Re-backfill escalation statuses

Incident escalations, behind the incident_escalations
feature flag, previously backfilled records for incident
status. Maintenance of records broke during development,
so this commit backfills the missing records once again.

Changelog: changed

db/migrate/20220321234317_remove_all_issuable_escalation_statuses.rb

+# frozen_string_literal: true
+
+class RemoveAllIssuableEscalationStatuses < Gitlab::Database::Migration[1.0]
+  BATCH_SIZE = 5_000
+
+  disable_ddl_transaction!
+
+  # Removes records from previous backfill. Records for
+  # existing incidents will be created entirely as-needed.
+  #
+  # See db/post_migrate/20211214012507_backfill_incident_issue_escalation_statuses.rb,
+  # & IncidentManagement::IssuableEscalationStatuses::[BuildService,PrepareUpdateService]
+  def up
+    each_batch_range('incident_management_issuable_escalation_statuses', of: BATCH_SIZE) do |min, max|
+      execute <<~SQL
+        DELETE FROM incident_management_issuable_escalation_statuses
+        WHERE id BETWEEN #{min} AND #{max}
+      SQL
+    end
+  end
+
+  def down
+    # no-op
+    #
+    # Potential rollback/re-run should not have impact, as these
+    # records are not required to be present in the application.
+    # The corresponding feature flag is also disabled,
+    # preventing any user-facing access to the records.
+  end
+end

db/post_migrate/20211214012507_backfill_incident_issue_escalation_statuses.rb

 # frozen_string_literal: true
 
 class BackfillIncidentIssueEscalationStatuses < Gitlab::Database::Migration[1.0]
-  MIGRATION = 'BackfillIncidentIssueEscalationStatuses'
-  DELAY_INTERVAL = 2.minutes
-  BATCH_SIZE = 20_000
-
-  disable_ddl_transaction!
-
-  class Issue < ActiveRecord::Base
-    include EachBatch
-
-    self.table_name = 'issues'
-  end
-
-  def up
-    relation = Issue.all
-
-    queue_background_migration_jobs_by_range_at_intervals(
-      relation, MIGRATION, DELAY_INTERVAL, batch_size: BATCH_SIZE, track_jobs: true)
-  end
-
-  def down
+  # Removed in favor of creating records for existing incidents
+  # as-needed. See db/migrate/20220321234317_remove_all_issuable_escalation_statuses.rb.
+  def change
     # no-op
   end
 end

db/schema_migrations/20220321234317

+ba5c1738b7c368ee8e10e390c959538c4d74055b8bc57f652b06ffe3a1c3becf
\ No newline at end of file

lib/gitlab/background_migration/backfill_incident_issue_escalation_statuses.rb

-# frozen_string_literal: true
-
-module Gitlab
-  module BackgroundMigration
-    # BackfillIncidentIssueEscalationStatuses adds
-    # IncidentManagement::IssuableEscalationStatus records for existing Incident issues.
-    # They will be added with no policy, and escalations_started_at as nil.
-    class BackfillIncidentIssueEscalationStatuses
-      def perform(start_id, stop_id)
-        ActiveRecord::Base.connection.execute <<~SQL
-          INSERT INTO incident_management_issuable_escalation_statuses (issue_id, created_at, updated_at)
-            SELECT issues.id, current_timestamp, current_timestamp
-            FROM issues
-            WHERE issues.issue_type = 1
-            AND issues.id BETWEEN #{start_id} AND #{stop_id}
-            ON CONFLICT (issue_id) DO NOTHING;
-        SQL
-
-        mark_job_as_succeeded(start_id, stop_id)
-      end
-
-      private
-
-      def mark_job_as_succeeded(*arguments)
-        ::Gitlab::Database::BackgroundMigrationJob.mark_all_as_succeeded(
-          self.class.name.demodulize,
-          arguments
-        )
-      end
-    end
-  end
-end

spec/lib/gitlab/background_migration/backfill_incident_issue_escalation_statuses_spec.rb

-# frozen_string_literal: true
-
-require 'spec_helper'
-
-RSpec.describe Gitlab::BackgroundMigration::BackfillIncidentIssueEscalationStatuses, schema: 20211214012507 do
-  let(:namespaces)                    { table(:namespaces) }
-  let(:projects)                      { table(:projects) }
-  let(:issues)                        { table(:issues) }
-  let(:issuable_escalation_statuses)  { table(:incident_management_issuable_escalation_statuses) }
-
-  subject(:migration) { described_class.new }
-
-  it 'correctly backfills issuable escalation status records' do
-    namespace = namespaces.create!(name: 'foo', path: 'foo')
-    project = projects.create!(namespace_id: namespace.id)
-
-    issues.create!(project_id: project.id, title: 'issue 1', issue_type: 0)  # non-incident issue
-    issues.create!(project_id: project.id, title: 'incident 1', issue_type: 1)
-    issues.create!(project_id: project.id, title: 'incident 2', issue_type: 1)
-    incident_issue_existing_status = issues.create!(project_id: project.id, title: 'incident 3', issue_type: 1)
-    issuable_escalation_statuses.create!(issue_id: incident_issue_existing_status.id)
-
-    migration.perform(1, incident_issue_existing_status.id)
-
-    expect(issuable_escalation_statuses.count).to eq(3)
-  end
-end

spec/migrations/20211214012507_backfill_incident_issue_escalation_statuses_spec.rb

@@ -10,27 +10,10 @@ RSpec.describe BackfillIncidentIssueEscalationStatuses do
   let(:namespace)   { namespaces.create!(name: 'foo', path: 'foo') }
   let(:project)     { projects.create!(namespace_id: namespace.id) }
 
-  before do
-    stub_const("#{described_class.name}::BATCH_SIZE", 1)
-  end
-
-  it 'schedules jobs for incident issues' do
-    issue_1 = issues.create!(project_id: project.id) # non-incident issue
-    incident_1 = issues.create!(project_id: project.id, issue_type: 1)
-    incident_2 = issues.create!(project_id: project.id, issue_type: 1)
-
-    Sidekiq::Testing.fake! do
-      freeze_time do
-        migrate!
+  # Backfill removed - see db/migrate/20220321234317_remove_all_issuable_escalation_statuses.rb.
+  it 'does nothing' do
+    issues.create!(project_id: project.id, issue_type: 1)
 
-        expect(described_class::MIGRATION).to be_scheduled_delayed_migration(
-          2.minutes, issue_1.id, issue_1.id)
-        expect(described_class::MIGRATION).to be_scheduled_delayed_migration(
-          4.minutes, incident_1.id, incident_1.id)
-        expect(described_class::MIGRATION).to be_scheduled_delayed_migration(
-          6.minutes, incident_2.id, incident_2.id)
-        expect(BackgroundMigrationWorker.jobs.size).to eq(3)
-      end
-    end
+    expect { migrate! }.not_to change { BackgroundMigrationWorker.jobs.size }
   end
 end

spec/migrations/20220321234317_remove_all_issuable_escalation_statuses_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+require_migration!
+
+RSpec.describe RemoveAllIssuableEscalationStatuses do
+  let(:namespaces)  { table(:namespaces) }
+  let(:projects)    { table(:projects) }
+  let(:issues)      { table(:issues) }
+  let(:statuses)    { table(:incident_management_issuable_escalation_statuses) }
+  let(:namespace)   { namespaces.create!(name: 'foo', path: 'foo') }
+  let(:project)     { projects.create!(namespace_id: namespace.id) }
+
+  it 'removes all escalation status records' do
+    issue = issues.create!(project_id: project.id, issue_type: 1)
+    statuses.create!(issue_id: issue.id)
+
+    expect { migrate! }.to change(statuses, :count).from(1).to(0)
+  end
+end