calculate enrollment states after transaction

fixes CORE-2730

test plan
 - run sis import the deletes users with
   enrollments
 - restore sis import
 - the enrollments should have the correct state
   on the users page

Change-Id: I3f25ea56f3c033e522e891276befbcab3edb09ea
Reviewed-on: https://gerrit.instructure.com/188190
Tested-by: Jenkins
Reviewed-by: Cody Cutrer <cody@instructure.com>
QA-Review: Jeremy Putnam <jeremyp@instructure.com>
Product-Review: Rob Orton <rob@instructure.com>

app/models/enrollment/batch_state_updater.rb

@@ -188,20 +188,15 @@ class Enrollment::BatchStateUpdater
 
   # this is to be used for enrollments that just changed workflow_states but are
   # not deleted. This also skips notifying users.
-  def self.run_call_backs_for(batch)
+  def self.run_call_backs_for(batch, root_account=nil)
     raise ArgumentError, 'Cannot call with more than 1000 enrollments' if batch.count > 1_000
+    return if batch.empty?
     Enrollment.transaction do
       students = Enrollment.of_student_type.where(id: batch).preload({user: :linked_observers}, :root_account).to_a
       user_ids = Enrollment.where(id: batch).distinct.pluck(:user_id)
       courses = Course.where(id: Enrollment.where(id: batch).select(:course_id).distinct).to_a
-      root_account = courses.first.root_account
-      EnrollmentState.send_later_if_production_enqueue_args(
-        :force_recalculation,
-        {run_at: 1.minute.from_now,
-         n_strand: "restore_states_enrollment_states:#{root_account.global_id}}",
-         max_attempts: 2},
-        batch
-      )
+      root_account ||= courses.first.root_account
+      return unless root_account
       touch_and_update_associations(user_ids)
       update_linked_enrollments(students)
       needs_grading_count_updated(courses)
@@ -209,5 +204,14 @@ class Enrollment::BatchStateUpdater
       update_cached_due_dates(students, root_account)
       touch_all_graders_if_needed(students)
     end
+    root_account ||= Enrollment.where(id: batch).take&.root_account
+    return unless root_account
+    EnrollmentState.send_later_if_production_enqueue_args(
+      :force_recalculation,
+      {run_at: Setting.get("wait_time_to_calculate_enrollment_state", 1).to_f.minute.from_now,
+       n_strand: ["restore_states_enrollment_states", root_account.global_id],
+       max_attempts: 2},
+      batch
+    )
   end
 end

app/models/sis_batch.rb

@@ -770,7 +770,6 @@ class SisBatch < ActiveRecord::Base
   end
 
   def restore_workflow_states(scope, type, restore_progress, count, total)
-    count = 0
     Shackles.activate(:slave) do
       scope.active.order(:context_id).find_in_batches(batch_size: 5_000) do |data|
         Shackles.activate(:master) do
@@ -780,7 +779,7 @@ class SisBatch < ActiveRecord::Base
               ids = type.constantize.connection.select_values(restore_sql(type, data.map(&:to_restore_array)))
               if type == 'Enrollment'
                 ids.each_slice(1000) do |slice|
-                  Enrollment::BatchStateUpdater.send_later_enqueue_args(:run_call_backs_for, {n_strand: "restore_states_batch_updater:#{account.global_id}}"}, slice)
+                  Enrollment::BatchStateUpdater.send_later_enqueue_args(:run_call_backs_for, {n_strand: ["restore_states_batch_updater", account.global_id]}, slice, self.account)
                 end
               end
               count += update_restore_progress(restore_progress, data, count, total)
@@ -799,7 +798,7 @@ class SisBatch < ActiveRecord::Base
                 end
               end
               successful_ids.each_slice(1000) do |slice|
-                Enrollment::BatchStateUpdater.send_later_enqueue_args(:run_call_backs_for, {n_strand: "restore_states_batch_updater:#{account.global_id}}"}, slice)
+                Enrollment::BatchStateUpdater.send_later_enqueue_args(:run_call_backs_for, {n_strand: ["restore_states_batch_updater", account.global_id]}, slice, self.account)
               end
               count += update_restore_progress(restore_progress, data - failed_data, count, total)
               roll_back_data.active.where(id: failed_data).update_all(workflow_state: 'failed', updated_at: Time.zone.now)
@@ -815,7 +814,7 @@ class SisBatch < ActiveRecord::Base
     self.shard.activate do
       restore_progress = Progress.create! context: self, tag: "sis_batch_state_restore", completion: 0.0
       restore_progress.process_job(self, :restore_states_for_batch,
-                                   {n_strand: "restore_states_for_batch:#{account.global_id}}"},
+                                   {n_strand: ["restore_states_for_batch", account.global_id]},
                                    {batch_mode: batch_mode, undelete_only: undelete_only, unconclude_only: unconclude_only})
       restore_progress
     end

spec/models/enrollment/batch_state_updater_spec.rb

@@ -24,6 +24,10 @@ describe "Enrollment::BatchStateUpdater" do
       to raise_error(ArgumentError, 'Cannot call with more than 1000 enrollments')
   end
 
+  it 'should not fail with more than empty batch' do
+    expect { Enrollment::BatchStateUpdater.run_call_backs_for([], nil) }.to_not raise_error
+  end
+
   before(:once) do
     @enrollment2 = course_with_teacher(active_all: true)
     @user2 = @enrollment2.user