Introduce enqueue_scheduled event

app/models/ci/build.rb

@@ -22,7 +22,6 @@ module Ci
     }.freeze
     has_one :last_deployment, -> { order('deployments.id DESC') }, as: :deployable, class_name: 'Deployment'
-    has_one :build_schedule, class_name: 'Ci::BuildSchedule', foreign_key: :build_id
     has_many :trace_sections, class_name: 'Ci::BuildTraceSection'
     has_many :trace_chunks, class_name: 'Ci::BuildTraceChunk', foreign_key: :build_id
@@ -168,12 +167,26 @@ module Ci
         transition scheduled: :manual
       end
-      before_transition created: :scheduled do |build|
-        build.build_build_schedule(execute_at: build.execute_at)
+      event :enqueue_scheduled do
+        transition scheduled: :pending do
+          validate do |build|
+            build.scheduled_at && build.scheduled_at < Time.now
+          end
+        end
       end
       before_transition scheduled: any do |build|
-        build.build_schedule.delete
+        build.scheduled_at = nil
+      end
+
+      before_transition created: :scheduled do |build|
+        build.scheduled_at = build.get_scheduled_at
+      end
+
+      after_transition created: :scheduled do |build|
+        build.run_after_commit do
+          Ci::BuildScheduleWorker.perform_at(build.scheduled_at, build.id)
+        end
       end
       after_transition any => [:pending] do |build|
@@ -250,7 +263,7 @@ module Ci
       self.when == 'delayed' && options[:start_in].present?
     end
-    def execute_at
+    def get_scheduled_at
       ChronicDuration.parse(options[:start_in])&.seconds&.from_now
     end

app/models/ci/build_schedule.rb

-# frozen_string_literal: true
-
-module Ci
-  class BuildSchedule < ActiveRecord::Base
-    extend Gitlab::Ci::Model
-    include Importable
-    include AfterCommitQueue
-
-    belongs_to :build
-
-    validate :schedule_at_future
-
-    after_create :schedule, unless: :importing?
-
-    scope :stale, -> { where("execute_at < ?", Time.now) }
-
-    def execute_in
-      [0, self.execute_at - Time.now].max
-    end
-
-    private
-
-    def schedule_at_future
-      if self.execute_at < Time.now
-        errors.add(:execute_at, "Excute point must be somewhere in the future")
-      end
-    end
-
-    def schedule
-      run_after_commit do
-        Ci::BuildScheduleWorker.perform_at(self.execute_at, self.build_id)
-      end
-    end
-  end
-end

app/presenters/ci/build_presenter.rb

@@ -35,6 +35,10 @@ module Ci
       "#{subject.name} - #{detailed_status.status_tooltip}"
     end
+    def execute_in
+      [0, scheduled_at - Time.now].max
+    end
+
     private
     def tooltip_for_badge

app/services/ci/run_scheduled_build_service.rb

+# frozen_string_literal: true
+
+module Ci
+  class RunScheduledBuildService < ::BaseService
+    def execute(build)
+      unless can?(current_user, :update_build, build)
+        raise Gitlab::Access::AccessDeniedError
+      end
+
+      build.enqueue_scheduled!
+    end
+  end
+end

app/views/projects/ci/builds/_build.html.haml

@@ -104,9 +104,9 @@
         - elsif job.scheduled?
           .btn-group
             .btn.btn-default.has-tooltip{ disabled: true,
-              title: job.build_schedule.execute_at }
+              title: job.scheduled_at }
               = sprite_icon('planning')
-              = duration_in_numbers(job.build_schedule.execute_in)
+              = duration_in_numbers(job.execute_in)
             .btn.btn-default.btn-build.has-tooltip{ title: s_('DelayedJobs|Start now') }
               = sprite_icon('play')
             .btn.btn-default.btn-build.has-tooltip{ title: s_('DelayedJobs|Unschedule') }

app/workers/ci/build_schedule_worker.rb

@@ -6,10 +6,9 @@ module Ci
     include PipelineQueue
     def perform(build_id)
-      ::Ci::Build.find_by(id: build_id).try do |build|
-        break unless build.scheduled?
-
-        Ci::PlayBuildService.new(build.project, build.user).execute(build)
+      ::Ci::Build.find_by_id(build_id).try do |build|
+        Ci::RunScheduledBuildService
+          .new(build.project, build.user).execute(build)
       end
     end
   end

lib/gitlab/ci/status/build/scheduled.rb

@@ -23,7 +23,7 @@ module Gitlab
           private
           def execute_in
-            Time.at(subject.build_schedule.execute_in).utc.strftime("%H:%M:%S")
+            Time.at(subject.scheduled_at).utc.strftime("%H:%M:%S")
           end
         end
       end

scheduled_job_fixture.rb

@@ -64,15 +64,15 @@ cleanup:
 #
 # ### Reproduce the scenario ~ when all stages succeeded ~
 #
-# 1. ScheduledJobFixture.new(29, 1).create_pipeline('master')
-# 1. ScheduledJobFixture.new(29, 1).finish_stage_until('test')
+# 1. ScheduledJobFixture.new(16, 1).create_pipeline('master')
+# 1. ScheduledJobFixture.new(16, 1).finish_stage_until('test')
 # 1. Wait until rollout 10% job is triggered
-# 1. ScheduledJobFixture.new(29, 1).finish_stage_until('rollout 10%')
+# 1. ScheduledJobFixture.new(16, 1).finish_stage_until('rollout 10%')
 # 1. Wait until rollout 50% job is triggered
-# 1. ScheduledJobFixture.new(29, 1).finish_stage_until('rollout 50%')
+# 1. ScheduledJobFixture.new(16, 1).finish_stage_until('rollout 50%')
 # 1. Wait until rollout 100% job is triggered
-# 1. ScheduledJobFixture.new(29, 1).finish_stage_until('rollout 100%')
-# 1. ScheduledJobFixture.new(29, 1).finish_stage_until('cleanup')
+# 1. ScheduledJobFixture.new(16, 1).finish_stage_until('rollout 100%')
+# 1. ScheduledJobFixture.new(16, 1).finish_stage_until('cleanup')
 #
 # Expectation: Users see a succeccful pipeline
 #