Add support for preview cards for local posts/accounts

app/models/preview_card.rb

@@ -32,6 +32,8 @@
 #  link_type                    :integer
 #  published_at                 :datetime
 #  image_description            :string           default(""), not null
+#  target_status_id             :bigint(8)
+#  target_account_id            :bigint(8)
 #
 
 class PreviewCard < ApplicationRecord
@@ -50,6 +52,9 @@ class PreviewCard < ApplicationRecord
   enum :type, { link: 0, photo: 1, video: 2, rich: 3 }
   enum :link_type, { unknown: 0, article: 1 }
 
+  belongs_to :target_status, class_name: 'Status', optional: true, dependent: :destroy
+  belongs_to :target_account, class_name: 'Account', optional: true, dependent: :destroy
+
   has_many :preview_cards_statuses, dependent: :delete_all, inverse_of: :preview_card
   has_many :statuses, through: :preview_cards_statuses
 

app/services/fetch_link_card_service.rb

@@ -26,6 +26,7 @@ class FetchLinkCardService < BaseService
     with_redis_lock("fetch:#{@original_url}") do
       @card = PreviewCard.find_by(url: @url)
       process_url if @card.nil? || @card.updated_at <= 2.weeks.ago || @card.missing_image?
+      attach_local_resource_to_card!
     end
 
     attach_card if @card&.persisted?
@@ -60,6 +61,22 @@ class FetchLinkCardService < BaseService
     end
   end
 
+  def attach_local_resource_to_card!
+    return if @card.nil? || @card.target_account_id.present? || @card.target_status_id.present? || !TagManager.instance.local_url?(@card.url)
+
+    recognized_params = Rails.application.routes.recognize_path(@card.url)
+    return if recognized_params[:action] != 'show'
+
+    case recognized_params[:controller]
+    when 'accounts'
+      account = Account.find_local(recognized_params[:username])
+      @card.update!(target_account: account)
+    when 'statuses'
+      status = Status.find_by(id: recognized_params[:id])
+      @card.update!(target_status: status)
+    end
+  end
+
   def attach_card
     with_redis_lock("attach_card:#{@status.id}") do
       return if @status.with_preview_card?
@@ -85,7 +102,14 @@ class FetchLinkCardService < BaseService
 
   def bad_url?(uri)
     # Avoid local instance URLs and invalid URLs
-    uri.host.blank? || TagManager.instance.local_url?(uri.to_s) || !%w(http https).include?(uri.scheme)
+    uri.host.blank? || bad_local_url?(uri.to_s) || !%w(http https).include?(uri.scheme)
+  end
+
+  def bad_local_url?(uri)
+    return false unless TagManager.instance.local_url?(uri.to_s)
+
+    recognized_params = Rails.application.routes.recognize_path(uri)
+    recognized_params[:action] != 'show' || %w(accounts statuses).exclude?(recognized_params[:controller])
   end
 
   def mention_link?(anchor)

db/migrate/20240326155335_add_target_status_id_to_preview_cards.rb

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+class AddTargetStatusIdToPreviewCards < ActiveRecord::Migration[7.1]
+  disable_ddl_transaction!
+
+  def change
+    add_belongs_to :preview_cards, :target_status, null: true, index: { algorithm: :concurrently, where: 'target_status_id IS NOT NULL' }
+  end
+end

db/migrate/20240326160308_add_target_status_foreign_key_to_preview_cards.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class AddTargetStatusForeignKeyToPreviewCards < ActiveRecord::Migration[7.1]
+  def change
+    add_foreign_key :preview_cards, :statuses, column: :target_status_id, on_delete: :cascade, validate: false
+  end
+end

db/migrate/20240326160903_validate_target_status_foreign_key_on_preview_cards.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class ValidateTargetStatusForeignKeyOnPreviewCards < ActiveRecord::Migration[7.1]
+  def change
+    validate_foreign_key :preview_cards, column: :target_status_id
+  end
+end

db/migrate/20240326161252_add_target_account_id_to_preview_cards.rb

@@ -0,0 +1,9 @@
+# frozen_string_literal: true
+
+class AddTargetAccountIdToPreviewCards < ActiveRecord::Migration[7.1]
+  disable_ddl_transaction!
+
+  def change
+    add_belongs_to :preview_cards, :target_account, null: true, index: { algorithm: :concurrently, where: 'target_account_id IS NOT NULL' }
+  end
+end

db/migrate/20240326161607_add_target_account_foreign_key_to_preview_cards.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class AddTargetAccountForeignKeyToPreviewCards < ActiveRecord::Migration[7.1]
+  def change
+    add_foreign_key :preview_cards, :accounts, column: :target_account_id, on_delete: :cascade, validate: false
+  end
+end

db/migrate/20240326161740_validate_target_account_foreign_key_on_preview_cards.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class ValidateTargetAccountForeignKeyOnPreviewCards < ActiveRecord::Migration[7.1]
+  def change
+    validate_foreign_key :preview_cards, column: :target_account_id
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.1].define(version: 2024_03_22_161611) do
+ActiveRecord::Schema[7.1].define(version: 2024_03_26_161740) do
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
 
@@ -874,6 +874,10 @@ ActiveRecord::Schema[7.1].define(version: 2024_03_22_161611) do
     t.integer "link_type"
     t.datetime "published_at"
     t.string "image_description", default: "", null: false
+    t.bigint "target_status_id"
+    t.bigint "target_account_id"
+    t.index ["target_account_id"], name: "index_preview_cards_on_target_account_id", where: "(target_account_id IS NOT NULL)"
+    t.index ["target_status_id"], name: "index_preview_cards_on_target_status_id", where: "(target_status_id IS NOT NULL)"
     t.index ["url"], name: "index_preview_cards_on_url", unique: true
   end
 
@@ -1347,6 +1351,8 @@ ActiveRecord::Schema[7.1].define(version: 2024_03_22_161611) do
   add_foreign_key "polls", "accounts", on_delete: :cascade
   add_foreign_key "polls", "statuses", on_delete: :cascade
   add_foreign_key "preview_card_trends", "preview_cards", on_delete: :cascade
+  add_foreign_key "preview_cards", "accounts", column: "target_account_id", on_delete: :cascade
+  add_foreign_key "preview_cards", "statuses", column: "target_status_id", on_delete: :cascade
   add_foreign_key "report_notes", "accounts", on_delete: :cascade
   add_foreign_key "report_notes", "reports", on_delete: :cascade
   add_foreign_key "reports", "accounts", column: "action_taken_by_account_id", name: "fk_bca45b75fd", on_delete: :nullify