Explore regular polymorphic associations rather than record_gid

app/models/active_storage/attachment.rb

@@ -6,19 +6,11 @@
 class ActiveStorage::Attachment < ActiveRecord::Base
   self.table_name = "active_storage_attachments"
 
+  belongs_to :record, polymorphic: true
   belongs_to :blob, class_name: "ActiveStorage::Blob"
 
   delegate_missing_to :blob
 
-  def record
-    @record ||= GlobalID::Locator.locate(record_gid)
-  end
-
-  def record=(record)
-    @record = record
-    self.record_gid = record&.to_gid
-  end
-
   def purge
     blob.purge
     destroy

lib/active_storage/attached/macros.rb

@@ -16,6 +16,9 @@ def has_one_attached(name, dependent: :purge_later)
         instance_variable_set("@active_storage_attached_#{name}", ActiveStorage::Attached::One.new(name, self))
     end
 
+    has_one :"#{name}_attachment", -> { where(name: name) }, class_name: "ActiveStorage::Attachment", as: :record
+    has_one :"#{name}_blob", through: :"#{name}_attachment"
+
     if dependent == :purge_later
       before_destroy { public_send(name).purge_later }
     end
@@ -38,6 +41,9 @@ def has_many_attached(name, dependent: :purge_later)
         instance_variable_set("@active_storage_attached_#{name}", ActiveStorage::Attached::Many.new(name, self))
     end
 
+    has_many :"#{name}_attachments", -> { where(name: name) }, as: :record, class_name: "ActiveStorage::Attachment"
+    has_many :"#{name}_blobs", through: :"#{name}_attachments"
+
     if dependent == :purge_later
       before_destroy { public_send(name).purge_later }
     end

lib/active_storage/attached/many.rb

@@ -7,14 +7,14 @@ class ActiveStorage::Attached::Many < ActiveStorage::Attached
   # You don't have to call this method to access the attachments' methods as
   # they are all available at the model level.
   def attachments
-    @attachments ||= ActiveStorage::Attachment.where(record_gid: record.to_gid.to_s, name: name)
+    @attachments ||= record.public_send("#{name}_attachments")
   end
 
   # Associates one or several attachments with the current record, saving
   # them to the database.
   def attach(*attachables)
     @attachments = attachments | Array(attachables).flatten.collect do |attachable|
-      ActiveStorage::Attachment.create!(record_gid: record.to_gid.to_s, name: name, blob: create_blob_from(attachable))
+      ActiveStorage::Attachment.create!(record: record, name: name, blob: create_blob_from(attachable))
     end
   end
 

lib/active_storage/attached/one.rb

@@ -7,13 +7,13 @@ class ActiveStorage::Attached::One < ActiveStorage::Attached
   # You don't have to call this method to access the attachment's methods as
   # they are all available at the model level.
   def attachment
-    @attachment ||= ActiveStorage::Attachment.find_by(record_gid: record.to_gid.to_s, name: name)
+    @attachment ||= record.public_send("#{name}_attachment")
   end
 
   # Associates a given attachment with the current record, saving it to the
   # database.
   def attach(attachable)
-    @attachment = ActiveStorage::Attachment.create!(record_gid: record.to_gid.to_s, name: name, blob: create_blob_from(attachable))
+    @attachment = ActiveStorage::Attachment.create!(record: record, name: name, blob: create_blob_from(attachable))
   end
 
   # Checks the presence of the attachment.

lib/active_storage/migration.rb

@@ -14,15 +14,16 @@ def change
 
     create_table :active_storage_attachments do |t|
       t.string  :name
-      t.string  :record_gid
+      t.string  :record_type
+      t.integer :record_id
       t.integer :blob_id
 
       t.datetime :created_at
 
-      t.index :record_gid
       t.index :blob_id
-      t.index [ :record_gid, :name ]
-      t.index [ :record_gid, :blob_id ], unique: true
+      t.index [ :record_type, :record_id ]
+      t.index [ :record_type, :record_id, :name ], name: "index_active_storage_attachments_record_and_name"
+      t.index [ :record_type, :record_id, :blob_id ], name: "index_active_storage_attachments_uniqueness", unique: true
     end
   end
 end

test/models/attachments_test.rb

@@ -68,6 +68,14 @@ class ActiveStorage::AttachmentsTest < ActiveSupport::TestCase
     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" })
+      
+    User.where(id: @user.id).includes(highlights_attachments: :blob).first
+  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)