From 45c366f598637c773244007b726c131186281cdc Mon Sep 17 00:00:00 2001
From: Laura Ghiorghisor <laura.ghiorghisor@digital.cabinet-office.gov.uk>
Date: Thu, 2 Nov 2023 16:57:33 +0000
Subject: [PATCH] Add rake task to migrate TopicalEventFeaturing

Migrating all TopicalEventFeaturing to use a new data class to manage their
image assets. We are reusing FeaturedImageData as this intermediary class,
in the same way AttachmentData works for attachments and their assets.

The rake task will create a new FeaturedImageData for each pre-existing image
and populate its respective assets for each image variant.
---
 app/models/topical_event_featuring.rb         |  2 +
 .../migrate_topical_event_featurings.rake     | 75 +++++++++++++++++++
 2 files changed, 77 insertions(+)
 create mode 100644 lib/tasks/migrate_topical_event_featurings.rake

diff --git a/app/models/topical_event_featuring.rb b/app/models/topical_event_featuring.rb
index 359d7f94bb1..a57108c6563 100644
--- a/app/models/topical_event_featuring.rb
+++ b/app/models/topical_event_featuring.rb
@@ -4,6 +4,8 @@ class TopicalEventFeaturing < ApplicationRecord
   belongs_to :topical_event, inverse_of: :topical_event_featurings
   belongs_to :image, class_name: "TopicalEventFeaturingImageData", foreign_key: :topical_event_featuring_image_data_id
 
+  has_one :image_new, class_name: "FeaturedImageData", as: :featured_imageable, inverse_of: :featured_imageable
+
   accepts_nested_attributes_for :image, reject_if: :all_blank
 
   validates :image, presence: true
diff --git a/lib/tasks/migrate_topical_event_featurings.rake b/lib/tasks/migrate_topical_event_featurings.rake
new file mode 100644
index 00000000000..f6d1639b8ca
--- /dev/null
+++ b/lib/tasks/migrate_topical_event_featurings.rake
@@ -0,0 +1,75 @@
+desc "Migrate topical event featurings to use FeaturedImageData with assets"
+task :migrate_topical_event_featurings, %i[start_id end_id] => :environment do |_, args|
+  puts "Migrating topical event featurings start!"
+  start_id = args[:start_id]
+  end_id = args[:end_id]
+
+  topical_event_featurings = TopicalEventFeaturing.where(id: start_id..end_id).where("topical_event_featuring_image_data_id is not null")
+  puts "Number of topical event featurings found: #{topical_event_featurings.count}"
+  puts "Creating Asset for topical event featuring records from #{start_id} to #{end_id}"
+
+  count = 0
+  asset_counter = 0
+  assetable_type = FeaturedImageData.to_s
+
+  topical_event_featurings.each do |topical_event_featuring|
+    # Ensure we do not replay the same migration
+    next if topical_event_featuring.image_new
+
+    all_variants = topical_event_featuring.image.file.versions.keys.push(:original)
+    assetable = FeaturedImageData.create!(
+      carrierwave_image: topical_event_featuring.image.carrierwave_image,
+      featured_imageable_type: TopicalEventFeaturing.to_s,
+      featured_imageable_id: topical_event_featuring.id,
+    )
+
+    all_variants.each do |variant|
+      path = variant == :original ? topical_event_featuring.image.file.path : topical_event_featuring.image.file.versions[variant].path
+      puts "Creating Asset for path #{path}"
+      asset_counter += 1 if save_asset(assetable, assetable_type, variant, path)
+    end
+
+    count += 1
+  end
+
+  puts "Created assets for #{count} topical event featurings"
+  puts "Created asset counter #{asset_counter}"
+  puts "Migrating topical event featurings finish!"
+end
+
+def save_asset(assetable, assetable_type, variant, path)
+  asset_info = get_asset_data(path)
+  save_asset_id_to_assets(assetable.id, assetable_type, Asset.variants[variant], asset_info[:asset_manager_id], asset_info[:filename])
+rescue GdsApi::HTTPNotFound
+  puts "#{assetable_type} of id##{assetable.id} - could not find asset variant :#{variant} at path #{path}"
+
+  false
+end
+
+def asset_manager
+  Services.asset_manager
+end
+
+def get_asset_data(legacy_url_path)
+  asset_info = {}
+  path = legacy_url_path.sub(/^\//, "")
+  response_hash = asset_manager.whitehall_asset(path).to_hash
+  asset_info[:asset_manager_id] = get_asset_id(response_hash)
+  asset_info[:filename] = get_filename(response_hash)
+
+  asset_info
+end
+
+def get_filename(response)
+  response["name"]
+end
+
+def get_asset_id(response)
+  url = response["id"]
+  url[/\/assets\/(.*)/, 1]
+end
+
+def save_asset_id_to_assets(assetable_id, assetable_type, variant, asset_manager_id, filename)
+  asset = Asset.new(asset_manager_id:, assetable_type:, assetable_id:, variant:, filename:)
+  asset.save!
+end