Make `jobs/request` to be resillient

This makes this request and service
to be resillient to data integrity failures
and properly present them to user.

app/models/ci/build.rb

@@ -35,6 +35,10 @@ module Ci
       refspecs: -> (build) { build.merge_request_ref? }
     }.freeze
 
+    DEFAULT_RETRIES = {
+      scheduler_failure: 2
+    }.freeze
+
     has_one :deployment, as: :deployable, class_name: 'Deployment'
     has_many :trace_sections, class_name: 'Ci::BuildTraceSection'
     has_many :trace_chunks, class_name: 'Ci::BuildTraceChunk', foreign_key: :build_id
@@ -372,18 +376,25 @@ module Ci
       pipeline.builds.retried.where(name: self.name).count
     end
 
-    def retries_max
-      normalized_retry.fetch(:max, 0)
+    def retry_failure?
+      max_allowed_retries = nil
+      max_allowed_retries ||= options_retry_max if retry_on_reason_or_always?
+      max_allowed_retries ||= DEFAULT_RETRIES.fetch(failure_reason.to_sym, 0)
+
+      max_allowed_retries > 0 && retries_count < max_allowed_retries
     end
 
-    def retry_when
-      normalized_retry.fetch(:when, ['always'])
+    def options_retry_max
+      options_retry[:max]
     end
 
-    def retry_failure?
-      return false if retries_max.zero? || retries_count >= retries_max
+    def options_retry_when
+      options_retry.fetch(:when, ['always'])
+    end
 
-      retry_when.include?('always') || retry_when.include?(failure_reason.to_s)
+    def retry_on_reason_or_always?
+      options_retry_when.include?(failure_reason.to_s) ||
+        options_retry_when.include?('always')
     end
 
     def latest?
@@ -831,6 +842,13 @@ module Ci
       :creating
     end
 
+    # Consider this object to have a structural integrity problems
+    def doom!
+      update_columns(
+        status: :failed,
+        failure_reason: :data_integrity_failure)
+    end
+
     private
 
     def successful_deployment_status
@@ -875,8 +893,8 @@ module Ci
     # format, but builds created before GitLab 11.5 and saved in database still
     # have the old integer only format. This method returns the retry option
     # normalized as a hash in 11.5+ format.
-    def normalized_retry
-      strong_memoize(:normalized_retry) do
+    def options_retry
+      strong_memoize(:options_retry) do
         value = options&.dig(:retry)
         value = value.is_a?(Integer) ? { max: value } : value.to_h
         value.with_indifferent_access

app/models/commit_status_enums.rb

@@ -15,7 +15,9 @@ module CommitStatusEnums
       stale_schedule: 7,
       job_execution_timeout: 8,
       archived_failure: 9,
-      unmet_prerequisites: 10
+      unmet_prerequisites: 10,
+      scheduler_failure: 11,
+      data_integrity_failure: 12
     }
   end
 end

app/presenters/commit_status_presenter.rb

@@ -11,7 +11,9 @@ class CommitStatusPresenter < Gitlab::View::Presenter::Delegated
     stale_schedule: 'Delayed job could not be executed by some reason, please try again',
     job_execution_timeout: 'The script exceeded the maximum execution time set for the job',
     archived_failure: 'The job is archived and cannot be run',
-    unmet_prerequisites: 'The job failed to complete prerequisite tasks'
+    unmet_prerequisites: 'The job failed to complete prerequisite tasks',
+    scheduler_failure: 'The scheduler failed to assign job to the runner, please try again or contact system administrator',
+    data_integrity_failure: 'There has been a structural integrity problem detected, please contact system administrator'
   }.freeze
 
   private_constant :CALLOUT_FAILURE_MESSAGES
@@ -33,6 +35,6 @@ class CommitStatusPresenter < Gitlab::View::Presenter::Delegated
   end
 
   def unrecoverable?
-    script_failure? || missing_dependency_failure? || archived_failure?
+    script_failure? || missing_dependency_failure? || archived_failure? || scheduler_failure? || data_integrity_failure?
   end
 end

app/services/ci/register_job_service.rb

@@ -42,15 +42,34 @@ module Ci
       end
 
       builds.each do |build|
-        next unless runner.can_pick?(build)
+        result = process_build(build, params)
+        next unless result
+
+        if result.valid?
+          register_success(result.build)
+
+          return result
+        else
+          # The usage of valid: is described in
+          # handling of ActiveRecord::StaleObjectError
+          valid = false
+        end
+      end
+
+      register_failure
+      Result.new(nil, valid)
+    end
+    # rubocop: enable CodeReuse/ActiveRecord
+
+    private
+
+    def process_build(build, params)
+      return unless runner.can_pick?(build)
 
-        begin
       # In case when 2 runners try to assign the same build, second runner will be declined
       # with StateMachines::InvalidTransition or StaleObjectError when doing run! or save method.
       if assign_runner!(build, params)
-            register_success(build)
-
-            return Result.new(build, true)
+        Result.new(build, true)
       end
     rescue StateMachines::InvalidTransition, ActiveRecord::StaleObjectError
       # We are looping to find another build that is not conflicting
@@ -62,16 +81,16 @@ module Ci
       # In case we hit the concurrency-access lock,
       # we still have to return 409 in the end,
       # to make sure that this is properly handled by runner.
-          valid = false
-        end
-      end
+      Result.new(nil, false)
+    rescue => ex
+      raise ex unless Feature.enabled?(:ci_doom_build, default_enabled: true)
 
-      register_failure
-      Result.new(nil, valid)
-    end
-    # rubocop: enable CodeReuse/ActiveRecord
+      scheduler_failure!(build)
+      track_exception_for_build(ex, build)
 
-    private
+      # skip, and move to next one
+      nil
+    end
 
     def assign_runner!(build, params)
       build.runner_id = runner.id
@@ -96,6 +115,28 @@ module Ci
       true
     end
 
+    def scheduler_failure!(build)
+      Gitlab::OptimisticLocking.retry_lock(build, 3) do |subject|
+        subject.drop!(:scheduler_failure)
+      end
+    rescue => ex
+      build.doom!
+
+      # This requires extra exception, otherwise we would loose information
+      # why we cannot perform `scheduler_failure`
+      track_exception_for_build(ex, build)
+    end
+
+    def track_exception_for_build(ex, build)
+      Gitlab::Sentry.track_acceptable_exception(ex, extra: {
+        build_id: build.id,
+        build_name: build.name,
+        build_stage: build.stage,
+        pipeline_id: build.pipeline_id,
+        project_id: build.project_id
+      })
+    end
+
     # rubocop: disable CodeReuse/ActiveRecord
     def builds_for_shared_runner
       new_builds.

changelogs/unreleased/make-register-job-service-to-be-resillient.yml

+---
+title: Make `jobs/request` to be resillient
+merge_request: 19150
+author:
+type: fixed

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

@@ -16,7 +16,9 @@ module Gitlab
             stale_schedule: 'stale schedule',
             job_execution_timeout: 'job execution timeout',
             archived_failure: 'archived failure',
-            unmet_prerequisites: 'unmet prerequisites'
+            unmet_prerequisites: 'unmet prerequisites',
+            scheduler_failure: 'scheduler failure',
+            data_integrity_failure: 'data integrity failure'
           }.freeze
 
           private_constant :REASONS

spec/models/ci/build_spec.rb

@@ -1587,7 +1587,7 @@ describe Ci::Build do
       end
     end
 
-    describe '#retries_max' do
+    describe '#options_retry_max' do
       context 'with retries max config option' do
         subject { create(:ci_build, options: { retry: { max: 1 } }) }
 
@@ -1597,7 +1597,7 @@ describe Ci::Build do
           end
 
           it 'returns the number of configured max retries' do
-            expect(subject.retries_max).to eq 1
+            expect(subject.options_retry_max).to eq 1
           end
         end
 
@@ -1607,7 +1607,7 @@ describe Ci::Build do
           end
 
           it 'returns the number of configured max retries' do
-            expect(subject.retries_max).to eq 1
+            expect(subject.options_retry_max).to eq 1
           end
         end
       end
@@ -1615,16 +1615,16 @@ describe Ci::Build do
       context 'without retries max config option' do
         subject { create(:ci_build) }
 
-        it 'returns zero' do
-          expect(subject.retries_max).to eq 0
+        it 'returns nil' do
+          expect(subject.options_retry_max).to be_nil
         end
       end
 
       context 'when build is degenerated' do
         subject { create(:ci_build, :degenerated) }
 
-        it 'returns zero' do
-          expect(subject.retries_max).to eq 0
+        it 'returns nil' do
+          expect(subject.options_retry_max).to be_nil
         end
       end
 
@@ -1632,17 +1632,17 @@ describe Ci::Build do
         subject { create(:ci_build, options: { retry: 1 }) }
 
         it 'returns the number of configured max retries' do
-          expect(subject.retries_max).to eq 1
+          expect(subject.options_retry_max).to eq 1
         end
       end
     end
 
-    describe '#retry_when' do
+    describe '#options_retry_when' do
       context 'with retries when config option' do
         subject { create(:ci_build, options: { retry: { when: ['some_reason'] } }) }
 
         it 'returns the configured when' do
-          expect(subject.retry_when).to eq ['some_reason']
+          expect(subject.options_retry_when).to eq ['some_reason']
         end
       end
 
@@ -1650,7 +1650,7 @@ describe Ci::Build do
         subject { create(:ci_build) }
 
         it 'returns always array' do
-          expect(subject.retry_when).to eq ['always']
+          expect(subject.options_retry_when).to eq ['always']
         end
       end
 
@@ -1658,72 +1658,38 @@ describe Ci::Build do
         subject { create(:ci_build, options: { retry: 1 }) }
 
         it 'returns always array' do
-          expect(subject.retry_when).to eq ['always']
+          expect(subject.options_retry_when).to eq ['always']
         end
       end
     end
 
     describe '#retry_failure?' do
-      subject { create(:ci_build) }
-
-      context 'when retries max is zero' do
-        before do
-          expect(subject).to receive(:retries_max).at_least(:once).and_return(0)
-        end
-
-        it 'returns false' do
-          expect(subject.retry_failure?).to eq false
-        end
-      end
-
-      context 'when retries max equals retries count' do
-        before do
-          expect(subject).to receive(:retries_max).at_least(:once).and_return(1)
-          expect(subject).to receive(:retries_count).at_least(:once).and_return(1)
-        end
-
-        it 'returns false' do
-          expect(subject.retry_failure?).to eq false
-        end
-      end
+      using RSpec::Parameterized::TableSyntax
 
-      context 'when retries max is higher than retries count' do
-        before do
-          expect(subject).to receive(:retries_max).at_least(:once).and_return(2)
-          expect(subject).to receive(:retries_count).at_least(:once).and_return(1)
-        end
+      let(:build) { create(:ci_build) }
 
-        context 'and retry when is always' do
-          before do
-            expect(subject).to receive(:retry_when).at_least(:once).and_return(['always'])
-          end
+      subject { build.retry_failure? }
 
-          it 'returns true' do
-            expect(subject.retry_failure?).to eq true
-          end
+      where(:description, :retry_count, :options, :failure_reason, :result) do
+        "retries are disabled" | 0 | { max: 0 } | nil | false
+        "max equals count" | 2 | { max: 2 } | nil | false
+        "max is higher than count" | 1 | { max: 2 } | nil | true
+        "matching failure reason" | 0 | { when: %w[api_failure], max: 2 } | :api_failure | true
+        "not matching with always" | 0 | { when: %w[always], max: 2 } | :api_failure | true
+        "not matching reason" | 0 | { when: %w[script_error], max: 2 } | :api_failure | false
+        "scheduler failure override" | 1 | { when: %w[scheduler_failure], max: 1 } | :scheduler_failure | false
+        "default for scheduler failure" | 1 | {} | :scheduler_failure | true
       end
 
-        context 'and retry when includes the failure_reason' do
+      with_them do
         before do
-            expect(subject).to receive(:failure_reason).at_least(:once).and_return('some_reason')
-            expect(subject).to receive(:retry_when).at_least(:once).and_return(['some_reason'])
-          end
+          allow(build).to receive(:retries_count) { retry_count }
 
-          it 'returns true' do
-            expect(subject.retry_failure?).to eq true
-          end
+          build.options[:retry] = options
+          build.failure_reason = failure_reason
         end
 
-        context 'and retry when does not include failure_reason' do
-          before do
-            expect(subject).to receive(:failure_reason).at_least(:once).and_return('some_reason')
-            expect(subject).to receive(:retry_when).at_least(:once).and_return(['some', 'other failure'])
-          end
-
-          it 'returns false' do
-            expect(subject.retry_failure?).to eq false
-          end
-        end
+        it { is_expected.to eq(result) }
       end
     end
   end

spec/presenters/ci/build_presenter_spec.rb

@@ -269,7 +269,7 @@ describe Ci::BuildPresenter do
     let(:build) { create(:ci_build, :failed, :script_failure) }
 
     context 'when is a script or missing dependency failure' do
-      let(:failure_reasons) { %w(script_failure missing_dependency_failure archived_failure) }
+      let(:failure_reasons) { %w(script_failure missing_dependency_failure archived_failure scheduler_failure data_integrity_failure) }
 
       it 'returns false' do
         failure_reasons.each do |failure_reason|

spec/services/ci/create_pipeline_service_spec.rb

@@ -773,8 +773,8 @@ describe Ci::CreatePipelineService do
 
         it 'correctly creates builds with auto-retry value configured' do
           expect(pipeline).to be_persisted
-          expect(rspec_job.retries_max).to eq 2
-          expect(rspec_job.retry_when).to eq ['always']
+          expect(rspec_job.options_retry_max).to eq 2
+          expect(rspec_job.options_retry_when).to eq ['always']
         end
       end
 
@@ -783,8 +783,8 @@ describe Ci::CreatePipelineService do
 
         it 'correctly creates builds with auto-retry value configured' do
           expect(pipeline).to be_persisted
-          expect(rspec_job.retries_max).to eq 2
-          expect(rspec_job.retry_when).to eq ['runner_system_failure']
+          expect(rspec_job.options_retry_max).to eq 2
+          expect(rspec_job.options_retry_when).to eq ['runner_system_failure']
         end
       end
     end

spec/services/ci/register_job_service_spec.rb

@@ -502,6 +502,57 @@ module Ci
         end
       end
 
+      context 'when build has data integrity problem' do
+        let!(:pending_job) do
+          create(:ci_build, :pending, pipeline: pipeline)
+        end
+
+        before do
+          pending_job.update_columns(options: "string")
+        end
+
+        subject { execute(specific_runner, {}) }
+
+        it 'does drop the build and logs both failures' do
+          expect(Gitlab::Sentry).to receive(:track_acceptable_exception)
+            .with(anything, a_hash_including(extra: a_hash_including(build_id: pending_job.id)))
+            .twice
+            .and_call_original
+
+          expect(subject).to be_nil
+
+          pending_job.reload
+          expect(pending_job).to be_failed
+          expect(pending_job).to be_data_integrity_failure
+        end
+      end
+
+      context 'when build fails to be run!' do
+        let!(:pending_job) do
+          create(:ci_build, :pending, pipeline: pipeline)
+        end
+
+        before do
+          expect_any_instance_of(Ci::Build).to receive(:run!)
+            .and_raise(RuntimeError, 'scheduler error')
+        end
+
+        subject { execute(specific_runner, {}) }
+
+        it 'does drop the build and logs failure' do
+          expect(Gitlab::Sentry).to receive(:track_acceptable_exception)
+            .with(anything, a_hash_including(extra: a_hash_including(build_id: pending_job.id)))
+            .once
+            .and_call_original
+
+          expect(subject).to be_nil
+
+          pending_job.reload
+          expect(pending_job).to be_failed
+          expect(pending_job).to be_scheduler_failure
+        end
+      end
+
       context 'when an exception is raised during a persistent ref creation' do
         before do
           allow_any_instance_of(Ci::PersistentRef).to receive(:exist?) { false }