ActionDispatch::IntegrationTest
+  test "showing blob inline" do
+    blob = create_blob
+
+    get blob.service_url
+    assert_equal "inline; filename=\"#{blob.filename.base}\"", @response.headers["Content-Disposition"]
+    assert_equal "text/plain", @response.headers["Content-Type"]
+  end
+
+  test "showing blob as attachment" do
+    blob = create_blob
+
+    get blob.service_url(disposition: :attachment)
+    assert_equal "attachment; filename=\"#{blob.filename.base}\"", @response.headers["Content-Disposition"]
+    assert_equal "text/plain", @response.headers["Content-Type"]
+  end
+
+
+  test "directly uploading blob with integrity" do
+    data = "Something else entirely!"
+    blob = create_blob_before_direct_upload byte_size: data.size, checksum: Digest::MD5.base64digest(data)
+
+    put blob.service_url_for_direct_upload, params: data, headers: { "Content-Type" => "text/plain" }
+    assert_response :no_content
+    assert_equal data, blob.download
+  end
+
+  test "directly uploading blob without integrity" do
+    data = "Something else entirely!"
+    blob = create_blob_before_direct_upload byte_size: data.size, checksum: Digest::MD5.base64digest("bad data")
+
+    put blob.service_url_for_direct_upload, params: data
+    assert_response :unprocessable_entity
+    assert_not blob.service.exist?(blob.key)
+  end
+
+  test "directly uploading blob with mismatched content type" do
+    data = "Something else entirely!"
+    blob = create_blob_before_direct_upload byte_size: data.size, checksum: Digest::MD5.base64digest(data)
+
+    put blob.service_url_for_direct_upload, params: data, headers: { "Content-Type" => "application/octet-stream" }
+    assert_response :unprocessable_entity
+    assert_not blob.service.exist?(blob.key)
+  end
+
+  test "directly uploading blob with mismatched content length" do
+    data = "Something else entirely!"
+    blob = create_blob_before_direct_upload byte_size: data.size - 1, checksum: Digest::MD5.base64digest(data)
+
+    put blob.service_url_for_direct_upload, params: data, headers: { "Content-Type" => "text/plain" }
+    assert_response :unprocessable_entity
+    assert_not blob.service.exist?(blob.key)
+  end
+end
diff --git a/activestorage/test/controllers/variants_controller_test.rb b/activestorage/test/controllers/variants_controller_test.rb
new file mode 100644
index 0000000000..fa8d15977d
--- /dev/null
+++ b/activestorage/test/controllers/variants_controller_test.rb
@@ -0,0 +1,21 @@
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::VariantsControllerTest < ActionDispatch::IntegrationTest
+  setup do
+    @blob = create_image_blob filename: "racecar.jpg"
+  end
+
+  test "showing variant inline" do
+    get rails_blob_variation_url(
+      filename: @blob.filename,
+      signed_blob_id: @blob.signed_id,
+      variation_key: ActiveStorage::Variation.encode(resize: "100x100"))
+
+    assert_redirected_to /racecar.jpg\?.*disposition=inline/
+
+    image = read_image_variant(@blob.variant(resize: "100x100"))
+    assert_equal 100, image.width
+    assert_equal 67, image.height
+  end
+end
diff --git a/activestorage/test/database/create_users_migration.rb b/activestorage/test/database/create_users_migration.rb
new file mode 100644
index 0000000000..a0b72a90ee
--- /dev/null
+++ b/activestorage/test/database/create_users_migration.rb
@@ -0,0 +1,7 @@
+class ActiveStorageCreateUsers < ActiveRecord::Migration[5.1]
+  def change
+    create_table :users do |t|
+      t.string :name
+    end
+  end
+end
diff --git a/activestorage/test/database/setup.rb b/activestorage/test/database/setup.rb
new file mode 100644
index 0000000000..b12038ee68
--- /dev/null
+++ b/activestorage/test/database/setup.rb
@@ -0,0 +1,6 @@
+require "active_storage/migration"
+require_relative "create_users_migration"
+
+ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:")
+ActiveStorageCreateTables.migrate(:up)
+ActiveStorageCreateUsers.migrate(:up)
diff --git a/activestorage/test/dummy/Rakefile b/activestorage/test/dummy/Rakefile
new file mode 100644
index 0000000000..ed646b6f55
--- /dev/null
+++ b/activestorage/test/dummy/Rakefile
@@ -0,0 +1,3 @@
+require_relative 'config/application'
+
+Rails.application.load_tasks
diff --git a/activestorage/test/dummy/app/assets/config/manifest.js b/activestorage/test/dummy/app/assets/config/manifest.js
new file mode 100644
index 0000000000..a8adebe722
--- /dev/null
+++ b/activestorage/test/dummy/app/assets/config/manifest.js
@@ -0,0 +1,5 @@
+
+//= link_tree ../images
+//= link_directory ../javascripts .js
+//= link_directory ../stylesheets .css
+//= link active_storage_manifest.js
diff --git a/activestorage/test/dummy/app/assets/images/.keep b/activestorage/test/dummy/app/assets/images/.keep
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/app/assets/images/.keep
diff --git a/activestorage/test/dummy/app/assets/javascripts/application.js b/activestorage/test/dummy/app/assets/javascripts/application.js
new file mode 100644
index 0000000000..e54c6461cc
--- /dev/null
+++ b/activestorage/test/dummy/app/assets/javascripts/application.js
@@ -0,0 +1,13 @@
+// This is a manifest file that'll be compiled into application.js, which will include all the files
+// listed below.
+//
+// Any JavaScript/Coffee file within this directory, lib/assets/javascripts, vendor/assets/javascripts,
+// or any plugin's vendor/assets/javascripts directory can be referenced here using a relative path.
+//
+// It's not advisable to add code directly here, but if you do, it'll appear at the bottom of the
+// compiled file. JavaScript code in this file should be added after the last require_* statement.
+//
+// Read Sprockets README (https://github.com/rails/sprockets#sprockets-directives) for details
+// about supported directives.
+//
+//= require_tree .
diff --git a/activestorage/test/dummy/app/assets/stylesheets/application.css b/activestorage/test/dummy/app/assets/stylesheets/application.css
new file mode 100644
index 0000000000..0ebd7fe829
--- /dev/null
+++ b/activestorage/test/dummy/app/assets/stylesheets/application.css
@@ -0,0 +1,15 @@
+/*
+ * This is a manifest file that'll be compiled into application.css, which will include all the files
+ * listed below.
+ *
+ * Any CSS and SCSS file within this directory, lib/assets/stylesheets, vendor/assets/stylesheets,
+ * or any plugin's vendor/assets/stylesheets directory can be referenced here using a relative path.
+ *
+ * You're free to add application-wide styles to this file and they'll appear at the bottom of the
+ * compiled file so the styles you add here take precedence over styles defined in any other CSS/SCSS
+ * files in this directory. Styles in this file should be added after the last require_* statement.
+ * It is generally better to create a new file per style scope.
+ *
+ *= require_tree .
+ *= require_self
+ */
diff --git a/activestorage/test/dummy/app/controllers/application_controller.rb b/activestorage/test/dummy/app/controllers/application_controller.rb
new file mode 100644
index 0000000000..1c07694e9d
--- /dev/null
+++ b/activestorage/test/dummy/app/controllers/application_controller.rb
@@ -0,0 +1,3 @@
+class ApplicationController < ActionController::Base
+  protect_from_forgery with: :exception
+end
diff --git a/activestorage/test/dummy/app/controllers/concerns/.keep b/activestorage/test/dummy/app/controllers/concerns/.keep
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/app/controllers/concerns/.keep
diff --git a/activestorage/test/dummy/app/helpers/application_helper.rb b/activestorage/test/dummy/app/helpers/application_helper.rb
new file mode 100644
index 0000000000..de6be7945c
--- /dev/null
+++ b/activestorage/test/dummy/app/helpers/application_helper.rb
@@ -0,0 +1,2 @@
+module ApplicationHelper
+end
diff --git a/activestorage/test/dummy/app/jobs/application_job.rb b/activestorage/test/dummy/app/jobs/application_job.rb
new file mode 100644
index 0000000000..a009ace51c
--- /dev/null
+++ b/activestorage/test/dummy/app/jobs/application_job.rb
@@ -0,0 +1,2 @@
+class ApplicationJob < ActiveJob::Base
+end
diff --git a/activestorage/test/dummy/app/models/application_record.rb b/activestorage/test/dummy/app/models/application_record.rb
new file mode 100644
index 0000000000..10a4cba84d
--- /dev/null
+++ b/activestorage/test/dummy/app/models/application_record.rb
@@ -0,0 +1,3 @@
+class ApplicationRecord < ActiveRecord::Base
+  self.abstract_class = true
+end
diff --git a/activestorage/test/dummy/app/models/concerns/.keep b/activestorage/test/dummy/app/models/concerns/.keep
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/app/models/concerns/.keep
diff --git a/activestorage/test/dummy/app/views/layouts/application.html.erb b/activestorage/test/dummy/app/views/layouts/application.html.erb
new file mode 100644
index 0000000000..a6eb0174b7
--- /dev/null
+++ b/activestorage/test/dummy/app/views/layouts/application.html.erb
@@ -0,0 +1,14 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>Dummy</title>
+    <%= csrf_meta_tags %>
+
+    <%= stylesheet_link_tag    'application', media: 'all' %>
+    <%= javascript_include_tag 'application' %>
+  </head>
+
+  <body>
+    <%= yield %>
+  </body>
+</html>
diff --git a/activestorage/test/dummy/bin/bundle b/activestorage/test/dummy/bin/bundle
new file mode 100755
index 0000000000..66e9889e8b
--- /dev/null
+++ b/activestorage/test/dummy/bin/bundle
@@ -0,0 +1,3 @@
+#!/usr/bin/env ruby
+ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../../Gemfile', __FILE__)
+load Gem.bin_path('bundler', 'bundle')
diff --git a/activestorage/test/dummy/bin/rails b/activestorage/test/dummy/bin/rails
new file mode 100755
index 0000000000..0739660237
--- /dev/null
+++ b/activestorage/test/dummy/bin/rails
@@ -0,0 +1,4 @@
+#!/usr/bin/env ruby
+APP_PATH = File.expand_path('../config/application', __dir__)
+require_relative '../config/boot'
+require 'rails/commands'
diff --git a/activestorage/test/dummy/bin/rake b/activestorage/test/dummy/bin/rake
new file mode 100755
index 0000000000..17240489f6
--- /dev/null
+++ b/activestorage/test/dummy/bin/rake
@@ -0,0 +1,4 @@
+#!/usr/bin/env ruby
+require_relative '../config/boot'
+require 'rake'
+Rake.application.run
diff --git a/activestorage/test/dummy/bin/yarn b/activestorage/test/dummy/bin/yarn
new file mode 100755
index 0000000000..c2bacef836
--- /dev/null
+++ b/activestorage/test/dummy/bin/yarn
@@ -0,0 +1,11 @@
+#!/usr/bin/env ruby
+VENDOR_PATH = File.expand_path('..', __dir__)
+Dir.chdir(VENDOR_PATH) do
+  begin
+    exec "yarnpkg #{ARGV.join(" ")}"
+  rescue Errno::ENOENT
+    $stderr.puts "Yarn executable was not detected in the system."
+    $stderr.puts "Download Yarn at https://yarnpkg.com/en/docs/install"
+    exit 1
+  end
+end
diff --git a/activestorage/test/dummy/config.ru b/activestorage/test/dummy/config.ru
new file mode 100644
index 0000000000..f7ba0b527b
--- /dev/null
+++ b/activestorage/test/dummy/config.ru
@@ -0,0 +1,5 @@
+# This file is used by Rack-based servers to start the application.
+
+require_relative 'config/environment'
+
+run Rails.application
diff --git a/activestorage/test/dummy/config/application.rb b/activestorage/test/dummy/config/application.rb
new file mode 100644
index 0000000000..03bf7b050d
--- /dev/null
+++ b/activestorage/test/dummy/config/application.rb
@@ -0,0 +1,25 @@
+require_relative 'boot'
+
+require "rails"
+require "active_model/railtie"
+require "active_job/railtie"
+require "active_record/railtie"
+require "action_controller/railtie"
+require "action_view/railtie"
+require "sprockets/railtie"
+#require "action_mailer/railtie"
+#require "rails/test_unit/railtie"
+#require "action_cable/engine"
+
+
+Bundler.require(*Rails.groups)
+require "active_storage"
+
+module Dummy
+  class Application < Rails::Application
+    config.load_defaults 5.1
+
+    config.active_storage.service = :local
+  end
+end
+
diff --git a/activestorage/test/dummy/config/boot.rb b/activestorage/test/dummy/config/boot.rb
new file mode 100644
index 0000000000..c9aef85d40
--- /dev/null
+++ b/activestorage/test/dummy/config/boot.rb
@@ -0,0 +1,5 @@
+# Set up gems listed in the Gemfile.
+ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../../../Gemfile', __dir__)
+
+require 'bundler/setup' if File.exist?(ENV['BUNDLE_GEMFILE'])
+$LOAD_PATH.unshift File.expand_path('../../../lib', __dir__)
diff --git a/activestorage/test/dummy/config/database.yml b/activestorage/test/dummy/config/database.yml
new file mode 100644
index 0000000000..0d02f24980
--- /dev/null
+++ b/activestorage/test/dummy/config/database.yml
@@ -0,0 +1,25 @@
+# SQLite version 3.x
+#   gem install sqlite3
+#
+#   Ensure the SQLite 3 gem is defined in your Gemfile
+#   gem 'sqlite3'
+#
+default: &default
+  adapter: sqlite3
+  pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
+  timeout: 5000
+
+development:
+  <<: *default
+  database: db/development.sqlite3
+
+# Warning: The database defined as "test" will be erased and
+# re-generated from your development database when you run "rake".
+# Do not set this db to the same as development or production.
+test:
+  <<: *default
+  database: db/test.sqlite3
+
+production:
+  <<: *default
+  database: db/production.sqlite3
diff --git a/activestorage/test/dummy/config/environment.rb b/activestorage/test/dummy/config/environment.rb
new file mode 100644
index 0000000000..426333bb46
--- /dev/null
+++ b/activestorage/test/dummy/config/environment.rb
@@ -0,0 +1,5 @@
+# Load the Rails application.
+require_relative 'application'
+
+# Initialize the Rails application.
+Rails.application.initialize!
diff --git a/activestorage/test/dummy/config/environments/development.rb b/activestorage/test/dummy/config/environments/development.rb
new file mode 100644
index 0000000000..503375dede
--- /dev/null
+++ b/activestorage/test/dummy/config/environments/development.rb
@@ -0,0 +1,49 @@
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # In the development environment your application's code is reloaded on
+  # every request. This slows down response time but is perfect for development
+  # since you don't have to restart the web server when you make code changes.
+  config.cache_classes = false
+
+  # Do not eager load code on boot.
+  config.eager_load = false
+
+  # Show full error reports.
+  config.consider_all_requests_local = true
+
+  # Enable/disable caching. By default caching is disabled.
+  if Rails.root.join('tmp/caching-dev.txt').exist?
+    config.action_controller.perform_caching = true
+
+    config.cache_store = :memory_store
+    config.public_file_server.headers = {
+      'Cache-Control' => "public, max-age=#{2.days.seconds.to_i}"
+    }
+  else
+    config.action_controller.perform_caching = false
+
+    config.cache_store = :null_store
+  end
+
+  # Print deprecation notices to the Rails logger.
+  config.active_support.deprecation = :log
+
+  # Raise an error on page load if there are pending migrations.
+  config.active_record.migration_error = :page_load
+
+  # Debug mode disables concatenation and preprocessing of assets.
+  # This option may cause significant delays in view rendering with a large
+  # number of complex assets.
+  config.assets.debug = true
+
+  # Suppress logger output for asset requests.
+  config.assets.quiet = true
+
+  # Raises error for missing translations
+  # config.action_view.raise_on_missing_translations = true
+
+  # Use an evented file watcher to asynchronously detect changes in source code,
+  # routes, locales, etc. This feature depends on the listen gem.
+  # config.file_watcher = ActiveSupport::EventedFileUpdateChecker
+end
diff --git a/activestorage/test/dummy/config/environments/production.rb b/activestorage/test/dummy/config/environments/production.rb
new file mode 100644
index 0000000000..35a30e084a
--- /dev/null
+++ b/activestorage/test/dummy/config/environments/production.rb
@@ -0,0 +1,82 @@
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Code is not reloaded between requests.
+  config.cache_classes = true
+
+  # Eager load code on boot. This eager loads most of Rails and
+  # your application in memory, allowing both threaded web servers
+  # and those relying on copy on write to perform better.
+  # Rake tasks automatically ignore this option for performance.
+  config.eager_load = true
+
+  # Full error reports are disabled and caching is turned on.
+  config.consider_all_requests_local       = false
+  config.action_controller.perform_caching = true
+
+  # Attempt to read encrypted secrets from `config/secrets.yml.enc`.
+  # Requires an encryption key in `ENV["RAILS_MASTER_KEY"]` or
+  # `config/secrets.yml.key`.
+  config.read_encrypted_secrets = true
+
+  # Disable serving static files from the `/public` folder by default since
+  # Apache or NGINX already handles this.
+  config.public_file_server.enabled = ENV['RAILS_SERVE_STATIC_FILES'].present?
+
+  # Compress JavaScripts and CSS.
+  config.assets.js_compressor = :uglifier
+  # config.assets.css_compressor = :sass
+
+  # Do not fallback to assets pipeline if a precompiled asset is missed.
+  config.assets.compile = false
+
+  # `config.assets.precompile` and `config.assets.version` have moved to config/initializers/assets.rb
+
+  # Enable serving of images, stylesheets, and JavaScripts from an asset server.
+  # config.action_controller.asset_host = 'http://assets.example.com'
+
+  # Specifies the header that your server uses for sending files.
+  # config.action_dispatch.x_sendfile_header = 'X-Sendfile' # for Apache
+  # config.action_dispatch.x_sendfile_header = 'X-Accel-Redirect' # for NGINX
+
+  # Mount Action Cable outside main process or domain
+  # config.action_cable.mount_path = nil
+  # config.action_cable.url = 'wss://example.com/cable'
+  # config.action_cable.allowed_request_origins = [ 'http://example.com', /http:\/\/example.*/ ]
+
+  # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
+  # config.force_ssl = true
+
+  # Use the lowest log level to ensure availability of diagnostic information
+  # when problems arise.
+  config.log_level = :debug
+
+  # Prepend all log lines with the following tags.
+  config.log_tags = [ :request_id ]
+
+  # Use a different cache store in production.
+  # config.cache_store = :mem_cache_store
+
+  # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
+  # the I18n.default_locale when a translation cannot be found).
+  config.i18n.fallbacks = true
+
+  # Send deprecation notices to registered listeners.
+  config.active_support.deprecation = :notify
+
+  # Use default logging formatter so that PID and timestamp are not suppressed.
+  config.log_formatter = ::Logger::Formatter.new
+
+  # Use a different logger for distributed setups.
+  # require 'syslog/logger'
+  # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new 'app-name')
+
+  if ENV["RAILS_LOG_TO_STDOUT"].present?
+    logger           = ActiveSupport::Logger.new(STDOUT)
+    logger.formatter = config.log_formatter
+    config.logger    = ActiveSupport::TaggedLogging.new(logger)
+  end
+
+  # Do not dump schema after migrations.
+  config.active_record.dump_schema_after_migration = false
+end
diff --git a/activestorage/test/dummy/config/environments/test.rb b/activestorage/test/dummy/config/environments/test.rb
new file mode 100644
index 0000000000..4380dfc0cd
--- /dev/null
+++ b/activestorage/test/dummy/config/environments/test.rb
@@ -0,0 +1,33 @@
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # The test environment is used exclusively to run your application's
+  # test suite. You never need to work with it otherwise. Remember that
+  # your test database is "scratch space" for the test suite and is wiped
+  # and recreated between test runs. Don't rely on the data there!
+  config.cache_classes = true
+
+  # Do not eager load code on boot. This avoids loading your whole application
+  # just for the purpose of running a single test. If you are using a tool that
+  # preloads Rails for running tests, you may have to set it to true.
+  config.eager_load = false
+
+  # Configure public file server for tests with Cache-Control for performance.
+  config.public_file_server.enabled = true
+  config.public_file_server.headers = {
+    'Cache-Control' => "public, max-age=#{1.hour.seconds.to_i}"
+  }
+
+  # Show full error reports and disable caching.
+  config.consider_all_requests_local       = true
+  config.action_controller.perform_caching = false
+
+  # Raise exceptions instead of rendering exception templates.
+  config.action_dispatch.show_exceptions = false
+
+  # Print deprecation notices to the stderr.
+  config.active_support.deprecation = :stderr
+
+  # Raises error for missing translations
+  # config.action_view.raise_on_missing_translations = true
+end
diff --git a/activestorage/test/dummy/config/initializers/application_controller_renderer.rb b/activestorage/test/dummy/config/initializers/application_controller_renderer.rb
new file mode 100644
index 0000000000..51639b67a0
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/application_controller_renderer.rb
@@ -0,0 +1,6 @@
+# Be sure to restart your server when you modify this file.
+
+# ApplicationController.renderer.defaults.merge!(
+#   http_host: 'example.org',
+#   https: false
+# )
diff --git a/activestorage/test/dummy/config/initializers/assets.rb b/activestorage/test/dummy/config/initializers/assets.rb
new file mode 100644
index 0000000000..4b828e80cb
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/assets.rb
@@ -0,0 +1,14 @@
+# Be sure to restart your server when you modify this file.
+
+# Version of your assets, change this if you want to expire all your assets.
+Rails.application.config.assets.version = '1.0'
+
+# Add additional assets to the asset load path.
+# Rails.application.config.assets.paths << Emoji.images_path
+# Add Yarn node_modules folder to the asset load path.
+Rails.application.config.assets.paths << Rails.root.join('node_modules')
+
+# Precompile additional assets.
+# application.js, application.css, and all non-JS/CSS in the app/assets
+# folder are already added.
+# Rails.application.config.assets.precompile += %w( admin.js admin.css )
diff --git a/activestorage/test/dummy/config/initializers/backtrace_silencers.rb b/activestorage/test/dummy/config/initializers/backtrace_silencers.rb
new file mode 100644
index 0000000000..59385cdf37
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/backtrace_silencers.rb
@@ -0,0 +1,7 @@
+# Be sure to restart your server when you modify this file.
+
+# You can add backtrace silencers for libraries that you're using but don't wish to see in your backtraces.
+# Rails.backtrace_cleaner.add_silencer { |line| line =~ /my_noisy_library/ }
+
+# You can also remove all the silencers if you're trying to debug a problem that might stem from framework code.
+# Rails.backtrace_cleaner.remove_silencers!
diff --git a/activestorage/test/dummy/config/initializers/cookies_serializer.rb b/activestorage/test/dummy/config/initializers/cookies_serializer.rb
new file mode 100644
index 0000000000..5a6a32d371
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/cookies_serializer.rb
@@ -0,0 +1,5 @@
+# Be sure to restart your server when you modify this file.
+
+# Specify a serializer for the signed and encrypted cookie jars.
+# Valid options are :json, :marshal, and :hybrid.
+Rails.application.config.action_dispatch.cookies_serializer = :json
diff --git a/activestorage/test/dummy/config/initializers/filter_parameter_logging.rb b/activestorage/test/dummy/config/initializers/filter_parameter_logging.rb
new file mode 100644
index 0000000000..4a994e1e7b
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/filter_parameter_logging.rb
@@ -0,0 +1,4 @@
+# Be sure to restart your server when you modify this file.
+
+# Configure sensitive parameters which will be filtered from the log file.
+Rails.application.config.filter_parameters += [:password]
diff --git a/activestorage/test/dummy/config/initializers/inflections.rb b/activestorage/test/dummy/config/initializers/inflections.rb
new file mode 100644
index 0000000000..ac033bf9dc
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/inflections.rb
@@ -0,0 +1,16 @@
+# Be sure to restart your server when you modify this file.
+
+# Add new inflection rules using the following format. Inflections
+# are locale specific, and you may define rules for as many different
+# locales as you wish. All of these examples are active by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.plural /^(ox)$/i, '\1en'
+#   inflect.singular /^(ox)en/i, '\1'
+#   inflect.irregular 'person', 'people'
+#   inflect.uncountable %w( fish sheep )
+# end
+
+# These inflection rules are supported but not enabled by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.acronym 'RESTful'
+# end
diff --git a/activestorage/test/dummy/config/initializers/mime_types.rb b/activestorage/test/dummy/config/initializers/mime_types.rb
new file mode 100644
index 0000000000..dc1899682b
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/mime_types.rb
@@ -0,0 +1,4 @@
+# Be sure to restart your server when you modify this file.
+
+# Add new mime types for use in respond_to blocks:
+# Mime::Type.register "text/richtext", :rtf
diff --git a/activestorage/test/dummy/config/initializers/wrap_parameters.rb b/activestorage/test/dummy/config/initializers/wrap_parameters.rb
new file mode 100644
index 0000000000..bbfc3961bf
--- /dev/null
+++ b/activestorage/test/dummy/config/initializers/wrap_parameters.rb
@@ -0,0 +1,14 @@
+# Be sure to restart your server when you modify this file.
+
+# This file contains settings for ActionController::ParamsWrapper which
+# is enabled by default.
+
+# Enable parameter wrapping for JSON. You can disable this by setting :format to an empty array.
+ActiveSupport.on_load(:action_controller) do
+  wrap_parameters format: [:json]
+end
+
+# To enable root element in JSON for ActiveRecord objects.
+# ActiveSupport.on_load(:active_record) do
+#   self.include_root_in_json = true
+# end
diff --git a/activestorage/test/dummy/config/routes.rb b/activestorage/test/dummy/config/routes.rb
new file mode 100644
index 0000000000..1daf9a4121
--- /dev/null
+++ b/activestorage/test/dummy/config/routes.rb
@@ -0,0 +1,2 @@
+Rails.application.routes.draw do
+end
diff --git a/activestorage/test/dummy/config/secrets.yml b/activestorage/test/dummy/config/secrets.yml
new file mode 100644
index 0000000000..77d1fc383a
--- /dev/null
+++ b/activestorage/test/dummy/config/secrets.yml
@@ -0,0 +1,32 @@
+# Be sure to restart your server when you modify this file.
+
+# Your secret key is used for verifying the integrity of signed cookies.
+# If you change this key, all old signed cookies will become invalid!
+
+# Make sure the secret is at least 30 characters and all random,
+# no regular words or you'll be exposed to dictionary attacks.
+# You can use `rails secret` to generate a secure secret key.
+
+# Make sure the secrets in this file are kept private
+# if you're sharing your code publicly.
+
+# Shared secrets are available across all environments.
+
+# shared:
+#   api_key: a1B2c3D4e5F6
+
+# Environmental secrets are only available for that specific environment.
+
+development:
+  secret_key_base: e0ef5744b10d988669be6b2660c259749779964f3dcb487fd6199743b3558e2d89f7681d6a15d16d144e28979cbdae41885f4fb4c2cf56ff92ac22df282ffb66
+
+test:
+  secret_key_base: 6fb1f3a828a8dcd6ac8dc07b43be4a5265ad64379120d417252a1578fe1f790e7b85ade4f95994de1ac8fb78581690de6e3a6ac4af36a0f0139667418c750d05
+
+# Do not keep production secrets in the unencrypted secrets file.
+# Instead, either read values from the environment.
+# Or, use `bin/rails secrets:setup` to configure encrypted secrets
+# and move the `production:` environment over there.
+
+production:
+  secret_key_base: <%= ENV["SECRET_KEY_BASE"] %>
diff --git a/activestorage/test/dummy/config/spring.rb b/activestorage/test/dummy/config/spring.rb
new file mode 100644
index 0000000000..c9119b40c0
--- /dev/null
+++ b/activestorage/test/dummy/config/spring.rb
@@ -0,0 +1,6 @@
+%w(
+  .ruby-version
+  .rbenv-vars
+  tmp/restart.txt
+  tmp/caching-dev.txt
+).each { |path| Spring.watch(path) }
diff --git a/activestorage/test/dummy/config/storage_services.yml b/activestorage/test/dummy/config/storage_services.yml
new file mode 100644
index 0000000000..2c6762e0d6
--- /dev/null
+++ b/activestorage/test/dummy/config/storage_services.yml
@@ -0,0 +1,3 @@
+local:
+  service: Disk
+  root: <%= Rails.root.join("storage") %>
diff --git a/activestorage/test/dummy/lib/assets/.keep b/activestorage/test/dummy/lib/assets/.keep
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/lib/assets/.keep
diff --git a/activestorage/test/dummy/log/.keep b/activestorage/test/dummy/log/.keep
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/log/.keep
diff --git a/activestorage/test/dummy/package.json b/activestorage/test/dummy/package.json
new file mode 100644
index 0000000000..caa2d7bb3f
--- /dev/null
+++ b/activestorage/test/dummy/package.json
@@ -0,0 +1,5 @@
+{
+  "name": "dummy",
+  "private": true,
+  "dependencies": {}
+}
diff --git a/activestorage/test/dummy/public/404.html b/activestorage/test/dummy/public/404.html
new file mode 100644
index 0000000000..2be3af26fc
--- /dev/null
+++ b/activestorage/test/dummy/public/404.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The page you were looking for doesn't exist (404)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/404.html -->
+  <div class="dialog">
+    <div>
+      <h1>The page you were looking for doesn't exist.</h1>
+      <p>You may have mistyped the address or the page may have moved.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
diff --git a/activestorage/test/dummy/public/422.html b/activestorage/test/dummy/public/422.html
new file mode 100644
index 0000000000..c08eac0d1d
--- /dev/null
+++ b/activestorage/test/dummy/public/422.html
@@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The change you wanted was rejected (422)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/422.html -->
+  <div class="dialog">
+    <div>
+      <h1>The change you wanted was rejected.</h1>
+      <p>Maybe you tried to change something you didn't have access to.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
diff --git a/activestorage/test/dummy/public/500.html b/activestorage/test/dummy/public/500.html
new file mode 100644
index 0000000000..78a030af22
--- /dev/null
+++ b/activestorage/test/dummy/public/500.html
@@ -0,0 +1,66 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>We're sorry, but something went wrong (500)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/500.html -->
+  <div class="dialog">
+    <div>
+      <h1>We're sorry, but something went wrong.</h1>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
diff --git a/activestorage/test/dummy/public/apple-touch-icon-precomposed.png b/activestorage/test/dummy/public/apple-touch-icon-precomposed.png
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/public/apple-touch-icon-precomposed.png
diff --git a/activestorage/test/dummy/public/apple-touch-icon.png b/activestorage/test/dummy/public/apple-touch-icon.png
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/public/apple-touch-icon.png
diff --git a/activestorage/test/dummy/public/favicon.ico b/activestorage/test/dummy/public/favicon.ico
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/activestorage/test/dummy/public/favicon.ico
diff --git a/activestorage/test/filename_test.rb b/activestorage/test/filename_test.rb
new file mode 100644
index 0000000000..e448238675
--- /dev/null
+++ b/activestorage/test/filename_test.rb
@@ -0,0 +1,36 @@
+require "test_helper"
+
+class ActiveStorage::FilenameTest < ActiveSupport::TestCase
+  test "sanitize" do
+    "%$|:;/\t\r\n\\".each_char do |character|
+      filename = ActiveStorage::Filename.new("foo#{character}bar.pdf")
+      assert_equal "foo-bar.pdf", filename.sanitized
+      assert_equal "foo-bar.pdf", filename.to_s
+    end
+  end
+
+  test "sanitize transcodes to valid UTF-8" do
+    { "\xF6".force_encoding(Encoding::ISO8859_1) => "ö",
+      "\xC3".force_encoding(Encoding::ISO8859_1) => "Ã",
+      "\xAD" => "�",
+      "\xCF" => "�",
+      "\x00" => "",
+    }.each do |actual, expected|
+      assert_equal expected, ActiveStorage::Filename.new(actual).sanitized
+    end
+  end
+
+  test "strips RTL override chars used to spoof unsafe executables as docs" do
+    # Would be displayed in Windows as "evilexe.pdf" due to the right-to-left
+    # (RTL) override char!
+    assert_equal "evil-fdp.exe", ActiveStorage::Filename.new("evil\u{202E}fdp.exe").sanitized
+  end
+
+  test "compare case-insensitively" do
+    assert_operator ActiveStorage::Filename.new("foobar.pdf"), :==, ActiveStorage::Filename.new("FooBar.PDF")
+  end
+
+  test "compare sanitized" do
+    assert_operator ActiveStorage::Filename.new("foo-bar.pdf"), :==, ActiveStorage::Filename.new("foo\tbar.pdf")
+  end
+end
diff --git a/activestorage/test/fixtures/files/racecar.jpg b/activestorage/test/fixtures/files/racecar.jpg
new file mode 100644
index 0000000000..934b4caa22
--- /dev/null
+++ b/activestorage/test/fixtures/files/racecar.jpg
diff --git a/activestorage/test/models/attachments_test.rb b/activestorage/test/models/attachments_test.rb
new file mode 100644
index 0000000000..82256e1f44
--- /dev/null
+++ b/activestorage/test/models/attachments_test.rb
@@ -0,0 +1,124 @@
+require "test_helper"
+require "database/setup"
+
+# ActiveRecord::Base.logger = Logger.new(STDOUT)
+
+class User < ActiveRecord::Base
+  has_one_attached  :avatar
+  has_many_attached :highlights
+end
+
+class ActiveStorage::AttachmentsTest < ActiveSupport::TestCase
+  include ActiveJob::TestHelper
+
+  setup { @user = User.create!(name: "DHH") }
+
+  teardown { ActiveStorage::Blob.all.each(&:purge) }
+
+  test "attach existing blob" do
+    @user.avatar.attach create_blob(filename: "funky.jpg")
+    assert_equal "funky.jpg", @user.avatar.filename.to_s
+  end
+
+  test "attach existing sgid blob" do
+    @user.avatar.attach create_blob(filename: "funky.jpg").signed_id
+    assert_equal "funky.jpg", @user.avatar.filename.to_s
+  end
+
+  test "attach new blob" do
+    @user.avatar.attach io: StringIO.new("STUFF"), filename: "town.jpg", content_type: "image/jpg"
+    assert_equal "town.jpg", @user.avatar.filename.to_s
+  end
+
+  test "access underlying associations of new blob" do
+    @user.avatar.attach create_blob(filename: "funky.jpg")
+    assert_equal @user, @user.avatar_attachment.record
+    assert_equal @user.avatar_attachment.blob, @user.avatar_blob
+    assert_equal "funky.jpg", @user.avatar_attachment.blob.filename.to_s
+  end
+
+  test "purge attached blob" do
+    @user.avatar.attach create_blob(filename: "funky.jpg")
+    avatar_key = @user.avatar.key
+
+    @user.avatar.purge
+    assert_not @user.avatar.attached?
+    assert_not ActiveStorage::Blob.service.exist?(avatar_key)
+  end
+
+  test "purge attached blob later when the record is destroyed" do
+    @user.avatar.attach create_blob(filename: "funky.jpg")
+    avatar_key = @user.avatar.key
+
+    perform_enqueued_jobs do
+      @user.destroy
+
+      assert_nil ActiveStorage::Blob.find_by(key: avatar_key)
+      assert_not ActiveStorage::Blob.service.exist?(avatar_key)
+    end
+  end
+
+
+  test "attach existing blobs" do
+    @user.highlights.attach create_blob(filename: "funky.jpg"), create_blob(filename: "wonky.jpg")
+
+    assert_equal "funky.jpg", @user.highlights.first.filename.to_s
+    assert_equal "wonky.jpg", @user.highlights.second.filename.to_s
+  end
+
+  test "attach new blobs" do
+    @user.highlights.attach(
+      { io: StringIO.new("STUFF"), filename: "town.jpg", content_type: "image/jpg" },
+      { io: StringIO.new("IT"), filename: "country.jpg", content_type: "image/jpg" })
+
+    assert_equal "town.jpg", @user.highlights.first.filename.to_s
+    assert_equal "country.jpg", @user.highlights.second.filename.to_s
+  end
+
+  test "find attached blobs" do
+    @user.highlights.attach(
+      { io: StringIO.new("STUFF"), filename: "town.jpg", content_type: "image/jpg" },
+      { io: StringIO.new("IT"), filename: "country.jpg", content_type: "image/jpg" })
+
+    highlights = User.where(id: @user.id).with_attached_highlights.first.highlights
+
+    assert_equal "town.jpg", highlights.first.filename.to_s
+    assert_equal "country.jpg", highlights.second.filename.to_s
+  end
+
+  test "access underlying associations of new blobs" do
+    @user.highlights.attach(
+      { io: StringIO.new("STUFF"), filename: "town.jpg", content_type: "image/jpg" },
+      { io: StringIO.new("IT"), filename: "country.jpg", content_type: "image/jpg" })
+
+    assert_equal @user, @user.highlights_attachments.first.record
+    assert_equal @user.highlights_attachments.collect(&:blob).sort, @user.highlights_blobs.sort
+    assert_equal "town.jpg", @user.highlights_attachments.first.blob.filename.to_s
+  end
+
+
+  test "purge attached blobs" do
+    @user.highlights.attach create_blob(filename: "funky.jpg"), create_blob(filename: "wonky.jpg")
+    highlight_keys = @user.highlights.collect(&:key)
+
+    @user.highlights.purge
+    assert_not @user.highlights.attached?
+    assert_not ActiveStorage::Blob.service.exist?(highlight_keys.first)
+    assert_not ActiveStorage::Blob.service.exist?(highlight_keys.second)
+  end
+
+  test "purge attached blobs later when the record is destroyed" do
+    @user.highlights.attach create_blob(filename: "funky.jpg"), create_blob(filename: "wonky.jpg")
+    highlight_keys = @user.highlights.collect(&:key)
+
+    perform_enqueued_jobs do
+      @user.destroy
+
+      assert_nil ActiveStorage::Blob.find_by(key: highlight_keys.first)
+      assert_not ActiveStorage::Blob.service.exist?(highlight_keys.first)
+
+      assert_nil ActiveStorage::Blob.find_by(key: highlight_keys.second)
+      assert_not ActiveStorage::Blob.service.exist?(highlight_keys.second)
+    end
+  end
+end
diff --git a/activestorage/test/models/blob_test.rb b/activestorage/test/models/blob_test.rb
new file mode 100644
index 0000000000..8b14bcec87
--- /dev/null
+++ b/activestorage/test/models/blob_test.rb
@@ -0,0 +1,47 @@
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::BlobTest < ActiveSupport::TestCase
+  test "create after upload sets byte size and checksum" do
+    data = "Hello world!"
+    blob = create_blob data: data
+
+    assert_equal data, blob.download
+    assert_equal data.length, blob.byte_size
+    assert_equal Digest::MD5.base64digest(data), blob.checksum
+  end
+
+  test "text?" do
+    blob = create_blob data: "Hello world!"
+    assert blob.text?
+    assert_not blob.audio?
+  end
+
+  test "download yields chunks" do
+    blob   = create_blob data: "a" * 75.kilobytes
+    chunks = []
+
+    blob.download do |chunk|
+      chunks << chunk
+    end
+
+    assert_equal 2, chunks.size
+    assert_equal "a" * 64.kilobytes, chunks.first
+    assert_equal "a" * 11.kilobytes, chunks.second
+  end
+
+  test "urls expiring in 5 minutes" do
+    blob = create_blob
+
+    freeze_time do
+      assert_equal expected_url_for(blob), blob.service_url
+      assert_equal expected_url_for(blob, disposition: :attachment), blob.service_url(disposition: :attachment)
+    end
+  end
+
+  private
+    def expected_url_for(blob, disposition: :inline)
+      query_string = { content_type: blob.content_type, disposition: disposition }.to_param
+      "/rails/active_storage/disk/#{ActiveStorage.verifier.generate(blob.key, expires_in: 5.minutes, purpose: :blob_key)}/#{blob.filename}?#{query_string}"
+    end
+end
diff --git a/activestorage/test/models/variant_test.rb b/activestorage/test/models/variant_test.rb
new file mode 100644
index 0000000000..7d52f005a7
--- /dev/null
+++ b/activestorage/test/models/variant_test.rb
@@ -0,0 +1,27 @@
+require "test_helper"
+require "database/setup"
+
+class ActiveStorage::VariantTest < ActiveSupport::TestCase
+  setup do
+    @blob = create_image_blob filename: "racecar.jpg"
+  end
+
+  test "resized variation" do
+    variant = @blob.variant(resize: "100x100").processed
+    assert_match /racecar.jpg/, variant.service_url
+
+    image = read_image_variant(variant)
+    assert_equal 100, image.width
+    assert_equal 67, image.height
+  end
+
+  test "resized and monochrome variation" do
+    variant = @blob.variant(resize: "100x100", monochrome: true).processed
+    assert_match /racecar.jpg/, variant.service_url
+
+    image = read_image_variant(variant)
+    assert_equal 100, image.width
+    assert_equal 67, image.height
+    assert_match /Gray/, image.colorspace
+  end
+end
diff --git a/activestorage/test/service/.gitignore b/activestorage/test/service/.gitignore
new file mode 100644
index 0000000000..c102131f3d
--- /dev/null
+++ b/activestorage/test/service/.gitignore
@@ -0,0 +1 @@
+configurations.yml
diff --git a/activestorage/test/service/azure_service_test.rb b/activestorage/test/service/azure_service_test.rb
new file mode 100644
index 0000000000..0ddbac83e7
--- /dev/null
+++ b/activestorage/test/service/azure_service_test.rb
@@ -0,0 +1,14 @@
+require "service/shared_service_tests"
+require "httparty"
+require "uri"
+
+if SERVICE_CONFIGURATIONS[:azure]
+  class ActiveStorage::Service::AzureServiceTest < ActiveSupport::TestCase
+    SERVICE = ActiveStorage::Service.configure(:azure, SERVICE_CONFIGURATIONS)
+
+    include ActiveStorage::Service::SharedServiceTests
+  end
+
+else
+  puts "Skipping Azure Storage Service tests because no Azure configuration was supplied"
+end
diff --git a/activestorage/test/service/configurations-example.yml b/activestorage/test/service/configurations-example.yml
new file mode 100644
index 0000000000..68f6ae4224
--- /dev/null
+++ b/activestorage/test/service/configurations-example.yml
@@ -0,0 +1,31 @@
+# Copy this file to configurations.yml and edit the credentials to match your IAM test account and bucket
+s3:
+  service: S3
+  access_key_id:
+  secret_access_key:
+  region:
+  bucket:
+
+gcs:
+  service: GCS
+  keyfile: {
+    type: "service_account",
+    project_id: "",
+    private_key_id: "",
+    private_key: "",
+    client_email: "",
+    client_id: "",
+    auth_uri: "https://accounts.google.com/o/oauth2/auth",
+    token_uri: "https://accounts.google.com/o/oauth2/token",
+    auth_provider_x509_cert_url: "https://www.googleapis.com/oauth2/v1/certs",
+    client_x509_cert_url: ""
+  }
+  project:
+  bucket:
+
+azure:
+  service: Azure
+  path: ""
+  storage_account_name: ""
+  storage_access_key: ""
+  container: ""
diff --git a/activestorage/test/service/configurator_test.rb b/activestorage/test/service/configurator_test.rb
new file mode 100644
index 0000000000..c69b8d5087
--- /dev/null
+++ b/activestorage/test/service/configurator_test.rb
@@ -0,0 +1,14 @@
+require "service/shared_service_tests"
+
+class ActiveStorage::Service::ConfiguratorTest < ActiveSupport::TestCase
+  test "builds correct service instance based on service name" do
+    service = ActiveStorage::Service::Configurator.build(:foo, foo: { service: "Disk", root: "path" })
+    assert_instance_of ActiveStorage::Service::DiskService, service
+  end
+
+  test "raises error when passing non-existent service name" do
+    assert_raise RuntimeError do
+      ActiveStorage::Service::Configurator.build(:bigfoot, {})
+    end
+  end
+end
diff --git a/activestorage/test/service/disk_service_test.rb b/activestorage/test/service/disk_service_test.rb
new file mode 100644
index 0000000000..a625521601
--- /dev/null
+++ b/activestorage/test/service/disk_service_test.rb
@@ -0,0 +1,12 @@
+require "service/shared_service_tests"
+
+class ActiveStorage::Service::DiskServiceTest < ActiveSupport::TestCase
+  SERVICE = ActiveStorage::Service::DiskService.new(root: File.join(Dir.tmpdir, "active_storage"))
+
+  include ActiveStorage::Service::SharedServiceTests
+
+  test "url generation" do
+    assert_match /rails\/active_storage\/disk\/.*\/avatar\.png\?.+disposition=inline/,
+      @service.url(FIXTURE_KEY, expires_in: 5.minutes, disposition: :inline, filename: "avatar.png", content_type: "image/png")
+  end
+end
diff --git a/activestorage/test/service/gcs_service_test.rb b/activestorage/test/service/gcs_service_test.rb
new file mode 100644
index 0000000000..134a06e3a4
--- /dev/null
+++ b/activestorage/test/service/gcs_service_test.rb
@@ -0,0 +1,42 @@
+require "service/shared_service_tests"
+require "httparty"
+
+if SERVICE_CONFIGURATIONS[:gcs]
+  class ActiveStorage::Service::GCSServiceTest < ActiveSupport::TestCase
+    SERVICE = ActiveStorage::Service.configure(:gcs, SERVICE_CONFIGURATIONS)
+
+    include ActiveStorage::Service::SharedServiceTests
+
+    test "direct upload" do
+      begin
+        key      = SecureRandom.base58(24)
+        data     = "Something else entirely!"
+        checksum = Digest::MD5.base64digest(data)
+        url      = @service.url_for_direct_upload(key, expires_in: 5.minutes, content_type: "text/plain", content_length: data.size, checksum: checksum)
+
+        HTTParty.put(
+          url,
+          body: data,
+          headers: { "Content-Type" => "text/plain", "Content-MD5" => checksum },
+          debug_output: STDOUT
+        )
+
+        assert_equal data, @service.download(key)
+      ensure
+        @service.delete key
+      end
+    end
+
+    test "signed URL generation" do
+      freeze_time do
+        url = SERVICE.bucket.signed_url(FIXTURE_KEY, expires: 120) +
+          "&response-content-disposition=inline%3B+filename%3D%22test.txt%22" +
+          "&response-content-type=text%2Fplain"
+
+        assert_equal url, @service.url(FIXTURE_KEY, expires_in: 2.minutes, disposition: :inline, filename: "test.txt", content_type: "text/plain")
+      end
+    end
+  end
+else
+  puts "Skipping GCS Service tests because no GCS configuration was supplied"
+end
diff --git a/activestorage/test/service/mirror_service_test.rb b/activestorage/test/service/mirror_service_test.rb
new file mode 100644
index 0000000000..129e11d06f
--- /dev/null
+++ b/activestorage/test/service/mirror_service_test.rb
@@ -0,0 +1,62 @@
+require "service/shared_service_tests"
+
+class ActiveStorage::Service::MirrorServiceTest < ActiveSupport::TestCase
+  mirror_config = (1..3).map do |i|
+    [ "mirror_#{i}",
+      service: "Disk",
+      root: Dir.mktmpdir("active_storage_tests_mirror_#{i}") ]
+  end.to_h
+
+  config = mirror_config.merge \
+    mirror:   { service: "Mirror", primary: "primary", mirrors: mirror_config.keys },
+    primary:  { service: "Disk", root: Dir.mktmpdir("active_storage_tests_primary") }
+
+  SERVICE = ActiveStorage::Service.configure :mirror, config
+
+  include ActiveStorage::Service::SharedServiceTests
+
+  test "uploading to all services" do
+    begin
+      data = "Something else entirely!"
+      key  = upload(data, to: @service)
+
+      assert_equal data, SERVICE.primary.download(key)
+      SERVICE.mirrors.each do |mirror|
+        assert_equal data, mirror.download(key)
+      end
+    ensure
+      @service.delete key
+    end
+  end
+
+  test "downloading from primary service" do
+    data = "Something else entirely!"
+    key  = upload(data, to: SERVICE.primary)
+
+    assert_equal data, @service.download(key)
+  end
+
+  test "deleting from all services" do
+    @service.delete FIXTURE_KEY
+    assert_not SERVICE.primary.exist?(FIXTURE_KEY)
+    SERVICE.mirrors.each do |mirror|
+      assert_not mirror.exist?(FIXTURE_KEY)
+    end
+  end
+
+  test "URL generation in primary service" do
+    freeze_time do
+      assert_equal SERVICE.primary.url(FIXTURE_KEY, expires_in: 2.minutes, disposition: :inline, filename: "test.txt", content_type: "text/plain"),
+        @service.url(FIXTURE_KEY, expires_in: 2.minutes, disposition: :inline, filename: "test.txt", content_type: "text/plain")
+    end
+  end
+
+  private
+    def upload(data, to:)
+      SecureRandom.base58(24).tap do |key|
+        io = StringIO.new(data).tap(&:read)
+        @service.upload key, io, checksum: Digest::MD5.base64digest(data)
+        assert io.eof?
+      end
+    end
+end
diff --git a/activestorage/test/service/s3_service_test.rb b/activestorage/test/service/s3_service_test.rb
new file mode 100644
index 0000000000..fa2df263a6
--- /dev/null
+++ b/activestorage/test/service/s3_service_test.rb
@@ -0,0 +1,52 @@
+require "service/shared_service_tests"
+require "httparty"
+
+if SERVICE_CONFIGURATIONS[:s3]
+  class ActiveStorage::Service::S3ServiceTest < ActiveSupport::TestCase
+    SERVICE = ActiveStorage::Service.configure(:s3, SERVICE_CONFIGURATIONS)
+
+    include ActiveStorage::Service::SharedServiceTests
+
+    test "direct upload" do
+      begin
+        key      = SecureRandom.base58(24)
+        data     = "Something else entirely!"
+        checksum = Digest::MD5.base64digest(data)
+        url      = @service.url_for_direct_upload(key, expires_in: 5.minutes, content_type: "text/plain", content_length: data.size, checksum: checksum)
+
+        HTTParty.put(
+          url,
+          body: data,
+          headers: { "Content-Type" => "text/plain", "Content-MD5" => checksum },
+          debug_output: STDOUT
+        )
+
+        assert_equal data, @service.download(key)
+      ensure
+        @service.delete key
+      end
+    end
+
+    test "signed URL generation" do
+      assert_match /#{SERVICE_CONFIGURATIONS[:s3][:bucket]}\.s3.(\S+)?amazonaws.com.*response-content-disposition=inline.*avatar\.png.*response-content-type=image%2Fpng/,
+        @service.url(FIXTURE_KEY, expires_in: 5.minutes, disposition: :inline, filename: "avatar.png", content_type: "image/png")
+    end
+
+    test "uploading with server-side encryption" do
+      config  = SERVICE_CONFIGURATIONS.deep_merge(s3: { upload: { server_side_encryption: "AES256" }})
+      service = ActiveStorage::Service.configure(:s3, config)
+
+      begin
+        key  = SecureRandom.base58(24)
+        data = "Something else entirely!"
+        service.upload key, StringIO.new(data), checksum: Digest::MD5.base64digest(data)
+
+        assert_equal "AES256", service.bucket.object(key).server_side_encryption
+      ensure
+        service.delete key
+      end
+    end
+  end
+else
+  puts "Skipping S3 Service tests because no S3 configuration was supplied"
+end
diff --git a/activestorage/test/service/shared_service_tests.rb b/activestorage/test/service/shared_service_tests.rb
new file mode 100644
index 0000000000..07620d91e4
--- /dev/null
+++ b/activestorage/test/service/shared_service_tests.rb
@@ -0,0 +1,67 @@
+require "test_helper"
+require "active_support/core_ext/securerandom"
+
+module ActiveStorage::Service::SharedServiceTests
+  extend ActiveSupport::Concern
+
+  FIXTURE_KEY  = SecureRandom.base58(24)
+  FIXTURE_DATA = "\211PNG\r\n\032\n\000\000\000\rIHDR\000\000\000\020\000\000\000\020\001\003\000\000\000%=m\"\000\000\000\006PLTE\000\000\000\377\377\377\245\331\237\335\000\000\0003IDATx\234c\370\377\237\341\377_\206\377\237\031\016\2603\334?\314p\1772\303\315\315\f7\215\031\356\024\203\320\275\317\f\367\201R\314\f\017\300\350\377\177\000Q\206\027(\316]\233P\000\000\000\000IEND\256B`\202".force_encoding(Encoding::BINARY)
+
+  included do
+    setup do
+      @service = self.class.const_get(:SERVICE)
+      @service.upload FIXTURE_KEY, StringIO.new(FIXTURE_DATA)
+    end
+
+    teardown do
+      @service.delete FIXTURE_KEY
+    end
+
+    test "uploading with integrity" do
+      begin
+        key  = SecureRandom.base58(24)
+        data = "Something else entirely!"
+        @service.upload(key, StringIO.new(data), checksum: Digest::MD5.base64digest(data))
+
+        assert_equal data, @service.download(key)
+      ensure
+        @service.delete key
+      end
+    end
+
+    test "uploading without integrity" do
+      begin
+        key  = SecureRandom.base58(24)
+        data = "Something else entirely!"
+
+        assert_raises(ActiveStorage::IntegrityError) do
+          @service.upload(key, StringIO.new(data), checksum: Digest::MD5.base64digest("bad data"))
+        end
+
+        assert_not @service.exist?(key)
+      ensure
+        @service.delete key
+      end
+    end
+
+    test "downloading" do
+      assert_equal FIXTURE_DATA, @service.download(FIXTURE_KEY)
+    end
+
+    test "existing" do
+      assert @service.exist?(FIXTURE_KEY)
+      assert_not @service.exist?(FIXTURE_KEY + "nonsense")
+    end
+
+    test "deleting" do
+      @service.delete FIXTURE_KEY
+      assert_not @service.exist?(FIXTURE_KEY)
+    end
+
+    test "deleting nonexistent key" do
+      assert_nothing_raised do
+        @service.delete SecureRandom.base58(24)
+      end
+    end
+  end
+end
diff --git a/activestorage/test/test_helper.rb b/activestorage/test/test_helper.rb
new file mode 100644
index 0000000000..9922c8685c
--- /dev/null
+++ b/activestorage/test/test_helper.rb
@@ -0,0 +1,54 @@
+require File.expand_path("../../test/dummy/config/environment.rb", __FILE__)
+
+require "bundler/setup"
+require "active_support"
+require "active_support/test_case"
+require "active_support/testing/autorun"
+require "byebug"
+
+require "active_job"
+ActiveJob::Base.queue_adapter = :test
+ActiveJob::Base.logger = nil
+
+require "active_storage"
+
+require "yaml"
+SERVICE_CONFIGURATIONS = begin
+  YAML.load_file(File.expand_path("../service/configurations.yml", __FILE__)).deep_symbolize_keys
+rescue Errno::ENOENT
+  puts "Missing service configuration file in test/service/configurations.yml"
+  {}
+end
+
+require "tmpdir"
+ActiveStorage::Blob.service = ActiveStorage::Service::DiskService.new(root: Dir.mktmpdir("active_storage_tests"))
+ActiveStorage::Service.logger = ActiveSupport::Logger.new(STDOUT)
+
+ActiveStorage.verifier = ActiveSupport::MessageVerifier.new("Testing")
+
+class ActiveSupport::TestCase
+  self.file_fixture_path = File.expand_path("../fixtures/files", __FILE__)
+
+  private
+    def create_blob(data: "Hello world!", filename: "hello.txt", content_type: "text/plain")
+      ActiveStorage::Blob.create_after_upload! io: StringIO.new(data), filename: filename, content_type: content_type
+    end
+
+    def create_image_blob(filename: "racecar.jpg", content_type: "image/jpeg")
+      ActiveStorage::Blob.create_after_upload! \
+        io: file_fixture(filename).open,
+        filename: filename, content_type: content_type
+    end
+
+    def create_blob_before_direct_upload(filename: "hello.txt", byte_size:, checksum:, content_type: "text/plain")
+      ActiveStorage::Blob.create_before_direct_upload! filename: filename, byte_size: byte_size, checksum: checksum, content_type: content_type
+    end
+
+    def read_image_variant(variant)
+      MiniMagick::Image.open variant.service.send(:path_for, variant.key)
+    end
+end
+
+require "global_id"
+GlobalID.app = "ActiveStorageExampleApp"
+ActiveRecord::Base.send :include, GlobalID::Identification