Calculate checksums

by copy-pasting in the whole `Upload` class.

Also, fix `Namespace` `model_type` (it should not be `Group`).

1 files changed, 65 insertions, 2 deletions

diff --git a/lib/gitlab/background_migration/populate_untracked_uploads.rb b/lib/gitlab/background_migration/populate_untracked_uploads.rb
index acd424f4558..1773b53bd68 100644
--- a/lib/gitlab/background_migration/populate_untracked_uploads.rb
+++ b/lib/gitlab/background_migration/populate_untracked_uploads.rb
@@ -35,7 +35,7 @@ module Gitlab
           {
             pattern: /\A-\/system\/group\/avatar\/(\d+)/,
             uploader: 'AvatarUploader',
-            model_type: 'Group',
+            model_type: 'Namespace',
           },
           {
             pattern: /\A-\/system\/project\/avatar\/(\d+)/,
@@ -150,8 +150,71 @@ module Gitlab
         end
       end
 
+      # Copy-pasted class for less fragile migration
       class Upload < ActiveRecord::Base
-        self.table_name = 'uploads'
+        self.table_name = 'uploads' # This is the only line different from copy-paste
+
+        # Upper limit for foreground checksum processing
+        CHECKSUM_THRESHOLD = 100.megabytes
+
+        belongs_to :model, polymorphic: true # rubocop:disable Cop/PolymorphicAssociations
+
+        validates :size, presence: true
+        validates :path, presence: true
+        validates :model, presence: true
+        validates :uploader, presence: true
+
+        before_save  :calculate_checksum, if:     :foreground_checksum?
+        after_commit :schedule_checksum,  unless: :foreground_checksum?
+
+        def self.remove_path(path)
+          where(path: path).destroy_all
+        end
+
+        def self.record(uploader)
+          remove_path(uploader.relative_path)
+
+          create(
+            size: uploader.file.size,
+            path: uploader.relative_path,
+            model: uploader.model,
+            uploader: uploader.class.to_s
+          )
+        end
+
+        def absolute_path
+          return path unless relative_path?
+
+          uploader_class.absolute_path(self)
+        end
+
+        def calculate_checksum
+          return unless exist?
+
+          self.checksum = Digest::SHA256.file(absolute_path).hexdigest
+        end
+
+        def exist?
+          File.exist?(absolute_path)
+        end
+
+        private
+
+        def foreground_checksum?
+          size <= CHECKSUM_THRESHOLD
+        end
+
+        def schedule_checksum
+          UploadChecksumWorker.perform_async(id)
+        end
+
+        def relative_path?
+          !path.start_with?('/')
+        end
+
+        def uploader_class
+          Object.const_get(uploader)
+        end
       end
 
       def perform(start_id, end_id)