Add uploader for GitLab Pages deployments

Use GitLab uploader and override only dynamic_segment
Add settings to gitlab.yml.examle
Use pages path as root directory for local storage
Add settings for pages object storage(not set anywhere ATM)

app/models/pages_deployment.rb

@@ -2,10 +2,14 @@
 
 # PagesDeployment stores a zip archive containing GitLab Pages web-site
 class PagesDeployment < ApplicationRecord
+  include FileStoreMounter
+
   belongs_to :project, optional: false
   belongs_to :ci_build, class_name: 'Ci::Build', optional: true
 
   validates :file, presence: true
   validates :file_store, presence: true, inclusion: { in: ObjectStorage::SUPPORTED_STORES }
   validates :size, presence: true, numericality: { greater_than: 0, only_integer: true }
+
+  mount_file_store_uploader ::Pages::DeploymentUploader
 end

app/uploaders/pages/deployment_uploader.rb

+# frozen_string_literal: true
+
+module Pages
+  class DeploymentUploader < GitlabUploader
+    include ObjectStorage::Concern
+
+    storage_options Gitlab.config.pages
+
+    alias_method :upload, :model
+
+    private
+
+    def dynamic_segment
+      Gitlab::HashedPath.new('pages_deployments', model.id, root_hash: model.project_id)
+    end
+
+    # @hashed is chosen to avoid conflict with namespace name because we use the same directory for storage
+    # @ is not valid character for namespace
+    def base_dir
+      "@hashed"
+    end
+  end
+end

config/gitlab.yml.example

@@ -394,6 +394,14 @@ production: &base
     # File that contains the shared secret key for verifying access for gitlab-pages.
     # Default is '.gitlab_pages_secret' relative to Rails.root (i.e. root of the GitLab app).
     # secret_file: /home/git/gitlab/.gitlab_pages_secret
+    object_store:
+      enabled: false
+      remote_directory: pages # The bucket name
+      connection:
+        provider: AWS
+        aws_access_key_id: AWS_ACCESS_KEY_ID
+        aws_secret_access_key: AWS_SECRET_ACCESS_KEY
+        region: us-east-1
 
   ## Mattermost
   ## For enabling Add to Mattermost button
@@ -1318,6 +1326,14 @@ test:
     # user: YOUR_USERNAME
   pages:
     path: tmp/tests/pages
+    object_store:
+      enabled: false
+      remote_directory: pages # The bucket name
+      connection:
+        provider: AWS
+        aws_access_key_id: AWS_ACCESS_KEY_ID
+        aws_secret_access_key: AWS_SECRET_ACCESS_KEY
+        region: us-east-1
   repositories:
     storages:
       default:

config/initializers/1_settings.rb

@@ -297,6 +297,10 @@ Settings.pages['external_http'] ||= false unless Settings.pages['external_http']
 Settings.pages['external_https'] ||= false unless Settings.pages['external_https'].present?
 Settings.pages['artifacts_server'] ||= Settings.pages['enabled'] if Settings.pages['artifacts_server'].nil?
 Settings.pages['secret_file'] ||= Rails.root.join('.gitlab_pages_secret')
+# We want pages zip archives to be stored on the same directory as old pages hierarchical structure
+# this will allow us to easier migrate existing instances with NFS
+Settings.pages['storage_path']      = Settings.pages['path']
+Settings.pages['object_store']      = ObjectStoreSettings.legacy_parse(Settings.pages['object_store'])
 
 #
 # Geo

spec/factories/pages_deployments.rb

@@ -4,9 +4,12 @@ FactoryBot.define do
   factory :pages_deployment, class: 'PagesDeployment' do
     project
     file_store { ObjectStorage::SUPPORTED_STORES.first }
-    size { 1.megabytes }
 
-    # TODO: replace with proper file uploaded in https://gitlab.com/gitlab-org/gitlab/-/issues/245295
-    file { "dummy string" }
+    after(:build) do |deployment, _evaluator|
+      deployment.file = fixture_file_upload(
+        Rails.root.join("spec/fixtures/pages.zip")
+      )
+      deployment.size = deployment.file.size
+    end
   end
 end

spec/support/helpers/stub_object_storage.rb

@@ -89,6 +89,13 @@ module StubObjectStorage
                                  **params)
   end
 
+  def stub_pages_object_storage(uploader = described_class, **params)
+    stub_object_storage_uploader(config: Gitlab.config.pages.object_store,
+                                 uploader: uploader,
+                                 remote_directory: 'pages',
+                                 **params)
+  end
+
   def stub_object_storage_multipart_init(endpoint, upload_id = "upload_id")
     stub_request(:post, %r{\A#{endpoint}tmp/uploads/[a-z0-9-]*\?uploads\z})
       .to_return status: 200, body: <<-EOS.strip_heredoc

spec/uploaders/pages/deployment_uploader_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Pages::DeploymentUploader do
+  let(:pages_deployment) { create(:pages_deployment) }
+  let(:uploader) { described_class.new(pages_deployment, :file) }
+
+  subject { uploader }
+
+  it_behaves_like "builds correct paths",
+                  store_dir: %r[/\h{2}/\h{2}/\h{64}/pages_deployments/\d+],
+                  cache_dir: %r[pages/@hashed/tmp/cache],
+                  work_dir: %r[pages/@hashed/tmp/work]
+
+  context 'when object store is REMOTE' do
+    before do
+      stub_pages_object_storage
+    end
+
+    include_context 'with storage', described_class::Store::REMOTE
+
+    it_behaves_like 'builds correct paths', store_dir: %r[\A\h{2}/\h{2}/\h{64}/pages_deployments/\d+\z]
+  end
+
+  context 'when file is stored in valid local_path' do
+    let(:file) do
+      fixture_file_upload("spec/fixtures/pages.zip")
+    end
+
+    before do
+      uploader.store!(file)
+    end
+
+    subject { uploader.file.path }
+
+    it { is_expected.to match(%r[#{uploader.root}/@hashed/\h{2}/\h{2}/\h{64}/pages_deployments/#{pages_deployment.id}/pages.zip]) }
+  end
+end