Cleanup after adding MR diff's commit_count (try 2)

* processes any pending records which are not migrated yet
* bumps import_export version because of new commits_count attribute
* removes commits_count fallback method

1 files changed, 27 insertions, 0 deletions

diff --git a/db/migrate/20180425131009_assure_commits_count_for_merge_request_diff.rb b/db/migrate/20180425131009_assure_commits_count_for_merge_request_diff.rb
new file mode 100644
index 00000000000..0e991c23bfa
--- /dev/null
+++ b/db/migrate/20180425131009_assure_commits_count_for_merge_request_diff.rb
@@ -0,0 +1,27 @@
+class AssureCommitsCountForMergeRequestDiff < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  class MergeRequestDiff < ActiveRecord::Base
+    self.table_name = 'merge_request_diffs'
+
+    include ::EachBatch
+  end
+
+  def up
+    Gitlab::BackgroundMigration.steal('AddMergeRequestDiffCommitsCount')
+
+    MergeRequestDiff.where(commits_count: nil).each_batch(of: 50) do |batch|
+      range = batch.pluck('MIN(id)', 'MAX(id)').first
+
+      Gitlab::BackgroundMigration::AddMergeRequestDiffCommitsCount.new.perform(*range)
+    end
+  end
+
+  def down
+    # noop
+  end
+end